book of abstracts - IM2NP

3 rd International Conference on 

NANO-structures Self-Assembly 

Congress Center of Cassis, French Riviera 

28 June – 2 July 2010 

NanoSEA 2010 

www.im2np.fr/nanosea2010 

Organisers : 

I. Berbezier, Im2np – CNRS – Université Paul Cézanne, Marseille, France 

M. De Crescenzi, Universita di Roma Tor Vergata, Roma, Italy

NANOSEA 2010 

International Conference

General Information ......................................................................................................................... 7 

Monday, June 28 .................................................................................................................................. 9 

Session 1 Room Calendal .................................................................................................................... 9 

Nanowires (Chairman: Lannoo).................................................................................................... 9 

Session 2 Room Calendal .................................................................................................................. 10 

Nanowires (Chairman: Vvedensky) ........................................................................................... 10 

Session 3 Room Port-Pin .................................................................................................................. 11 

Biomaterials (Chairman: Rowell) ................................................................................................. 11 

Tuesday, June 29 ................................................................................................................................. 29 

Session 4 Room Calendal ................................................................................................................. 29 

Near Field Microscopy (Chairman: Teichert) .......................................................................... 29 


Local Chemical and Structural Characterization (Chairman: Hillenbrand) .................. 30 

Session 6 Room Port-Pin ................................................................................................................. 31 

Si based Nanostructures (Chairman: Le Thanh) ..................................................................... 31 

Session 7 Room Port-Pin ................................................................................................................. 32 

Session Poster P1-P2 ........................................................................................................................ 33 

Wednesday, June 30 ......................................................................................................................... 58 


Organic Nanostructures (Chairman: De Crescenzi) ............................................................. 58 


Organic Nanostructures (Chairman: Porte) ............................................................................ 59 

Session 10 Room Port-Pin ............................................................................................................. 60 

Magnetic Nanostructuration (Chairman : )............................................................................. 60 


Zn-Based-Nanostructures (Chairman: Grosso) ........................................................................ 61 

3

Thursday, July 1 .................................................................................................................................... 79 

Session 12 Room Calendal ............................................................................................................. 79 

III-V Semiconductors (Chairman: Mesli) .................................................................................... 79 

Session 13 Room Calendal ............................................................................................................. 80 

Growth and Self Organisation (Chairman : Tersoff) .............................................................. 80 

Session 14 Room Calandar ............................................................................................................ 81 

Island (Chairman: Ronda) ............................................................................................................ 81 


Opto-Electronic Properties (Chairman: Del Sole)................................................................... 82 


Nanostructured Substrates (Chairman: Venables) ............................................................... 83 


Metallic Nanoparticles (Chairman: Fiorani) ............................................................................ 84 

Friday, July 2 ........................................................................................................................................ 116 

Session 18 Room Calendal ........................................................................................................... 116 

Mesoporous Systems (Chairman: )........................................................................................... 116 

Session 19 Room Calendal ........................................................................................................... 117 

Self Assembly (Chairman: Noguera) ....................................................................................... 117 

Session 20 Room Port-Pin ........................................................................................................... 118 

Carbon Nanotubes (Chairman: Berbezier) ........................................................................... 118 

Session 21 Room Port-Pin ........................................................................................................... 119 

Nanotubes and Coatings (Chairman: Goniakowski) ......................................................... 119 

4

NANOSEA 2010 International Conference 

NANOSEA 2010 International Conference is the third edition of NANOSEA, four years after the successful start 

in July 2006 in Aix-en-Provence , France (www.im2np.fr/nanosea2006/) and two years after NANOSEA 2008 

(www.nanosea2008.roma2.infn.it) held in the magnificent Villa Mondragone Conference Center , one of the most 

beautiful Tuscolum villas. 

NANOSEA 2010 will be held in the ancient fishing port of Cassis rebuilt in the 18th century situated at 20 km of 

Marseilles . Cassis has become the most charming station along the coast surrounded by two exceptional domains : 

the Cap Canaille, highest european cliff (418m) and the Calanques, 23km of untouched rocky inlets until 

Marseille. The Congress Center of Cassis is located between the beach and the port and has an incredible view on 

the port with its boats and inviting terraces. 

General Information 

Research on nanostructures self-assembled encompasses fundamental issues in crystal growth and the scaling of 

materials properties to molecular dimensions, and work on possible applications of nanoscale assemblies in 

advanced devices. The goal of this conference is to bring together the broad, multidisciplinary community of 

researchers who are interested in the field of nanostructures and the opportunities for future high-impact science 

and technology related to such field. 

The Conference will provide a common forum for scientists operating in all the fields of nanostructures from their 

formation and modelling to their properties and applications. The conference will cover the physics of 

nanostructures at the nanoscale, new fabrication procedures of nanostructures with well defined size, shape and 

composition, and also: 

- large-scale patterning obtained by spontaneous structuring as well as local probe nanopatterning for size and 

position control of nanostructures; 

- theoretical and experimental efforts dedicated to a better understanding of the formation, evolution and 

organisation of nanoscale systems; 

- fundamental and new issues in nucleation, crystal growth, surface and interface atomistic mechanisms and 

electronic structure; 

- optical, electrical, magnetic and mechanical properties representative of the self-assembled systems; Novel 

properties induced by low scale nanostructures. 

Finally, new insights on short-term and future/futuristic device applications will be of prime interest in the 

framework of this Conference. 

5

Scope 

NANOSEA 2010 will primarily focus on the following topics that are of strong current interest in fields of 

nanostructures self-assembling and nanopatterned substrate: 

Nanostructured Materials : 

- Semiconductor - Metallic - Organic - Biological - New materials and structures 

Nanostructures classes : 

- Quantum dots, quantum wires and quantum wells - Nanotubes and nanorods - Nanoparticles and 

Nanoprecipitates - Nanoporous material - Very thin multilayers and superlattices 

Local structure of nanostructures : 

- Effects of local structure on properties in nanostructured materials - Quantitative characterization of 

atomic arrangements - Characterization of nanoparticle surfaces - Characterization of internal interfaces 

Self-assembling techniques : 

- Nanopatterning by lithographic techniques - Ion-beam lithography and patterning - Nanopore 

fabrication and Pore filling - Substrate nanostructuring - Co-polymer template - Surface passivation - 

Functionalisation and catalysts – Nanofabrication 

Modelling : 

- Self-organisation and pattern formation - Thermodynamics and kinetics of nucleation and growth - Ab 

initio theory for spintronic materials and spin transport - Defects and impurities - Non-radiative and relaxation 

processes – Transport 

Properties : 

- Electronic and optical - Magnetic - Size dependent properties and transport - Mechanical - Structure, 

microstructure, and morphology 

Applications : 

- Novel microelectronic device - Nanoelectronic devices - Molecular devices - Nanodevice fabrication 

technology, characterization, properties and modelling - Photonic and photovoltaic devices - Chemical and 

biological sensors - Multifunctional spin devices - Magnetic random access memories (MRAM) - Other 

applications in medicine, biology, energy and environment … 

Web site : www.im2np.fr/nanosea2010 

6

Committees 

International Scientific Committee 

Aziz Univ. Harvard U.S.A. maziz@harvard.edu 

Bensahel STMicroelectronics France daniel.bensahel@st.com 

Del Sole Uni. Tor Vergata Italy Rodolfo.delsole@roma2.infn.it 

Kasper Erich Uni. Stuttgart Germany 

Kelires Univ. Crete Greece kelires@physics.uoc.gr 

Nogera INSP Insitut des Nanosciences de Paris France noguera@insp.jussieu.fr 

Nozaki Univ. Electro-Commun. Japan nozaki@ee.uec.ac.jp 

Nylandsted Larsen Univ. Aarhus Denmark anl@phys.au.dk 

Porte IM2NP France louis.porte@im2np.fr 

Ronda IM2NP France Antoine.ronda@im2np.fr 

Rowell NRC Canada nelson.rowell@nrc-cnrc.gc.ca 

Valbusa Univ. Genova Italy Valbusa@fisica.unige.it 

Valeri Univ. Modena Italy valeri@unimo.it 

Vveddensky Imperial College UK d.vvedensky@imperial.ac.uk 

Wiesendanger Univ. Hambourg Germany rwiesend@physnet.uni-hamburg.de 

Zanoni Uni. Roma La Sapienza Italy robertino.zanoni@uniroma1.it 

Organizing Committee 

Guillaume Amiard, Uni Paul Cézanne, CNRS, Marseilles France 

Mansour Aouassa, Uni Paul Cézanne, Marseilles France and Uni Monastir, Tunisia 

Franck Bassani , Uni Paul Cézanne, CNRS, Marseilles France 

Paola Castrucci, Uni Roma Tor Vergata, Italy 

Luc Favre , Uni Paul Cézanne, CNRS, Marseilles France 

Philippe Ferrandis , Uni Paul Cézanne, CNRS, Marseilles France 

Elise Gomes, Uni Paul Cézanne, CNRS, Marseilles France 

Adrien Gouyé, Uni Paul Cézanne, CNRS, Marseilles France 

Cathy Paitel, CNRS, Marseilles France 

Stéphane Riou, CNRS, Marseilles France 

Manuela Angela Scarselli, Uni Roma Tor Vergata, Italy 

Chairpersons 

Isabelle Berbezier 

Im2np - CNRS 

Marseilles, France 

Maurizio De Crescenzi 

Universita Di Roma 

Tor Vergata, Roma, Italy 

7

P R O G R A M MONDAY, JUNE 28 N A N O S E A 2 0 1 0 

Monday, June 28 

Session 1 

Room Calendal 

Nanowires (Chairman: Lannoo) 

10h00-10h30 

Introduction Speech 

Michel Lannoo 

10h30-11h10 

J. Tersoff (IBM Watson Research Center Yorktown Heights NY 10598 USA) 

Nanoscale phase transitions and nanowire growth 

11h10-11h30 

S. Tatarenko (Nanophysics and Semiconductors Group, INAC and Institut NEEL, CEA/CNRS/University 

Joseph Fourier, France) 

Microstructure and compositional study of MBE grown ZnSe NWs with CdSe 

inclusions 

11h30-11h50 Del Sole ((1) Laboratoire des Solides Irradies, Ecole Polytechnique - CNRS 

(2) Dip. di Fisica, CNISM, Universita‟ di Roma Tor Vergata, Roma, Italy 

(3) Dip. di Scienze e Metodi dell'Ingegneria, Università di Modena e Reggio Emilia, Italy 

(4) European Theoretical Spectroscopy Facility) 

Many body approach for the excitonic effects in 1D and 2D silicon doped 

nanostructures 

11h50-12h20 

Depadova (1CNR-ISM, via Fosso del Cavaliere, 00133 Roma, Italy; 2Instituto de Ciencia de Materiales de 

Madrid, CSIC, Cantoblanco 28049 Madrid, Spain; 3MAX-Lab, Lund University, Box 118 221 00 Lund, Sweden; 

4Consiglio Nazionale delle Ricerche-ISAC, via Fosso del Cavaliere, 00133 Roma, Italy; 5CINaM-CNRS, Campus 

de Luminy, Case 913, 13288 Marseille Cedex 9, France) 

One-dimensional Mn nano-wires on a ordered array of silicon nano-ribbons 

12h20-12h50 

Kawai (8-1,Mihogaoka, Ibaraki, Osaka, Japan) 

Self-assembled metal oxide Nanowires: Synthesis, Properties and Non-voltile 

Memory Applciations 

12h50-17h00 

Lunch and Break 

9


Session 2 

Room Calendal 

Nanowires (Chairman: Vvedensky) 

17H00-17H30 

Calarco (1 Institute of Bio- and Nanosystems (IBN-1), Research Centre Jülich GmbH, 52425 Jülich, Germany, 

and JARA-FIT Fundamentals of Future Information Technology. 2 Center for Functional Nanomaterials, 

Brookhaven National Laboratory, Upton, New York 11973. 3 Phys. Department and CNISM, University of Bologna, 

Viale Berti Pichat 6/2, 40127 Bologna, Italy.) 

Nitride nanowires: from nucleation to optoelectrical measurements 

17H30-17H50 

Buick (1 Dipartimento di Fisica, CNISM, Universita‟ di Roma Tor Vergata, 00133 Roma, Italy. 2 IMM-CNR, 

Unità di Lecce, Via Arnesano, 73100 Lecce, Italy. 3 CNISM, and Dipartimento di Ingegneria dell‟Innovazione, 

Università del Salento, Via Arnesano, 73100 Lecce, Italy) 

Probing Single AlGaAs Core-Shell Nanowires by Raman Spectroscopy 

17H50-18H10 Carratero (1. Institut de Ciència de Materials de Barcelona-CSIC, Campus UAB, 08193 Bellaterra, Spain2. 2 

Université Catholique de Louvain, B-1340 Louvain la Neuve, Belgium) 

Synthesis and self-assembled of 1-D nanostructures based on La0.3Sr0.7MnO3 from 

template directed chemical solution deposition 

18H10-18H30 

Gibert (Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, 08193 Bellaterra, Catalonia, Spain) 

Self-organized Ce1-xGdxO2-y Nanowire Networks with Ultrafast Coarsening 

resulting from Anisotropic Strain 

18H30-18H50 

Boarino (1 NanoFacility Piemonte, Electromagnetism Division, Istituto Nazionale di Ricerca Metrologica, Strada 

delle Cacce 91 - 10135 Turin, Italy2 Dept. of Structural and Geotechnical Eng., Politecnico di Torino, C.so Duca 

degli Abruzzi 24 - 10148Turin, Italy) 

Fabrication of Ordered Silicon Nanowires by Self-Assembling and Metal Assisted 

Etching 

18H50-19H10 

Tanemura (1. Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, No.2 Nengyuan Road, 

Wushan, Tianhe district, Guangzhou, 510640, P.R.China; 2. Japan Fine Ceramic Center, 2-4-1 Mutsuno, Atsuta-ku, 

Nagoya 456-8587, Japan; 3. Key Laboratory of Polarized Materials and Devices, Ministry of Education, East China 

Normal University, Shanghai 200062, China). miaolei@ms.giec.ac.cn, *tanemura-sakae@jfcc.or.jp, 

rhuang@ee.ecnu.edu.cn 

Synthesis of cation-intercalated titanate nanobelts. 

10


Monday, June 28 

Session 3 

Room Port-Pin 

Biomaterials (Chairman: Rowell) 

17H00-17H30 

Iyer (Centre for Strategic Nano-fabrication, School of Biomedical, Biomolecular and Chemical Sciences, The 

University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia; 2 Experimental and 

Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, 35 Stirling Highway, 

Crawley WA 6009, Australia; 3 School of Anatomy and Human BiologyThe University of Western Australia, 35 

Stirling Highway, Crawley WA 6009, Australia) 

Applications of Nano-assembly in Neuroscience: From Multimodal Imaging to 

Regenerative Scaffolds 

17H30-17H50 Chang (Korea Institute of Ceramic Engineering and technology, 233-5 Gasan-dong, Guemcheon-gu, Seoul, 153- 

801, Korea) 

Functionalized Magnetic Nanomaterials for Clinical Bio-separation 

17H50-18H10 

HE (1 CNRS ; LAAS ; 7, avenue du Colonel Roche, F-31077 Toulouse, France2 Université de Toulouse ; UPS, 

INSA, INP, ISAE ; LAAS-CNRS : F-31077 Toulouse, France) 

Micropatterned poly-acrylamid gels for colloids self assembly and bio-assays. 

18H10-18H30 

Amdursky.(†Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life 

Sciences, Tel Aviv University, Tel Aviv, 69978, Israel‡Department of Electrical Engineering-Physical Electronics, 

School of Engineering, Tel Aviv University, Tel Aviv, 69978, Israel) 

Quantum Confinement approach for the self-assembly process of peptide and 

proteins structures 

18H30-18H50 

Roth (1HASYLAB-DESY, Notkestr. 85, D-22607 Hamburg, Germany; 2TU-Muenchen, Physik-Department 

Lehrstuhl E13, Garching, Germany; 3K.U. Leuven, Afdeling Kern- en Stralingsfysica, 3001 Heverlee, Belgium) 

Creating biofibre-noble metal nanocomposites - an in situ sputter deposition 

investigation 

18H50-19H10 

Severac (LAAS-CNRS - 7, avenue du Colonel Roche 31077 Toulouse Cedex 4 FRANCE.) 

Toward multifunctional energetic materials nanostructuration through DNA directed 

nanoparticles self assembly. 

11

A B S T R A C T S MONDAY, JUNE 28 N A N O S E A 2 0 1 0 

Room Calendal 

10h30-11h10 

Nanoscale phase transitions and nanowire growth. 

J. Tersoff (IBM Watson Research Center Yorktown Heights NY 10598 USA) 

Semiconductor nanowires can be readily grown from tiny catalyst particles. These wires, with diameters as 

small as a few nanometers, have attracted intense interest due to their potential applications in nanoscale 

technologies. At the same time, they offer a unique opportunity to deepen our understanding of crystal 

growth. It has long been realized that novel effects are expected for growth at the nanoscale. But only 

recently has it become possible to measure these effects directly, using in-situ microscopy. 

This talk will describe some recent progress in understanding growth at the nanoscale, by combining 

experimental observations, theoretical modeling, and direct computer simulation of nanowire growth [1-3]. 

We studied the sequence of phase transformations as a Au seed particle is exposed to disilane to initiate 

nanowire growth. On an inert substrate and above the eutectic temperature, the system progresses from Au 

to a two-phase Au+AuSi eutectic system, to liquid AuSi, and finally to AuSi+Si, initiating nanowire growth 

[2,3]. By comparing the experimental measurements with a simple theoretical model, we determine the 

changes in the equilibrium phase diagram for nanoscale systems, and the effect of system size on the 

nucleation process. We also find dramatic deviations from equilibrium due to kinetic effects in nanowire 

growth. We have developed a theoretical model for the eutectic system evolution, allowing direct computer 

simulation of nanowire growth [3]. These simulations shed light on how material properties and growth 

conditions control the wire morphology and growth stability [3]. 

* Work done in collaboration with K.W. Schwarz, B.J. Kim, S. Kodambaka, E.A. Stach, and F.M. Ross. 

[1] B. J. Kim, J. Tersoff, S. Kodambaka, M. C. Reuter, E. A. Stach, and F. M. Ross, Science 322, 1070 (2008). 

[2] K. W. Schwarz and J. Tersoff, Phys. Rev. Lett. 102, 206101 (2009). 

[3] B. J. Kim, J. Tersoff, C.-Y. Wen, M. C. Reuter, E. A. Stach, and F. M. Ross, Phys. Rev. Lett. 103, 155701 (2009) 

11h10-11h30 

Microstructure and compositional study of MBE grown ZnSe NWs with 

CdSe inclusions. 

S. Tatarenko (Nanophysics and Semiconductors Group, INAC and Institut NEEL, CEA/CNRS/University 

Joseph Fourier, France) serge.tatarenko@grenoble.cnrs.fr 

We have recently shown that a single CdSe quantum dot embedded in a ZnSe nanowire (NW) is an efficient 

single photon source operating at a temperature as high as 220K [1]. However, when grown on an oxidized 

Si (001) substrate in the VLS growth mode catalyzed by gold particles, the NWs present a random 

distribution of orientations and densities. 

In this contribution we report on the epitaxial growth of ZnSe/CdSe NWs on 2D epitaxial ZnSe (100) on 

GaAs (100) substrate. Scanning electron microscopy (SEM) and High Resolution Transmission Electron 

Microscopy (HRTEM) images (Fig 1) show ZnSe NWs with hexagonal wurtzite structure along the [0001] 

axis and also NWs with cubic zinc-blende structure along the [100] axis. The presence of different NW 

orientations is attributed in part to the formation of [110] oriented nanotrenches generated by Au dewetting 

at 530°C [2, 3]. The first steps of the growth for both growth directions will be presented in details as well 

as the influence of the growth parameters. 

12


The microstructure of NWs including a CdSe quantum dot has been studied in detail by HRTEM. In Fig. 2 

the ZnSe NW adopts the hexagonal wurtzite-type structure with growth along the [0001] axis. The CdSe 

inclusions were identified by Energy Dispersive X-ray spectroscopy as well as by interplanar spacing 

variations along the wire axis obtained by the Geometrical Phase Analysis of an HRTEM micrograph. 

Energy Filtered TEM image demonstrate the absence of Zn in the CdSe region indicating limited 

interdiffusion (Zn map in Fig. 3a). It is worth noting that in this NW, the crystalline structures of the ZnSe 

part and inclusion part are opposite to their bulk-form case, know to be cubic and hexagonal for ZnSe and 

CdSe respectively. 

For the same deposition time, the CdSe inclusions are as small as 1.5nm long when growth occurs at 450°C 

(Fig. 2b), while the inclusion length can reach 20nm for growth at 400°C (Fig. 3). This result opens the way 

to a control over the shape (disk or cylinder) of the inclusion, and consequently on the tuning of its optical 

properties (wavelength, polarisation, efficiency…). Finally we will present the PL results obtained on single 

NWs with CdSe insertion of different lengths. 

[1] A. Tribu et al. Nano Lett. 8, 4326 (2008) 

[2] S.K. Chan et al, Appl. Phys. Lett. 92, 183102 (2008) 

[3] E. Bellet-Amalric et al in press 

b 

Hexagonal 

c 

Cubic 

8 nm 

10 nm 

Figure 1 - SEM image (a) and TEM images of a hexagonal (b) and a cubic (c) ZnSe nanowires grown on a ZnSe (001) buffer layer 

b 

a 

c 

Figure 2 

(a) HRTEM image of a ZnSe nanowire 

with a CdSe insertion grown at 450°C. 

(b) Zoom of the inset showing the 

wurzite / zinc blende transition 

(c) Map of the d-spacing along the 

growth axis obtained for the same wire 

Figure 3 - TEM (A, B) and EFTEM (C) of a ZnSe NW with a CdSe insertion 

grown at 400°C. 

13


11h30-11h50 

Many body approach for the excitonic effects in 1D and 2D silicon doped 

nanostructures. 

Del Sole ((1) Laboratoire des Solides Irradies, Ecole Polytechnique - CNRS 

(2) Dip. di Fisica, CNISM, Universita‟ di Roma Tor Vergata, Roma, Italy 

(3) Dip. di Scienze e Metodi dell'Ingegneria, Università di Modena e Reggio Emilia, Italy 

(4) European Theoretical Spectroscopy Facility) 

Silicon Nanowires (Sinw) and Silicon Nanoribbons (Sinr) are one- (1D) and two- (2D) dimensional 

nanostructures which are attracting in the last years increasing interest for potential nanoelectronic and 

nanophotonic applications. Sinw have made an impact in applications in fields as diverse as electronics, 

photonic, sensing, biology and photovoltaics , while Sinr, recently realized, seems to be promising as well, 

maybe even more than the 1D systems for silicon basednanotechnology application. 

In this theoretical work we investigate mainly the electronic and the optical properties of 1D and 2D system 

with and without the presence of impurities. The size and doping dependence of the electron-hole exchange 

interaction in Si nanowires is investigated from first-principles. In pure Si nanowires we found excitonic 

exchange splittings in very good agreement with the experimental results for porous silicon. For n-doped Si 

nanowires a giant singlet-triplet splitting, three order of magnitude bigger than in bulk silicon, is predicted as 

due to the dramatic enhancement of the electron and the hole probability of being in the same place at the 

same time. For the Sinr we have calculated the dielectric function for different light polarization in and 

outside the plane by taking into account many body effect. 

11h50-12h20 

One-dimensional Mn nano-wires on a ordered array of silicon nanoribbons. 

P. De Padova1, M. E. Dávila2, F. Hennies3, A. Pietzsch3, N. Shariati3, C. 

Ottaviani1, C. Quaresima1, B. Olivieri4, F. Ronci1, S. Colonna1, A. Cricenti1, B. 

Aufray5, G. Le Lay5 (1CNR-ISM, via Fosso del Cavaliere, 00133 Roma, Italy. 2Instituto de Ciencia de 

Materiales de Madrid, CSIC, Cantoblanco 28049 Madrid, Spain. 3MAX-Lab, Lund University, Box 118 221 00 

Lund, Sweden. 4Consiglio Nazionale delle Ricerche-ISAC, via Fosso del Cavaliere, 00133 Roma, Italy. 5CINaM- 

CNRS, Campus de Luminy, Case 913, 13288 Marseille Cedex 9, France) 

Silicon nano-ribbons (SiNRs) are one of the more promising systems for studying the role of dimensionality 

on physical properties for potential applications in nanoscale electronics or spintronics. Room temperature 

(RT) deposition of low coverages of Si on the Ag(110) surface produces massively parallel Si nano-ribbons 

(SiNRs) along the [–110] direction. They have a magic width of 16 Å, unprecedented spectral signatures in 

valence band and core-level spectroscopy and unique burning match-like oxidation behavior. Upon 

annealing, a very well ordered array of SiNRs, in a 5x2/5x4 arrangement, is obtained on the Ag(110) 

substrate. 

Si was evaporated on Ag(110) substrate at a rate of ~ 0.03 ML/min from a Si source, while the sample was 

heated at 440 K to obtain a dense array SiNRs (5x2/5x4 reconstruction). LEED observations were used to 

monitor the x2 and 5x2/5x4 superstructures. 

Core level spectroscopy data have been taken at the VUV beamline of ELETTRA (Trieste). The photon 

energies used for Si 2p core level was 135.8 eV. 

Here we report the electronic and structural properties of Mn grown on a dense array of well-ordered SiNRs 

on Ag(110). High-resolution Si 2p core levels show an interesting selective adsorption of Mn atoms on the 

SiNRs as clearly evidenced by the collection of high-resolution scanning tunneling microscopy images. We 

14


found an unusual one-dimensional growth of Mn on top of the dense array of SiNRs, which act s as a 

template at atomic scale. 

The Si 2p spectrum of the Si/Ag(110)5 2/5x4 reconstruction shows two main components, S1 and S2 as 

those reported [1,2] for the Si/Ag(110) 2 one. After the adsorption of Mn a new reacted component, RMn- 

Si, chemically shifted by 0.45 eV towards higher kinetic energy (32.5 eV), is clearly evident. Interestingly, 

one notices that the Mn atoms affect only the S2 component; in fact, the S1 is absolutely unaltered. This 

shows that the Mn atoms are adsorbed preferentially on just one Si site and, consequently, that they form 

straight Mn-Si nanostripes along the [-110] direction on the Si/Ag(110)5 2/5x4 substrate. 

We studied the Mn adsorption on dense array of Si NRs grown on Ag(110) by STM and Si 2p core level 

spectroscopy. Very interesting one-dimensional Mn nano-wires were realized. 

12h20-12h50 

Self-assembled metal oxide Nanowires: Synthesis, Properties and Nonvoltile 

Memory Applciations. 

T. Kawai (8-1,Mihogaoka, Ibaraki, Osaka, Japan) 

Self-assembled Metal oxides nanowires are potential candidates towards functional nanowire-based devices 

due to their fascinating physical properties, including resistive switching memory effect. Within the 

framework of conventional vapor-liquid-solid self-assembly mechanism to form the nanowires, there is a 

fundamental limitation to create diverse metal oxide nanowires. Heterostructured nanowires are most 

promising ways to overcome such difficulties. Our recent progress will be reported on the synthesis of selfassembled 

heterostructured nanowires using metal oxides, the transport properties, and the non-volatile 

memory applications. The oxide heterostructured nanowires were fabricated by in-situ laser MBE technique 

taking advantage of seeds based self-assembly process that has been newly developed. Various kinds of 

oxide heterostructured nanowires can be fabricated using the in-situ technique, TiO2/MgO, Fe3O4/MgO, 

NiO/MgO , MgO/Fe3O4/NiO. When forming the oxide heterostructured nanowires, the lattice matching in 

3D was found to be a crucial factor to fabricate the well-defined epitaxial heterointerface. The atomic intermixing 

at the heterointerface and the surface oxidization were found to play a crucial role on the transport 

properties of metal oxide nanowires. Furthermore, we found the resistive switching memory effect within the 

single metal oxide nanowire by utilizing nano-gap electrodes and C-AFM method. Thus the metal oxide 

nanowires are expected to open up opportunities to explore not only the detailed nanoscale properties of 

metal oxides but also next-generation nanoscale oxide devices with the potential of high-density device 

integration and the improved device characteristics. 

[1] Appl. Phys. Lett., 90, 233103 (2007), 

[2] Appl. Phys. Lett., 91, 061502 (2007), 

[3] J. Appl. Phys., 101, 124304 (2007), 

[4] J. Appl. Phys., 102, 016102 (2007), 

[5] J. Am. Chem. Soc., 130, 5378 (2008), 

[6] Appl. Phys. Lett., 92, 173119 (2008), 

[7] J. Appl. Phys., 104, 016101 (2008), 

[8] J. Appl. Phys., 104, 013711 (2008), 

[9] Appl. Phys. Lett., 93, 153103 (2008), 

[10] J. Phys. Chem. C, 112, 18923 (2008), 

[11] J. Am. Chem. Soc., 131, 3434 (2009) 

15


Room Calendal 

17H00-17H30 

Nitride nanowires: from nucleation to optoelectrical measurements 

R. Calarco, Toma Stoica1, Eli Sutter2, Ralph Meijers1, Thomas Schäpers1, Thomas 

Richter1, Ratan K. Debnath1, Michel Marso1, Hans Lüth1, A. Cavallini3, L. 

Polenta3, M. Rossi3. (1 Institute of Bio- and Nanosystems (IBN-1), Research Centre Jülich GmbH, 52425 

Jülich, Germany, and JARA-FIT Fundamentals of Future Information Technology. 2 Center for Functional 

Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973. 3 Phys. Department and CNISM, 

University of Bologna, Viale Berti Pichat 6/2, 40127 Bologna, Italy.) 

1 – Introduction 

In recent years III-nitride based nanowires have attracted a lot of interest because of their potential 

applications for nanoelectronic devices [1-5]. III-nitride NWs are indeed extremely interesting due to the fact 

that on the one hand they possess impressive material properties and on the other hand they constitute a 1D 

structure. The combination of both aspects offers the possibility of studying fundamental issues of transport 

properties, often with tight feed back to the optimization of growth. 

2 – Abstract 

We showed that the growth of Nitride nanowires by MBE occurs on various substrates under appropriate 

growth conditions without using a liquid-phase catalyst, i.e. a droplet, at the top of the growing nanowire. 

We addressed the optimization [6, 7] of the crystalline and optical quality of nitride nanowires as well as the 

nucleation, kinetics and growth mechanisms [8, 9]. We observed that the growth is characterized by a long 

nucleation period [8], which results in a broad distribution of the nanowire sizes. A diffusion mechanism was 

found to dominate the NW growth after the nucleation period and can explain the diameter dependence of 

the NW length [9]. In addition, it was demonstrated that nanowire growth occurs perpendicular to the 

substrate surface and along the crystallographic c-axis even on non-crystalline amourphous SiO2 substrates 

[10]. This last statement has a tremendous importance and opens new possibilities for NW growth on a 

variety of nonconventional substrates of interest for applications relying on low-cost substrates. Numerous 

structures, including GaN and InN nanowires, GaN/AlGaN hetero- and quantum structures as well as 

InN/GaN core-shell structures were realized over the past years. 

The high quality of the material allowed for studying fundamental transport properties. In our work 

particular emphasis was given to the investigation of effects due to surface space charge layers. Therefore, 

we especially focused on both narrow gap (InN) and wide band gap (GaN) materials in which accumulation 

and depletion space charge layers are present at the surface, respectively. 

The investigation of the electrical properties of GaN nanowires showed that the band-to-band photoelectric 

effect varies by orders of magnitude as a function of the nanowire diameter [4]. For these studies, single 

nanowire devices were fabricated using e-beam lithography for the preparation of metallic contacts. The 

unusual effect which we found was explained by modeling of the effect of the electron depletion region at 

the nanowire surface. Photovoltage Spectroscopy and Spectral Photoconductivity (SPC) measurements have 

been carried out to analyze the near band-edge absorption in GaN nanowires [11]. A strong diameter 

dependence of the band absorption tail was found by SPC measurements. The band-edge tailoring and its 

wire-diameter dependence can be explained by the Franz-Keldysh effect induced by the electric field at the 

wire surface. 

16


In InN nanowires in contrast to GaN the Fermi-level pinning in the conduction band induces a highly 

conductive surface accumulation layer and as a result the nanowires display very high currents several orders 

of magnitude higher than in the GaN nanowires. In addition, the movement of the Fermi level within the 

conduction band results in changes of the photoluminescence (PL) peak position. Therefore, a detailed 

analysis of the PL spectra has been used to determine intrinsic properties of InN nanowires such as band gap 

and electron concentration and to proof the existence of a surface accumulation layer [12]. InN nanowires 

additionally represent ideal systems for the observation of ballistic transport and quantum effects ona 

nanometer scale [13]. 

3 – Conclusion 

The effect of surface Fermi-level pinning and its interplay with the nanowire dimensions on the 

recombination behavior of electron hole pairs in photoconductivity were investigated. The distinct transport 

properties of GaN and InN are explained by the different surface Fermi level pinning leading to surface 

depletion and accumulation for GaN and InN, respectively. Particular emphasis has been given to the 

investigation of effects due to space charge layers.The space charge could be used as a design parameter for 

novel devices concept. 

[1] A. Greytak, L. Lauhon, M. Gudiksen, and C. M. Lieber, Appl. Phys. Lett. 84, 4176 (2004). 

[2] S. Gradečak, F. Qian, Y. Li, H.-G. Park, and C. M. Lieber, Appl. Phys. Lett. 87, 173111 (2005). 

[3] Y. Huang, X. Duan, Y. Cui, L. J. Lauhon, K.-H. Kim, and C. M. Lieber, Science 294, 9, 1313 (2001). 

[4] R. Calarco, M., Marso, T. Richter, A. I. Aykanat, R. Meijers, A. v.d. Hart, T. Stoica, and H. Lüth, Nano Letters 5, 981 (2005). 

[5] A. Cavallini, L. Polenta, M. Rossi, T. Richter, M. Marso, R. Meijers, R. Calarco, and H. Lüth, Nano Letters, 6(7), 1548-1551 (2006). 

[6] R. Meijers, T. Richter, R. Calarco, T. Stoica, H.-P. Bochem, M. Marso, and H. Lüth, J. Cryst. Growth 289, 381 (2006). 

[7] T. Stoica, R. Meijers, R. Calarco, T. Richter, and H. Lüth, J. Cryst. Growth 290, 241 (2006). 

[8] R. Calarco, R. J. Meijers, R. K. Debnath, T. Stoica, E. Sutter and H. Lüth Nano Letters, 7 (8), 2248 -2251, (2007). 

[9] R. K. Debnath, R. Meijers, T. Richter, T. Stoica, R. Calarco and H. Lüth, Appl. Phys. Lett., 90, 123117 (2007). 

[10] T. Stoica, E. Sutter, R. Meijers, R. K. Debnath, R. Calarco, and H. Lüth Small 4, 751 (2008). 

[11] A. Cavallini, L. Polenta, M. Rossi, T. Stoica, R. Calarco, R. J. Meijers, T. Richter and H. Lüth Nano Letters, 7, 2166 (2007). 

[12] T. Stoica, R. Meijers, R. Calarco, T. Richter, E. Sutter, and H. Lüth,, Nano Letters, 6(7), 1541-1547 (2006). 

[13] T. Richter, C. Blömers, H. Lüth, R. Calarco, M. Indlekofer, M. Marso, and T. Schäpers, Nano Lett. 8, 2834 (2008). 

17H30-17H50 

Probing Single AlGaAs Core-Shell Nanowires by Raman Spectroscopy. 

B. Buick*1, E. Speiser1, P. Prete2, P. Paiano3, N. Lovergine3, and W. Richter1 (1 

Dipartimento di Fisica, CNISM, Universita‟ di Roma Tor Vergata, 00133 Roma, Italy. 2 IMM-CNR, Unità di Lecce, 

Via Arnesano, 73100 Lecce, Italy. 3 CNISM, and Dipartimento di Ingegneria dell‟Innovazione, Università del 

Salento, Via Arnesano, 73100 Lecce, Italy)* Corresponding author e-mail: benjamin.buick@roma2.infn.it 


Semiconductor nanowires (NWs) of III-V compounds are of central interest due to their innovative physical 

properties and due to potential applications in electronic and photo-electronic devices. Ternary nanowires are 

promising because their properties can be tailored by the stoichiometry. Furthermore, nanowires containing 

axial/ radial homo- or heterojunction are especially interesting. 


Freestanding AlGaAs NWs were grown by MOVPE by the Vapor Liquid Solid (VLS) method along the 

(111) direction on GaAs(111) substrates. Depending on the growth conditions, the nanowires show diameters 

< 100 nm or an unintetional/ intentional core-shell structure. Raman spectroscopy provides access to the 

vibrational/structural properties, carrier concentration (doping) and the material stoichiometry. 

17


Raman measurements were done with a scanning confocal micro-Raman spectrometer providing both lateral 

(


Fig. 1: Typical field emission SEM images of LSMO nanowires 

prepared using polyimide membranes with 100 nm pore size. 

The inset shows a magnified image. 

Fig. 2: SEMFE image of self-assembled. 

epitaxial LSMO monoclinic nanowires 

As a model system, La0.7Sr0.3MnO3 polycrystalline vertical nanorods in the range of 100 to 300 nm in 

lateral sizes and up to 1 µm in height have been also grown on STO and LAO single crystal substrates at 

mild temperatures (800 ºC), using a polycarbonate nanotemplate buffer layer. The nanorods suffer a 

profound transfo rmation into vertical single crystalline (La,Sr)xOy nanopyramids sitting onto a LSMO 

epitaxial wetting layer, upon strong thermal activation (1000ºC). The driving force for this outstanding 

nanostructural evolution is the minimization of the total energy of the system that is reached by reducing the 

grain boundary energy and total surface and strain relaxation energies. Finally, advanced electron 

microscopy techniques were used to highlight the complex phase separation and structural transformation 

occurring when the metastable state is overcome [2]. 

Fig. 3: SEM images of LSMO polycrystalline nanorods vertically grown on LAO substrate, 

In summary, this work establishes a method of preparing complex oxides nanostructures by sol-gel based 

polymeric precursor solution, using a totally novel version of track etched polymer directly buffering 

substrates, which is of the utmost importance and could be applied to any number of substrate thin film 

combinations. It allows nanostructuration of other functional complex oxide nanostructures; an issue that is 

widely pursed by the scientific community, to go beyond the complex and expensive top-down 

nanolithography methodologies required nowadays. 

We acknowledge the financial support from MICINN (MAT2008-01022, MAT2005-02047, MAT2006- 

26543-E, NAN2004-09133-CO3-01, Consolider NANOSELECT and FPI), Generalitat de Catalunya 

(Catalan Pla de Recerca SGR-0029 and XaRMAE), CSIC (PIF-CANNAMUS) and EU (HIPERCHEM, 

NMP4-CT2005-516858 and NESPA) for TEM facilities. 

[1] A. Carretero-Genevrier, N. Mestres, T. Puig, A. Hassini, J. Oro, A. Pomar, F. Sandiumenge, X. Obradors, E. Ferain, Adv Mater. 20, 

3672(2008). 

[2] A. Carretero-Genevrier, J. Gázquez, T. Puig, N. Mestres, F. Sandiumenge, X. Obradors, and E. Ferain , Adv. Funct. Mater., 

10.1002/adfm.200901971(2009). 

19


18H10-18H30 

Self-organized Ce1-xGdxO2-y Nanowire Networks with Ultrafast 

Coarsening resulting from Anisotropic Strain. 

M. Gibert, P. Abellán, F. Sandiumenge, T. Puig, X. Obradors (Institut de Ciència de 

Materials de Barcelona, ICMAB-CSIC, 08193 Bellaterra, Catalonia, Spain) mgibert@icmab.es 


Assembling arrays of ordered nanowires is a key objective for many of their potential applications. However, 

a lack of understanding and control of the nanowires‟ growth mechanisms limits their thorough development. 

In this work, we report a new path towards self-organized epitaxial nanowires networks produced by high 

throughput solution methods. 


Fine control of interfacial energy through growth conditions enables us to select the crystallographic 

orientation of Ce1-xGdxO2-y (CGO) nanostructures on perovskite substrates (i.e., LaAlO3 (LAO)), 

providing us with a powerful tool to study the formation of islands with different degree of lateral aspect 

ratio c. Self-organized and stable uniform square-based nanopyramids form when the crystallographic 

orientation (001)CGO[110]||(001)LAO[100] is promoted [1]. In contrast, anisotropically strained CGO 

nanowires are generated when the (011) orientation is grown on the (001) surface of the LAO single-crystals. 

As a result, self-organized anisotropic nanostructures with aspect ratios above ~100 oriented along two 

mutually orthogonal axes are obtained leading to labyrinthine networks. Detailed experimental analyses and 

thermodynamic modeling has enabled us to identify two requisites to generate such epitaxial nanowires; a 

thermodynamic driving force for an unrestricted elongated equilibrium island shape, and an ultrafast 

effective growth rate. Ultrafast coarsening (~60 nm min-1) derives from Ostwald ripening and anisotropic 

dynamic coalescence, both promoted by strain-driven attractive nanowire interaction, and from fast 

recrystallization enabled by rapid atomic diffusion associated to a high concentration of oxygen vacancies. 


Hence, we propose a new and high throughput approach to generate self-organized nanowire templates, 

which has a wide potential for many materials and functionalities. The thermodynamic origin and the kinetic 

mechanisms enabling their formation are fully scrutinized. 

[1] Gibert, M. et al., Adv.Materials 19, 3937 (2007). 

20


18H30-18H50 

Fabrication of Ordered Silicon Nanowires by Self-Assembling and Metal 

Assisted Etching. 

L. Boarino1, E. Enrico1, N. De Leo1, F. Celegato1, P. Tiberto1, E. Lepore2 and N. 

Pugno2 (1 NanoFacility Piemonte, Electromagnetism Division, Istituto Nazionale di Ricerca Metrologica, 

Stradadelle Cacce 91 - 10135 Turin, Italy; E-mail: l.boarino@inrim.it; Tel: +39 (11) 39196402 Dept. of Structural 

and Geotechnical Eng., Politecnico di Torino, C.so Duca degli Abruzzi 24 - 10148Turin, Italy) 


The field of silicon nanowires (SiNWs) saw, in the last years, a real boom in the number and quality of 

publications. A part the basic research, investigating the most fundamental properties like electron transport1 

and mechanics2, several fields of application can take advantage from silicon nanowires, like energy, with 

photovoltaic devices of new generation3, energy harvesting by vibrations4 and new adhesives5. The recent 

development of the self-catalytic electroless etching in presence of metals6, give us a new degree of freedom 

in nanofabrication, because this kind of etching is only slightly dependent on silicon wafer doping and from 

solutions and etching conditions7 but mainly from metal distribution, thickness or patterning at the silicon 

surface. We used these different conditions, from continuous thin silver films deposited by different methods 

and with different thickness to nanopatterned thin films by means of self-assembled monolayers of 

polystyrene nanospheres to obtain forests of silicon nanowires with different spatial density, distribution and 

order. A preliminary analysis of contact angles is provided, since ordered arrays of SiNWs are interesting 

systems for the study and fabrication of self-cleaning surfaces and new types of adhesives. 


Silicon wafer by MEMC Corporation, 20-30 Ohm cm have been cleaned by RCA for one hour to 

remove organic contamination, and then silver thin films of different thicknesses (20, 30 and 40 nm) have 

been thermally evaporated and sputtered. On one serie of samples, after SEM inspection by a FEI Inspect F, 

to check thin film quality and adhesion, MAE etching has been performed with no patterning. On another 

serie, a large 2D crystal of Sigma Aldrich 500 nm polystyrene nanospheres has been selfassembled and 

applied. Sputter etching by Ar ions is then performed, with times ranging from 1 to 2 minutes (processing 

steps shown in Fig. 2), to obtain a silver film with regular indentation favouring the extrusion of silicon 

nanowires in the following etching step. At this point Metal Assisted Etching has been performed for both 

the series of samples for 60 seconds at 60° C in a solution of HF:H2O2:H2O, 22%:9%:69% in volume. After 

rinsing in water, the final SEM analysis reveals for the continuous silver thin films of different thickness, the 

expected disordered forest of silicon nanowires. What is interesting is the change in wire diameter and spatial 

distribution as a function of the silver thickness. Preliminary contact angle measurements confirmed contact 

angles close to 150°, in the regime of superhydrophobicity8. The serie patterned with nanospheres and then 

sputter-etched, shows large ordered areas, characterized by the memory of the spheres distributions, with 

nanopillars and nanowires depending on the time of etching and form the efficiency of the local reaction. 

Figure 2. Processing steps for SiNWs by MAE and PSNS self assembling 

21



In this work ordered nanopillars and nanowires by MAE and PSNS self-assembling has been obtained with 

good uniformity on large area. A preliminary study of contact angles reveals superhydrophobicity of such a 

surface. 

Acknowledgements 

This work has been performed at NanoFacility Piemonte, INRiM, a laboratory supported by Compagnia di 

San Paolo. 

1 Y. Li, F. Qian, J. Xiang et al., Materials Today 9 (10), 18-27 (2006). 

2 M. Menon, D. Srivastava, I. Ponomareva et al., Physical Review B 70 (12) (2004). 

3 T. Bozhi, X. Zheng, T. J. Kempa, Y. Fang, N. Yu, G. Yu, J. Huang, C. M. Lieber, Nature 449 (7164), 

885 - 889 (2007). 

4 L. Qu, Y. Li, H. Zhang, Y. Huang, X. Duan, Nano Letters 9 ( (12)), 4539-4543 (2009). 

5 B. J. Alemn, K. E. Fischer, S. L. Tao, R. H. Daniels, E. M. Li, M. D. Bnger, G. Nagaraj, P. Singh, A. 

Zettl, T. A. Desai, Nano Letters 9 ( (2)), 716-720 (2009). 

6. S. Chattopadhyay, Xiuling Li, and P. W. Bohn, Journal of Applied Physics 91 (9), 6134-6140 (2002). 

7. S. Bastide, C. Chartier, and C. Levy-Clement, Electrochimica Acta 53, 5509–5516 (2008). 

8. G. Piret, Y. Coffinier, C. Roux, O. Melnyk, R. Boukherroub; Langmuir 24, 1670 (2008) 

18H50-19H10 

Synthesis of cation-intercalated titanate nanobelts. 

Lei Miao 1, Sakae Tanemura2,1*, Rong Huang3, Chenyan Liu1, C.M.Huang1, Gang 

Xu1 (1. Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, No.2 Nengyuan Road, 

Wushan, Tianhe district, Guangzhou, 510640, P.R.China; 2. Japan Fine Ceramic Center, 2-4-1 Mutsuno, Atsuta-ku, 

Nagoya 456-8587, Japan; 3. Key Laboratory of Polarized Materials and Devices, Ministry of Education, East China 

Normal University, Shanghai 200062, China). miaolei@ms.giec.ac.cn, *tanemura-sakae@jfcc.or.jp, 

rhuang@ee.ecnu.edu.cn 


Protonated-titanate nanostructured materials have attracted increasing attention owing to their potential 

applications on water photo-decomposition, photocatalysis, hydrogen storage, sensors, and batteries, 

electrochromism, photoluminescence, dye-sensitized solar cells, as well as active ion-exchange/ intercalation 

reaction. In order to explore more excellent performance, it is highly desirable to control the lectric and 

optical properties by different metal ion intercalation. Pure and cations (Li+, Sn2+, Al3+, Fe3+) intercalated 

titanate nanobelts with high aspect ratios, good crystal quality, large specific surface areas and uniform 

dispersion, were synthesized by alkaline hydrothermal treatment of ground TiO2 powdersfollowed by special 

washing-treatment process. The morphology, composition, crystal structure, and electrical conductivity of 

the obtained nanobelts are studied in this work. 


The ground TiO2 powders were hydrothermally treated using 10 M NaOH solution at 150 oC for 40 hrs in a 

stainless Teflon-lined autoclave. Details of the fabrication process were already reported elsewhere [1-2]. 

Cation-exchange reactions were carried out in aqueous ammonia solution with Li+, Sn2+, Al3+, and Fe3+ 

respectively for 4 kinds of intercalated samples, because of the stability of titanate nanobelts in basic solution 

and the stabilization of these substituting ions by complication with ammonia. In a typical process, 10 g of 

salts (SnCl2·2H2O, Al(NO3)·9H2O, LiCl and FeCl3·2H2O, (Alfa Aesar chemicals company), of the 

22


corresponding ions were dissolved in 25 ml deionized water followed by adding analytical ammonia solution 

drop by drop to form clear solutions. The titanate nanobelts were then dispersed in the respective solutions 

and stirred for 20 hrs to assure sufficient dispersion and diffusion. Then, products were carefully washed 

with dilute ammonia and deionized water by several times to avoid physical adsorption of the substituting 

ions on the surface of the titanate nanobelts. At last the nanobelts were washed by ethanol and dried at 80oC 

for 4hrs. 


Pure and cation intercalated titanate nanobelts with high aspect ratio (about 250) were confirmed by TEM 

observation. XRD patterns showed no crystallized Li, Sn, Al and Fe or their oxides beside typical titanate 

peaks. EDS spectra confirmed the existence of Sn, Al and Fe element in the products, respectively. The 

electrical resistivity of the typical as-prepared Al-intercalated nanobelts ranged from 0.15-26 ohm·m in the 

temperature range of 382-754oC. 

References 

(1) Miao, L.; Ina, Y.; Tanemura, S.; Jiang, T.; Tanemura, M.; Kaneko, K.; Toh, S.; Mori, Y. Surf. Sci.2007, 601, 2792. 

(2) Miao, L.; Tanemura, S.; 

23


Room Port-Pin 

17H00-17H30 

Applications of Nano-assembly in Neuroscience: From Multimodal 

Imaging to Regenerative Scaffolds. 

K.Swaminathan Iyer1* Cameron W. Evans1,2, Dominic Ho1, Jie Fang1, Melissa J. 

Latter1, Colin L. Raston1, Alan R. Harvey3,  Sarah A. Dunlop2, Melinda 

Fitzgerald2 (Centre for Strategic Nano-fabrication, School of Biomedical, Biomolecular and Chemical 

Sciences, The University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia; 2 Experimental 

and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, 35 Stirling 

Highway, Crawley WA 6009, Australia; 3 School of Anatomy and Human BiologyThe University of Western 

Australia, 35 Stirling Highway, Crawley WA 6009, Australia) +61 8 6488 4470, 

swaminatha.iyer@student.uwa.edu.au 

Neurotrauma is defined as a “traumatic injury of the central nervous system (CNS)”. Such traumatic CNS 

can be attained as a result of traumatic brain injury (TBI) and spinal cord injury (SCI) . The consequences of 

such injuries in victims are usually dire and will usually lead to disability. This disability can range from 

paralysis and life time loss of function e.g. loss of vision to death. Injuries from neurotrauma can occur via 

both the initial traumatic impact and the secondary injury cascade which results thereafter. Following the 

initial impact, the neurons at the injury site undergo primary injury and die via necrotic cell death. 

Furthermore, functionally important reactive changes in the supporting glial cells e.g. astrocytes and myelin 

producing oligodendrocytes occurs. Neurons close to the injury site are axotomised and undergo a slower 

form of cell death termed “apoptosis”. Cell death occurring as a result of both primary and secondary injury 

is difficult to prevent, however, some neurons do survive these events. Hence, promoting axon regeneration 

and neuroprotection remains a highly challenging obstacle and is also the key to regaining functional 

recovery. 

Application of nanotechnology in neuroscience is an emerging field with great potential.For example, 

nanotechnology has been used to examine diverse aspects such as glycine receptor function, drug delivery 

across the blood brain barrier5 and to provide micropatterns to control neuronal growth and connectivity. 

Recent exciting advances are also being made in neuroprotection (preventing cell death of neurons and 

supporting glia) and neuroregeneration (promoting axon regrowth) after CNS injury which build on 

extensive work at a “macro” level using synthetic, natural and biological materials for drug delivery 

scaffolds. 

The presentation will focus on the synthesis of various magnetic fluorescent nano-hybrid systems using 

polymeric, inorganic and a macromolecular assembly approach for multimodal imaging and towards targeted 

drug delivery. We will also present the use of self-assembling RADA16 peptide scaffolds as platforms for 

regeneration. We will explore the applications of these novel materials as potential vehicles for 

neuroprotection and neuroregeneration. 

Acknowledgment 

Financial support of this work was provided by the Australian Research Council. We acknowledge the 

facilities, scientific and technical assistance of the Australian Microscopy & Microanalysis Research Facility 

at the Centre for Microscopy, Characterisation & Analysis, The University of Western Australia. 

24


17H30-17H50 

Functionalized Magnetic Nanomaterials for Clinical Bio-separation. 

Chang (Korea Institute of Ceramic Engineering and technology, 233-5 Gasan-dong, Guemcheon-gu, Seoul, 153- 

801, Korea) E-mail: jhchang@kicet.re.kr 


In this work, we developed the molecularly assembled magnetic nanomaterials such as silica coated 

magnetic nanoparticles and magnetic mesoporous silica particles for the DNA/protein separation at the 

different pH conditions. Onto the materials, the monolayers of organosilanes were grafted to enforce the 

covalent bonding and to capture the target proteins as the anchored probes. Protein detection with 

organosilanes assembled silica-coated magnetic nanoparticles was achieved by UV-Vis. spectro-photometry 

from the supernantant solution, and the additional morphology, magnetic moment, electrostatic interaction 

and composition of the particles were characterized by XRD, FT-IR, TEM, VSM, Zeta potential, BET and 

Electrophoresis. 


The effect of nanoparticle‟s size and the surface‟s hydrophilicity change were studied for magnetic 

separation process, in which the optimum efficiency was explored via the function of the functionality, the 

amount of the nanoparticles used, and the concentration of salt. The biomolecular adsorption yields were 

high in terms of the amount of functionalized nanoparticles used, and the average particle size was 

calculated. The adsorption efficiency of functionalized nanoparticles was the 4-5 times (80-100%) higher 

compared to silica-coated nanoparticles only (10-20%). biomolecular desorption efficiency showed an 

optimum level of over 0.7 M of the NaCl concentration. To elucidate the agglomeration of nanoparticles 

after electrostatic interaction, the Guinier plots were calculated from small angle X-ray diffractions in a 

comparison of the results of electron diffraction TEM, and confocal laser scanning microscopy. Additionally, 

the direct separation of human genomic DNA was achieved from human saliva and whole blood with high 

efficiency. 


This preliminary study could enable the design and construction of an automatic system with highthroughput 

biomolecular purification with functionalized magnetic nanoparticles, and would be applied for 

clinical diagnoses and proteins/enzymes recognition processes using the appropriate surface modification 

technique. 

17H50-18H10 

Micropatterned poly-acrylamid gels for colloids self assembly and bioassays. 

Qihao He 1,2 , Claire Millot, Serge Mazères, Laurence Salomé, Aurélien Bancaud 1,2 ( 1 

CNRS ; LAAS ; 7, avenue du Colonel Roche, F-31077 Toulouse, France 2 Université de Toulouse ; UPS, INSA, INP, ISAE 

; LAAS-CNRS : F-31077 Toulouse, France) 

The library of nano-objects, such as nano-particles or nano-wires, with exquisitely defined functions for 

biology, electronics or plasmonic applications is continuously growing, and these new technological tools are 

bound to play an essential role in the development of new nanosystems. Yet, the integration of nano-objects 

remains a technical challenge that usually involves the development of bottom-up fabrication strategies. In 

25


pioneering studies, it was for instance proposed to disperse colloids in water droplets, and take advantage of 

the drying process that spontaneously organizes particles along ring-like patterns (1). This technique is 

however inadequate to obtain complex patterns, and significant improvements were obtained using 

hydrophobic polymeric micro or nano-patterned templates, on which a receding meniscus is applied to direct 

the assembly of micro and nanoparticles (2). 

In the report, we propose a novel approach to direct the assembly of micro and nano-particles on solid 

supports. Our method is based on the fabrication of patterned poly-acrylamid (pAM) hydrogels, which are 

covalently attached to silanized glass or silicon substrates. A patterned silicon substrate is laid on top of the 

gel during its formation, so that the reticulated structure is imprinted with structural patterns. The gel is 

initially enriched in water that evaporates, leading to the formation of polymeric structures typically 100- 

1000 nm in height and 10-50 µm in width. 

We demonstrate that micro and nano-particles spanning 3 orders of magnitude in size (10 nm – 10 µm) 

spontaneously accumulate along the gel patterns. Directed assembly occurs in one single step over large 

surfaces of ~cm 2 , it is directed by hydrodynamics, and it does not require any external manipulation. 

Interestingly, the dynamics of this directed assembly process could be characterized using fluorescence 

microscopy (data not shown), showing that water meniscus recede along the patterns imprinted on the 

hydrogel, and direct the assembly of particles along the motifs. 

We then assessed the yield of our technology by measuring the number of particles captured along linear 

motifs vs. the total number of particles by fluorescence microscopy. This analysis showed that large density 

particles fail to assemble along the patterns because sedimentation is faster than hydrodynamics assembly. 

Our method is particularly efficient for organizing nanoparticles along complex motifs, as inferred from the 

distribution of particles on square-shaped or eye-shaped patterns. In addition, hydrogels can be used as 

sacrificial layers using oxygen plasma etching, which selectively removes organic compounds, such as 

acrylamid. Gold colloids remain intact after this process, leaving a template readily adapted to perform a 

second round of self-assembly. 

Finally, our technology is readily adapted to bio-assays. Indeed, patterned surfaces with gold colloids can be 

used to organize biomolecules such as DNA using thiol chemistry. In addition, we were able to chemically 

functionalize our hydrogels to make them suitable for cell culture. Taken together, we show that polyacrylamid 

hydrogels are versatile materials for bio-assays and directed assembly. 

(1) Deegan et al., Nature 389, 827 (1997) 

(2) Malaquin et al., Langmuir, 23, 11513 (2007) 

18H10-18H30 

Quantum Confinement approach for the self-assembly process of peptide and 

proteins structures. 

Nadav Amdursky, †, ‡ Ehud Gazit, † and Gil Rosenman ‡ .(†Department of Molecular Microbiology 

and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978, 

Israel‡Department of Electrical Engineering-Physical Electronics, School of Engineering, Tel Aviv University, Tel 

Aviv, 69978, Israel) 

Peptide nanostructures, made by a self-assembly process of short peptide building blocks, represent a novel 

class of bio-inspired nanostructural materials. The inspiration for the studied peptide building-blocks is from 

the core recognition motif of the Alzheimer's disease, the diphenylalanine element. The dipeptide, which 

composed from two phenylalanine residues (FF), can self-assemble into peptide nanotubes (PNT). This 

26


exceptional self-assembly process possesses interesting properties. As for now, their unique properties 

contain high stability to heat and solvents, high rigidity and supercapacitance properties. 

In our studies we report for the first time in the bio-organic world on the direct observation of quantum 

confined nanocrystalline structure at various peptide nanostructures. These highly ordered building blocks of 

the structures have been observed from optical studies where pronounced quantum confinement (QC) and 

photoluminescence (PL), which results in an intense blue emission, have been revealed. We found a step-like 

optical absorption behavior, which is a distinguished feature of 2D-QC, and a spike-like behavior, which is a 

feature of 0D-QC. By calculations we have estimated the dimension of those crystalline regions to be at the 

order of only ~1 nm, a size that is most difficult to achieve at the inorganic world using common deposition 

techniques. These data directly indicates on the presence of fine crystalline structure at the PNT and allows 

relating these PNT to self-assembly ceramic-like nanostructural bio-inspired material. By following the 

formation of the exciton we could follow the self-assembly process of the structures. Our new findings of 

blue emission from the PNT may result in a peptide-based luminescence device, such as light emitting diode 

(LED) or laser. 

The studied peptide nanostructures were being inspired by motifs from amyloid proteins. This inspiration 

promoted us to explore also the self-assembly process of amyloid proteins. We have found that the selfassembly 

process of amyloid fibrils is also characterized with the formation of nano crystalline regions and 

exhibit the formation of an exciton and QC structures. 

18H30-18H50 

Creating biofibre-noble metal nanocomposites - an in situ sputter deposition 

investigation. 

Stephan V. Roth1,*, Volker Körstgens2, Kai Schlage1, Sebastien Couet1,3, Ezzeldin 

Metwalli2, Ralf Röhlsberger1, Rainer Gehrke1, Peter Müller-Buschbaum2 

(1HASYLAB-DESY, Notkestr. 85, D-22607 Hamburg, Germany; 2TU-Muenchen, Physik-Department Lehrstuhl 

E13, Garching, Germany; 3K.U. Leuven, Afdeling Kern- en Stralingsfysica, 3001 Heverlee, 

Belgium)*stephan.roth@desy.de 


Polymer-metal nanocomposites are used in many areas of sensor techniques, information technology and 

biotechnology [1]. The creation of nanocomposites using self-assembly during solution casting and sputter 

deposition are one of the most widely used methods [2,3]. Todays reduction of structural sizes for many 

sensor-type and information devices based on nanocomposite materials creates a need for investigating the 

nanocomposite's structure in such a restricted geometry [1]. Typically, these devices display a flat geometry. 

However, using aligned cylindrical, wire- or stripe-like arrays of nanoparticles enables to install plasmon 

waveguide devices which allow for guiding electromagnetic energy below the diffraction limit of light [3]. 


We explore in-situ the self-assembly of metal nanoparticles on curved, flexible biopolymeric fibers using 

grazing incidence small angle x-ray scattering (GISAXS) in combination with in-situ sputter deposition, 

following the same route used to coat flat nanostructured polymer blends [4]. This fiber-metal 

nanocomposite acts as a model system for many industrial applications, like anti-counterfeiting and cosmetic 

products, as well. 

27



We observe a well-defined growth of Au nanoparticles on the curved fiber surface. Starting from nucleation, 

the Au nanoparticles self-assemble to nm-sized clusters. Finally a coalescent layer occurs on the biofiber 

surface. One future application of this nanocomposite material might indeed be as plasmonic waveguides 

based on a highly flexible substrate. 

[1] M. Wolkenhauer et al., Appl. Phys. Lett. 89, 054101 (2006) 

[2]S. V. Roth et al., J. Phys.: Condens. Matter 21, 264012 (2009) 

[3] S. Maier et al., Nature Mat. 2, 229 (2003) 

[4] E. Metwalli et al., Langmuir 24, 4265 (2008) 

18H50-19H10 

Toward multifunctional energetic materials nanostructuration through DNA 

directed nanoparticles self assembly. 

F. Severac, C.Rossi, A.Bancaud, A.Esteve (LAAS-CNRS - 7, avenue du Colonel Roche 31077 

Toulouse Cedex 4 FRANCE.) fseverac@laas.fr – rossi@laas.fr – abancaud@laas.fr - aesteve@laas.fr 


Energetic materials (EMs) are substances that store chemical energy which can be released under a stimulus. 

They can be used in many applications such as military, health, spatial… In this context, Al/CuO couple is 

interesting because of its high potential energy and compatibility with MEMS technologies. At the 

nanoscale, the performances of these materials increase significantly but are difficult to control, thus, a 

bottom-up approach through DNA directed Al and CuO nanoparticles self assembly is a good way to realize 

multifunctional nanoenergetic materials with controlled formulation. 


In this work, the ability to create crystalline aggregates of Al and CuO nanoparticles (nAl and nCuO) from 

the bottom up is studied. Several nAl and nCuO functionalization strategies are investigated in order to 

connect modified single-stranded DNA (ssDNA) oligomers on surface: Thiol affinity, biotin-streptavidin 

binding and amide link. Nanoparticles are then assembled using hybridization between ssDNA grafted on 

their surface, thus, small aggregates of nAl and nCuO are achieved. 

The controlled self assembly of nanoparticles will allow us to study with accuracy the effect of 

nanoenergetic materials formulation on performances: ignition point, stability, energy... 


Al and CuO nanoparticles aggregates realized through DNA directed nanoparticles self assembly will be 

presented. Next step is a first step toward nanoenergetic materials with well defined properties and their 

integration in future MEMS devices. 

28

P R O G R A M TUESDAY, JUNE 29 N A N O S E A 2 0 1 0 

Tuesday, June 29 

Session 4 

Room Calendal 

Near Field Microscopy (Chairman: Teichert) 

8H30-9h10 

HILLENBRAND (Nanooptics Group, CIC nanoGUNE, 20018 Donostia - San Sebastian, Spain) 

IR and THz near-field nanoscopy for characterizing nanoscale materials and devices 

9H10-9H30 BARTH (CINaM - CNRS, Campus de Luminy, Case 913, 13288 Marseille Cedex 09) 

The Suzuki surface as a template for nano-objects: An atomic force microscopy 

study 

9H30-9H50 PALLEAU (LPCNO, INSA, Département Génie Physique 135 avenue de Rangueil 31077 Toulouse Cedex 4) 

Electrostatic assembly of colloidal nanoparticles by AFM nanoxerography 

9H50-10H10 

BASSANI (1. Institut Matériaux Microélectronique Nanosciences de Provence, UMR CNRS 6242, Avenue 

Escadrille Normandie-Niemen - Case 142, F-13397 Marseille Cedex 20, France.2. Institut des Nanotechnologies de 

Lyon, UMR CNRS5270, Université de Lyon, Institut National des Sciences Appliquées de Lyon, Bât. Blaise Pascal, 

20, avenue Albert Einstein - 69621 Villeurbanne Cedex, France") 

Electron charging and discharging of Ge nanocrystals probed by Kelvin probe force 

and electrostatic force microscopies 

10H10-10H30 

ZABALETA (1 Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Barcelona, Spain; 2 Instituto de 

Ciencia de Materiales de Madrid, ICMM-CSIC, Madrid, Spain; 3 Lawrence Berkeley National Laboratory, 

Berkeley, California,USA 4CEMES-CNRS, Toulouse, France) 

Chemically Grown La0.7Sr0.3MnO3/Single Crystal Heteroepitaxies 

10H30-11H 

11H00-12H30 

Coffee Break 

Presentations : Exhibitors and Posters 

(Chairpersons : BERBEZIER / DE CRESCENZI) 

12H30 - 16H30 


29


Session 5 

Room Calendal 

Local Chemical and Structural Characterization 

(Chairman: Hillenbrand) 

16H30-17H00 

BLAVETTE (Groupe de Physique des Matériaux (UMR CNRS 6634), UFR Sciences et Techniques, Avenue 

de l'Universite - B.P. 12 76801 SAINT ETIENNE DU ROUVRAY CEDEX FRANCE * Institut Universitaire de 

France+ IM2NP, Marseille) 

Atom Probe Tomography and Nanosciences 

17H00-17H20 

CHEYNET (1SIMAP-PHEMA - CNRS Université Grenoble – France 2IM2NP - CNRS Université Marseille 

Saint Jérôme - France 3FEI company Eidendhoven – Neederland 4LASIR Université Scientifique et Technologique 

de Lille – France) 

Advanced SEM and TEM investigations of individual and self-assembled colloidal 

PbSe nanocrystals. 

17H20-17H40 

DAU (1 Centre Interdisciplinaire de Nanoscience de Marseille (CINaM-CNRS), Aix-Marseille Université, 

Campus de Luminy, case 913, 13288 Marseille cedex 09, France; 2 IM2NP-CNRS, Aix-Marseille Université, case 

142, 13397 Marseille cedex 20, France) 

Overgrowth of Ge on Mn5Ge3/Ge heterostructures 

17H40-18H00 

ESCOUBAS (1 Aix-Marseille Université, IM2NP; 2 CNRS, IM2NP UMR 6242, Faculté des Sciences et 

Techniques, Campus de Saint-Jérôme, Avenue Escadrille Normandie Niemen, Case 142, 13397 Marseille Cedex, 

France; 3 ST Microelectronics, 850 rue Jean Monnet, 38920 Crolles, France) 

Assessing mechanical strain at the nanometer scale induced in silicon channel by 

periodic gate lines arrays through high resolution X-ray diffraction and modeling 

18H00-18H20 

BUFFET (1HASYLAB-DESY, Notkestr. 85, D-22607 Hamburg, Germany; 2TU-Muenchen, Physik- 

Department Lehrstuhl E13, Garching, Germany) 

Airbrush-spray deposition of colloidal polymer film investigated by GISAXS 

18H30-20H30 

Posters P1 and Wine Tasting 

30


Tuesday, June 29 

Session 6 

Room Port-Pin 

Si based Nanostructures (Chairman: Le Thanh) 

8H30-9h10 

ROWELL (1 National Research Council of Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada; 

2IM2NP, CNRS – Univ. Aix Marseille, Campus St. Jérôme, Case 142, 13397 Marseille CEDEX 20, France ; 

3LMEN, Case 15, UFR Sciences, Université de Reims, Champagne-Ardenne, 51687 Reims Cedex 2, France ; 4 

Univ. Di Roma 2 Tor Vergata, Via della Ricerca Scientifica , Roma, Italy Uni Tor Vergata; 5 LPSCE, Faculté des 

Sciences de Monastir, Uni. Monastir, Avenue de l'environnement 5019 Monastir, Tunisia) 

Electrical, optical and structural properties of self-organized Ge nanocrystals. 

9H10-9H30 

VANACORE (1Dipartimento di Fisica, Politecnico di Milano, P.zza Leonardo da Vinci, 32-20133 Milan, Italy 

2L-NESS, Dipartimento di Fisica del Politecnico di Milano, Via Anzani 52, I-22100, Como, Italy 3Dipartimento di 

Scienza dei Materiali, and L-NESS, Università di Milano-Bicocca, via Cozzi 53, I-20125 Milano, Italy) 

Epitaxial SiGe self-assembled island growth by Surface Thermal Diffusion: shape 

transition, intermixing and strain relaxation. 

9H30-9H50 

GRYDLIK (Institute of Semiconductor and Solid State Physics, Johannes Kepler University, Linz) 

Exploiting the interface between randomly nucleated and ordered dots for unrolling 

SiGe/Si dot properties on a micrometer scale. 

9H50-10H10 

LU (1. Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark; 2. Department 

of Physics and Nanotechnology, Aalborg University, DK-9220 Aalborg Ø, Denmark) 

Characteristic interaction distance between Si nanodots and Er3+ ions in welldefined 

multilayer films. 

10H10-10H30 MARCUS (1 Institut de Ciencia de Materials de Barcelona CSIC, Esfera UAB, 08193 Bellaterra, Spain 2 

IM2NP, CNRS – Univ. Aix Marseille, Campus St. Jérôme, Case 142, 13397 Marseille CEDEX 20,France 3 Orsay 

Physics, 95 Avenue des Monts Auréliens - ZA Saint-Charles - 13710 Fuveau, France) 

Self assembled Ge nanostructures grown on FIB nanopatterned Si substrates 

10H30-11H 

11H00-12H30 

12H30 - 16H30 


Poster Session Room Calendal 


31


Session 7 

Room Port-Pin 

Nanotechnology (Chairman: Bensahel) 

17H00-17H20 FROMHERZ (1 Institute of Semiconductor and Solid State Physics, University of Linz, 4040 Linz, Austria 2 

Functional Surfaces and Nanostructures, Profactor GmbH, 4407 Steyr, Austria) 

Pit-patterning by UV nanoimprint lithography for the site-controlled self-assembly 

of highly-uniform Si/Ge islands 

17H20-17H40 

GONCHAROV 1) A.F. Ioffe Physico-Technical Institute,St. Petersburg. 2) Department of Physics of St. 

Petersburg University,198505, St. Petersburg, Russia; 3) New Zealand Institute of Advanced Study, Massey 

University Albany campus, Auckland, New Zealand. 3) New Zealand Institute of Advanced Study, 

Massey University Albany campus, Auckland, New Zealand. 4) Department of Physics of St. Petersburg University, 

St. Petersburg, Russia. 

Transport properties of junctions and lattices via solvable models 

17H40-18H00 

MEDVID (1Riga Technical University, 14 Azenes Str., Riga, LV-1048, Latvia, 2Universitat Stuttgart, 

Pfaffenwaldring 47, 70569 Stuttgart, Germany,3Institute of Semiconductor Physics National Academy of Science of 

Ukraine, 45 Pr.Nauki, 252650, Kyiv-28, Ukraine) 

Nano-cones Formation on a Surface of Si1-xGex Layers by Laser Radiation 

18H00-18H20 

GROJO (1National Research Council of Canada, Steacie Institute for Molecular Sciences, Ottawa, Canada 2LP3 

–UMR 6182, CNRS-Univ. Méditerranée, Marseille, France 3University of Ottawa, Ottawa, Ontario, Canada 

4Kansas State University, 2012 Durland Hall, Manhattan, Kansas, USA) 

High refractive index modification inside Si02 by femtosecond laser created selfordered 

planar nanostructures 

18H20-18H40 

PREZIOS (1Dipartimento di Fisica, Università dell‟Aquila, gc-LNGS INFN, Via Vetoio, 67100, L‟Aquila, Italy 

2Dip. di Ingegneria Elettronica, Univ. degli studi di Roma “Tor Vergata”, Viale Politecnico 1, 00133 Roma, Italy) 

Fabrication of an IR emitting ErQ3-based distributed feedback laser by X-ray 

Interference Lithography. 

18H30-20H30 

Poster P2 and Wine Testing 

32


Session Poster P1-P2 

AOUASSA 

Porous-Si / Ge heterostructures for photovoltaic applications. 

mansour.aouassa@im2np.fr 

BARIS 

2D Self-assembled supramolecular network on a Si(111)-B surface. 

bbaris@univ-fcomte.fr 

BOARINO 

Nanopatterned thin films for magnetic application by self-assembling of polystyrene 

nanospheres. 

boarino@inrim.it 

BREHM 

Narrow photoluminescence emission of Ge islands grown on pit-patterned Si(001) 

substrates at various temperatures. 

florian.hackl@students.jku.at 

CHANG 

Hydrophobic partitioning approach to efficient protein separation with magnetic 

nanoparticles. 

jhchang@kicet.re.kr 

CHERIOUX 

Complete Supramolecular Self-Assembled Adlayer on a Silicon Surface at Room 

Temperature. 

frederic.cherioux@femto-st.fr 

D'ANGELO3C 

SiC nanocrystals formation at the SiO2 / Si interface. 

dangelo@insp.jussieu.fr 

DAU 

Molecular beam epitaxial growth of Ge nanowires on Si(111) substrates. 

lethanh@cinam.univ-mrs.fr 

DEPADOVA 

Structural and magnetic properties of SiGe clusters Mn-doped grown on Si(001). 

paola.depadova@artov.ism.cnr.it 

DIBI 

A new gate stack double diffusion MOSFET design to improve the electrical 

performances for power applications. 

faycaldzdz@hotmail.com 

DIRANI 

Photopatterning of metal oxides nanostructures by DUV lithography. 

ali.dirani@uha.fr 

33


DONNADIEU 

Strain fields from transmission electron microscopy images in Ge nanopyramids on 

Si substrate. 

patricia.donnadieu@simap.grenoble-inp.fr 

GIRI 

Microstructure and optical properties of freestanding Si nanocrystals. 

giri@iitg.ernet.in 

GOMES 

Si substrate nanostructuring using mass-filtered focused ion beam with Si and Au 

ions. 

elise.gomes@im2np.fr 

GOSSET 

Electron spin resonance and spectrophotometric studies of free radical reactions and 

cellular oxidative damages induced by tetravalent and trivalent cerium salts and 

cerium nanoparticles: evidence that oxidative stress is unrelated to a direct ceriuminduced 

Fenton-like chemistry. 

sylvia.pietri@univ-provence.fr 

GROJO 

Thin film nanopatterning by laser interaction with self-assembled microsphere 

monolayers. 

grojo@lp3.univ-mrs.fr 

GRYDLIK 

Inverted Ge islands in {111} faceted Si pits ¬a novel approach towards islands with 

higher aspect ratio. 

martyna.grydlik@jku.at 

GUALTIERI 

Tribology and wettability of nano-machined silicon rough surfaces. 

egualtieri@unimore.it 

GUERRA 

Conditions of High Luminescence in Si/SiO2 Nanoclusters. 

robguerra@unimore.it 

HAN 

Growth of InAlAs/AlGaAs quantum dots on GaAs substrate for the 808-nm 

wavelength applications. 

hikoel@kist.re.kr 

KIM 

Linearly Polarized Light Emission from InGaN/GaN Quantum Well Structure with 

High Indium Composition. 

ek-kim@hanyang.ac.kr 

KIM 

Thermal Stability of Metal-Silicide Nanocrystals Nonvolatile Memory with Barrier 

Engineered Tunnel Layers. 

ek-kim@hanyang.ac.kr 

34


LEROUX 

Built-in electric field screening and radiative efficiency of ensembles of 

(Al,Ga)N/GaN quantum dots and dashes. 

ml@crhea.cnrs.fr 

MAHAMDI 

Ellipsometric and RBS studies of SiOXNY films elaborated by PECVD. 

ra_mahamdi@yahoo.fr 

MYCHKO 

Influence of nano-hilss formed by laser radiation on photoconductivity of CdZnTe. 

amychko@latnet.lv 

PASSANANTE 

Dewetting of germanium-on-insulator thin films measured by Low Energy Electron 

Microscopy. 

passanante@cinam.univ-mrs.fr 

PECZ 

Silicon nanorods for novel solar cells. 

pecz@mfa.kfki.hu 

ROWELL 

Photoluminescence Efficiency of Self Assembled Ge Dots on porous TiO2. 

Nelson.Rowell@nrc-cnrc.gc.ca 

SAHRAEIL 

Optical Properties of Nanocrystalline CdS Thin Films Prepared by a New Chemical 

Solution Deposition Route for Application in Solar Cells as window layers. 

reza_sahrai@yahoo.com 

SARGENTIS 

A 3-D modeling of the discharging characteristics of non-volatile memories 

embedded with metallic nanoparticles. 

sargent@central.ntua.gr 

SIMION 

Surface nanostructuration role in detection of HPV using microarray technology. 

monica.simion@imt.ro 

SOUSSOU 

Numerical investigation of Si1-xGex/Si core-shell nanowire field-effect transistors. 

assawer.soussou@gmail.com 

VARLAMOVA 

The laser polarization as control parameter in self-organized nanostructures 

formation upon multi-pulse femtosecond laser ablation. 

olga.varlamova@tu-cottbus.de 

ZHANG 

Strain engineering in Si via closely stacked, site-controlled SiGe islands. 

jianjun.zhang@jku.at 

35

A B S T R A C T S TUESDAY, JUNE 29 N A N O S E A 2 0 1 0 

Room Calendal 

8H30-9h10 

IR and THz near-field nanoscopy for characterizing nanoscale materials and 

devices 

Rainer Hillenbrand (Nanooptics Group, CIC nanoGUNE, 20018 Donostia - San Sebastian, Spain) 

r.hillenbrand@nanogune.eu 

The development of novel nanoscale materials, composites and devices requires ultrahigh-resolution 

microscopy tools for characterization and mapping of local material properties and nanoscale confined light 

fields. In this talk, I will demonstrate a near-field optical microscopy technique providing a spatial resolution 

of about 10-20 nm independent of the wavelength. It is based on elastic light scattering from the probing tip 

of an atomic force microscope (scattering-type near-field optical microscopy, s-SNOM [1]). Besides an 

introduction of the technique, I will demonstrate some s-SNOM applications including infrared and terahertz 

mapping of chemical composition, free-carrier concentration in semiconductor nanodevices [2], strain fields 

and nanocracks in ceramics [3], as well as the visualization of the near-field oscillations of optical and midinfrared 

plasmonic nanoantennas [4]. 

[1] F. Keilmann and R. Hillenbrand, Philos. Trans. R. Soc. London, Ser. A 362, 739 (2004) 

[2] A. Huber, et al., Nano Lett. 8, 3766 (2008) 

[3] A. Huber, et al., Nature Nanotech. 4, 153 (2009) 

[4] M. Schnell, et al., Nature Photon. 3, 287 (2009) 

9H10-9H30 

The Suzuki surface as a template for nano-objects: An atomic force microscopy 

study. 

C. Barth, R. Peresutti, M. Gingras and C. R. Henry (CINaM - CNRS, Campus de Luminy, Case 

913, 13288 Marseille Cedex 09) barth@cinam.univ-mrs.fr 

In 1961, Kazuo Suzuki found out by X-ray diffraction experiments that a new phase is created in NaCl 

crystals if the crystals are doped with divalent impurity ions (e.g., with Cd2+ or Mg2+) [1]. In this so-called 

Suzuki phase, the positive divalent impurities and sodium vacancies are arranged in an highly ordered atomic 

lattice, which is twice as large as the one of pure NaCl. In real crystals, the Suzuki phase can be found in 

cubic precipitates, which are embedded in the NaCl matrix. Thanks to recent noncontact AFM experiments, 

the surfaces of Suzuki precipitates on NaCl(001) could be precisely characterized in ultrahigh vacuum [2-4]. 

Basically two types of surface regions exist on NaCl:Cd2+(001) [2]: surface regions of pure NaCl and 

regions of Suzuki precipitates, which cover partially the (001) surface of the crystal. It has been shown by 

atomic resolution imaging, that the precipitates are indeed embedded in the NaCl matrix and that both types 

of surface regions are atomically flat [3]. Each ionic species in the atomic 

Suzuki structure can be unambiguously identified by just imaging [3, 4]. Kelvin probe force microscopy has 

further shown, that the precipitates carry a net negative surface charge, which is due to the negative sodium 

vacancies [3]. 

Despite many attractive properties of Suzuki surfaces like the interesting nano-structuring at the nanometer 

scale and the presence of negative cation vacancies on the surface, Suzuki surfaces have not yet been used as 

a substrate surface for nano-objects like molecules or metal clusters. In this contribution the Suzuki surface 

36


will be presented and a description of the structure and morphology of Suzuki surfaces of as-UHV-cleaved 

crystals and additionally annealed crystals, which exhibit surfaces restructured by diffusion and evaporation 

processes, is given. A discussion about defects like dislocations is involved. Further, it will be discussed to 

what extend the nano-structured Suzuki surface can be used as a nano-template for molecules and metal 

nano-clusters. First-time experiments will be presented, which exemplify the nano-template effect of Suzuki 

Surfaces. 

[1] K. Suzuki, J. Phys. Soc. Jpn. 16, 67 (1961) 

[2] C. Barth and C. R. Henry, New J. Phys. 11, 043003 (2009) 

[3] C. Barth and C. R. Henry, Phys. Rev. Lett. 100, 096101 (2008) 

[4] A. S. Foster, C. Barth and C. R. Henry, Phys. Rev. Lett. 102, 256103 (2009) 

9H30-9H50 

Electrostatic assembly of colloidal nanoparticles by AFM nanoxerography. 

Etienne PALLEAU, Laurence RESSIER , Guillaume VIAU (LPCNO, INSA, Département 

Génie Physique 135 avenue de Rangueil 31077 Toulouse Cedex 4) etienne.palleau@insa-toulouse.fr, ressier@insatoulouse.fr 


Colloidal nanoparticles are promising building blocks to fabricate future nanodevices in various domains 

such as chemical and biologic sensing, electronics, optics... But their integration in functional devices 

requires their directed assembly at desired locations on substrates. 

Electrostatic nanopatterning by atomic force microscopy (AFM) is an emerging tool to tackle this 

technological challenge [1]. This so-called “AFM nanoxerography” process utilizes charged patterns 

obtained by AFM charge writing into electret thin films to generate strong electric fields above the surface 

which act, via electrostatic interactions, as self-assembly targets for any kinds of charged or polarizable 

colloids. 

We expose here the directed assembly of various colloidal nanoparticles onto charged patterns written by 

AFM into poly(methylmethacrylate) (PMMA) thin films under ambient conditions. We also investigate the 

contribution of the two electrostatic forces responsible of the selective deposition of these colloids onto 

charged patterns. 

2 – Experiments and results 

The AFM nanoxerography process is a two step method. The first step consists in AFM charge writing into 

100 nm PMMA (996 k molecular weight) thin films spin-coated on a p-doped (1016 cm-3) silicon substrate 

under ambient conditions (Fig. 1a)). The surface potentials of such charged patterns are measured by Kelvin 

Force Microscopy (KFM). The second step of the process consists in dipping the electrostatically patterned 

substrate into non polar solvents containing nanoparticles then rinsing it in fresh solvent to remove the 

loosely adsorbed nanoparticles and finally drying it in nitrogen stream (Fig. 1b)). The directed nanoparticle 

assembly is finally observed by AFM in tapping mode (Fig. 1c)). 

37


Figure 1. Principle of the AFM nanoxerography process 

The AFM ability to perform, with the same instrument, charge writing with a great flexibility of pattern 

design, high-resolution charge imaging by surface potential measurements (KFM) and topography imaging 

by tapping, is very useful for understanding and improving the nanoxerography process. 

AFM nanoxerography is a generic process since it can be used to trap any charged and/or polarizable 

colloids (nanoparticles, nanotubes [2], biomolecules [3]) on specific areas of surfaces. To illustrate this point, 

we present in this paper the directed assembly of various kinds of colloidal nanoparticles by AFM 

nanoxerography, such as 100 nm latex nanoparticles in isopropanol, 10 nm silver nanoparticles or 2-3 nm 

gold nanoparticles in hexane. 

Depending on the surface charge and the polarizability of the colloidal nanoparticles used, the 

electrophoretic (Coulomb) and dielectrophoretic forces lead to a specific attraction/repulsion on positively 

and/or negatively charged patterns. For instance, negatively charged latex nanoparticles are attracted by 

electrophoretic forces on positively charged patterns and are strongly repeled from negatively ones. Silver 

nanoparticles do not seem to carry an important effective charge but are extremely polarizable leading to 

their directed assembly on both positively and negatively charged patterns. 

We recently performed numerical simulations of KFM measurements after AFM charge writing, in 

correlation with KFM experiments [4]. These simulations allow us to quantify the strenght of the electric 

field generated by charged patterns when immersed into several solvents. These results are used to quantify 

the contribution of each electrostatic force during the immersion of the charged substrates in the different 

colloidal solutions. 


The directed assembly of various kinds of colloidal nanoparticles on specific areas of surfaces are performed 

by AFM nanoxerography. Depending on the surface charge and the polarizability of colloidal nanoparticles, 

the electrophoretic (Coulomb) and dielectrophoretic forces lead to a specific attraction/repulsion on 

positively and/or negatively charged patterns. Numerical simulations were carried out to quantify these 

electrostatic forces in various experimental conditions. 

[1] L. Ressier, E. Palleau, C. Garcia, G. Viau and B. Viallet, IEEE T Nanotech. 2009, 8 (4), 487-491 

[2] L. Seemann, A. Stemmer, and N. Naujoks, Nano. Lett. 2007, 7 (10), 3007-3012 

[3] E. Macarena Blanco, S. A. Nesbitt, M. A. Horton, and P. Mesquida, Adv. Mater, 2007, 19, 2469–2473 

[4] E. Palleau, L. Ressier, Ł. Borowik and T. Mélin, Nanotech., 2010, under submission 

38


9H50-10H10 

Electron charging and discharging of Ge nanocrystals probed by Kelvin probe 

force and electrostatic force microscopies. 

F. Bassani 1 , S. Tirano 1 , D. Deleruyelle 1 , Z. Lin 2 , and G. Bremond 2 (1. Institut Matériaux 

Microélectronique Nanosciences de Provence, UMR CNRS 6242, Avenue Escadrille Normandie-Niemen - Case 

142, F-13397 Marseille Cedex 20, France.2. Institut des Nanotechnologies de Lyon, UMR CNRS5270, Université de 

Lyon, Institut National des Sciences Appliquées de Lyon, Bât. Blaise Pascal, 20, avenue Albert Einstein - 69621 

Villeurbanne Cedex, France") franck.bassani@im2np.fr 

Over the past decade, semiconductor nanocrystals (NCs) have attracted much attention due to their unique 

physical properties and potential use for a wide range of optoelectronic and electronic devices. Among the 

latter, NCs based memories exploit the storage of charges in NCs spatially distributed on a thin tunnel oxide 

thus offering many advantages over conventional non-volatile memories. At these small sizes, below 10 nm, 

new physical phenomena can be visible even at room temperature such as Coulomb blockade, single electron 

transfer or quantization charges effect. Accordingly, it is interesting to probe the electrostatic properties at 

the nanometer scale by developing nanocharacterization tools. Scanning probe microscopy techniques such 

as scanning capacitance microscopy, electrostatic force microscopy (EFM) and Kelvin probe force 

microscopy (KPFM) have been recently used to investigate charge distribution in different materials. 

In this work, we investigate injection and retention of charges in Ge NCs formed by a dewetting process on a 

thermally-grown SiO 2 layer by using both KPFM and EFM techniques. Different samples with various Ge 

NCs size and density have been investigated. 

The formation of Ge NCs results from a dewetting process of a thin amorphous Ge layer that occurs during 

annealing at 750°C in ultra-high vacuum growth chamber. In previous work, we found that the average 

roportional to the Ge layer thickness (t) and their density (D) is inversely 

7*t and 

D 6.10 -3 *t -2 . 

Extraction or injection of electrons in these nanostructures was carried out applying a positive or negative 

bias on the conductive tip of the atomic force microscope. The temporal decay and the corresponding lateral 

spreading of injected charges have been quantified by KPFM and EFM which measure, respectively, the 

surface potential and phase shift of the cantilever resonance due to the electrostatic force gradient induced by 

the presence of these spatially localized charges. A quantitative determination of the injected charges can be 

made using a simple model of plane-plane capacitors for a given tip-surface interaction, linked to the height 

of registration used in the lift mode. The results show a strong confinement of charges in Ge NCs altogether 

with long retention times which are promising for their integration in future generations of non-volatile 

memories. 

39


10H10-10H30 

Chemically Grown La0.7Sr0.3MnO3/Single Crystal Heteroepitaxies. 

1J.Zabaleta, 1P.Abellán, 2M.Jaafar, 1M.Paradinas, 3A.J.Katan,1C.Montón, 

1A.Crespi, 1R.Vlad, 2A.Asenjo, 4M.J.Casanove, 1C.Ocal, 3M.B.Salmeron, 

1F.Sandiumenge, 1N.Mestres, 1T.Puig, 1X.Obradors (1 Institut de Ciència de Materials de 

Barcelona, ICMAB-CSIC, Barcelona, Spain; 2 Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, Madrid, 

Spain; 3 Lawrence Berkeley National Laboratory, Berkeley, California,USA 4CEMES-CNRS, Toulouse, France) 

Llorens jzabaleta@icmab.es 


The development of self-assembly processes to pattern large areas with epitaxial ferromagnetic manganite 

nanostructures will provide a model system to establish the influence of the ferromagnetic behaviour at the 

nanoscale. This requires a good understanding of the formation mechanisms of these nanostructures (strain 

relaxation and surface energies) as well as a good control of growth parameters. 


In this work we study self-assembled La0.7Sr0.3MnO3 (LSMO) nanoislands (lateral size


of nanoscience including tunnel junctions, nano-powders, nano-wires, clustering effects in heavily-doped 

ultra-shallow junctions and reactive diffusion in ultrathin films used for contacts in microelectronics [7,8,9]. 

Unique capabilities of atom probe tomography in nanoscience in particular in nano-electronics will be 

highlighted on the basis of some selected illustrations. 

[1] A. Cerezo, I. J. Godfrey and G. D. W Smith, 1988, Rev. Sci. Instr. 59 (6), 862 

[2] D. Blavette, A. Bostel, J.M. Sarrau, B. Deconihout and A. Menand, 1993, Nature 363, 432 

[3] D. Blavette, E. Cadel, A. Fraczkiewicz, A. Menand, 1999, Science 17, 2317 

[4] D. Blavette, T. Al Kassab, E. Cadel, A. Mackel, M. Gilbert, O. Cojocaru, B. Deconihout, 2008, Intern. Journ. of. Mater. Res. 99 (5), 454 

[5] B. Gault, F. Vurpillot, A. Vella, M. Gilbert, A. Menand, D. Blavette, B., 2006, Rev. Sci. Instr. 77, 043705 

[6] T. F. Kelly and M. K. Miller, 2007, Rev. Sci. Instrum. 78, 031101 

[7] D.E. Perea, J.E. Allen, S.J. May, B.W. Wessels, D.N. Seidman, L.J. Lauthon, 2006, Nano lett. 6 (2) 181-185 

[8] O. Cojocaru-Mirédin, D. Mangelinck, K. Hoummada, E. Cadel, D. Blavette, Scripta Mater. Volume 57, Issue 5 (2007) 373-376 

[9] O. Cojocaru-Mirédin, D. Mangelinck, D. Blavette, Journ. of Applied Physics (2009) to appear 

17H00-17H20 

Advanced SEM and TEM investigations of individual and self-assembled 

colloidal PbSe nanocrystals. 

M. CHEYNET 1 , T. NEISIUS 2 , S. LAZAR 3 , E. RAUCH 1 , O. ROBBE 4 , J. 

HABINSHUTI (1SIMAP-PHEMA - CNRS Université Grenoble – France 2IM2NP - CNRS Université 

Marseille Saint Jérôme - France 3FEI company Eidendhoven – Neederland 4LASIR Université Scientifique et 

Technologique de Lille – France). 

1- Introduction 

In contrast to II-VI (CdSe) and III-V (InP), IV-VI lead chalcogénide semiconductor compounds (PbSe, PbS 

and PbTe) present perfect symmetric charge-transfer wave functions (a + = e - ), very large exciton radii (PbSe: 

46 nm), highly symmetric crystal structures (PbSe: rock salt structure), very small “bulk” band gap energies 

(PbSe: 0.26 eV) and relatively low surface effects (for PbSe with R/a B = 0.1, only 45 at% are at the surface). 

All these properties contribute to a high potential of quantum confinement for IV-VI compounds and open 

new fields of applications for them in the domains of optoelectronics and biophysics [1-5]. However, such 

exciting properties are strongly related to nanocrystals shape, size, size distribution, chemistry, crystal 

structure and to the NCs capacity to self-assemble in superlattices. Hence, each new synthesis scheme 

requires to carefully controll these parameters, at both individual nanocrystal scale and self-assembled 

arrays. Several techniques are today well-adapted to control parameters such as shape, size distribution, 

chemistry, crystal structure and can sometimes give in the same time information about electronic properties 

at the individual nanocrystal (2 to 6 nm) or for self-assembled structures scale, i.e. scanning tunneling 

microscopy (STM), grazing incidence small angle X-ray scattering (GISAXS), atomic force microscopy 

(AFM), transmission electron microscopy (TEM). However, among these techniques, the only one able to 

determine all these parameters in the same experimental environment from the nanometer to several hundred 

of nanometer scale is electron microscopy. In this work, colloidal PbSe NCs were investigated using a FEI 

TITAN 80-300 equipped with a monochromator as well as a probe and/or image Cs correctors, and a ZEISS 

Ultra 55 equiped with a STEM detector. From HREM images series, particle size distribution, shape, crystal 

structure of NCs as well as crystal structure relations and spacing between NCs have been determined from 

three nanoparticles classes i.e. around 7 nm, 6 nm and 4.7 nm average size as indicated by near infra-red 

absorption measurements. Crystal orientation relations were obtained using ASTAR software [6] 

(www.nanomegas.com) and NCs spacing using the Aphelion (www.adcis.ne) image analysis software. From 

the analysis of the low energy loss spectra recorded from individual and self-assembled NCs, electronic 

properties i.e. band gap and low energy transistions were extracted using the procedure in reference [7]. 

41


Results were then discussed on the basis of theoretical calculations [8] and density of states function 

measurement using resonant shell-tunneling Spectroscopy experiments [9]. Only the results related to the 7 

nm are reported here. 

2 - Results 

2-1 Geometry, size and spacing distribution, crystal structure and relative orientation. 

A typical Scanning Transmission Electron Microscope (STEM-FEG-SEM) is displayed in Figure 1. This 

images show that the PbSe nanocrystals have a well-controlled size and shape and can locally form ordered 

close-packed arrays as indicated from calculated Fast Fourier Transformations (FFT) presented face to face. 

In the scheme of one NCs layer, hexagonal arrangement is close to be perfect while for NCs bilayers, the 

defects introduce by size distribution effect, rapidly break the simple hexagonal arrangement existing locally, 

to generate new geometrical stackings i.e. grids, roses. STEM-SEM images are too noisy if observed at the 

magnification necessary to make accurate measurements of the nanocrystals size. In contrast, TEM images 

recorded in High Resolution mode using the Cs objective corrector makes it possible, even at rather low 

magnifications. In this mode, one can observe several dozen of PbSe NCs which show lattice fringes and 

well-defined outlines. It is thus possible to make a rather rapid determination of the shape, mean size, size 

and spacing distribution. Typical histograms of the variation of NCs size and spacing between NCs displayed 

figure 2, show that NCs size distribution is very narrow. More than 85% of the nanocrystals have diameters 

ranging between 6.9 and 7.1 nm, with a mean size of 7.05 nm. In contrast, NCs spacings distribution is larger 

and spreads from 1 to 4 nm with less than 50% equal to 2 nm. HREM images in figure 3, show that most of 

the nanoparticles appear roughly spherical, but some of them i.e. thoses with the largest size, show facets. 

Therefore, due to projection effects, even spherical nanocrystals can have more or less facetted shapes. Since 

some NCs are naturally in [111] or [110] zone axis, the electron diffraction patterns calculated using FFT, 

allow to determine that PbSe NCs are face centered cubic (FCC) with a Fm3m space group. Using the 

ASTAR software, it is possible to make mapping of the crystal structure orientation in the transmission 

mode, similarly to electron backscattering mapping in the scanning mode. Figure 4 shows the result obtained 

for an HRTEM image of 39.2 nm 2 scanned with a window of 5.7 nm 2 . As indicated by the colour code used 

to identify the orientation within the standard triangle, preferential orientations are clearly revealed. It may 

be deduced that the z axis is not random but that the particles are free to rotate around. This result is in 

agreement with the observations we did locally, which have shown that in close-packed arrays, nanocrystals 

tend to form chains along the direction. Such a favoured arrangement had already been predicted and 

theoretically explained on the basis of dipole moment values reported by Cho et al.[4] but had never clearly 

observed. 

2-2 Electronic properties of single and self-assembled nanocrystals. shows the single scattering distribution 

spectra (SSDS) calculated from experimental low-energy loss spectra recorded from a single 7 nm PbSe 

nanocrystal and a 2D self-assembled structure composed of about fifty PbSe nanocrystals with 7 nm mean 

size, deposited on a 30 nm thick Si 3 N 4 film. This spectrum shows numerous features resolved in the very low 

energy region (0 - 4 eV), each one corresponding to a more or less sharp intensity jump. As expected, spectra 

recorded under similar conditions on the Si 3 N 4 film show the absence of structure in the energy range below 

4.5 0.1 eV. Only a very weak and uniform background, due to the Bremstralung induces by the NCs 

support is observed. Thus, the first sharp intensity jump in the NCs or self-assembled structure spectra 

corresponds to E g i.e. the PbSe NCs band gap energy. For both, individual and simple hexagonal selfassembled 

NCs an energy equal to 0.67 eV is measured. This value is consistent to those obtained from 

absorption measurements performed in parallel on the same slef-assembled samples. These data also well 

agree the theoretical values calculated by different authors [5-8-10]. 

42


3 – Conclusion : 

The relevance of SEM and TEM in state of art of these instruments i.e. field emmision gun, and scanning 

transmission electron detector for SEM, Cs correctors (probe-ojective) and monochromator for TEM, is 

clearly demonstrated. In the context of colloidal PbSe NCs and associated superlattices, we have shown that 

the quantum confinement due to the nanometer size effects of colloidal PbSe nanoparticles involve the band 

band opening from 0.27 to 0.67 eV and that these properties are well transfered to self-assembled structures. 

In the scheme of self-assembled structures containing a lot of defects, the band gap shuts again and becomes 

lower than the experimental resolution achieved using EELS. 

Bibliography 

[1] Y. Yadong and A. P. Alivisatos Nature 437, 2005, 664. 

[2] M. Klokkenburg et al. Nano Letters 7, 9, 2007, 2931. 

[3] H. Hui et al. Nano Letters 2, 11, 2002, 1321. 

[4] K. Cho et al. J. Am. Chem. Soc. 127, 2005, 7140 

[5] G. Allan et al. Phys. Rev. B 70, 2004, 245321. 

[6] E. Rauch et al., Arch. Metall. Mater. 50, 2005, 87. 

[7] R. Erni et al. Ultramicroscopy 107, 2007, 267. 

[8] R. Koole et al. Small 4, 2008, 127. 

[9] P. Liljeroth et al. PRL 95, 2005, 086801. 

[10] B. Grandidier IEMN Lille , private communication 2009. 

17H20-17H40 

Overgrowth of Ge on Mn5Ge3/Ge heterostructures. 

M.-T. Dau1, T. LeGiang1, A. Spiesser1, L.A. Michez1, M. Petit1, J.-M. Raimundo1, 

R. Daineche2, L. Favre2, I. Berbezier2, V. Le Thanh1 (1 Centre Interdisciplinaire de 

Nanoscience de Marseille (CINaM-CNRS), Aix-Marseille Université, Campus de Luminy, case 913, 13288 

Marseille cedex 09, France; 2 IM2NP-CNRS, Aix-Marseille Université, case 142, 13397 Marseille cedex 20, 

France) 


In recent years, the development of spintronic materials which are compatible with of group-IV 

semiconductors has received growing interest. Work in this direction is motivated by the hope that it can 

offer possibility to overcome the ultimate scaling limits of Si-based CMOS technology, which are about 22 

nm, by adding novel functions, the spin angular momentum. Diluted magnetic semiconductors (DMS) are 

particularly interesting materials since they can easily be integrated into semiconductor heterostructures and 

spin injection from a DMS is expected to be very efficient because of the natural impedance match to 

semiconductors [1]. However, the application of DMS is still hampered by its low ferromagnetic ordering 

temperature. In most DMS investigated up to now, the ferromagnetic order subsists, in the best case, up to a 

temperature of ~170K [2]. 

Recently, an alternative approach has been proposed, which consists of synthesizing high Curie temperature 

compounds that can be epitaxially grown on Si or Ge and act as a spin injector [3]. Among these compounds, 

Mn5Ge3 is of particular interest since it is the most stable phase observed in the form of thin films in the 

Ge:Mn phase diagram [4]. For spintronic research and applications, such as spin valves or giant magnetoresistance 

(GMR) multilayer structures, it is desirable to achieve epitaxial growth of Ge on top of Mn5Ge3 

films with controlled interfaces and crystalline quality. The aim of the present work is to study the Mn 

segregation and intermixing process during subsequent growth of Ge on Mn5Ge3/Ge(111) heterostructures. 

43



To study the Ge overgrowth on Mn5Ge3, we first grow a 25 nm thick Mn5Ge3 layer on Ge(111) substrates 

by depositing Mn at room temperature followed by a thermal annealing at ~450 °C. The surface 

reconstruction prior to Ge deposition is a (√3x√3)R30, characteristic of Mn5Ge3. During Ge deposition, we 

have found via RHEED that the (√3x√3)R30 reconstruction persists up to a thickness of 10 nm for a Ge 

growth temperature of 250 °C and can be larger than 200 nm for a growth carried out at 450 °C. This 

indicates that Mn has segregated on the Ge growing surface and the segregation length depends on the 

growth temperature. Figures 1 and 2 represent two typical TEM images obtained after depositionof 60 nm of 

Ge on a 25 nm thick Mn5Ge3 layer at 250 and 450 °C, respectively. These images reveal that the Ge 

deposition has greatly modified the underneath Mn5Ge3 layer. For a Ge deposition carried out at 250 °C, the 

underneath Mn5Ge3 layer is still present but some defects inside the layer have appeared and the interfaces 

of Mn5Ge3 with both Ge substrate and Ge overgrowth become rough. For Ge growth at 450 °C, the initial 

Mn5Ge3 layer has been destroyed, a part of Mn diffuses into the Ge substrate forming Mn5Ge3 clusters, the 

other part segregates on top of the growing surface, reacts with deposited Ge to form a Mn5Ge3 layer. As a 

consequent, the thickness of the remaining Mn5Ge3 layer on the top surface is about 17 nm, compared to the 

initial thickness of 25 nm. 


The Mn segregation pathways and reaction with deposited Ge at various substrate temperatures have been 

experimentally evidenced. We have combined numerous techniques, structural characterizations via 

RHEED, TEM, SIMS along with magnetic characterizations by means of VSM, to investigate this 

phenomenon. The mechanisms of Mn segregation will be discussed by considering the surface energy and 

the solubility of Mn in Ge. 

Fig. 1: TEM image of a sample obtained after deposition of 60 nm of Ge on a 25 nm thick Mn5Ge3 layer at 250 °C. 

44


Fig. 2: TEM image of a sample obtained after deposition of 60 nm of Ge on a 25 nm thick Mn5Ge3 layer at 450 °C. A part of Mn has diffused into 

the substrate and the surface Mn5Ge3 layer has a thickness of ~17 nm. 

References 

[1] O.M.J. van ‟t Erve, G. Kioseoglou, A. T. Hanbicki, C. H. Li, B.T. Jonker, R. Mallory, M. Yasar, A. Petrou, Appl. Phys. Lett 84 (2004) 4334. 

[2] Y.D. Park, A.T. Hanbicki, S.C. Erwin, C.S. Hellberg, J.M. Sullivan, J.E. Mattson, T.F. Ambrose, A. Wilson, G. Spanos, B.T. Jonker, Science 295 

(2002) 651. 

[3] Y. Ando, K. Hamaya, K. Kasahara, Y. Kishi, K. Ueda, K. Sawano, T. Sadoh, and M. Miyao, Appl. Phys. Lett. 94 (2009) 182105; R. Jaafar, Y. 

Nehme, D. Berling, J. L. Bubendorff, A. Mehdaoui, C. Pirri, G. Garreau, and C. Uhlaq-Bouillet, Appl. Phys. Lett. 93 (2008) 033114; C. Zeng, S.C. 

Erwin, L.C. Feldman, A.P. Li, R. Jin, Y. Song, J.R. Thompson, H.H. Weitering, Appl. Phys. Lett. 83, 5002 (2003). 

[4] S. Olive-mendez, A. Spiesser, L.A. Michez, V. Le Thanh, A. Glachant, J. Derrien, T. Devillers, A. Barski, M. Jamet, Thin Solid Films 517 (2008) 

191. 

[5] A. Spiesser S.F. Olive-Mendez, M.-T. Dau, L.A. Michez, A. Watanabe, V. Le Thanh, A. Glachant, J. Derrien, A. Barski, M. Jamet, Thin Solid 

Films 518 (2010) S113. 

17H40-18H00 

Assessing mechanical strain at the nanometer scale induced in silicon channel 

by periodic gate lines arrays through high resolution X-ray diffraction and 

modeling 

S. Escoubas1,2, G. Gaudeau1,2, Y. Ezzaidi1,2, O. Thomas1,2, P. Morin3 (1 Aix- 

Marseille Université, IM2NP; 2 CNRS, IM2NP UMR 6242, Faculté des Sciences et Techniques, Campus de Saint- 

Jérôme, Avenue Escadrille Normandie Niemen, Case 142, 13397 Marseille Cedex, France; 3 ST Microelectronics, 

850 rue Jean Monnet, 38920 Crolles, France) stephanie.escoubas@im2np.fr 


Periodic structures are often encountered in semiconductor devices whether they are prepared by lithography 

or by self-organization. The lateral dimension of the devices is continuously decreasing with increasing 

performances. Stress engineering is becoming of increasing interest to enhance microelectronics device 

performance in particular by improving electron or hole mobility [1]. For that purpose, one way consists in 

stressing the transistor Si channel by depositing a strained layer on top of the polysilicon gate. Silicon nitride 

is a good candidate as the layer can be either tensile or compressive depending on the process parameters [2]. 

Even though the strain field induced in silicon can be predicted with the help of finite elements modelling, 

corroborating the calculated strain field with measurements is crucial. As a consequence, measuring strains 

or stresses at the nanometer scale is a real challenge. 

45


In this study we investigate the periodic strain field in silicon with high resolution X-ray diffraction, which is 

very sensitive to local strains (


18H00-18H20 

Airbrush-spray deposition of colloidal polymer film investigated by GISAXS. 

A. Buffet1*, G. Herzog1, M. Schwartzkopf1, M.M. Abul Kashem1, J. Perlich1, V. 

Koerstgens2, P. Müller-Buschbaum2, R. Gehrke1, S.V. Roth1 (1HASYLAB-DESY, 

Notkestr. 85, D-22607 Hamburg, Germany; 2TU-Muenchen, Physik-Department Lehrstuhl E13, Garching, 

Germany) *adeline.buffet@desy.de 


Nowadays, nanoparticle thin films are used in a large range of advanced technologies such as sensor coating 

[1], solar cell [2] or magnetic recording [3] technology. In the last few years, organic-based hybrid devices 

received strong attention from both academy [4] and industry because of their potential for low-cost 

production and flexible device applications [5]. 


Recently, the novel technique of airbrush-spray deposition was used in the fabrication of organic-based 

multilayer devices such as solar cells [6]. This technique allows for performing rapid deposition of organicbased 

nanostructured layers showing high homogeneity over a large area and is thus of great interest in 

industrial applications. 

We used Grazing Incidence Small Angle X-ray Scattering (GISAXS) and Atomic Force Microscopy to 

investigate the structure of colloidal nanoparticle films deposited on flat Si-substrates by using a commercial 

airbrush-spray system. We investigated the film nanostructure formation as a function of deposited colloidal 

particles, solvent and sample-to-spray nozzle distance. 


Our study shows a strong dependence of the film homogeneity on the substrate-to-spray nozzle distance and 

the strong influence of the solvent choice on the film lateral ordering. We show that line-type structures can 

be installed. This novel deposition technique opens a promising route to generate laterally structured 

templates and scaffolds for the fabrication of ultrahigh-density media 

[1] H. Walter, et al., Optical Engineering 45, 103801 (2006) 

[2] J. Perlich et al., Chem. Phys. Chem. 10, 799 (2009) 

[3] S. Park et al., Science 323, 1030 (2009) 

[4] S.V. Roth, et al., Langmuir, DOI: 10.1021/la9037414 (2009) 

[5] G. Kaune et al., Appl. Mater. & Interf, DOI: 10.1021/am900592u (2009) 

[6] R. Green, et al., Appl. Phys. Lett. 92, 03330 (2008) 

47


Room Port-Pin 

8H30-9h10 

Electrical, optical and structural properties of self-organized Ge nanocrystals. 

N.L. Rowell1, D.J. Lockwood1, I. Berbezier2, G. Amiard2, L. Favre1, M. 

Aouassa2,4, A. Ronda2, K. Gacem3, A. El Hdyi3, M. Troyon3, M. Scarselli4, P. 

Castrucci4, M. De Crescenzi4, H. Maaref5 (1 National Research Council of Canada, 1200 Montreal 

Road, Ottawa, ON K1A 0R6, Canada; 2IM2NP, CNRS – Univ. Aix Marseille, Campus St. Jérôme, Case 142, 13397 

Marseille CEDEX 20, France ; 3LMEN, Case 15, UFR Sciences, Université de Reims, Champagne-Ardenne, 51687 

Reims Cedex 2, France ; 4 Univ. Di Roma 2 Tor Vergata, Via della Ricerca Scientifica , Roma, Italy Uni Tor 

Vergata; 5 LPSCE, Faculté des Sciences de Monastir, Uni. Monastir, Avenue de l'environnement 5019 Monastir, 

Tunisia) Nelson.Rowell@nrc-cnrc.gc.ca 


During the last decade, significant progress has been made towards the development of new processes for 

integrating nanostructured materials into novel micro- and opto-electronic devices. The nanostructures of 

interest include arrays of clusters, nanoparticles, quantum dots and wires. For most of the potential 

applications the nanostructures must be ordered and highly homogeneous in size in order to exploit the 

quantum effects for device applications. Recently notable advances have been made in dot self-assembly and 

in our understanding of their physical properties [1]. 


Achieving high densities of self-organized Ge quantum dots directly on Si surfaces remains problematic. 

The normal growth mechanism - Ge clustering from a Ge wetting layer - places constraints on the dot size, 

density, and distribution limiting the best-case dot density to between 109 and 1010 cm−2. At the same time, 

the quality of the dots is compromised by interdiffusion that leads to GeSi alloying at dot interfaces. 

However for SiO2 substrates, Ge islanding, since it is driven by a dewetting process (surface diffusion and 

equilibrium surface morphology), occurs without forming a wetting layer. Therefore a much larger dot 

density [2] is possible and dot patterning can be achieved [3-5] with such a substrate. For example, in [5], 

crystalline Ge dots with an average size of 5 nm and a density of 3×1012 cm−2 were obtained that displayed 

the onset of (001) and (113) faceting and a low aspect ratio. Such morphology is attributed to the 

thermodynamically limited, equilibrium shape of Ge in this system. 

We will discuss the influence of size on the structural, electrical and optical properties of Ge dots. We 

demonstrate using transmission electron microscopy that Ge dots exhibit a pseudo-equilibrium shape 

independent of annealing conditions. The bandgap of individual dots determined by scanning tunnelling 

spectroscopy is directly related to their size as predicted by quantum confinement [2,6]. This is confirmed by 

optical characterization of Ge dots embedded in an amorphous Si matrix [7,8]. In addition, C-V and I-V 

characteristics were attributed to electron (hole) injection/emission in the Ge dots, which display good 

memory effects with long storage times [9,10]. 


Using a combination of structural, optical and electronic characterization techniques, we have demonstrated 

novel properties that can be attributed to quantum confinement effects resulting from the ultra-small size of 

Ge dots. 

[1] I. Berbezier, A. Ronda, Surf. Sci. Rep. 64, 47 (2009). 

[2] I. Berbezier, A. Karmous, A. Ronda, A. Sgarlata, A. Balzarotti, P. Castrucci, M. Scarselli, M. De Crescenzi, Appl. Phys. Lett. 89, 063122 (2006). 

48


[3] A. Pascale, I. Berbezier, A. Ronda, P. Kelires, Phys. Rev. B 77, 075311 (2008). 

[4] I. Berbezier, A. Ronda, Phys. Rev. B 75, 195407 (2007). 

[5] A. Karmous, I. Berbezier, A. Ronda, Phys. Rev. B 73, 075323 (2006). 

[6] M. Scarselli, S. Masala, P. Castrucci, M. De Crescenzi, E. Gatto, M. Venanzi, A. Karmous, P.-D. Szkutnik, A. Ronda, I. Berbezier, Appl. Phys. 

Lett. 91, 141117 (2007). 

[7] N.L. Rowell, D.J. Lockwood, A. Karmous, P. D. Szkutnik, J.-P. Ayoub, I. Berbezier, A. Ronda, Superlattices and Microstructures 44, 305 (2008). 

[8] N.L. Rowell, D.J. Lockwood, I. Berbezier, A. Ronda, J. Electrochem. Soc. 156, H913 (2009). 

[9] A. El Hdiy, K. Gacem, M. Troyon, A. Ronda, F. Bassani, I. Berbezier, J. Appl. Phys. 104, 063716 (2008). 

[10] K. Gacem, A. El Hdiy, M. Troyon, I. Berbezier, A. Ronda, Nanotechnology 21, 065706 (2010). 

9H10-9H30 Epitaxial SiGe self-assembled island growth by Surface Thermal Diffusion : 

shape transition, intermixing and strain relaxation. 


G.M. Vanacore1, M.Zani1, G. Isella2, J. Osmond2, E. Bonera3, F. Montalenti3, A. 

Picco3, and A. Tagliaferri1 (1Dipartimento di Fisica, Politecnico di Milano, P.zza Leonardo da Vinci, 32- 

20133 Milan, Italy 2L-NESS, Dipartimento di Fisica del Politecnico di Milano, Via Anzani 52, I-22100, Como, Italy 

3Dipartimento di Scienza dei Materiali, and L-NESS, Università di Milano-Bicocca, via Cozzi 53, I-20125 Milano, 

Italy) 

Growth of Ge on Si surfaces has attracted much attention because of its importance both for the 

semiconductor technology and for the comprehension of fundamental physical processes. The formation of 

self-assembled SiGe islands is strongly dependent on the surface diffusion coefficient of Ge and Si atoms, 

which rapidly vary with the temperature [1,2]. In this work, we present an experimental study by atomic 

force microscopy, scanning Auger microscopy and micro-Raman spectroscopy of thermodynamically stable 

SiGe islands epitaxially grown by surface thermal diffusion from a pure Ge stripe deposed on the Si(100) 

surface. 


Self-assembled islands with different faceting and dimensions varying over an order of magnitude are 

produced by surface thermal diffusion of Ge at 600, 650 °C and 700 °C. They originate by the nucleation of 

Ge atoms moving from artificially made nano-sized stripes used as sources of diffusion directly placed on 

the sample surface. The total surface coverage of Ge strongly depends on the distance from the source stripe, 

so that the method allows to investigate the island growth over a wide range of dynamical regimes. It is 

shown that the region with highest Ge coverage (close to the stripe) presents the highest SiGe island density 

and the lowest average island sizes, while where the coverage decrease to about 4 ML (farter away from the 

stripe) the lowest density and the biggest average dimensions of the islands are attained, with a 

correspondent shape evolution between smaller and larger islands. The statistics of the island population are 

discussed within a semi-quantitative model of diffusion and nucleation. The model is based on few key 

assumptions, in agreement with experimental [3-6] and theoretical [7] studies: an approximate exponential 

form for the change in the chemical potential with the wetting layer thickness [8], a capture-zone growth 

behaviour [9] and the competition between Ge and Si diffusion dynamics in determining the final Si content 

of each island. Our results give experimental evidence that the island nucleation by surface thermal diffusion 

evolves at microscopic level following a diffusion-limited growth mechanism, resulting in islands in their 

thermodynamic equilibrium state. The role of Si incorporation and the plastic relaxation of single islands at 

growth temperatures higher than 600 °C are experimentally investigated and critically discussed. 

49



The nucleation process of SiGe self-assembled islands epitaxially grown on Si substrate by Surface Thermal 

Diffusion has been experimentally studied. The method allowed to investigate the growth process over a 

wide range of Ge coverages at the same time. From the evolution of size and density exhibited by the 

nucleated islands as a function of the Ge coverage, we propose a model where the surface diffusion on the 

long scale is kinematically limited, while the SiGe islands grow reaching a quasi-equilibrium state depending 

on the local final conditions. 

4 – Bibliography 

[1] J. Drucker and S. Chaparro, App. Phys. Lett. 71 614 (1997). 

[2] T.I. Kamins and R.S. Williams, App. Phys. Lett. 71 1201 (1997). 

[3] G. Medeiros-Ribeiro et al., Science 279, 353 (1998). 

[4] H. J. Kim et al., J. Appl. Phys. 95, 6065 (2004). 

[5] A. Rastelli et al., Nano Lett. 8, 1404 (2008). 

[6] T.U.Schülli et al.,APL 89, 143114 (2006); M. Brehm et al., Appl. Phys. Lett. 93, 121901 (2008) 

[7] Y. Tu and J. Tersoff, Phys. Rev. Lett. 98, 096103 (2007). 

[8] I. Daruka and A.-L. Barabàsi, Appl. Phys. Lett. 72, 2102 (1998). 

[9] P.A. Mulheran and J.A. Blackman, Phys. Rev. B 53, 10261 (1996). 

9H30-9H50 

Exploiting the interface between randomly nucleated and ordered dots for 

unrolling SiGe/Si dot properties on a micrometer scale. 

M. Grydlik, M. Brehm, F. Hackl, F. Schäffler, T. Fromherz, and G. Bauer (Institute of 

Semiconductor and Solid State Physics, Johannes Kepler University, Linz) martyna.grydlik@jku.at 


Ordering of quantum dots in pre-defined positions is supposed to fulfill necessity of their addressability. In 

the last years this ordering became feasible in several semiconductor hetero-systems like InAs on GaAs(001) 

and SiGe on Si(001). For the understanding of basic growth phenomena of such dots and, even more 

important, for many applications, fields with small pit-periods (40 nm – 300 nm) are produced, e.g. by means 

of electron beam, focused ion beam or interference lithography, offering only limited test areas of pitpatterned 

substrate. 


In this work we demonstrate for the representative SiGe hetero-system that the border of such fields can 

influence the quantum dots growth inside the pit-patterned field over a lateral distance up to 50 µm inside the 

field. The pits act as favorite nucleation sites for islanding and therefore act as material sink for the Ge that is 

deposited outside of the field. This strong lateral surface diffusion effect can be exploited in order to unroll 

the evolution of quantum dots growth on pit-patterned substrates within these 50 µm. The middle of the field 

represents the Ge lean environment while the border represents a situation where a larger amount of Ge is 

available per pit, i.e., the dots at the border become larger than the ones in the middle. 

We studied the evolution of dot-shapes and Ge concentrations via atomic force microscopy (AFM) and µ- 

photoluminescence (PL) measurements. From the shift of the PL originating from dots with different shape, 

Ge concentrations of the dots can be extracted. From AFM measurements of the dot volumes we evaluated 

material capture rates for different dot types. 

50



For potential devices it is important that island properties do not vary at all across the fields. In this work we 

will show how by carefully adjusting the growth parameters on fields as small as 200x200 µm2 it is feasible 

to obtain a highly uniform quantum dot size distribution across the entire field, including the border regions. 

9H50-10H10 

Characteristic interaction distance between Si nanodots and Er3+ ions in welldefined 

multilayer films. 

Ying-Wei Lu1, M. Christian Petersen1, J. Lundsgaard Hansen,1 A. Nylandsted 

Larsen1, R. V. Skougaard Jensen2, T. Garm Pedersen2, K. Pedersen2 (1. Department of 

Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark; 2. Department of Physics and 

Nanotechnology, Aalborg University, DK-9220 Aalborg Ø, Denmark) ylu@phys.au.dk, mcp@phys.au.dk, 

johnlh@phys.au.dk, anl@phys.au.dk rj@nano.aau.dk, tgp@nano.aau.dk, kp@nano.aau.dk 


Er3+ photoluminescence (PL) sensitized by amorphous or crystalline Si nanodots has attracted intensive 

attention since Si nanodots can enhance Er3+ emission due to interaction between carriers in Si nanodots and 

Er3+ ions. However, the nature of the sensitizing role played by the Si nanodots is still being debated. 

Several groups have studied the characteristic interaction distance between Si nanodots and Er3+ ions. In 

these studies, however, the films were annealed at high temperatures which might result in Er diffusion, and 

accordingly, induce a distribution in interaction distance due to ill-defined microstructures. Therefore, low 

temperature annealed films with well-defined microstructure are better candidates for the characterization of 

the interaction distance since Er diffusion can be completely avoided. 


10 layers each consisting of a-Si/SiO2:Er/SiO2 sublayers were deposited on p-type, (001) Si wafers by rfmagnetron 

sputtering without substrate heating. The thickness of the a-Si sublayers were fixed at about 3 nm. 

The thickness of the SiO2:Er and pure SiO2 sublayers were varied such that the SiO2:Er sublayer thickness 

increased from 0 to 5 nm, while the pure SiO2 sublayer thickness decreased accordingly to keep the 

thickness of the total SiO2 layer fixed at 15 nm. After deposition, all films were annealed at 500 °C for 1 h in 

95% N2 + 5% H2 and at 1100 °C for 1 h in pure N2, respectively. Secondary Ion Mass Spectrometry (SIMS) 

profiles indicate that Er diffusion takes place in the films annealed at high temperature but not in those 

annealed at low temperature. Moreover, PL measurements show that different characteristicinteraction 

distances are extracted from the films annealed at different temperatures. Transmission electron microscopy 

(TEM) and time-resolved PL spectroscopy have been employed to characterize the relationship between the 

well- and ill-defined microstructures, and the different interaction models. 


The present investigation demonstrates that the characteristic interaction distance between Si nanodots and 

Er3+ ions strongly depends on the annealing temperature of the films. At high annealing temperature the Er 

starts to diffuse within the SiO2 layer making it impossible to operate with one interaction distance. 

51


10H10-10H30 

Self assembled Ge nanostructures grown on FIB nanopatterned Si substrates. 

I.C. Marcus1,2, I. Berbezier2, A. Ronda2, M.I. Alonso1, M. Garriga1, A.R. Goñi1, 

E.Gomes2, L. Favre2, A. Delobbe3, P. Sudraud3 (1 Institut de Ciencia de Materials de Barcelona 

CSIC, Esfera UAB, 08193 Bellaterra, Spain 2 IM2NP, CNRS – Univ. Aix Marseille, Campus St. Jérôme, Case 142, 

13397 Marseille CEDEX 20,France 3 Orsay Physics, 95 Avenue des Monts Auréliens - ZA Saint-Charles - 13710 

Fuveau, France) 


Semiconductor nanowires (NWs) and nanodots are attractive because of their novel electronic properties and 

possible applications in nanoelectronics, optoelectronics and photovoltaic fields. Several approaches have 

been used to grow the nanowires via vapor-liquid-solid (VLS) and vapor-solid-solid (VSS) mechanisms 

using different metal nanoparticle seeds. Among them gold was found to be the best candidate to control Si 

NWs growth due to the formation of silicide with low eutectic point. Up to date, Ge NWs received much less 

attention than the Si ones. However, compared to silicon, germanium provides better mobility, smaller 

bandgap and a larger exciton Bohr radius, which allows quantum confinement effects at larger nanowire 

sizes. Ge is also used in conventional CMOS technology as a stressor to improve the mobility of transistors. 

Ge or Si/Ge core/shell nanowires represent relevant systems to explore the new physics and applications of 

these nanostructures in various configurations. 


The aim of this work is to control the dimensions, the location and the reproducibility of the nanowire 

formation independently of the chosen growth conditions. In this context, our objective was to develop a 

method to obtain NWs using Au as seed catalysts and to control the size and the density of NWs by varying 

the Au nanocluster features. For this purpose we form two-dimensional arrays of Au nanoclusters using 

mass-filtered focused ion beam (FIB) with Au2+ ions. Two different procedures were followed for the 

formation of the Au nanoclusters. First, we used an ultra-fast grabbing process during ion imaging. Au 

nanoclusters are formed by local mplantation of Au into Si(001) substrate during this grabbing process. The 

FIB experimental parameters adjusted to modify the Au size/density are the scan speed and the pixel 

numbers. In the second approach, an array of nano-holes was milled using FIB Au2+ ions. During hole 

formation Au is locally implanted on the hole walls. The nanopattern size, depth and aspect ratio are changed 

by varying the ion beam current, and dose, dwell time, overlap, and spot size. After the deposition or 

implantation of Au by FIB on the Si surface we form the AuSi clusters by annealing in UHV at 550°C. At 

this temperature the AuSi eutectic phase which is thermodynamically stable forms liquid nanodroplets at the 

Si surface. The 2D-array of AuSi serves in a further step as catalysts seeds for the nucleation / growth of Ge 

nanowires. In the last step, we deposited Ge on the nano-functionalized Si substrate by solid source 

molecular beam epitaxy (MBE). The influence of the growth conditions (annealing time, growth 

temperature, Ge growth rate, growth time) on the morphology of the resulting Ge nanostructures was 

investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). One of the most 

striking results is the formation of Ge nanowires lying on the Si(001) surface with an aspect ratio 

(diameter/length) of about 0.1 and about 1μm in length. We show that the nanowires shape is influenced by 

the dimensions of the pre-existing SiAu droplets. At larger Au content (large holes depth), the Si surface 

becomes too damaged, and the nucleation of ordered nanostructures is annihilated. 


We have developed two different processes based on mass filtered FIB nanopatterning with gold ions that 

allow nice ordering of Ge nanostructures (dots and wires). We show that depending on the nanopatterning 

52


conditions we can form either Ge dots or Ge nanowires. We provide evidence of the preferential nucleation 

of Ge nanostructures (dots and wires) on the pre-existing 2D array of AuSi liquid nanodroplets. The 

influence of the nanopatterns morphology / shape on the nanostructures nucleation and growth is 

demonstrated. The developed process provides a promising way to form large scale 2D-arrays of Ge and 

core-shell SiGe nanowires for various micro-nano-electronic and photovoltaic applications. 

17H00-17H20 

Pit-patterning by UV nanoimprint lithography for the site-controlled selfassembly 

of highly-uniform Si/Ge islands 

FROMHERZ E. Lausecker1, M. Brehm1, M. Grydlik1, I. Bergmair2, M. 

Mühlberger2, T. Fromherz1, G. Bauer1(1 Institute of Semiconductor and Solid State Physics, 

University of Linz, 4040 Linz, Austria 2 Functional Surfaces and Nanostructures, Profactor GmbH, 4407 Steyr, 

Austria) 


In the germanium-on-silicon (Ge-on-Si) system, it has been demonstrated that the nucleation sites of Si/Ge 

islands can be controlled by pre-structuring the Si substrate, allowing the growth of ordered and addressable 

Si/Ge islands. For applications relying on addressability, island-ordering on chip-sized areas and, thus a fast 

and inexpensive patterning method suitable for large areas and sub-100 nm structuring is required. 


Therefore we introduce UV nanoimprint lithography (UV-NIL) for the pit-pattering of molecular-beam 

epitaxy (MBE) substrates. Our quartz nanoimprint molds (1" x 1") contain a pillar pattern that is transferred 

into the Si substrate by UV-NIL and reactive-ion etching. Four pit-patterned fields extend over an area of 3 x 

3 mm 2 . The pits have a depth of 45 nm and a diameter of 200 nm with a period of 400 nm. Six monolayers of 

Ge were deposited at 690 °C by MBE. The island surface is passivated by the growth of a thin Si capping 

layer. Atomic force microscopy images show extremely well-ordered Si/Ge islands. To the best of our 

knowledge, these island arrays represent the largest areas so far reported in literature with coherently ordered 

Si/Ge islands, which are addressable by a second lithographical step. The homogeneous island growth results 

in a significant improvement of the photoluminescence signal. In spatially resolved PL experiments, we 

observe no variation in the PL peak position and linewidth, 


Our results suggest that pit-patterning by UV-NIL opens a route to explore the Si/Ge island formation on 

high-density pattern in the sub-100 nm regime over large areas. Our Si/Ge islands show excellent 

optoelectronic properties and therefore may be integrated as active building blocks in Si based optoelectronic 

devices. 

53


17H20-17H40 

Transport properties of junctions and lattices via solvable models 

GONCHAROV - Nikolai Bagraev, e-mail: impurity.dipole@pop.ioffe.rssi.ru A.F. Ioffe Physico- 

Technical Institute,St. Petersburg. Lev Goncharov, e-mail: : Lev.goncharov@mail.ru Department of Physics of 

St. Petersburg University,198505, St. Petersburg, Russia. Gaven Martin, e-mail : G. J. Martin@massey.ac.nz 

New Zealand Institute of Advanced Study, Massey University Albany campus, Auckland, New Zealand. Boris 

Pavlov,e-mail e-mail: pavlovenator@gmail.com New Zealand Institute of Advanced Study, Massey University 

Albany campus, Auckland, New Zealand, A. Yafyasov, e-mail: yafyasov@bk.ru Department of Physics of St. 

Petersburg University, St. Petersburg, Russia. 

54


17H40-18H00 

Nano-cones Formation on a Surface of Si1-xGex Layers by Laser Radiation. 

A.Medvid‟1,3, P.Onufrijevs1, K.Lyutovich2, M. Oehme2, E. Kasper2 (1Riga Technical 

University, 14 Azenes Str., Riga, LV-1048, Latvia, 2Universitat Stuttgart, Pfaffenwaldring 47, 70569 Stuttgart, 

Germany,3Institute of Semiconductor Physics National Academy of Science of Ukraine, 45 Pr.Nauki, 252650, Kyiv- 

28, Ukraine) medvids@latnet.lv, lyutovich@iht.uni-stuttgart.de 


One of the basic directions in development of modern microelectronics is elaboration of new methods of 

nanosize structure formation and implementation of nanoelectronic components in devices. 


The study of self-assembling nano-cones induced by irradiation of nanosecond Nd:YAG laser pulses on a 

surface of a Si1-xGex solid solution is reported. It is shown that dynamics of nano-cones formation depends 

on concentration of Ge atoms (x) in Si lattice and on the intensity of laser radiation (LR). 

Two different processes of nano-cones formation depending on x are observed. The first one - at higher 

concentration of Ge atoms x = 0.3-0.4 and the second one - at lower concentration of Ge atoms at x=0.15 

take place. 

At the first stage, similar processes of nano-cones formation occur. It means, at low intensity of LR 

I2.0 MW/cm2 nano-cones formation takes place by Stransky- Krastanov mode. On the 

contrary, at lower concentration of Ge atoms cones look like “tree ring” [2] growth due to melting of Ge 

separated islands on the irradiated surface at intensity of LR I=20 MW/cm2. 


Nano-cones formation on the irradiated surface of SiGe strongly depends on concentration of Ge atoms and 

on intensity of laser radiation which can be used for the control of the shape and size of nanostructures. 

4 – References 

1. A. Medvid‟ and L. Fedorenko, Thermogradient mechanism of p-n junction formation by laser radiation in semiconductors. Applied Surface 

Sciences, Vol.197-198, (2002), pp. 877-882. 

2. A. Merdzhanova, M.Rastrelli, S.Stoffel, O.Kiravittaya, G. Schmidt, Island motion triggered by the growth of strain- relaxed SiGe/Si (001) islands. 

Journal of Crystal Growth. Vol.301-302, (2007), pp.319.-323. 

55


18H00-18H20 

High refractive index modification inside Si02 by femtosecond laser created 

self-ordered planar nanostructures. 

David Grojo1,2, Thomas Barillot1, Marina Gertsvorlf1,3, Shuting Lei4, David 

M. Rayner1 and Paul B. Corkum1,3 (1National Research Council of Canada, Steacie Institute for 

Molecular Sciences, Ottawa, Canada 2LP3 –UMR 6182, CNRS-Univ. Méditerranée, Marseille, France 3University 

of Ottawa, Ottawa, Ontario, Canada 4Kansas State University, 2012 Durland Hall, Manhattan, Kansas, USA) 

Illumination with intense femtosecond optical pulses focused to small focal spots modifies dielectrics in such 

a way that the refractive-index can be locally adjusted. This represents today an attractive microfabrication 

method for photonic applications. Here, we investigate the non-uniform nature of the strong laser field 

ionisation in amorphous silica (a-SiO2) which translates in material cracking at a subwavelength scale. 

Under repeated illumination, the cracks migrate to form beautifully-ordered arrays of ~8-nm planar 

nanocracks with a crack-to-crack spacing of λ/2 in the medium. These are extending through the focal region 

with no defect and are oriented perpendicular to the laser polarization [1,2]. The material transport is 

amazingly driven by the strong laser field making possible to change the writing orientation at anytime with 

the polarization. We show the nanotructures are characterized by a very large refractive index change (up to 

Δn/n=1.8%) and form birefringence (ns-np ~0.01 at 800 nm). This offers unprecedented control over the 

linear optical properties of a-SiO2 anywhere in 3-D space. The local change in the focal region leads 

progressively to the self-generation of a polarization dependent biconvex defocusing microlens (Fig). The 

refractive feedback effect on the light that creates the microlens ascribes a self-limited character on the 

writing process that is attractive for technological considerations. This is achieved without any noticeable 

increase in linear losses and opens a route to adding new functionality inside optical fibers or bulk materials. 

[1] V. R. Bhardwaj, E. Simova, P. P. Rajeev, C. Hnatovsky, R. S. Taylor, D. M. Rayner, and P. B. Corkum, Phys. Rev. Lett. 96, (2006)057404 

[2] D. Grojo, M. Gertsvolf, H. Jean-Ruel, S. Lei, L. Ramunno, D. M. Rayner, and P. B. Corkum, Appl. Phys. Lett. 93 (2008) 243118. 

18H20-18H40 

Fabrication of an IR emitting ErQ3-based distributed feedback laser by X-ray 

Interference Lithography. 

S. Prezioso1, P. De Marco1, F. Bisti1, M. Donarelli1, S. Penna2, A. Reale2, S. 

Santucci1, and L.Ottaviano1 (1Dipartimento di Fisica, Università dell‟Aquila, gc-LNGS INFN, Via 

Vetoio, 67100, L‟Aquila, Italy 2Dip. di Ingegneria Elettronica, Univ. degli studi di Roma “Tor Vergata”, Viale 

Politecnico 1, 00133 Roma, Italy) 


Modern telecommunication technology requires to process large volumes of information for scientific, 

military and civil purposes. IR light is the most suitable radiation to sustain petabyte-per-year traffics. IR 

optical fiber technology is sufficiently mature as well as the micro-electronics industry to accept this 

challenge. The bottleneck is represented by the optical interconnection between fiber and chip. The onchip 

collection of the optical information is one of the most promising strategies. 

In this work we propose the fabrication of an IR emitting ErQ3-based distributed feedback laser as the 

onchip light source in charge of transferring the information collected from the chip directly into the optical 

fiber. Using ErQ3 as the active medium, we can combine the perfect adaptability of amorphous organic 

materials to any kind of surface, periodically modulated surfaces included, with the perfect match of Er 

56


emission with the required operating wavelengths (C-band, 1530 - 1560 nm). X-ray Interference Lithography 

(XIL) has been chosen as the preferential technique to produce the gratings that provide the optical feedback. 


In the last years optical gain from organic active media has been observed at different wavelengths lying in 

the near-IR region (up to 1300 nm) [1-3] but still far from the wavelengths required for the optical 

communications. P. Del Carro et al. have recently fabricated a distributed feedback (DFB) laser tunable in 

the range of 890 - 930 nm [4]. Here we present an organic DFB laser exploiting the 4f – 4f transition at 1535 

nm of the Er ion coordinated to the three Quinoline groups of the ErQ3 molecule. A film of amorphous ErQ3 

is deposited by Vacuum Thermal Evaporation on a periodically modulated surface obtained by XIL. 

According to the Bragg condition with the first order of emission (m=1) at 1535 nm, a 472 nm‐pitch has 

been calculated for the DFB cavity and reproduced on the samples with nanometric precision. XIL represents 

the obvious choice to obtain periodic structures, with its capacity to engrave (in few minutes) large areas of 

photoresist (~ 1 mm2) with nanometer (100 nm) size ordered patterns without making use of masks. The XIL 

tool is a low-cost apparatus made of a table-top coherent X-ray source and a simple Lloyd‟s setup where the 

interference patterns are produced by reflection of one half of the laser beam that overlaps with the 

undeflected half in correspondence of the sample surface [5]. The X-ray laser source is a prototype capillary 

discharge plasma source developed at the University of L‟Aquila and emitting 1.5 ns long pulses of coherent 

radiation at λ = 46.9 nm with 0.1 Hz maximum repetition rate, exploiting the single pass amplification of the 

3p-3s transition in Ne-like Ar [6]. 

The effects of the grating surface modulation on the emission properties have been studied as a function of 

the grating period (easily and cheaply tunable with the XIL technique) and of the organic layer thickness. A 

morphological characterization has been performed by Atomic Force Microscopy on both the grating surface 

and the active layer surface. Detailed X-Ray Photo-Emission Spectroscopy measures have been performed to 

complete the characterization of the device. 


The largely diffused use of wide-band optical networks and the increasing request of improving their 

performance are pushing toward the concept of an all-optical information processing. The fabrication of a 

miniaturized organic laser for C-band applications is a step toward an all-optical scenario. The technological 

impact of the novel device will depend on the possibility to adopt the on-chip optical interconnection 

strategy diffusely: the low costs of constituent materials and fabrication techniques are the premise for a vast 

diffusion of the ErQ3-based laser throughout the network. 

[1] M. Casalboni, F. De Matteis, V. Merlo, P. Prosposito, R. Russo and S. Schutzmann, Appl. Phys. Lett. 83, 416 (2003). 

[2] K. Yamashita, T. Kuro, K. Oe and H. Yanagi, Appl. Phys. Lett. 88, 241110 (2006). 

[3] J. Thompson, M. Anni, S. Lattante, D. Pisignano, R. I. R. Blyth, G. Gigli and R. Cingolani, Synth. Met. 143, 305 (2004). 

[4] P. Del Carro, A. Camposeo, R. Stabile, E. Mele, L. Persano, R. Cingolani, and D. Pisignano, Appl. Phys. Lett. 89, 201105 (2006). 

[5] P. Zuppella, D. Luciani, P. Tucceri, P. De Marco, A. Gaudieri, J. Kaiser, L. Ottaviano, S. Santucci and A. Reale, Nanotechnology, 20 (2009), 

115303. 

[6] A. Ritucci, G. Tomassetti, A. Reale, F. Flora and L. Mezi, Phys. Rev. A 70, 023818 (2004). 

57

P R O G R A M WEDNESDAY, JUNE 30 N A N O S E A 2 0 1 0 

Wednesday, June 30 

Session 8 

Room Calendal 

Organic Nanostructures (Chairman: De Crescenzi) 

8H30-9h00 

TEICHERT (a Institute of Physics, University of Leoben, A-8700 Leoben, Austria; b Chair of Atomistic 

Modelling and Design of Materials, University of Leoben, A-8700 Leoben, Austria; c Institute of Solid State 

Physics, Graz University of Technology, A-8010 Graz, Austria) 

Molecular diffusion processes in nanostructured organic thin films 

9H00-9H20 GIOVANELLI (1 IM2NP-CNRS, Aix-Marseille Université, Campus de St. Jérôme, Marseille, France, 2 

Humboldt University, Institut für Physik, Newtonstraße 15, 12489 Berlin, Germany, 3 PIIM-CNRS, Aix-Marseille 

Université, Campus de St. Jérôme, Marseille, France, 4 ELETTRA, Sincrotrone Trieste, Area Science Park, S.S. 14, 

km 163.5, Basovizza (Trieste), Italy) 

Valence band photoelectron spectroscopy of the Zn-Phthalocyanine/Ag(110) 

interface: Charge transfer and scattering of substrate photoelectrons 

9H20-9H40 PERTRAM (Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr.12, D-53115 

Bonn, Germany, *CINAM – CNRS – UPR 3118, Aix-Marseille Université, Campus de Luminy – Case 913, F- 

13288 Marseille, France) 

Phthalocyanine induced nanostructuring of the Au(110) surface 

9H40-10H00 

SCHNEIDER (Institute of Physical and Theoretical Chemistry, University of Bonn - Wegelerstr. 12 D-53115, 

Bonn, Germany) 

Self-organized Porphyrin monolayers on halide-modified noble metal surfaces 

10H00-10H20 

MAS-TORRENT (Institut de Ciència de Materials de Barcelona (CSIC), Campus de la UAB E-0183, 

Bellaterra, Spain; Katholieke UniVersiteit LeuVen, Celestijnenlaan 200-F, 3001 Heverlee, Belgium; Université de 

Mons-Hainaut, 20, Place du Parc, B-7000 Mons, Belgium; Laboratory of Supramolecular Chemistry and 

Technology MESA+ Research Institute, University of Twente, P.O. Box 217, NL-7500 AE Enschede, The 

Netherlands) 

Self-assembly of electroactive polychlorotriphenylmethyl organic radicals on 

surfaces: molecular switches and molecular wires 

10H20-10H50 


58


Session 9 

Room Calendal 

Organic Nanostructures (Chairman: Porte) 

10H50-11H20 

ZANONI (1Dipartimento di Chimica, Università di Roma La Sapienza, p.le Aldo Moro, 5 - I 00185 Roma 

(Italy); 2Dipartimento di Chimica Organica e Industriale, Università di Parma, Parco delle Scienze 17/a, I-43100 

Parma (Italy)) 

Anchoring modes of calix[4,6]arene derivatives on Si(100) and polycrystalline 

copper 

11H20-11H40 

PATRONE (1 Aix-Marseille Université, IM2NP; 2 CNRS, IM2NP (UMR 6242); 3 Institut Supérieur de 

l‟Electronique et du Numérique, Maison des Technologies, Place Georges Pompidou, F-83000 Toulon, France) 

Single and binary monolayers of phenyl species with and without fluorine 

substitution self-assembled on SiO2 

11H40-12H00 

EL GARAH (FEMTO-ST 32 avenue de l‟Observatoire, F-25044 Besançon France) 

Large-scale patterning of zwitterionic molecules on a Si(111)-7x7 surface 

12H00-12H20 

DIRANI (Institut de Sciences des Matériaux de Mulhouse (IS2M –CNRS LRC7228) 15, rue Jean Starcky, BP 

2488, 68057 MULHOUSE Cedex, France) 

Block Copolymer Self-Assembly on Nanostructured Surfaces 

12H20-12H40 

VECIANA (1Institut de Ciencia de Materials de Barcelona -CSIC, Campus UAB, Bellaterra, Spain; 2CIBER- 

BBN, Campus UAB, Bellaterra, Spain; 3Institució Catalana de Recerca i Estudis Avançats , Barcelona, Spain; 

4Universitá dell‟Insubria, via Vallegio 11, 22100 Como, Italy.) 

Ultra Sensitive Piezoresistive All-Organic Flexible Thin-films and Strain Sensors 

based on Nanostructured Polymeric Composite Materials 

59


Wednesday, June 30 

Session 10 

Room Port-Pin 

Magnetic Nanostructuration (Chairman : ) 

8H30-9h10 FIORANI (ISM - CNR, Area ROMA 1, Via Salaria km 29.500, 00016 Roma, Italy ) 

Metallic Alloys for high density recording media 

9H10-9H30 

LE THANH (1 Centre Interdisciplinaire de Nanoscience de Marseille (CINaM-CNRS), Aix-Marseille 

Université, Campus de Luminy, case 913, 13288 Marseille, France, 2 Department of Electronic Engineering, the 

University of Electro-Communications, 1-5-1 Chofugaoka, Chofu-shi, Tokyo 182-8585, Japan) 

Mechanism and compositions of GeMn self-assembled nanocolumns. 

9H30-9H50 

DRZEWINSKI (aFaculty of Physics, A. Mickiewicz University, Poznań, Poland; bInstitute of Physics, 

University of Zielona Góra, Poland; cInstitute of Engineering and Computer Education, University of Zielona Góra, 

Poland; dDepartment of Chemistry, University of Wroclaw, Poland; dDepartment of Chemistry, University of 

Florence, Italy) 

DMRG approach to molecular-based alternating spin bimetallic chains 

9H50-10H10 

SCHLAGE (1DESY, Notkestr. 85, 22607 Hamburg, Germany; 2European Synchrotron Radiation Facility, BP 

220, 38043 Grenoble Cedex, France; 3TU München, Physik Department E13, 85747 Garching, Germany) 

Magnetic Fluctuations of Bit Cells in Self-Assembled Magnetic Nanopattern 

10H10-10H50 


60


Session 11 

Room Port-Pin 

Zn-Based-Nanostructures (Chairman: Grosso) 

10H50-11H20 

KUZNETSOV (Dept of Physics, University of Olso, P.O.Box 1048 Blindern, NO-0316 Oslo, Norway) 

Band gap engineering in ZnCdO nanostructures: synthesis, properties and 

applications 

11H20-11H40 

FARHADYAR (1) Department of Chemistry, Faculty of Basic Sciences,varamin –pishva Branch , Islamic 

Azad University,Iran, 2)Department of Chemistry, Faculty of Basic Sciences, Sciences and Research Campus, 

Islamic Azad University, Tehran Iran) 

Preparation of nanosize ZnO on the hollow silica matrix and study of it‟s 

photocalytic activity 

11H40-12H00 

SALIBA (a University of Toulouse, UPS, Bat 2R1, 118 route de Narbonne, 31062 Toulouse ; b Laboratoire de 

Chimie de Coordination; CNRS UPR 8241, 205 route de Narbonne, 31077 Toulouse) 

Liquid Crystalline-ZnO Nanoparticle Hybrids 

12H00-12H20 

GIRI (Department of Physics, Indian Institute of Technology Guwahati -781 039, India) 

Cobalt doping of ZnO nanoparticles by ball milling: Enhanced UV luminescence and 

room temperature ferromagnetism 

12H20-12H40 

GOUDARZI (aDept.of Polymer Engineering, Golestan University,Gorgan,Iran.,bDept.of Chemistry, 

University of Ilam, Ilam, cPolymer Science and Engineering Pusan National University, Busan 609-735,Republic of 

Korea) 

Study of Composition, Structure and Optical Properties of Nano-structured ZnS:Mn 

Thin Films Prepared by Chemical Deposition Method 

61

A B S T R A C T S WEDNESDAY, JUNE 30 N A N O S E A 2 0 1 0 

Room Calendal 

8H30-9h00 

Molecular diffusion processes in nanostructured organic thin films. 

C. Teicherta, G. Hlawaceka, S. Lorbeka, P. Puschnigb, C. Ambrosch-Draxlb, P. 

Frankc, T. Potocarc,A. Winklerc (a Institute of Physics, University of Leoben, A-8700 Leoben, Austria; 

b Chair of Atomistic Modelling and Design of Materials, University of Leoben, A-8700 Leoben, Austria; c Institute 

of Solid State Physics, Graz University of Technology, A-8010 Graz, Austria)teichert@unileoben.ac.at 


Crystalline films of conjugated organic semiconductors offer attractive potential for optoelectronic and 

electronic applications on flexible substrates. Due to the complexity and anisotropy of the molecular building 

blocks, novel growth mechanisms can occur as is demonstrated for the growth of the rod-like oligophenylene 

molecule parasexiphenyl (6P) on mica surfaces. On clean mica(001), the self-organization of crystallites into 

one-dimensional chains is observed on a wetting layer where the 6P molecules lie on the surface [1]. 


Here we demonstrate by atomic force microscopy that on an ion bombarded mica surface, the formation of 

terraced mounds composed by almost upright standing molecules is observed. Quantitative analysis of the 

morphology together with transition state theory calculations revealed the existence of level dependent step 

edge barriers and molecule bending during step edge crossing [2]. A lower barrier due to less molecular tilt 

in the first layer results in the completion of one monolayer before mound formation starts. By temperature 

and rate dependent growth experiments we also determined the size of the critical nucleus to be significantly 

larger than one. 


Our analysis showed that procedures developed and verified for inorganic systems [3] can be successfully 

applied to organic thin film growth. However, we have also demonstrated that the complexity and anisotropy 

of the molecular building blocks lead to additional effects that are not observed in atomic inorganic growth 

systems. 

[1] C. Teichert G. Hlawacek, A. Andreev, H. Sitter, P. Frank, A. Winkler, N.S. Sariciftci, Appl. Phys. A 82 (2006) 665. 

[2] G. Hlawacek, P. Puschnig, P. Frank, A. Winkler, C. Ambrosch-Draxl, C. Teichert, Science 321 (2008) 108. 

[3] T. Michely and J. Krug; Islands, Mounds and Atoms (Springer, Berlin 2004). 

62


9H00-9H20 

Valence band photoelectron spectroscopy of the Zn-Phthalocyanine/Ag(110) 

interface: Charge transfer and scattering of substrate photoelectrons. 

L. Giovanelli 1 , P. Amsalem 2 , T. Angot 3 , L. Petaccia 4 , S. Gorovikov 4 , L.Porte 1 , A. 

Goldoni 4 , and J.-M. Themlin 1 (1 IM2NP-CNRS, Aix-Marseille Université, Campus de St. Jérôme, 

Marseille, France, 2 Humboldt University, Institut für Physik, Newtonstraße 15, 12489 Berlin, Germany, 3 PIIM- 

CNRS, Aix-Marseille Université, Campus de St. Jérôme, Marseille, France, 4 ELETTRA, Sincrotrone Trieste, Area 

Science Park, S.S. 14, km 163.5, Basovizza (Trieste), Italy) 

The electronic properties of Zn-phthalocyanine vacuum-deposited on Ag(110) are studied by angular 

integrated valence band photoelectron spectroscopy. The experiment was performed at the BaD ElPh 

beamline at the Elettra synchrotron radiation facility. Sub-monolayer, one ordered monolayer and molecular 

layers of increasing thickness present spectral features that can be related to the molecule-substrate 

interaction as well as to the effect of the overlayer on the escape conditions of the substrate photoelectrons. 

For the first, ordered molecular monolayer, an interface state related to a charge transfer from the substrate to 

the molecules is detected through the appearance of a new feature at low binding energy. Such feature is 

interpreted as the partial filling of the lowest unoccupied molecular orbital (LUMO). Its lineshape is 

addressed in detail and interpreted as a possible hybridization of the LUMO with substrate states as well as 

photohole-vibron coupling and correlation effects. Decreasing the temperature down to about 20 K causes an 

overal shift to higher binding energies of the interface state. A preliminary explanation is given in terms of 

Jahn-Teller distortions. Molecular states lying at higher binding energy show little or negligible modification 

as a function of coverage testifying of a weak contribution in the molecule-substrate interaction. Important 

changes are found in the spectral region of the Ag 4d bands after the deposition of a sub-monolayer and as a 

function of coverage. However, these changes are not interpreted by the formation of new interface states. 

Rather, it is shown that these features can be entirely explained by considering the effect of the molecular 

overlayer on the escape conditions of the substrate photoelectrons. The effect is the emergence of the 

substrate 3D density of states. We argue that such behaviour is expected to apply to other organic adsorbates 

over single crystal surfaces. 

9H20-9H40 

Phthalocyanine induced nanostructuring of the Au(110) surface. 

T. Pertram, J. M. Essen, S. Le Moal*, M. Moors, M. Peintinger, C. Becker*, T. 

Bredow and K. Wandelt (Institute of Physical and Theoretical Chemistry, University of Bonn, 

Wegelerstr.12, D-53115 Bonn, Germany, *CINAM – CNRS – UPR 3118, Aix-Marseille Université, Campus de 

Luminy – Case 913, F-13288 Marseille, France)tpertram@uni-bonn.de 

The {110} surfaces of fcc metals exhibit an intrinsic anisotropy due to their rectangular surface unit cell. 

This anisotropy is even more pronounced in case of the (1x2) missing row reconstruction, which is typical 

for the Au(110) surface. We have used this reconstructed surface as a substrate for the ordered (“templated”) 

deposition of phthalocyanine molecules. 

Phthalocyanines, planar aromatic macrocycles, have attracted considerable attention owing to their 

promising application in optical and electronic devices. Especially the adsorption behaviour and film growth 

have been investigated in an attempt to offer new nanotechnological and nanoelectronic materials. 

63


Our STM and LEED investigations reveal a specific adsorption behaviour of the metal-free phthalocyanine 

molecules. At room temperature the adsorption of the molecules leads to the formation of double rows, 

which run in the direction of the close-packed gold atom rows. Beneath these double rows, the reconstruction 

of the supporting gold is changed from a (1x2) to a (1x3) structure by the adsorption of the phthalocyanine 

molecules. An additional long range periodicity, perpendicular to the molecular rows, is observed at higher 

coverage. Namely, one (1x3) trough filled with molecules is alternating with two (1x2) unit cells. The 

coexistence of (1x2) and (1x3) troughs is confirmed by LEED observations. 

This system can neither be described by the classical models of substrate induced structure formation nor by 

molecular self assembly, but by a cooperative effect. The formation of double rows on the (1x3) 

reconstructed Au(110) surface is triggered by both a strong molecule-molecule interaction and a strong 

molecule-substrate interaction. In contrast only a weak interaction between adjacent dimers along the rows 

could be observed, the closest distance between them equals six times the Au lattice constant. 

9H40-10H00 

Self-organized Porphyrin monolayers on halide-modified noble metal surfaces. 

M. Schneider, T. Kosmala, K. Wandelt (Institute of Physical and Theoretical Chemistry, University 

of Bonn - Wegelerstr. 12 D-53115, Bonn, Germany)schneider@pc.uni-bonn.de 

In the field of template chemistry, new and interesting phenomena can be discovered at gold/electrolyte 

interfaces in the presence of anions and supramolecules as function of electrode potentials. The phase 

transitions of iodine adsorbate layers on gold surfaces allow us to study the influence of template effects of 

first and second order on the self-organisation of porphyrins. 

Halide-modified gold surfaces are desirable substrates due to their long range order. Iodide-modified 

Au(111)-surfaces show phase transitions (from (√3x√3)R30° over c(px√3) to rotated-hexagonal) and 

electrocompression dependent on the electrode potential. 

Porphyrins are important organic compounds in the fields of biology and technology. They open a series of 

potential applications in cancer therapy, or as catalysts and sensors. Specifically, Tetra(N-methyl-4-pyridyl)- 

porphyrin molecules (TMPyP) form various rectangular structures on iodine-modified Au(111) and Cu(111) 

surfaces. 

Our studies with STM and cyclic voltammetry not only reproduce previous works about TMPyP on iodidemodified 

Au(111)-surfaces, but provide an even more precise understanding. Namely, it is found that the 

TMPyP layer exhibits a long-range periodic superstructure beyond the molecular arrangement. 

This research complements one of our previous studies regarding adsorption of the same molecule on halide 

modified copper surfaces, allowing comparisons between systems with the same molecule but different 

substrates. Beyond the similarities in molecular arrangement, the long-range periodic superstructure found in 

our recent works is a novelty. 

64


10H00-10H20 

Self-assembly of electroactive polychlorotriphenylmethyl organic radicals on 

surfaces: molecular switches and molecular wires. 

M. Mas-Torrent, N. Crivillers, C. Simao, J. Veciana, C. Rovira, C. Ocal, S. De 

Feyter, R. Lazzaroni, B. J. Ravoo (Institut de Ciència de Materials de Barcelona (CSIC), Campus de la 

UAB E-0183, Bellaterra, Spain; Katholieke UniVersiteit LeuVen, Celestijnenlaan 200-F, 3001 Heverlee, Belgium; 

Université de Mons-Hainaut, 20, Place du Parc, B-7000 Mons, Belgium; Laboratory of Supramolecular Chemistry 

and Technology MESA+ Research Institute, University of Twente, P.O. Box 217, NL-7500 AE Enschede, The 

Netherlands)mmas@icmab.es 

The ultimate goal of molecular bottom up approaches is to employ functional building blocks to construct 

nanometer scale devices addressed to specific applications. Furthermore, for device implementation the 

immobilisation of functional molecules on surfaces is also often required. Here, we describe the preparation 

of self-assembled monolayers (SAMs) of polychorotriphenylmethyl (PTM) radicals on different substrates 

(SiO2, Au and ITO).[1-2] 

The family of PTM radicals is highly stable due to the fact that their open-shell centres are shielded by six 

bulky chlorine atoms.[3] These radicals are colored and also exhibit fluorescence in the red region of the 

spectra. PTM radicals are also electroactive and can be easily and reversibly reduced (or oxidized) to their 

anionic (or cationic) species. The oxidised and reduced states show different absorption spectra than the 

radical and are in addition non magnetic and non fluorescent. Thus, the preparation of SAMs functionalised 

with PTM radicals on substrates results in multifunctional surfaces which are electrochemically, optically 

and magnetically active. We also demonstrate that these SAMs can be used as chemical and electrochemical 

redox switches with optical and magnetic responses. 

Also, very recently two different SAMs based on the closed and open-shell form of a PTM derivative were 

prepared and the conductivity through these SAMs was investigated by the 3D mode SFM.[4] These two 

systems exhibited small differences in their molecular structure but large differences in the electronic 

structure, which dramatically influenced the transport properties, being the radical SAMs much more 

conducting than the close-shell form. 

The self-assembly of novel PTM radicals bearing long alkyl chains at the liquid-graphite interface was also 

investigated. We show that the PTM hierarchical self-assembles giving rise to 3-dimensional ordered 

nanostructures forming double rows composed by a magnetic core of radicals surrounded by alkyl chains.[5] 

The fabrication of ordered surface nanostructures of multifunctional organic radicals represents an important 

step forward in the field of molecular electronics and molecular magnetism. 

[1] N. Crivillers et al. Angew. Chem. Int. Ed. 46 (2007) 2215. 

[2] N. Crivillers et al. J. Am. Chem. Soc. 130, (2008) 5499. 

[3] M. Ballester et al. J. Am. Chem. Soc. 93, (1971) 2215. 

[4] N. Crivillers, et al., Adv. Mater., 21 (2009) 1177. 

[5] N. Crivillers et al. J. Am. Chem. Soc. 131, (2009) 6246. 

65


10H50-11H20 

Anchoring modes of calix[4,6]arene derivatives on Si(100) and polycrystalline 

copper. 

A. Boccia1, V. Di Castro1, V. Lanzilotto1, R. Zanoni1*, A. Arduini2, L. Pescatori2, 

A. Pochini2, and A. Secchi2 (1Dipartimento di Chimica, Università di Roma La Sapienza, p.le Aldo 

Moro, 5 - I 00185 Roma (Italy); 2Dipartimento di Chimica Organica e Industriale, Università di Parma, Parco delle 

Scienze 17/a, I-43100 Parma (Italy)) *robertino.zanoni@uniroma1.it 

The controlled production of organic monolayers on semiconductor and metal surfaces of technological 

interest can provide a material with new features in the nanoscale. While numerous examples have been 

already proposed of functional species, such as redox couples, bio-molecules or selective receptors anchored 

on silicon or on gold surfaces, very rarely a close comparison has been reported of the behaviour of a class of 

such compounds on both a semiconductor and metal surface. The first compared study is given here of the 

distinct anchoring properties on H-Si(100) and polycrystalline Cu of a few members of a class of molecules, 

chosen among the most representative ones in supramolecular chemistry: calix[n]arenes.[1] Calixarenes have 

been chosen for their flexibility as linkers, being, i.e., efficient building blocks for constructing molecular 

devices based on rotaxanes. A covalent functionalization on both Si and Cu surfaces requires the molecules 

to be differently modified: thiol (-SH) or C=C terminations are respectively suitable for copper or H-Si(100). 

Anchoring on Cu was reached by dipping a clean sample in a calix[n]arene solution (n=4,6), while a wet 

chemistry recipe was followed for Si(100), combined with an extra-mild photochemical activation via visible 

light.[2] Molecular adhesion onto either surfaces has been demonstrated by the presence of XPS signals from 

specific elements in the molecules: calix[4,6]arene designed for H-Si were derivatized with Br atoms or NO2 

groups on the upper rim of the calix, while the S atom was used as the molecular identifier on Cu.[3] AFM 

measurements performed on H-Si(100)/calix[4]arene have revealed structures 2-2.5 nm high, consistent with 

the length of the molecule in a standing up conformation. The diameter of these structures suggests that selfassembled 

calixarenes clusters are formed on Si. The availability of the calix[4]arene cavity to host further 

species after anchoring on Si has been demonstrated by the successful complexation reaction with Cs+ ions, 

resulting in a 1:1 calix/Cs+ ratio. A further extension on Cu is represented by anchoring a rotaxane. A 

pseudorotaxane species was formed in solution by reacting a calix[6]arene wheel, derivatized with N- 

phenylureido groups on the upper rim, with viologen (4,4‟-bipyridinium) containing axle.[4] The resulting 

species has been anchored on Cu via the -SH termination of the axle. This twostep reaction has produced a 

threaded rotaxane covalently bound to Cu surface, as shown by XPS results. This species is ready to respond 

to external stimuli. 

11H20-11H40 

Single and binary monolayers of phenyl species with and without fluorine 

substitution self-assembled on SiO2. 

Lionel Patrone 1,2,3, Virginie Gadenne 1,2,3 and Simon Desbief 1,2,3 (1 Aix-Marseille 

Université, IM2NP; 2 CNRS, IM2NP (UMR 6242); 3 Institut Supérieur de l‟Electronique et du Numérique, Maison 

des Technologies, Place Georges Pompidou, F-83000 Toulon, France)lionel.patrone@im2np.fr, 

virginie.gadenne@im2np.fr 


Among various strategies, molecular self-assembly [1,2] is one of the most promising issues for giving 

surface specific properties. An important field of application of self-assembled monolayers (SAMs) [2] is 

molecular electronics within which self-assembly is a very powerful way to obtain the organization at large 

66


surface scale of molecules showing particular electronic properties (insulator, molecular wire, memory, 

diode, …) [3]. Using silicon as a SAM substrate appears to be a promising challenge in molecular 

electronics. Indeed, this hybrid approach benefits from both the well-developed silicon technology and the 

specific properties of molecules. Therefore, preparation of self-assembled monolayers of aromatic 

conjugated molecules on silicon is a key point in molecular electronics [4]. Moreover, regarding potential 

applications, it is important to be able to prepare nano-islands of such active molecules on silicon. 

Nevertheless few works addressed this subject [5]. To achieve these two points, strong interactions between 

aromatic molecules are mandatory. Varying these interactions in order to identify the right interaction 

strength suitable for preparing dense aromatic SAMs either at a large surface scale or within nano-islands is 

the scope of this work. For this purpose we used two aromatic molecules bearing a phenyl ring on a small 

alkyl chain, with (Fig. 1b) and without (Fig. 1a) fluorine substitution. 

F 

F 

Cl 

Si Cl 

Cl 

F 

F 

F 

Cl 

Cl 

Si 

Cl 

Figure 1. Aromatic trichlorosilane molecules used in this study: (a) phenylbutyltrichlorosilane (PBTCl), 

(b) pentafluoro-phenylpropyltrichlorosilane (FPPTCl). 


In a first part of our work, in order to control the formation of conjugated molecular nano-domains on native 

oxide covered silicon, we studied how various tri-functionalized silane molecules bearing a phenyl cycle, 

modified or not, interact during their self-assembly [6]. 

Concerning phenyl rings without alkyl chain, SAM growth is shown to occur in a single step: chemisorption 

on the surface. This step is thermally activated and does not depend on ring to ring interactions. We show 

that adding a short alkyl chain (3-4 carbon atoms) to the phenyl ring gives the molecules enough flexibility 

to generate an additional second growth step. The latter is independent from the deposition temperature and 

corresponds to the arrangement between molecules. We found that this packing step is accelerated by 

replacing phenyl by pentafluoro-phenyl rings, possibly due to quadrupolar interactions between fluorinated 

cycles. Furthermore we demonstrate that mixing phenyl and pentafluoro-phenyl molecules leads to an even 

faster packing step which is accounted for by hydrogen bonding CH FC in a face to face 

phenyl/pentafluoro-phenyl arrangement [7,8,9]. We believe these results allow improving charge 

delocalization over conjugated molecular domains. 

In a second part, we studied the phase separation between phenyl-alkylsilane and octadecyltrichlorosilane 

(OTS) molecules. Improving the phase separation was studied using two parameters: ring to ring interactions 

afore-analyzed and reactive heads with different grafting kinetics. Using the same trichlorosilane grafting 

moiety for phenyl molecules as for OTS, we show that phase separation is improved and OTS islands are 

smaller with phenyl species that involve stronger ring to ring interactions. The best case is obtained with 

mixing phenyl and pentafluoro-phenyl rings using hydrogen bonds for packing together the aromatic species 

of the SAM. Small phenyl species islands (40-100 nm in diameter) could be obtained inside the OTS SAM 

using a less reactive grafting head for the aromatic molecules. These two cases demonstrate an improved 

control of SAM composition and morphology essential to further use the obtained islands for building 

molecular devices. 

67



We have shown that the growth on silicon dioxide of SAMs of short phenyl-alkyltrichlorosilane species 

exhibits two steps: chemisorption depending on the grafting head, and a longer step of densification 

depending on the interactions involved between phenyl rings This second step is about height times quicker 

by introducing hydrogen bonding between phenyl rings while mixing phenylbutyltrichlorosilane and 

pentafluoro-phenylpropyltrichlorosilane molecules. Moreover, the interactions between aromatic rings in the 

monolayer modify the composition of the final SAM prepared with OTS. These interactions between phenyl 

rings impact on the size and quantity of alkyl nano-domains and moderate interactions can improve phase 

separation with the alkyl chains. Further work is addressed to improve this control. In particular, mixing 

molecules with reactive moieties having different grafting kinetics may offer another possibility to control 

the SAM structure and composition. 

Acknowledgments 

Equipment used for this study was mainly funded by the “Objectif 2” EEC program (FEDER), the “Conseil 

Général du Var” Council, the PACA Regional Council and Toulon Provence Méditerranée which are 

acknowledged. 

References 

1. G.M. Whitesides, B. Grzybowski, Science 295, 2418 (2002). 

2. A. Ulman, An introduction to ultrathin organic films (Academic Press: Boston, 1991) 

3. H.B. Akkerman et al., Nature 69, 441, (2006). 

4. M. Halik, H. Klauk, U. Zschieschang, G. Schmid, C. Dehm, M. Schütz, S. Maisch, F. Effenberger, M. Brunnbauer, F. Stellacci, Nature 431, 963 

(2004) 

5. F. Fan, C. Maldarelli, A. Couzis, Langmuir 19, 3254 (2003) 

6. J. Moineau et al., Langmuir 20, 3202, (2004). 

7. V.R. Thalladi et al., J. Am. Chem. Soc. 120, 8702, (1998). 

8. J.D. Dunitz, ChemBioChem. 5, 614 (2004). 

9. S. Zhu et al., Tetrahedr. Lett. 46, 2713, (2005). 

11H40-12H00 

Large-scale patterning of zwitterionic molecules on a Si(111)-7x7 surface. 

M. El Garah, Y. Makoudi, E. Duverger, F. Chérioux, F. Palmino, A. Rochefort 

(FEMTO-ST 32 avenue de l‟Observatoire, F-25044 Besançon France) mohamed.elgarah@pu-pm.univ-fcomte.fr 


Achievement of a large scale organic nano-structured pattern on semiconductors at room temperature is a 

major goal to realize molecular electronic nano-devices. To overcome the problem of the high reactivity of 

the Si(111)-7×7 reconstruction versus electron-rich molecules, original zwitterionic molecules were used.[1] 

The formation of a large scale pattern is successfully obtained thanks to the match of the molecular geometry 

with the surface topology and to electrostatic interactions between molecules and surface. 


High resolution STM images of MSP/Si(111)-7×7 surface carried out at room temperature and obtained, for 

a coverage 0.35 ML (Figure). 49% of single protrusions, 14% of couple protrusions and 37% of triangular 

nano-structures constituted by three protrusions are observed. One protrusion is attributed to one molecule 

adsorbed over the rest-atoms and out of the plane of the substrate. According to their negative charge, the 

68

Z[nm] 


sulfonato groups (SO3-) point towards the electrophilic surface. The three 

oxygen atoms interact with three adjacent Si adatoms thanks to an attractive 

electrostatic force. However, molecules are stabilized at an equilibrium distance 

above the surface due to the repulsive interaction between (SO3-) and the 

negatively charged rest-atom. 

Fig.1 STM image of MSP on Si(111)-7x7surface (I=0.013 nA, V=1.7 v) 

3 – Conclusion: 

A large molecular organic paving has been achieved at room temperature by two dimensional template 

effects of the highly reactive Si(111)-7×7. We have demonstrated that the MSP molecules are adsorbed onto 

the surface by electrostatic interactions between the local charges of the Si atoms and the negative sulfonato 

groups. 

12H00-12H20 

Block Copolymer Self-Assembly on Nanostructured Surfaces. 

DIRANI Ali, DIKA Ihab, SOPPERA Olivier (Institut de Sciences des Matériaux de Mulhouse 

(IS2M –CNRS LRC7228) 15, rue Jean Starcky, BP 2488, 68057 MULHOUSE Cedex, France) 

olivier.soppera@uha.fr, ali.dirani@uha.fr 

Block copolymer lithography harnesses the power of chemistry to reduce feature size even further, 

potentially smaller than 10 nm. Block copolymers have been proposed for many applications based 

Image 500 nm x 500 nm 

Topography 

2 

1.5 

1 

0.5 

0 

0 

20 

40 

35 nm 

60 

80 

X[nm] 

100 

120 

Block copo 

PS-PMMA 

140 

160 

Au 

180 

300 nm 

principally on their ability to form regular nanometer-scale 

patterns. These self-assembled patterns have been considered 

as nanolithographic masks as well as templates for the further 

synthesis of inorganic or organic structures. So far, the main 

limitation for practical applications has been due to the lack of 

order at long distance and much work has been done to control 

the self-assembly and orientation of block copolymers. 

Patterned substrates with length scales comparable to the 

natural periodicity of the block copolymer were used to 

control the orientation of the nanodomains of the block 

copolymer. 

Au patterns with trenches ranging from 100 to 1000 nm were 

prepared by DUV lithography, Au deposition and lift-off. 

Block copolymer thin films were deposited on these 

nanopatterned substrates and annealed. They consisted in P(Sb-MMA) 

block copolymers with various molecular weights. 

The typical lateral size of the blocks was 35 nm. 

Image 500 nm x 500 nm 

Phase 

Image 2µm x 10 µm 

Phase 

69


The impact of the wideness and the height of the trenches on the block copolymer domains order were 

investigated. The effect of the polymer chains length was also studied. 

It was demonstrated that the order can be insured on length in the range of few hundreds of µm, illustrating 

the potential of this technique for nanofabrication. From fundamental point of view, this work constitutes a 

contribution to further understanding the phenomena leading to the self-assembly of block copolymers in 

nanoconfined volumes. These surfaces were then use for the controlled deposition of nanoparticles for 

applications in data storage, demonstrating the interest of this approach from a practical point of view. 

12H20-12H40 

Ultra Sensitive Piezoresistive All-Organic Flexible Thin-films and Strain 

Sensors based on Nanostructured Polymeric Composite Materials. 

J. Veciana,1,2E. Laukhina,2,1 R. Pfattner,1,2 L.R. Ferreras,1,2 V. Laukhin,3,,1,2.S. 

Galli,4 M. Mas-Torrent,1,2 N. Masciocchi,4 V. C. Rovira,1,2 (1Institut de Ciencia de 

Materials de Barcelona -CSIC, Campus UAB, Bellaterra, Spain; 2CIBER-BBN, Campus UAB, Bellaterra, Spain; 

3Institució Catalana de Recerca i Estudis Avançats , Barcelona, Spain; 4Universitá dell‟Insubria, via Vallegio 11, 

22100 Como, Italy.). vecianaj@icmab.es 

The development of intelligent materials that can respond to the application of an external stimulus is of 

major interest for the fabrication of artificial sensing devices able to sense and transmit information about the 

physical, chemical and/or biological changes produced in our environment. In addition, if these materials can 

be deposited or integrated on flexible and transparent substrates and processed employing low-cost bottomup” 

techniques their appeal is greatly increased 

Here, we show that by using bi-layer (BL) films, composed of a polymeric matrix with a top-layer formed by 

a network of nano- or micro crystals of a conducting molecular charge-transfer salt, it is possible to translate 

micron-scale elastic elongations of the film into reversible deformations of the soft organic charge-transfer 

salt crystals at the nanoscale.1 These multiple length scale movements, from the micro to the nano scale, are 

responsible of the ultra sensitive piezoresistive properties of the BL films that are extremely sensitive to 

strain changes with durable, fast and completely reversible responses. Such BL films that show a sensitivity 

one order of magnitude larger than the most commonly used electromechanical sensors have integrated in 

textiles as well as in other surfaces exhibiting the same ultrasensitive piezoresistive sensitivity. In addition, a 

few proof-of-concept experiments with simple prototypes for biomedical applications will be reported. 

1 E. Laukhina et al., Adv. Mater. 2010, 24, in press. DOI: 10.1002/adma.200902639 

70


Room Port-Pin 

8H30-9h10 

Metallic Alloys for high density recording media. 

D. Fiorani, G. Varvaro, S. Laureti, E. Agostinelli, A.M. Testa (ISM - CNR, Area ROMA 1, 

Via Salaria km 29.500, 00016 Roma, Italy ) dino.fiorani@ism.cnr.it 


Magnetic recording represents one of the most rapidly developing high technology areas. The computer hard 

disk drive has experienced an exponential increase in data capacity over time making it the predominant 

storage system for digital data [1]. This high growth rate has imposed more and more pressing requirements 

for the recording media and has driven the research and the development of new systems in order to get the 

better trade-off among three fundamental requirements (recording trilemma): thermal stability, medium 

signal-to-noise ratio and writability. 


The most promising materials (e.g. L10-Co(Fe)Pt films, [Co/Pd]n multilayers, CoCrPt@SO2 films), 

recording modes (e.g. perpendicular recording, thermally assisted writing), architectures (e.g. tilted and 

exchange spring media) and designs (e.g. patterned media) of recording media will be rewieved. The 

investigation, by using a vectorial VSM, of the magnetic properties of two different materials for 

perpendicular recording (tilted easy axis L10-CoPt(111)/Pt(111)/MgO(100) films and perpendicular easy 

axis [(Co90Cr10)80Pt20]92:(SiO2)8 media) will be reported. 

(111) oriented films of the L10-CoPt alloy have been deposited by using a conventional frontal Pulsed Laser 

Deposition. A very thin Pt (111) underlayer has been grown on MgO(100) and used to favour the epitaxial 

growth of the magnetic layer along the [111] direction, i.e. with the c-axis tilted at an angle of 36° with 

respect to the film plane. From the analysis of the angular dependence of the remanent magnetization, it has 

been found that the system presents 4 out-of-plane 36° easy axes with orthogonal in-plane projections. 

[(Co90Cr10)80Pt20]92@(SiO2)8 films have been grown by magnetron sputter deposition onto thermally 

oxidised Si wafers. A complex seed layer stack – Cr(5nm)/Ru(8nm)/Ru(12nm) – has been used to promote a 

perpendicular anisotropy. The experimental data indicate that both Stoner-Wohlfarth and Kondorsky reversal 

mechanism are present, with a predominance of the Kondorsky character with decreasing magnetic layer 

thickness. 


The role of the metallic alloys in high density magneto-recording has been reported with particular emphasis 

on tilted easy axis L10-CoPt(111)/Pt(111)/MgO(100) films and perpendicular easy axis 

[(Co90Cr10)80Pt20]92:(SiO2)8 media. 

[1] H. J. Richter and A. Y. Dobin, J. Magn. Magn. Mater. 287, 41 (2005) 

71


9H10-9H30 

Mechanism and compositions of GeMn self-assembled nanocolumns. 

LE THANH (1 Centre Interdisciplinaire de Nanoscience de Marseille (CINaM-CNRS), Aix-Marseille 

Université, Campus de Luminy, case 913, 13288 Marseille, France, 2 Department of Electronic Engineering, the 

University of Electro-Communications, 1-5-1 Chofugaoka, Chofu-shi, Tokyo 182-8585, Japan) 

9H30-9H50 

DMRG approach to molecular-based alternating spin bimetallic chains. 

DRZEWINSKI - P. Sobczak a , A. Barasiński b , R. Matysiak c , A. Drzewiński b , G. 

Kamieniarz a , J. Kłak d , A. Bieńko d , J. Mroziński d , D. Gatteschi e (aFaculty of Physics, A. 

Mickiewicz University, Poznań, Poland; bInstitute of Physics, University of Zielona Góra, Poland; cInstitute of 

Engineering and Computer Education, University of Zielona Góra, Poland; dDepartment of Chemistry, University of 

Wroclaw, Poland; dDepartment of Chemistry, University of Florence, Italy) 


Molecular magnets, including bimetallic chain systems, can be numerically analysed on the basis of the 

anisotropic quantum Heisenberg model [1]. To cover the entire experimental 1.7 − 300 K temperature range, 

the density-matrix renormalization group (DMRG) approach is very appealing. It has been exploited in the 

molecular nanomagnetism for the first time, analysing the experimental results for a number of compounds 

with the thiocyanate bridges without the mean-field corrections [1]. 


At first, a series of one-dimensional compounds comprising square planar tetraazamacrocycle copper(II) 

building blocks forming Cu(II)-SCN-M-NCS-Cu(II) chains, where M = Co, Ni, Mn, is reported. Although 

the thiocyanate ligands are weak magnetic mediators, both the ferromagnetic and antiferromagnetic 

interactions occur in our compounds and are not negligible [1]. The approach is applied also to the Re(IV) – 

Cu(II) complex [Cu(tren)]ReCl 6·2CH 3 OH, where both the exchange interaction J and the D zero-field 

splitting are expected to be much stronger [2]. 

The high accuracy results of our simulations have been fitted to the corresponding experimental 

susceptibility and magnetization data. To get an appropriate set of parameters, we always fitted both the 

magnetic susceptibility curves and the magnetization profiles to our numerical results. 

[1] A. Barasinski et al, Polyhedron (2010), doi: 10.1016/j.poly.2010.01.002 

[2] A. Tomkiewicz, et al, Journal of Molecular Structure 644, 97 (2003) 


For all the compounds, both the experimental susceptibility and field-dependent magnetization data have 

been fitted successfully using the quantum model without the mean-field corrections, leading to the sets of 

model parameters (the strength of magnetic couplings, the single-ion anisotropy terms and the corresponding 

g factors). The corresponding values for the Re(IV) – Cu(II) compound are the following: J/k B = 3.5 ± 0.5 K, 

D/k B = 35 ± 5 K, g Cu = 2.07 ± 0.05, g Re = 1.73 ± 0.01 

72


9H50-10H10 

Magnetic Fluctuations of Bit Cells in Self-Assembled Magnetic Nanopattern. 

1,*Kai Schlage, 1Sebastien Couet, 1Stephan V. Roth, 1Ulla Vainio, 2Rudolf Rüffer 

3,1Mottakin M. Abul Kashem, 3Peter Müller-Buschbaum and 1Ralf Röhlsberger 

(1DESY, Notkestr. 85, 22607 Hamburg, Germany; 2European Synchrotron Radiation Facility, BP 220, 38043 

Grenoble Cedex, France; 3TU München, Physik Department E13, 85747 Garching, Germany)* kai.schlage@desy.de 


On the way towards ultimate magnetic storage densities, self-organized ordered polymer nanostructures 

appear to be very promising templates for the growth of magnetic nanodot arrays covering almost arbitrary 

large areas with nanoscopic unit cells down to a few nanometre. It is obvious that the maximum density of 

separated magnetic nanodots is limited by the superparamagnetic effect when the moments of the dots 

become subject to thermal fluctuations. 


This limit can be overcome by replacing the dot array by its inverse structure, the antidot array. Tailoring the 

magnetic properties of such structures requires a deep knowledge of the interplay between structure, 

chemistry and magnetism. Here we apply a new kind of 3D microscopy combining high-resolution x-ray 

scattering techniques to track all these key parameters during growth of this self-assembled magnetic 

nanostructure. A strong selective 3D wetting of iron on the nanostructured polymer template, the formation 

of an ultra-thin single-phase oxide layer in contact to the polymer and a unique transition beyond the 

superparamagnetic limit of the resulting iron antidot array are directly observed. 


The results are expected to have a high impact on the fabrication process of magnetic nanostructures not only 

for fundamental research but also for realization of magnetic data storage devices. 

10H50-11H20 

Band gap engineering in ZnCdO nanostructures: synthesis, properties and 

applications. 

A.Yu.Kuznetsov, V.Vishnukanthan, M.Trunk, T.Zhang, A.Azarov, A.Galeckas (Dept 

of Physics, University of Olso, P.O.Box 1048 Blindern, NO-0316 Oslo, Norway) andrej.kuznetsov@fys.uio.no 

Oxide semiconductors in general and ZnO-based semiconductors in particular have attracted much of 

attention on behalf of unique properties having promising applications in advanced electronic and 

optoelectronic devices. For example, realizing novel band-to-band absorbers made of reasonably cheap 

materials is a challenge in photovoltaics and – highlighting just one of ZnO potentials – band gap 

engineering in ZnO-based materials can actually answer this challenge. Indeed, alloying ZnO with CdO 

results in a gradual band gap shrinking in the range of 3.3-1.8 eV as a function of Cd content. Moreover, 

pure ZnO may be readily synthesized in various forms of nanowires (NWs) and manufacturing of ZnCdO 

NWs having a graded concentration/bandgap is interesting to research too. 

In the frame of this work we are making a systematic effort to manufacture and study ZnCdO, synthesizing 

high quality crystalline samples using metal organic vapor phase epitaxy and targeting both multilayer (ML) 

and NW structures. The fundamental result reached so far is in realization of graded ZnCdO ML 

73


nanostructures as well their characterization employing a variety of methods. As an example, please find two 

diagrams below illustrating (a) - photoluminescence measurements and (b) - chemical composition depth 

profiling in typical ML nanostructures (note, Cd content is deduced from Rutherford backscattering 

spectroscopy results). The work on realization of graded ZnCdO NWs is in progress. 

74


11H20-11H40 

Preparation of nanosize ZnO on the hollow silica matrix and study of it’s 

photocalytic activity. 

1 N. Farhadyar*, 2 M. S. Sadjadi (1) Department of Chemistry, Faculty of Basic Sciences,varamin –pishva 

Branch , Islamic Azad University,Iran, 2)Department of Chemistry, Faculty of Basic Sciences, Sciences and 

Research Campus, Islamic Azad University, Tehran Iran) nfarhadyar@gmail.com 

High efficiency of photocatalystic reaction has achieved by increasing the surface area of the support of the 

photocatalyst nanosize materials. Therefore, controlling of the crystalline size of the support materials is very 

crucial to monitor adequately the catalytic activity or enhancement of the photocatalytic activity on the 

hollow materials. It seems to be attractive in use of nanosized ZnO on the hollow silica. 

In this work, nanosized ZnO on the hollow silica was prepared from precursors zinc acetate as zinc source 

and loaded on the hollow silica by using tetraethoxysilane. As prepared material, nanosized ZnO on the 

hollow silica was investigated by using X-ray diffraction (XRD), Transmission electron microscopy (TEM), 

Fourier transform infrared spectroscopy (FT- IR). Photocatalytic activity of the samples, of nanosized ZnO 

on the hollow silica were finally evaluated by degrading of the methyl orange under irradiation of UV light. 

The results showed that the nanosized of nanosized ZnO on the hollow silica enhances the photocatalytic 

activity of ZnO when loaded on Hollow silica. 

11H40-12H00 

Liquid Crystalline-ZnO Nanoparticle Hybrids. 

S. Saliba,a,b J.-D. Marty,a M. L. Kahn,b Y. Coppel,b C. Mingotaud,a B. Chaudret b 

(a University of Toulouse, UPS, Bat 2R1, 118 route de Narbonne, 31062 Toulouse ; b Laboratoire de Chimie de 

Coordination; CNRS UPR 8241, 205 route de Narbonne, 31077 Toulouse) 


ZnO is a well known wide-gap semiconductor with a band-gap value of 3.37 eV displaying luminescent 

properties in the near UV and visible regions of the spectrum.1 Such nanoparticles (Nps) are highly 

interesting in the manufacture of electronic and photonic devices.2,3 Combining ZnO Nps and liquid crystals 

(LCs) may lead to new hybrids with unique properties and controlled organization. To elaborate such 

materials two strategies can be envisaged; a) mixing preformed ZnO Nps with a compatible LC and b) the 

in-situ growth of Nps inside the liquid crystalline host. We have developed both strategies using the 

thermotropic liquid crystal 4‟-(6-aminohexyloxy) biphenyl-4-carbonitrile (6OCBNH2) as host and obtained 

new organic/inorganic organized materials. 

75



The general synthesis of ZnO NPs is being carried out via a straight forward organometallic method 

previously reported by our group. Generally using octylamine (OA) as ligand, Nps with an average diameter 

of 4 nm are obtained.4 

First strategy involved the mixing of a solution of OA-protected ZnO nanoparticles with a solution of 

6OCBNH2. The ligand exchange was confirmed by 1H-NMR and DOSY experiments. Dispersion of these 

Nps in 6OCBNH2 did not disrupt the mesomorphic behavior of the latter as proven by DSC and POM. The 

mixing does not quench the optical properties of ZnO and we therefore obtain a hybrid material that exhibits 

interesting emission properties in the UV region of the spectrum. 

The second strategy was the direct synthesis of ZnO Nps in 6OCBNH2. This has resulted in the formation of 

well dispersed spherical nanoparticles of an average diameter of 5 nm. The formation of ZnO inside the LC 

host had no unfavorable effects on the luminescent properties of ZnO. Emissions corresponding to a variety 

of regions in the visible spectrum depending on excitation wavelength were observed. The liquid 

crystalline properties of this hybrid are being studied in depth. 


To our knowledge we have developed novel liquid crystal hybrid materials containing ZnO nanoparticles. 

Besides their interesting optical properties, we have the possibility to control the organization of particles 

using the alignment properties of the LC. 

References 

(1) Huang, M. H.; Mao, S.; Feick, H.; Yan, H. Q.; Wu, Y. Y.; Kind, H.; Weber, E.; Russo, R.; Yang, P. D. Science 2001, 292, 1897-1899. 

(2) Rodriguez, J. A.; Jirsak, T.; Dvorak, J.; Sambasivan, S.; Fischer, D. J. Phys. Chem. B 2000, 104, 319-328. 

(3) Noack, V.; Weller, H.; Eychmuller, A. J. Phys. Chem. B 2002, 106, 8514-8523. 

(4) Monge, M.; Kahn, M. L.; Maisonnat, A.; Chaudret, B. Angew. Chem.-Int. Edit. 2003, 42, 5321-5324. 

12H00-12H20 

Cobalt doping of ZnO nanoparticles by ball milling: Enhanced UV 

luminescence and room temperature ferromagnetism. 

Bappaditya Pal and P.K. Giri (Department of Physics, Indian Institute of Technology Guwahati -781 039, 

India) giri@iitg.ernet.in, b.pal@iitg.ernet.in 


Transition metal doped ZnO is a promising candidate material for the field of spin-electronics, since 

theoretical studies have predicted it‟s Curie temperature (Tc) to be above room temperature. Doping studies 

have been mostly performed on thin film or powder sample of ZnO. Very few studies have attempted to 

doped ZnO nanoparticles with transition metals. 

76



We report on the occurrence of enhanced photoluminescence and room temperature ferromagnetism in Codoped 

ZnO nanoparticles (NPs). Doping is performed by ball milling of 3 wt% of Co mixed with ZnO 

nanopowders (commercial) for durations of 2-8 hrs. X-ray diffraction data and high resolution transmission 

electron microscopy (HRTEM) confirm the absence of metallic Co clusters or any other phase different from 

würtzite-type ZnO. The field dependence of magnetization (M–H curve) measured at room temperature 

exhibited the clear ferromagnetic characteristic with saturation magnetization (Ms) and coercive field (Hc) of 

, respectively. Post- 

-visible absorption 

spectra show red-shift in the absorption peaks in the Co doped ZnO NPs indicating incorporation of Co 

atoms in ZnO lattice. Room temperature photoluminescence studies show enhanced near-band-edge 

emission at 378 nm in the doped NPs as compared to the undoped ZnO NPs indicating negligible presence of 

defects in the doped ZnO crystals. This work demonstrates the feasibility of large scale production of 

ferromagnetic semiconductors that are potentially useful for building nanoscale spintronic devices. 


We have achieved Co doping of ZnO nanoparticles by planetary ball milling technique. Structural analysis 

confirm the absence of metallic Co clusters or any other phase different from würtzite-type ZnO. We 

observed clear room temperature ferromagnetism with saturation magnetization (Ms) and coercive field (Hc) 

of the order o 

systematically and it is concluded that defects do not play any significant role in the FM of CoZnO. We also 

observed enhanced PL emission in the Co doped ZnO NPs. 

12H20-12H40 

Study of Composition, Structure and Optical Properties of Nano-structured 

ZnS:Mn Thin Films Prepared by Chemical Deposition Method. 

Alireza Goudarzia, Reza Sahraeib ,Chang-Sik Hac,* (aDept.of Polymer Engineering, Golestan 

University,Gorgan,Iran.,bDept.of Chemistry, University of Ilam, Ilam, cPolymer Science and Engineering Pusan 

National University, Busan 609-735,Republic of Korea) csha@pusan.ac.kr 

1 – Introduction: 

Zinc sulfide is a semiconductor suitable for use as a host matrix for a wide variety of dopants on account of 

its wide energy band gap. The luminescent properties of this material doped with Mn have proven to be 

suitable for electroluminescence applications. Manganese is generally incorporated as Mn2+ ion in the 

substitutional sites of the ZnS lattice. ZnS:Mn films, however, have been usually prepared by expensive and 

difficult (strict) methods. Doping zinc sulfide with manganese is usually made by thermal diffusion of Mn 

salt at high temperature, such as, for example, spray pyrolysis method1,2. In this work, we report the 

preparation of Mn2+ doped ZnS thin films by chemical bath deposition (CBD) method at different 

temperatures and Mn2+ concentrations. The CBD method is simple, convenient and cost effective because it 

is normally carried out at atmospheric pressure (usually in air) and near ambient temperatures. It has the 

advantage of not requiring vacuum systems and is compatible with large area deposition. 


77


In this work, ZnS:Mn thin films were deposited on quartz, Si (polycrstal), and glass substrates using a CBD 

method in an aqueous solution containing ethylene diamine tetra acetic acid disodium salt (Na2EDTA) as the 

complexing agent for zinc ions and TAA as the sulfide source at different temperatures. ZnS: Mn thin films 

with thicknesses ranging from 60 to 450 nm were synthesized at various Mn2+/Zn2+ molar ratios ranging 

from 1 to 4. The effects of the process parameters on the properties of ZnS:Mn films were investigated. The 

films were characterized by energy dispersive X-ray spectrometer (EDX), inductively coupled plasma atomic 

emission spectroscopy (ICP-AES), secondary ion mass spectrometry (SIMS), X-ray diffractometer (XRD), 

high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy 

(FE-SEM), ultra violet –visible light (UV-Vis) spectroscopy, and photoluminescence (PL) spectroscopy. 


The results showed that the deposition time, deposition temperature, and Mn doping concentration can affect 

the composition, surface morphology, crystallinity, thickness, grain size, and hence the photoluminescence 

and transmission spectra of the films. The SIMS and Photoluminescence studies revealed the presence of two 

kinds of Mn in ZnS:Mn films that exhibit their own characteristic emissions. 

1)Hernández-Fenollosa, M. A., et al., Thin Solid Films 2008, 516, 1622. 

2)López, M. C.,et al., J. Crys. Grow. 2005, 285, 66. 

78

P R O G R A M THURSDAY, JULY 1 N A N O S E A 2 0 1 0 

Thursday, July 1 

Session 12 

Room Calendal 

III-V Semiconductors (Chairman: Mesli) 

9H00-9H40 

KAPON (EPFL SB IPEQ LPN, PH D3 425 (Bâtiment PH), Station 3CH-1015 Lausanne, Switzerland). 

Directed-Self-Ordering of Semiconductor Quantum Nanostructures Grown on 

Nonplanar. 

9H40-10H00 BRU-CHEVALLIER (1 INL Université de Lyon, CNRS UMR-5270, Ecole Centrale de Lyon, 69134, 

Ecully, France. 2 INL Université de Lyon, CNRS UMR-5270, INSA de Lyon –Bât Blaise Pascal, 69621 

Villeurbanne Cedex France. 3 LPN, CNRS UPR 20, route de Nozay, 91460 Marcoussis, France. 4 FOTON, CNRS 

6082, INSA, 20 avenue des buttes de Coesmes, 35708 Rennes Cedex 7). 

In(Ga)As quantum dots grown by Molecular Beam Epitaxy on Si substrates. 

10H00-10H20 

HAZDRA (1Department of Microelectronics, Faculty of Electrical Engineering, Czech Technical University in 

Prague, Technická 2, CZ-16627 Prague 6, Czech Republic, 2Institute of Physics of the AS CR, v. v. i., 

Cukrovarnická 10, 162 53 Prague 6, Czech Republic). 

Self-assembled InAs quantum dots embedded into GaAs with different strain 

reducing layers exhibiting strong photo- and electroluminescence in 1.3 and 1.55 μm 

bands. 

10H20-10H40 ILAHI ((1) Laboratoire de Micro-Optoélectronique et Nanostructures, Faculté des Sciences, Avenue de 

l‟environnement, 5019 Monastir, Tunisia. (2)Centre de Recherche en Nanofabrication et Nanocaractérisation 

(CRN2), Université de Sherbrooke, (Québec) Canada J1K 2R1. (3) Institut des Nanotechnologies de Lyon, UMR 

5270, Bat. F7, 36 avenues Guy de Collongue, 69134 Ecully Cedex, France). 

Temperature dependent photoluminescence properties of InAs/InP quantum sticks 

subjected to low energy phosphorous ion implantation and subsequent annealing. 

10H40-11H10 


79


Session 13 

Room Calendal 

Growth and Self Organisation (Chairman : Tersoff) 

11H10-11H30 AQUA (IM2NP, CNRS – Univ. Aix Marseille, Campus St. Jérôme, Case 142, 13397 Marseille CEDEX 20, 

France). 

Anisotropy driven interrupted coarsening of the Grinfeld instability. 

11H30-11H50 

COLIN (1) PHYMAT-CNRS UMR 6630, Université de Poitiers, BP 30179, 86962 Futuroscope Cedex, France; 

2) CINaM-CNRS, UPR 3118, Aix-Marseille Universit\'e, Campus de Luminy, Case 913, 13288 Marseille Cedex, 

France). 

Nanostructure instability induced by anisotropic epitaxial stresses. 

11H50-12H10 

BUSSMANN (CINaM-CNRS UPR 3118, Campus de Luminy, Case 913, 13288 Marseille Cedex 9, France). 

Dewetting of silicon-on-insulator thin films measured by Low Energy Electron 

Microscopy. 

12H10-12H30 PIERRE-LOUIS (1- la Doua, Bâtiment Léon Brillouin, 43 Boulevard du 11 Novembre 1918, F 69622 

Villeurbanne, France ; 2- Universidade Federal Fluminense,Avenida Litoranea s/n, 24210-340 Niteroi RJ, Brazil ; 3- 

Keio University, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama, Kanagawa, 223-8522 Japan). 

Dewetting of Solid films. 

12H30-13H00 

VVEDENSKY (CAH: Department of Applied Physics, Califonia Institute of Technology, Pasadena, CA 

91125, USA, DDV: The Blackett Laboratory, Imperial College London, London SW7 2AZ, UK). 

Coarse-Grained Theory of Growth on Patterned Substrates. 

13H00-17H00 


80


Session 14 

Room Calendal 

Island (Chairman: Ronda) 

17H00-17H30 

VENABLES (1) Physics, 2) Materials, Arizona State University, Tempe, Arizona, USA, 3) LCN-UCL, 

London, UK; 4) Lawrence Semiconductor, Tempe, Arizona, USA). 

Modeling Facet Nucleation and Growth of Hut Clusters on Ge/Si(001) 

17H30-17H50 COMBES (CNRS, CEMES (Centre d'Elaboration des Matériaux et d'Etudes Structurales), BP 94347, 29 rue J. 

Marvig, 31055 Toulouse,France - Université de Toulouse, UPS, 31055 Toulouse, France). 

Epitaxial growth on a dynamically patterned substrate: a theoretical study. 

17H50-18H10 

BREHM (1 Institute of Semiconductor Physics, Johannes Kepler University, Linz, Austria, 2 L-NESS and 

Materials Science Department, University of Milano-Bicocca, I-20125 Milano, Italy). 

Sorting thermodynamic and kinetic paths in the transition from 2D to 3D dot growth. 

18H10-18H30 PERSICHETTI (Department of Physics, University of Roma “Tor Vergata” - Via della Ricerca Scientifica, 1 

Roma, Italy). 

Formation and Localization of GeSi Quantum Dots on vicinal surfaces: a Scanning 

Tunneling Microscopy Characterization. 

18H30-18H50 

RICHARD ((a) Univ. Paul Cézanne, IM2NP, Marseille (France); (b) ID01/ESRF, Grenoble (France); (c) CEA 

Grenoble, INAC (France; (d) Univ. Complutense Madrid (Spain); (e) Univ. Zaragoza, ICMA (Spain); (f) Grenoble 

INP Minatec, LMGP (France); (g) Johannes Kepler Univ. Linz (Austria); (h) IFW Dresden (Germany)). 

In situ and ex situ x-ray studies of the growth of Ge islands on nominal and nanostructured 

Si(001) substrates. 

81


Thursday, July 1 

Session 15 

Room Port-Pin 

Opto-Electronic Properties (Chairman: Del Sole) 

9H00-9H40 

GONIAKOWSKI (Institut des Nanosciences de Paris, France). 

Polarity effects in ultra-thin oxide films. 

9H40-10H00 

PALUMMO ((a) ETSF, Fisica, Univ. Tor Vergata Via della Ricerca Scientifica I, Rome Italy, (b) ETSF, Ecole 

Polytecnique, CEA/CNRS Palaiseau France, (c) ETSF, Dpto. Fisica de Materials, Univ. del Pais Vasco, San 

Sebastian Spain). 

Optoelectronic properties of porphyrines oligomers: an ab-initio study. 

10H00-10H20 

SIMAO (ICMAB-CSIC., Campus de la UAB, 08193 Bellaterra, Barcelona, Spain). 

Self-assembly of Tetrathiafulvalene on Surfaces studying the Charge Transfer 

Phenomena. 

10H20-10H40 

BONOD (Institut Fresnel, Domaine Universitaire de Saint Jérôme, 13397 Marseille, France). 

Ligt absorption by nanostructured metals. 

10H40-11H00 KATAN (FOTON, INSA, CNRS, 20 avenue des buttes de Coësmes, CS70839, F-35708 RENNES Cedex 9, 

CPM, Unniversité Rennes 1, CNRS, campus de beaulieu, Case 1003, F-35042 RENNES Cedex). 

Photophysical properties of alternated pyridine-ethylenedioxythiophene oligomers 

investigated with TD-DFT: towards light triggered molecular springs 

11H00-11H30 


82


Session 16 

Room Port-Pin 

Nanostructured Substrates (Chairman: Venables) 

11H30-11H50 

NOGUERA (*Institut des Nanosciences de Paris, France. **Physique des matériaux, Poitiers). 

Structure of MgO nano-islands on metallic substrates: A semi-empirical, order N, 

Hartree-Fock simulation. 

11H50-12H10 

GOUGET-LAEMMEL (1Physique de la matière condensée, Ecole Polytechnique – CNRS, France, 

2Interdisciplinary Research Insitute (IRI), France). 

Amorphous silicon-carbon alloys for efficient sensing through localized surface 

plasmon and fluorescence detection. 

12H10-12H30 

KVEGLIS (1 Siberian Federal University, 2 East Kazakhstan State Technical University, 3 Kirensky Institute of 

Physics SB RAS). 

The Formation of Quantum Dots in Thin Nanostructured Films 

12H30-12H50 

DUCERE (1 CNRS ; LAAS ; 7 avenue du Colonel Roche, F-31077 Toulouse, France, 2 Université de Toulouse 

; UPS, INSA, INP, ISAE ; LAAS ; F-31077 Toulouse, France). 

Tail effect on trihydroxysilanes dimerization: a DFT study. 

12H50-17H00 


83


Session 17 

Room Port-Pin 

Metallic Nanoparticles (Chairman: Fiorani) 

17H00-17H30 

PETIT (Université Pierre et Marie Curie-Paris 6; CNRS UMR 7070, LM2N, 4 place Jussieu 75005 Paris, 

France). 

Metallic Nanocrystals and Nanoalloys obtained by soft chemistry: Growth process 

and self-organization into 2D and 3D super crystals 

17H30-17H50 

KNOBEN (Holst Centre/IMEC - High Tech Campus 31, 5656 AE Eindhoven, The Netherlands). 

The effect of ethanol vapor on metal-induced fluorescence enhancement. 

17H50-18H10 

THOMAZEAU ( a IFP-Lyon, Rond-point de l'échangeur de Solaize, BP 3 - 69360 Solaize - France; b 

Laboratoire de Chimie de la Matière Condensée de Paris, LCMCP, Collège de France, Bât. C-D, 11 place Marcelin 

Berthelot, 75231 Paris Cedex 05, France). 

Nanodesign of metallic catalysts : well defined metallic nanoparticles supported on 

alumina 

18H10-18H30 

TRABATTONI (University of Milano-Bicocca, Department of Materials Science, via Cozzi 53, I-20125, 

Milan). 

Self-assembly of gold nanoparticles on functional organic molecular crystals. 

84


Session Poster P3-P4 

AOUASSA 

Self-organisation of Si nanodroplets by dewetting of ultra-thin crystalline and 

amorphous SOI. 

mansour.aouassa@im2np.fr 

BENAMEUR 

Genotoxicity mechanism of CeO2 nanoparticles in human dermal fibroblasts. 

sylvia.pietri@univ-provence.fr 

BIRJEGA 

Mg-Al Layered Double Hydroxides and derived mixed oxides thin films grown by 

laser techniques. 

ruxandra.birjega@inflpr.ro 

BIRJEGA 

Morphological and microstructure features in ordered mesoporous aluminas. 

ruxandra.birjega@inflpr.ro 

BOYTSOVA 

Microstrain in YBCO-based nanocomposite thin films with self-assembly perovskite 

inclusions grown by MOCVD. 

boytsova@gmial.com 

BUYANOVA 

Free exciton dynamics in ZnO tetrapod structures. 

irb@ifm.liu.se 

CARCEL 

Photocatalytic degradation of methylorange using TiO2, WO3 and mix thin films 

under controlled pH and H2O2. 

carcel.adrian@unitbv.ro> 

CARCEL 

The heavy metals and dyes removal, the efficiency on fly ash and wood hash. 

visamro2000@yahoo.com 

CARJA 

Cellulose acetate/hydrotalcite – like anionic clay nanocomposites. 

carja@uaic.ro 

CARJA 

Ag/ZnLDH and Ag/MgLDH as nanostructured assemblies for antimicrobial coating. 

carja@uaic.ro 

DESPOTULI 

Nanoionic Supercapacitors for Future Deep-sub-voltage Nanoelectronics and 

Perspectives of Nanoelionic Devices. 

despot@ipmt-hpm.ac.ru 

85


DJEFFAL 

An explicit Continuous analytical model for Gate All Around (GAA) MOSFETs 

including the hot-carrier degradation effects. 

faycaldzdz@hotmail.com 

GADENNE 

Self-Assembled Monolayers of Various Conjugated Macrocycles Grafted on Silicon 

Oxide and Gold Surfaces. 

virginie.gadenne@im2np.fr 

GONCHAROV 

Transport properties of junctions and lattices via solvable models. 

Lev.goncharov@mail.ru 

GOUYE 

Solid Phase Epitaxy of Ultra-Highly Doped Silicon Layers. 

adrien.gouye@im2np.fr 

ILAHI 

Photomodulated reflectance and photoluminescence study of strain engineered 

InAs/(In)GaAs quantum dot. 

bouraoui.ilahi@fsm.rnu.tn 

INCERTI 

Nanostructured self-lubricating CrN-Ag films for tribo-mechanical applications. 

luca.incerti@unimore.it 

JOKIC 

The influence of silicon substitution on properties of spherical and whisker like 

hydroxyapatite particles. 

bjokic@tmf.bg.ac.rs 

KAMEI 

Self assembly of honeycomb TiO2 coatings by “tea-leaf extracts” as the dispersoids. 

KAMEI.Masayuki@nims.go.jp 

KAMIENIARZ 

Phenomenological modeling of the experimental molecular chromium-based rings. 

bgjk@amu.edu.pl 

KAMIENIARZ 

Application of the package SIESTA to a molecular chromium-based ring. 

bgjk@amu.edu.pl 

KUDLASH 

Nanosized inorganic particles prepared via interphase synthesis 

alexk11@tut.by 

LE THANH 

Enhanced Curie temperature in carbon-doped Mn5Ge3Cx films grown on Ge(111) 

by MBE. 

lethanh@cinam.univ-mrs.fr 

86


LEMINE 

Application of neural network technique to mechanical milling process for 

synthesizing ZnO. 

leminej@yahoo.com 

MAHAMDI 

ANN-based approach to study the ISFET sensors in PSPICE environment. 

ra_mahamdi@yahoo.fr 

MIU 

Gold nanoparticles embedded in polyelectrolytes multilayer for new hybrid 

nanosystems. 

mihaela.miu@imt.ro 

MIU 

Opto-electrical properties of nanoporous silicon impregnated with metallic cations. 

mihaela.miu@imt.ro 

NADAR 

Growth of silver nanoparticles inside mesoporous titania thin films for 

photochromism 

nathalie.destouches@univ-st-etienne.fr 

PATRONE 

Role of labile bonding in stochastic switching of molecular conductance studied by 

STM. 

lionel.patrone@im2np.fr 

PINGITORE 

The role of intrinsic and extrinsic impurities on cathodoluminescence from carbon 

nanotubes. 

marianna.barberio@fis.unical.it 

PISARRA 

Secondary Electron Emission from grapheme adsorbed on Ni(111) surfaces. 

riccardi@fis.unical.it 

SADJADI 

Preparation of nanosize core-shell ZnO /SiO2 structure for immobilization of the 

alkaline protease enzyme. 

msadjad@gmail.com 

SAHOO 

Magnetic anisotropy in Ni-Zn ferrite nanoparticles. 

balaram.sahoo@desy.de 

SIMAO 

Self assembly of tetrathifulvalene on surfaces studying the charge transfer 

phenomena. 

csimao@icmab.es 

TANEMURA 

Wavelength tunable random lasing in ZnO 3-D nanostructures. 

tanemura-sakae@jfcc.or.jp 

87


TEODORESCU 

TEM study of the TiO2 nantubes obtained by hydrothermal treatment 

teoval@infim.ro 

88

A B S T R A C T S THURSDAY, JULY 1 N A N O S E A 2 0 1 0 

Room Calendal 

9H00-9H40 

Directed-Self-Ordering of Semiconductor Quantum Nanostructures Grown on 

Nonplanar. 

Eli Kapon (EPFL SB IPEQ LPN, PH D3 425 (Bâtiment PH), Station 3CH-1015 Lausanne, Switzerland). 

Spontaneous nucleation and self-ordering of semiconductor quantum nanostructures such as quantum wires 

(QWRs) and quantum dots (QDs) has been extensively studied and employed in investigations of the 

properties and applications of these systems in electronics and photonics. Since the size, composition and 

environment of these nanostructures fundamentally determine their physical properties, the absence of 

structural control renders them of little use in deterministic quantum nanostructure systems. 

An alternative approach is that of directed-self-ordering, in which the nucleation and formation of the 

nanostructures can be tailored for specific designs. An example of such approach is epitaxial growth on 

patterned, nonplanar substrates. Here, a non-planar surface template serves to define the location where 

QWRs and QDs form. Such technique is particularly useful when the surface templates evolves in a selflimiting 

fashion. This is the case of metal-organic vapor phase epitaxy (MOVPE) on pre-patterned 

substrates, in which growth rate anisotropy and nano-capillarity play a fundamental role [1]. 

This approach yields high quality, site-controlled (In)GaAs/(Al)GaAs V-groove QWR and pyramidal QD 

systems. High-uniformity, regular arrays of these structures (e.g., pyramidal QDs with ~1meV 

inhomogeneous broadening) have been demonstrated [1,2]. The confining potential of these wires/dots can 

be controlled by thickness and /or composition adjustment, like in conventional quantum well structures. 

Capillarity-driven alloy segregation in the pyramidal structures provides the possibility of constructing novel 

QWR-QD assemblies (e.g., QD molecules) showing novel optical properties [3]. The high symmetry of the 

pyramidal QDs, grown on the (111)B substrates, yields unique excitonic features such as vanishing fine 

structure splitting, resulting in efficient emission of entangled photons [4]. The excellent site- and emission 

wavelength control facilitates integration with optical microcavities for applications in quantum information 

processing and ultra-low-threshold nano-lasers [5]. 

References: 

1. G. Biasil and E. Kapon, Phys. Rev. Lett. 81, (1998). 

2. M. Felici et al., Small 5, 938 (2009); A. Mohan et al., Small, 2010 (in print). 

3. Q. Zhou et al., Small 5, 329 (2009). 

4. A. Mohan et al., Nature Photonics, March 2010. 

5. P. Gallo et al., Appl. Phys. Lett. 92, 63101 (2008); K. Atlasov et al., Opt. Express 17,18178 (2009). 

89


9H40-10H00 

In(Ga)As quantum dots grown by Molecular Beam Epitaxy on Si substrates. 

A. EL AKRA1, H. DUMONT1, P. REGRENY1, D. PELLOUX-GERVAIS2, B. 

CANUT2, G. PATRIARCHE3, M. GENDRY1, J.M. JANCU4, J. EVEN4, C. BRU- 

CHEVALLIER2 (1 INL Université de Lyon, CNRS UMR-5270, Ecole Centrale de Lyon, 69134, Ecully, 

France. 2 INL Université de Lyon, CNRS UMR-5270, INSA de Lyon –Bât Blaise Pascal, 69621 Villeurbanne Cedex 

France. 3 LPN, CNRS UPR 20, route de Nozay, 91460 Marcoussis, France. 4 FOTON, CNRS 6082, INSA, 20 

avenue des buttes de Coesmes, 35708 Rennes Cedex 7). Catherine.Bru-Chevallier@insa-lyon.fr 


The aim of this study is to achieve homogeneous, high density and dislocation free In(Ga)As quantum dots 

(QDs) grown by molecular beam epitaxy (MBE) on silicon substrates. This work is part of a project which 

aims at overcoming the severe limitation suffered by silicon regarding its optoelectronic applications, 

especially efficient light emission device. For this study, one of the key points is to overcome the expected 

type II InAs/Si interface by inserting the In(Ga)As QDs inside a thin silicon layer deposited on a SOI 

substrate. Confinement effects of the Si/SiO2 quantum well are expected to heighten the indirect silicon 

bandgap and then give rise to a type I interface with the In(Ga)As QDs. In order to get light emission from 

such QDs, a key point is to avoid any dislocations or defects in the In(Ga)As QDs. 


The main factors responsible for the In(Ga)As QDs size, shape and structural quality are: the lattice 

mismatch between In(Ga)As and Si substrate, the surface energy of both In(Ga)As and Si, the interface 

energy between In(Ga)As and Si and the adatom mobility during the growth process. We investigated the dot 

size distribution and density at different V/III beam equivalent pressure (BEP) ratios and different growth 

temperatures. TEM images are used to study the structural quality of the QDs. Dislocation free In(Ga)As QD 

were successfully obtained. RBS-channeling analysis of such QDs on Si will also be presented. Optical 

properties and band alignment are modeled within the tight binding approximation and state of the art DFT 

calculations. 


Further works are going on concerning the capping of these In(Ga)As QD by a silicon epilayer in order to get 

efficient PL emission from these In(Ga)As QD elaborated on Si substrates. 

This work is supported by the ANR-pnano program (project “BIQUINIS”). 

90


10H00-10H20 

Self-assembled InAs quantum dots embedded into GaAs with different strain 

reducing layers exhibiting strong photo- and electroluminescence in 1.3 and 

1.55 μm bands. 

P. Hazdra1, J. Oswald2, V. Komarnitskyy1, K. Kuldová2, A. Hospodková2, E. 

Hulicius2 and J. Pangrác2 (1Department of Microelectronics, Faculty of Electrical Engineering, Czech 

Technical University in Prague, Technická 2, CZ-16627 Prague 6, Czech Republic, 2Institute of Physics of the AS 

CR, v. v. i., Cukrovarnická 10, 162 53 Prague 6, Czech Republic). hazdra@fel.cvut.cz 

Investigation of self-assembled InAs quantum dots (QD) in GaAs is motivated by the demand for highspeed, 

low cost, low pumping power and temperature stable lasers for 1.3 or 1.55 μm optical communication 

bands. Embedding of QDs in a functional structure can be optimized by covering them with a thin strain 

reducing layer (SRL) which modifies the QDs shape and composition, as well as composition of surrounding 

barriers, leading to changes of electronic structure and emission wavelength. 

In this paper, we report about self organized InAs QDs embedded in GaAs using low temperature grown 

InGaAs or GaAsSb SRLs. The structures were prepared on GaAs substrates by low pressure metalorganic 

vapour phase epitaxy (MOVPE). The RAS (Reflectance Anisotropy Spectroscopy) LayTec equipped 

AIXTRON 200 reactor and the Stranski–Krastanow growth mode at 490°C was used for sample preparation. 

TMIn, TMGa and AsH3 were used as precursors for samples with InxGa1-xAs SRLs; TEGa, TMIn, TBAs 

and TESb for structures with GaAs1-ySby SRLs. For QD formation, the growth was interrupted for 15 s 

after the formation of 2 ML of InAs. While RAS was used for in-situ growth monitoring, grown QD 

structures by were characterized using atomic force microscopy (AFM) and X-ray diffraction. Photo- (PL) 

and electroluminescence (EL) was used for monitoring of optical properties. Analysis of PL and AFM data 

was supported by numerical simulation of QD electron states. 

Results show that a proper In0.23Ga0.77As SRL narrows a broad PL spectrum of uncovered QDs (4 6 nm 

high InAs lenses) and causes a red shift of its maximum up to 1.55 µm. Analysis of measured data showed 

that this is affected both by the change of the barrier and by the increase of the height of the overgrown QDs. 

In the case of GaAsSb SRL, the red shift is smaller since the QD size is preserved but not increased. Higher 

Sb content increases the red shift due to gap alignment modification, however, at 19% of Sb in SRL, the 

QD/SRL heterojunction type changes from type I to type II and PL efficiency decreases due to smaller 

overlapping of electron and hole wave functions. EL characteristics of InAs QD structures successfully 

embedded in functional PiN diodes will be presented, as well. 

91


10H20-10H40 

Temperature dependent photoluminescence properties of InAs/InP quantum 

sticks subjected to low energy phosphorous ion implantation and subsequent 

annealing. 

M. H. Hadj Alouane, B. Ilahi* and H. Maaref, B. Salem#, V. Aimez, and D. Morris, 

A. Turala, P. Regreny, and M. Gendry ((1) Laboratoire de Micro-Optoélectronique et Nanostructures, 

Faculté des Sciences, Avenue de l‟environnement, 5019 Monastir, Tunisia. (2)Centre de Recherche en 

Nanofabrication et Nanocaractérisation (CRN2), Université de Sherbrooke, (Québec) Canada J1K 2R1. (3) Institut 

des Nanotechnologies de Lyon, UMR 5270, Bat. F7, 36 avenues Guy de Collongue, 69134 Ecully Cedex, France). 

bouraoui.ilahi@fsm.rnu.tn 


For monolithic integration of QD-based optoelectronic devices, selective post growth energy band gap 

tuning of QD structures is highly required. It can be ensured by spatial selective intermixing across the same 

sample surface. Among the existing intermixing techniques, low energy-ion-implantation and subsequent 

annealing is the most suitable process allowing: reproducibility, area selectivity and precise control of the 

defects depth and concentration. Extensive reports already exist on the effect of intermixing on the low 

temperature luminescence peak position, linewidth and integrated intensity. However, there are still some 

unknowns concerning the evolution of the temperature dependent photoluminescence properties as a 

function of the intermixing degree. The investigation and understanding of this phenomenon is important to 

assure efficient control of the device performance. 


In this work, the temperature dependent photoluminescence (PL) spectra was performed on InAs/InP 

quantum sticks QSs samples which were implanted with phosphorus ions at doses in the range of 1x 1011 – 

5x 1014cm-2 and subsequently annealed at 600°C for 120s to set off the intermixing. More details 

concerning the growth and implantation procedure can be found elswhere1. 

10 K PL measurements revealed a purely induced phosphorus-ion-implantation blue-shift as large as 275 

meV for an implantation dose of 5x1013 cm-2. Higher implantation doses results in saturation of the 

blueshift and a decrease of the integrated PL intensity. The FWHM is found to increase with increasing the 

ion implantation dose up 1012 cm-2. Higher implantation doses result in a narrowing of the PL linewidth. 

The broadening of the PL linewidth at lower doses can be explained by an inhomogeneous intermixing 

process which occurs when the density of vacancies is below the onset required for efficient QS 

intermixing2. 

No major modifications were observed in the temperature behavior of luminescence peak for the as-grown, 

only annealed sample and sample implanted at 1011 cm-2. For ion implantation doses in the intermediate 

range (1012 to 1013 cm-2), the emission energies exhibits a kink effect with a V shaped PL linewidth. As a 

consequence of the inhomogeneous intermixing enhanced QS‟s size and composition dispersion, for the 

latter dose‟s range, the temperature dependent PL is found to be dominated by carriers transfer between 

intermixed and non intermixed QSs having different confining potential depth. 

For higher implantation doses, QSs are uniformly intermixed which reduces carrier transfer. Accordingly, for 

implantation doses above 5x1013 cm-2, we have observed, a continuous increase of the PL linewidth with 

increasing temperature. Such a behavior has also been observed for the non-intermixed QSs samples and 

correlated with the electron-phonon scattering. However, the PL emission energies are found to deviate from 

Varshni empirical law at lower temperature. The observed behavior can be interpreted in terms of carriers 

92


localization at the interface roughness induced by the relatively high defect density and consequent 

possibility of QSs dissolution to a quasi-2D layer. 


Different temperature behaviors of the photoluminescence have been observed depending on the ionimplantation 

induced intermixing degree (doses range). For low implantation doses, responsible for an 

inhomogeneous intermixing the PL emission energies and linewidth are found to be governed by the carriers 

transfer between different QSs having different confining potential depth. However, highly intermixed QSs 

PL emission energy are found to be dominated by carriers localizations suggesting their dissolution to a 

quasi-2D layer 

1Salem et al Appl. Phys. Lett. 87, (2005) 241115 

2Zaaboub et al Nanotechnology 19, 285715 (2008) 

11H10-11H30 

Anisotropy driven interrupted coarsening of the Grinfeld instability. 

Jean-Noël Aqua, Thomas Frisch (IM2NP, CNRS – Univ. Aix Marseille, Campus St. Jérôme, Case 142, 

13397 Marseille CEDEX 20, France). jean-noel.aqua@centrale-marseille.fr 

93


94


95


11H30-11H50 

Nanostructure instability induced by anisotropic epitaxial stresses. 

Jérôme Colin, Jean Grilhé, Pierre Müller (1) PHYMAT-CNRS UMR 6630, Université de Poitiers, 

BP 30179, 86962 Futuroscope Cedex, France; 2) CINaM-CNRS, UPR 3118, Aix-Marseille Universit\'e, Campus de 

Luminy, Case 913, 13288 Marseille Cedex, France). jerome.colin@univ-poitiers.fr, jean.grilhe@univ-poitiers.fr, 

muller@cinam.univ-mrs.fr 


The morphological evolution of an initially straight stripe lying on a semi-infinite substrate is theoretically 

studied in the linear regime when the mass transport mechanism is the diffusion of ad-atoms along stripe 

edges and when the heteroepitaxy between the line and the substrate is taken to be anisotropic. 


In this work, one focuses on stress-driven instabilities of a straigth line epitaxially stressed on a semi-infinite 

substrate which can model monaoatomic stripes but also higher structures (but still at the nanoscale). The 

linear stability of an epitaxially stressed stripe of infinite length has been investigated when the heteroepitaxy 

between the stripe and the substrate is anisotropic. The effects of stress on the morphological evolution of the 

stripe by edge diffusion have been modelled within the framework of force monopole approximation and 

linear elasticity. The possibility of formation of pinched or serpentine-like shapes under the action of the 

biaxial stresses is discussed. 


The main result of this study is that anisotropic heteroepitaxial stresses between a stripe and its substrate 

strongly modify the morphological evolution of the stripe in its linear regime of evolution. Although a 

serpentine-like stripe develops when the epitaxial stresses is isotropic, a pinched shape preferentially 

emerges in the anisotropic case for selected components of stress. 

11H50-12H10 

Dewetting of silicon-on-insulator thin films measured by Low Energy Electron 

Microscopy. 

E. Bussmann , F. Leroy , F. Cheynis, P. Müller (CINaM-CNRS UPR 3118, Campus de Luminy, 

Case 913, 13288 Marseille Cedex 9, France). 


Silicon-on-inslulator (SOI) substrates are promising templates for next generation microelectronic devices 

such as single electron transistors [1,2] as well as field effect transistors with high-speed operation and low 

power consumption. Active single-crystalline layers in the sub-10nm range will be required in the near future 

[3]. However, SOI is unstable when annealed at high temperature (900°C). The SOI film dewets resulting in 

agglomerated nanocrystals [4-7], or nanowires [8]. The solid dewetting of SOI thin films represents both a 

critical process limitation for the fabrication of advanced devices as well as an open question in basic 

physics. 

96



Using low-energy electron microscopy (LEEM) and Grazing Incidence Small Angle X-ray Scattering 

(GISAXS), we have studied the evolution of the morphology and structure of dewetted thin-films from the 

nucleation of voids/holes until the growth of isolated Si nanocrystals. Depending on the surface preparation 

cleanness we find different dewetted morphologies [9]. For cleaned samples (see Fig. 1a) the dewetted areas 

are square-shaped holes with -oriented sides. Inside the holes, fingers form aligned in well-defined 

crystallographic directions , and . The fingers then break into Si aggregates. As shown 

by GISAXS (see Fig. 1b) and surface X-ray diffraction the Si nanocrystals keep the initial crystallographic 

orientation of the film. It is noteworthy that the dewetting of the layer occurs on an amorphous material 

(SiO2) showing that the crystallographic orientation of the top Si layer is a key parameter. 

We have quantitatively characterized the shape evolution, size, and ordering of the Si nanocrystals at 

different stages of the dewetting process, and as function of film thickness and temperature. We find that the 

activation barrier of the dewetting is dependent on the thickness of the SOI. We measure the dewetting 

kinetics using LEEM darkfield 

imaging. This technique reveals 

contrast between adjacent terraces 

by selecting a (2×1) 

reconstruction diffraction spot 

(Fig.2). We have measured during 

dewetting the mass transfer at the 

atomic level measuring the atomic 

step motion close to the edge of 

the hole, as well as the nucleation 

of new layers at the top of the 

(001) facet of the rim. These 

results are compared with 

theoretical models proposed in the 

literature [4,10,11]. 

Fig. 1 : (a) LEEM image of a dewetted SOI(001) thin film (20 nm) annealed at 850°C 

(10 min). Field of view 25 μm. (b) GISAXS image with a X-ray beam aligned along 

direction. Extended {113} and {111} facets are measured on the Si nanocrystals. 


Fig. 2 LEED/LEEM of dewetting of 22 nm-thick SOI films prepared by (T = 910 °C, FOV 25 µm, E = 7.8 eV ). 

Solid state dewetting of silicon-on-insulator templates have been studied in real time and in situ. The 

combination of real space imaging by LEEM and reciprocal space characterization by GISAXS has provided 

a detailed description of the process and a unique way to extract the key mechanisms involved in solid 

97


dewetting. We will show that a more complete theory is needed to understand all the aspects of the dewetting 

of Si on SiO2. 

Support by ANR PNANO (ANR 08-Nano-036) is gratefully acknowledged 

[1] P. Zhang et al., Nature 439 (9) 703 (2006). 

[2] Lundstrom, W. Schoenfeld, H. Lee, and P. M. Petroff, Science 286, 2312 (1999). 

[3] M. Leong, B. Doris, J. Kedzierski, K. Rim, M. Yang, Science 306, 2057 (2004) 

[4] D. T. Danielson et al. J. Appl. Phys. 100, 83507 (2006). 

[5] R. Nuryadi, et al., J. Vac. Sci. Technol. B, 20(1), 167 (2002). 

[6] B. Yang et al., Phys. Rev. B 72, 135413 (2005). 

[7] E. Dornel et al. , Phys. Rev. B 73, 115427 (2006). 

[8] Z.A. Burhanudin et al. Appl. Phys. Lett. 87, 121905 (2005) 

[9] E. Bussmann, F. Cheynis, F. Leroy, P. Müller, submitted 

[10] E. Jiran and C. V. Thompson Thin Solid Films, 208 23-28 ( 1992). 

[11] D.J. Srolovitz, S.A. Safran, J. Appl. Phys, 60, 255 (1986). 

12H10-12H30 

Dewetting of Solid films. 

O. Pierre-Louis(1), A. Chame(2), Y. Saito(3), M. Dufay(1) (1- la Doua, Bâtiment Léon 

Brillouin, 43 Boulevard du 11 Novembre 1918, F 69622 Villeurbanne, France ; 2- Universidade Federal 

Fluminense,Avenida Litoranea s/n, 24210-340 Niteroi RJ, Brazil ; 3- Keio University, 3-14-1, Hiyoshi, Kohoku-ku, 

Yokohama, Kanagawa, 223-8522 Japan). 


Solid films with sub-micron thicknesses may break-up into islands to lower their energy. Such a "dewetting" 

process was observed in many experimental systems . Up to now, the theoretical analysis of solid-film 

dewetting has been based on the Mullins continuum model for surface diffusion. This approach predicts the 

formation of a smooth dewetting rim at the edge of the film, with scaling laws for the increase of the radius 

of a hole $\sim t^{1/4}$[Srolovitz et al 1986], and for the position of straight fronts $\sim t^{2/5}$[Wong et 

al 2000]. However, the presence of facets, the evolution of which is controlled by 2D nucleation, leads to 

novel phenomena which cannot be accounted for within the frame of the Mullins model. Examples include 

the relaxation of nano-crystals[Combe et al 2000, Mullins et al 2000], the drift of islands on vicinal 

substrates[Ling et al 2004], layer-by-layer dewetting of ice islands[Thurmer et al 2008], or the formation of 

labyrinthine patterns of bilayer islands during the dewetting of a monolayer[1]. 


We use the Solid on Solid KMC model of Ref.[1]. On a square lattice with lattice unit $a$ and periodic 

boundary conditions, the local height is $z\geq 0$. The substrate surface, at $z=0$, is flat and frozen. 

Epilayer atoms hop to nearest neighbor sites with rates $\nu_0\,{\rm e}^{-E/T}$, where $\nu_0$ is an 

attempt frequency, and $T$ is the temperature (in units with $k_B=1$). The hopping barrier is $E=nJ- 

\delta_{z,1}E_S$, where $n$ is the number of in-plane nearest neighbors, $J$ is the bond energy, $\delta$ is 

the Kronecker symbol, and $E_S$ is the adsorbate-substrate excess energy. Our energy unit is $J$, so that 

$J=1$. When $E_S\gg1$, the energy is minimized by creating high islands\cite{PierreLouis2007}. When 

$E_S\rightarrow 0$ the epilayer spreads on the substrate. We choose $0.3


based on 2D nucleation theory and diffusion-limited dynamics. When dewetting is heterogeneous, i.e. 

dewetting is initiated at pre-existing holes, or at the film edge,two regimes are obtained. 

A regime with a facetted multi-layer rim, where the front position scales as $t^{1/2}$, and a layer-by-layer 

dewetting regime where a monolayer islandnucleated far from the dewetting front invades the whole film. In 

contrast, during homogeneous dewetting, where holes arise from fluctuations in a perfect and clean system, 

multi-layer rims always form. 


Ultra-thin crytalline solid films are found to dewet with a facetted rim. In the case of heterogeneous 

dewetting initiated from a linear trench or from periodically arranged holes, the dewetted area expands 

either with a facetted multi-layer rim or in a layer by layer fashion. In the case of homogeneous dewetting, 

holes are accompanied with multi-layer rims and the uncoverage increases as a power law of time. Results of 

kinetic Monte Carlo simulations are elucidated within the frame of nucleation theory and surface diffusion 

limited dynamics. 

[1] Dewetting of a Solid Monolayer O. Pierre-Louis, Anna Chame, and Yukio Saito, Phys. Rev. Lett. 99, 136101 (2007). 

[2] Dewetting of Ultrathin Solid Films O. Pierre-Louis, A. Chame, and Y. Saito, Phys. Rev. Lett. 103, 195501 (2009). 

[3] Atomic step motion during the dewetting of ultra-thin filmsO. Pierre-Louis, A. Chame, M. Dufay, preprint (2010). 

12H30-13H00 

Coarse-Grained Theory of Growth on Patterned Substrates. 

C. A. Haselwandter and D. D. Vvedensky (CAH: Department of Applied Physics, Califonia Institute 

of Technology, Pasadena, CA 91125, USA, DDV: The Blackett Laboratory, Imperial College London, London SW7 

2AZ, UK). cah77@caltech.edu, d.vvedensky@imperial.ac.uk. 


We present a stochastic continuum theory of the formation of surface nanostructures in several experimental 

settings. The first step of our methodology is the systematic transformation of a lattice model for a particular 

system into a stochastic continuum equation of motion. With these regularized equations as initial 

conditions, renormalization group (RG) equations are formulated for the changes in the model coefficients 

under coarse graining. The solutions of the RG equations yield trajectories that describe the original model 

over a hierarchy of scales, ranging from transient regimes, which are of primary experimental interest, prior 

to the crossover to the asymptotically stable fixed point. Thus, our method yields continuum equations that 

describe atomistic growth models over expanding length and time scales, but retain a direct connection to the 

underlying atomistic transition rules. 


Our interest here is in the transient regime for several experimental scenarios, where the growth conditions 

play a central role in determining the form of the governing equation. We first briefly consider the regimes 

defined by the relative magnitudes of the diffusion and deposition noises. If diffusion noise dominates, then 

the early stages of growth are described by the Mullins-Herring (MH) equation with a conserved noise. This 

is the classical regime of molecular-beam epitaxy (MBE). If the diffusion and deposition noises are of 

comparable magnitude, the transient equation is the MH equation, but with nonconserved noise. This 

behavior has been observed in a recent report of Al on silicone oil surfaces. Finally, the regime where 

99


deposition noise dominates deposition noise has been observed in computer simulations, but does not appear 

to have any experimental relevance. 

For an initially flat surface, the Villain-Lai-Das Sarma (VLDS) equation with nonconserved noise is obtained 

for all models with random deposition and nearest-neighbor hopping. This equation is not observed in any 

transient regime for typical MBE conditions. If, however, the initial surface is corrugated, the relative 

magnitudes of terms in the equation of motion can be altered to the point where the VLDS equation does 

indeed describe transient growth, albeit with conserved noise. This is consistent with the analysis of growth 

on patterned surfaces reported by the Maryland group. We will discuss the effect of various types of patterns 

on the governing growth equations and their experimental consequences. 


We have shown how our previously developed methodology for deriving regularized stochastic continuum 

equations can account for much of the transient behavior seen in deposition/diffusion systems. On such 

surfaces, under typical conditions, the governing equations are found to be linear. The extent to which this 

can be extended to the submonolayer regime is currently being investigated. We have seen that the 

patterning of a substrate can pre-empt the behavior seen on initially flat substrates. The application of RG 

methods to see the complete evolution of such systems remains to be carried out. But already the systematic 

derivation of growth equations for patterned substrates represents a substantial advance for these important 

systems. 

17H00-17H30 

Modeling Facet Nucleation and Growth of Hut Clusters on Ge/Si(001). 

J. A. Venables1,3, D.R. Bowler3, M.R. McKay2,4 and J. Drucker1,2 (1) Physics, 2) 

Materials, Arizona State University, Tempe, Arizona, USA, 3) LCN-UCL, London, UK; 4) Lawrence 

Semiconductor, Tempe, Arizona, USA). 

Recent STM observations of homogenous distributions of pyramid and hut clusters on Ge/Si(001) have 

shown that these clusters grow extremely slowly during annealing at intermediate temperatures, T ~ 450 oC, 

when there is a super-saturation of mobile ad-particles above and within the wetting layer. Data has been 

obtained on the absolute length of the clusters as a function of time L(t), and thereby the evolution of the 

growth rate, over periods of order 100 hours [1]. We model this slow growth as a layer by layer (2D) facet 

nucleation and growth problem, in the presence of strain-induced energies both on and around the facets. 

All of these energies can markedly influence the nucleation rate of new facets. First, they justify the 

observation that facet nucleation occurs from the apex of the hut, as has been observed in several other 

studies [2, 3]. Second, they indicate a substantial slowing down of the nucleation rate, by many orders of 

magnitude, relative to the case when such energies are not present. Finally the need to undo the stable 

reconstruction on the {105} facets as each new layer is formed contributes an extra energy of order 0.5 eV 

[4] to the energy of the critical nucleus. 

Inclusion of these effects, with experimental values of the Ge diffusion coefficient, provides a quantitative fit 

to the L(t) data, and sets bounds on step and facet energies appropriate to hut clusters. Such energies are 

increasingly amenable to ab-initio calculation on reconstructed hut clusters to compare with experiment [5]. 

1. M.R. McKay, J.A. Venables and J. Drucker, Phys. Rev. Lett. 101, 216104 (2008); Solid State Comm. 149, 1403-1409 (2009) 

2. F. Montalenti et al., Phys. Rev. Lett., 93, 216102 (2004) 

100


3. S. Cereda, F. Montalenti and L. Miglio, Surface Sci. 591, 23-31 (2005) 

4. S. Cereda and F. Montalenti, Phys. Rev B 75, 195321 (2007) 

5. T. Miyazaki, D.R. Bowler, M.J. Gillan and T. Ohno, J. Phys. Soc. Japan 77, 123706 (2008); D.R. Bowler and T. Miyazaki, J. Phys. Condensed 

Matter (2009) in press, arXiv:0911.3584v1 [cond-mat.mtrl-sci] 

17H30-17H50 

Epitaxial growth on a dynamically patterned substrate: a theoretical study. 

C. Taillan, N. Combe, J. Morillo (CNRS, CEMES (Centre d'Elaboration des Matériaux et d'Etudes 

Structurales), BP 94347, 29 rue J. Marvig, 31055 Toulouse,France - Université de Toulouse, UPS, 31055 Toulouse, 

France). 

Experimentally, the epitaxial growth consists in a low energy deposition of atoms or molecules on a substrate 

and is generally used to create nanostructures (for instance quantum wells, wires or dots for semi-conductors 

or magnetic nanoparticles for metals...) that can be organized using their self- assembling properties. 

Unfortunately, the control of the spatial or size distribution of these structures remains indirect and difficult: 

for instance, experimentalists take advantages of the elastic properties of materials (Stranski-Krastanov 

growth mode, use of buried dislocations network ... etc). 

Our study aims to explore an alternative approach that could potentially improve this control. We study the 

diffusion of adatoms on a substrate submitted to a standing surface acoustic wave. 

The standing surface acoustic wave induces an effective potential for diffusing atoms and thus dynamically 

patterns the substrate. Minima of this potential form preferential sites for atomic diffusion and thus for 

island nucleation. Our study both implies molecular dynamic simulations of adatoms diffusion on 

crystalline surface, and analytical calculations using a Langevin approach. Using this last approach, we 

derive the expression of the effective potential under few hypothesis, and analyze the stability of its minima 

in the general case. The relation between numerical simulations and analytical calculations is given and 

reveals the coherence between both approaches results. 

The standing surface acoustic wave thus affects the adatoms diffusion on the substrate by creating 

preferential sites of nanostructures nucleation. The use of these waves would potentially allow a precise 

control of the spatial distribution of the nanostructures during the epitaxial growth 

17H50-18H10 

Sorting thermodynamic and kinetic paths in the transition from 2D to 3D dot 

growth 

M Brehm1, M Grydlik1, T Fromherz1, G Vastola2, F Montalenti2, L Miglio2, F 

Schäffler1 and G Bauer1 (1 Institute of Semiconductor Physics, Johannes Kepler University, Linz, Austria, 

2 L-NESS and Materials Science Department, University of Milano-Bicocca, I-20125 Milano, Italy). 

moritz.brehm@jku.at 

1 – The well established sequence of appearance of SiGe dots (from mounds to superdomes) grown in the 

Stranski-Krastanow growth mode on planar Si(001) substrates with increasing Ge deposition was 

straightforwardly understood in terms of increasing aspect ratio, providing a larger volumetric strain 

relaxation. The thermodynamic stability of the island types is still a matter of discussion. 

101


2 – Here we present clear experimental evidence for the formation of larger domes prior to smaller pyramids 

at growth temperatures (Tg) smaller than 675°C and for an "overcritical" behavior of the wetting layer 

(WL).These findings allow us to sort out thermodynamic and kinetic paths in the early stages of quantum dot 

formation. The results are obtained from systematic investigations of atomic force microscopy (AFM) and 

photoluminescence (PL) on samples grown by molecular beam epitaxy. By implementing a Ge gradient over 

4” wafers we achieved an extremely high deposition resolution of 0.025 monolayers (ML). At Tg =700°C we 

observe dome formation at Θ = 4.2 ML, while pyramids appear later, i.e. at Θ > 4.38 ML. The dome 

formation is initiated by a Ge transfer of 1 ML from the WL to the islands, as determined from the abrupt 

shift of the WL PL at the onset of the island PL. At Tg = 625°C the common dot formation sequence is 

observed. Mounds and small pyramids form already at about 2 ML followed by the nucleation of domes at 

4.9 ML. In order to understand whether the domes are actually stable prior to pyramids, accurate density 

functional theory calculations of surface energies and finite element method simulations of the elastic 

energies were performed, taking particular care in determining the total energy variations in the first few 

MLs of the WL. By a morphological phase diagram we both confirmed the early stability of the Ge-rich 

domes and the depletion of the WL at their onset, also addressing the appearance first of pyramids at 625°C 

to be a kinetic effect, leading to metastable islands. 

3 – An experimental proof for this prediction is obtained from extensive annealing experiments. After 

annealing at 700°C pyramids grown with Θ < 3.2 ML at 625°C form back to a completely flat WL, while for 

Θ > 3.2 ML domes are formed. Thus, we conclude that the critical WL thickness (tc) for stable island 

nucleation is about 3.2 ML. At the same tc domes are formed if we anneal an overcritical WL grown at 

700°C. Finally, we would especially like to highlight the strong similarities between dot formation in SiGe 

and III/V systems. 

18H10-18H30 

Formation and Localization of GeSi Quantum Dots on vicinal surfaces: a 

Scanning Tunneling Microscopy Characterization. 

L. PERSICHETTI, A. SGARLATA, M. FANFONI, A. BALZAROTTI (Department of 

Physics, University of Roma “Tor Vergata” - Via della Ricerca Scientifica, 1 Roma, Italy). 

persichetti@roma2.infn.it 


Due to the potential applications in novel nanostructured devices, the Stranski-Krastanov growth of ordered 

self-assembled islands in strained heteroepitaxial systems is a topic attracting ever-increasing interest. 

A natural model system is Ge on vicinal Si(001), which allows us to tune both the energetic and the kinetic 

factors governing the growth of individual nanostructures by changing the substrate miscut [1]. 


A complete description of Ge growth and ordering processes on vicinal Si(001) surfaces in the angular 

miscut range 0°-8° is presented. The key role of substrate vicinality is clarified from the very early stages of 

Ge deposition up to the nucleation of 3D islands [2]. By a systematic scanning tunnelling microscopy 

investigation we are able to explain the competition between step-flow growth and 2D nucleation and the 

progressive elongation of the 3D islands along the miscut direction [110]. 

102


In addition, we have systematically measured the spatial distribution of Ge islands as a function of the 

substrate vicinality, developing proper tools for the analysis of experimental data, successfully applied to the 

study of in-plane interactions among nanostructures [3]. 


In conclusion, we have reported a complete picture which provides new insights into the microscopic growth 

mechanisms on vicinal surfaces. 

Moreover, we demonstrate that substrate misorientation strongly affects island distribution by modulating 

both the diffusion and the local strain fields, which are both responsible for the short-range ordering. 

We support our results by modelling elastic relaxation for different shapes and arrangements of islands with 

finite element calculations. 

[1] M. Bernardi, A. Sgarlata, M. Fanfoni, L. Persichetti, N. Motta, A. Balzarotti, Superlattices and Microstructures 46, 318 (2009). 

[2] L. Persichetti, A. Sgarlata, M. Fanfoni, and A. Balzarotti, Physical Review Letters (in press). 

[3] L. Persichetti, A. Sgarlata, M. Fanfoni, and A. Balzarotti, (submitted). 

18H30-18H50 

In situ and ex situ x-ray studies of the growth of Ge islands on nominal and 

nano-structured Si(001) substrates. 

M.-I. Richard (a), T.U. Schülli (b), G. Renaud (c), N.A. Katcho (d), M.G. Proietti 

(e), H. Renevier (f), V. Favre-Nicolin (c), Z. Zhong (g), G. Chen (g), J.J. Zhang (g), 

M. Stoffel (h), O. Schmidt (h) and G. Bauer (g). ((a) Univ. Paul Cézanne, IM2NP, Marseille 

(France); (b) ID01/ESRF, Grenoble (France); (c) CEA Grenoble, INAC (France; (d) Univ. Complutense Madrid 

(Spain); (e) Univ. Zaragoza, ICMA (Spain); (f) Grenoble INP Minatec, LMGP (France); (g) Johannes Kepler Univ. 

Linz (Austria); (h) IFW Dresden (Germany)). 


The knowledge of strain, chemical composition, interface quality, atomic intermixing and ordering, is of 

great importance to understand the growth mechanism as well as the electronic and optical properties of 

hetero and nanostructures [1]. X-ray techniques have been used to address such a general issue in the case of 

the molecular beam epitaxy growth of Ge islands on nominal and nano-structured Si(001) substrates. 


The kinetics of the Ge/Si island growth and of their shape transitions is still not completely understood. This 

calls for in situ studies to understand and investigate the whole dynamic growth process. On BM32 at the 

ESRF in Grenoble, we have developed in situ x-ray scattering methods giving access to the evolution of size, 

shape, faceting, strain relaxation and intermixing during the growth. The combination of Grazing Incidence 

Small Angle X-ray Scattering (GISAXS) [2], X-ray Diffraction (GIXD) and Anomalous Scattering using the 

MAD (Multiwavelength Anomalous Diffraction) [3] method, all performed in situ, during growth in an Ultra 

High Vacuum chamber, allowed for the characterization of the Ge nano-islands regarding their shape and 

organization (GISAXS) as well as their strain and composition. This made possible to track the facet size 

evolution for growing Ge superdomes [4] on nominal Si(001) surfaces using a low growth rate, as well as to 

determine the material transport from the wetting layer during the transition form two dimensional to island 

growth [5]. 

103


To access to the Ge content inside the nano-islands, the MAD technique was combined ex situ with grazingincidence 

Diffraction Anomalous Fine Structure (DAFS) spectroscopy at beamline BM02, ESRF. DAFS 

gives information on the local environment of the Ge atoms (chemical sensitivity) located in an iso-strain 

volume selected by diffraction (spatial selectivity). This unique combination, together with recent atomistic 

simulations based on molecular dynamics (MD), has turned out to be a powerful approach to disentangle 

strain and composition (even in the case of sharp island/substrate interfaces [6,7]), to detect atomic ordering 

inside SiGe nano-islands and to quantify experimental spatial resolution issues. We will report recent results 

obtained on capped SiGe pyramids, free standing and capped domes. For small capped pyramids, DAFS is 

the unique non destructive method that allows to recover the actual Ge content and in-plane and out-of-plane 

strain. 

A challenge for the development of nano-electronics is also to elaborate semiconductor quantum dots that are 

homogeneous in shape, size, strain and composition, thus resulting in well-defined electronic and optical 

properties. Recently the growth of highly monodisperse Ge islands on prepatterned Si substrates has been 

obtained by a combination of lithography and self-assembly techniques [8]. To compare elastic relaxation 

and Si-Ge distribution in epitaxial islands grown on both pit-patterned and flat Si(001) substrates, ex situ 

studies were performed [9]. Anomalous x-ray diffraction yields that nucleation in the pits provides a higher 

relaxation. Using an innovative, model-free fitting procedure based on self-consistent solutions of the elastic 

problem, we provide real-space compositional and elastic-energy maps. Islands grown on flat substrates 

exhibit stronger composition gradients and do not show a monotonic decrease of elastic energy with height. 

Both phenomena are explained using both thermodynamic and kinetic arguments. 


The combination of the GISAXS, GIXD, MAD and DAFS techniques provides detailed results on the 

evolution of the shape, composition and the strain of Ge islands during the whole growth process. It is 

demonstrated to be a useful, destruction-free tool to understand and control the self-organized growth of 

nanostructures. 

[1] J. Stangl et al, Rev. Mod. Phys. 76, 725 (2004). 

[2] G. Renaud et al, Science 300, 1416 (2003). 

[3] A. Létoublon, V. Favre-Nicolin, H. Renevier et al, Phys. Rev. Lett. 92, 186101 (2004). 

[4] M.-I. Richard, T.U. Schülli, G. Renaud et al, Phys. Rev. B. 80, 045313 (2009) 

[5] T.U. Schülli, M.-I. Richard et al, Appl. Phys. Lett. 89, 143114 (2006). 

[6] M.-I. Richard, N.A. Katcho et al, Eur. Phys. J. Special Topics 167, 3 (2009). 

[7] N.A. Katcho, M.I. Richard et al, Journal of Physics: Conference Series 190, 012129 (2009). 

[8] Z. Zhong and G. Bauer, Appl. Phys. Lett. 84, 1922 (2004). 

[9]T.U. Schülli, G. Vastola, M.-I. Richard et al, Phys. Rev. Lett. 102, 025502 (2009). 

104


Room Port-Pin 

9H00-9H40 

Polarity effects in ultra-thin oxide films. 

Jacek Goniakowski and Claudine Noguera (Institut des Nanosciences de Paris, France). 

Jacek.Goniakowski @insp.jussieu.fr, Claudine.Noguera @insp.jussieu.fr 

Polar surfaces of extended objects present an electrostatic instability and require substantial modifications of 

their characteristics in order to become stable. Surface processes related to polarity compensation have been 

extensively studied in the last years and are seen as a potential tool for tuning surface properties [1]. 

With the reduction of the object sizes, as in the case of ultra-thin films, polarity effects gain an additional 

dimension and result in specific, thickness-dependent film properties. On one hand, for the thinnest films, the 

electrostatic instability may not occur at all. We have predicted that such films may sustain a considerable 

dipole moment and thus, contrary to extended systems, may exist in an uncompensated polar state [2]. On 

the other hand, at low thickness, polarity effects may extend beyond the surface region. We have predicted 

that they may lead to a structural transformation of the entire film, resulting in novel structures, different 

from those observed in thicker samples [3]. Additionally, we have shown that the energetic cost of polarity 

compensation may be substantially lowered by non-stoichiometry [4]. Oxide ultra-thin films are often 

synthesized on metal substrates. As result, their polarity characteristics are further modified by the covalent 

and electrostatic couplings which exist at the interface. They induce an interfacial charge transfer and 

electrostatic forces, responsible for a non-vanishing polarisation (rumpling) in the oxide film [5]. When 

species (molecules or metal atoms) are adsorbed on such ultra-thin films, two qualitatively different 

adsorption modes may take place, associated to a local polaronic-like distortion of the film (modification of 

rumpling) [6]. Contrary to the macroscopic dipole compensation characteristic of polar surfaces, the 

compensation of electrostatic dipoles which takes place at metal-supported oxide films is only partial and 

occurs along both polar and nonpolar orientations. 

We will exemplify several of these effects, which suggest that an adequate choice of the oxide/substrate 

electronic characteristics may be used to tailor surface structural characteristics and thus to tune the 

electronic and reactivity properties of such supports. 

1. J. Goniakowski, F. Finocchi and C. Noguera, Rep. Prog. Phys. 71, 016501 (2008). 

2. J. Goniakowski, C. Noguera and L. Giordano, Phys. Rev. Lett. 98, 205701 (2007). 

3. J. Goniakowski, C. Noguera and L. Giordano, Phys. Rev. Lett. 93, 215702 (2004). 

4. C. Noguera and J. Goniakowski, J. Phys.: Condens. Matt. 20, 264003 (2008). 

5. J. Goniakowski and C. Noguera, Phys. Rev. B 79, 155433 (2009). 

6. J. Goniakowski, C. Noguera, L. Giordano, and G. Pacchioni, Phys. Rev. B 80, 125403 (2009). 

105


9H40-10H00 

Optoelectronic properties of porphyrines oligomers: an ab-initio study. 

M.Palummo (a), C. Hogan (a), F. Sottile (b), A.Rubio(c) ((a) ETSF, Fisica, Univ. Tor Vergata 

Via della Ricerca Scientifica I, Rome Italy, (b) ETSF, Ecole Polytecnique, CEA/CNRS Palaiseau France, (c) ETSF, 

Dpto. Fisica de Materials, Univ. del Pais Vasco, San Sebastian Spain).maurizia.palummo@roma2.infn.it, 

conor.hogan@roma2.infn.it, francesco.sottile@polytechnique.fr, angel.rubio@ehu.es 

Porphyrin oligomers (short chains of porphyrins covalently linked by small molecular bridges) are of great 

interest nowadays for biosensors and optoelectronic industry. Thanks to the pi-coniugationthey are 

characterized by high polarizabilities, large oscillator strenghts and low electronic transitions. For these 

reasons they show much potential for efficient organic solar cells. 

These properties depend sensitively on particular structural components such as functional groups,the chain 

length and the type of central metal atom and the molecular bridge. All these factorsdetermine the formation 

and a different spatial localization of excitons.In this presentation we describe ab-initio calculations [1] of 

electronic and optical properties of free-base and Zinc porphyrines systems both as isolated molecules, 

oligomers and molecular crystals.The electronic excited states are obtained using the GW approach needed 

for a correct computationof the quasi-particle states, while the optical spectra and the excitonic properties are 

computedsolving the Bethe-Salpeter equation which fully describes the electron-hole coupled dynamics 

[2].A discussion about the optical features and the change of the exciton charactermoving from isolated 

molecules [3] to oligomers [4], or molecular crystals, will be done. 

[1] A.Marini, C. Hogan, M. Gruning, D. Varsano Comp. Phys. Comm. 180 (2009) 1392–140 

[2] G. Onida, L. Reining, A. Rubio, Rev. Mod. Phys. 74, 601 (2002) and references therein. 

[3] M. Palummo, C. Hogan, F. Sottile, P. Bagala', A. Rubio J. Chem. Phys. 131, 084102 (2009) 

[4] C. Hogan, M. Palummo, F. Sottile, A. Rubio, preprint 

10H00-10H20 

Self-assembly of Tetrathiafulvalene on Surfaces studying the Charge Transfer 

Phenomena. 

C. Simäo, M. Mas-Torrent, C. Rovira (ICMAB-CSIC., Campus de la UAB, 08193 Bellaterra, 

Barcelona, Spain). csimao@icmab.es 


The ultimate goal of molecular bottom-up approaches is to employ functional building blocks to construct 

nanometer scale devices addressed to specific applications. Furthermore, for practical device implementation 

the immobilization of functional molecules on suitable surfaces is also often required. In this work, we 

describe the preparation of self-assembly monolayers (SAMs) of electroactive molecules in order to have a 

molecular switch on a surface. 


The molecules employed were tetrathiafulvalenes (TTFs) derivatives, which are compounds that present two 

accessible redox states that exhibit different optical and magnetic properties that can be used as read-out 

responses. This bistability is required for fabricating molecular switches since, in this way, these systems can 

present „ON‟ and „OFF‟ states. The approach employed here is to construct a molecular switch on a surface 

is to fabricate a SAM with these bistable molecules on indium-tin oxide (ITO), which is a transparent 

106


conductive substrate thus one could control the switch electrochemically and use optical properties of the 

SAMs as read-out mechanisms. 

Besides the switching behaviour, the charge transfer properties of these compounds as donor-accpetors upon 

oxidation was studied on surface and were observed interesting optical phenomena. 


The study of charge transfer in donor-acceptor systems base don TTFs on surface is described. Furthermore 

it was possible to construct highly reproducible, stable and long-living switch on ITO using TTFs SAMs. 

10H20-10H40 

Light absorption by nanostructured metals. 

Nicolas Bonod, Evgeny Popov (Institut Fresnel, Domaine Universitaire de Saint Jérôme, 13397 

Marseille, France). 


More than one century ago, Wood discovered anomalies of reflection when metallic gratings were 

illuminated by a Transverse Magnetic polarized field [1]. In 1946, Fano explained these anomalies 

experimentally observed in 1902 by the excitation of resonant surface waves called Surface Plasmons 

Polaritons [2]. In 1974, Huthley and Maystre discovered for the first time that metals periodically structured 

can fully absorb light [3]. We will review in this talk the recent breakthroughs in the theory of light absorbers 

made of periodically structured metals. 


The major drawback of SPP for the conception of light absorbers is that light absorption occurs at a given 

angle of incidence. The use of localized plasmons permitted to broaden the range of incident angles [4-5]. 

We show that cylindrical cavities in a gold substrate, placed below the flat metallic surface induce a full 

absorption of light, without plasmons since the optical device is illuminated in Transverse Electric 

polarization. We evidence that this absorption is due to cavity resonances and that the enhancement of the 

light intensity inside the cavity leads to a full absorption in a wide range of incident angles [6]. Besides 

metallic structures, lossy dielectrics are good candidates for the design of light absorbers. In 2008, an 

absorbing layer consisting of very thin aligned carbon nanotubes has been proposed to fully absorb light [7]. 

The major drawback of this system is the requirement of a large thickness (300 µm). The use of structured 

metals permits to reduce the thickness of the absorbing layer [8-11]. We evidence that 1D or 2D lamellar 

gratings with a very short pitch behave like lossy dielectrics with a high real part value when their period 

tends toward zero (in the homogeneization limit). They present a metamaterial behaviour: nanostructured 

metals with a very short pitch behave like lossy dielectrics with very high refractive index. The 

nanostructured absorbing layer can be reduced to a few nanometers. 


Nanostructured metals are good candidate for conceiving light absorbers. We have shown that good 

absorbers can be achieved without the help of surface plasmons, and that ultrathin absorbers can be realized 

when the period of the nanostructuring is reduced to a few nanometers. 

107


[1] R. W. Wood, Phylos. Mag. 4, 396-402 (1902) 

[2] U. Fano, J. Opt. Soc. Am. 31, 213-222 (1941) 

[3] M. C. Hutley et al., Opt. Commun. 19, 431-436 (1976) 

[4] F. J. Garcia-Vidal et al., J. Lightwave Technol. 17, 2191-2195 (1999) 

[5] T. V. Teperik et al., Nat. Photon. 2, 299-301 (2008) 

[6] N. Bonod et al. Opt. Lett. 33, 2398-2400 (2008) 

[7] Z. P. Yang et al. Nanolett. 8, 446 (2008) 

[8] N. Bonod et al. Opt. Express 16, 15431-15438 (2008) 

[9] V. G. Kravets et al., Phys. Rev. B 78, 205405 (2008) 

[10] J. Le Perchec et al., Phys. Rev. Lett. 100, 066408 (2008) 

[11] E. Popov et al. Opt. Express 17, 6770-6781 (2009) 

10H40-11H00 Photophysical properties of alternated pyridine-ethylenedioxythiophene 

oligomers investigated with TD-DFT: towards light triggered molecular 

springs 


Claudine Katan (FOTON, INSA, CNRS, 20 avenue des buttes de Coësmes, CS70839, F-35708 RENNES 

Cedex 9, CPM, Unniversité Rennes 1, CNRS, campus de beaulieu, Case 1003, F-35042 RENNES Cedex). 

Claudine.Katan@univ-rennes1.fr 

Among the various organic systems designed for their optical and electronic properties, novel chromophores 

based on the alternation of electron-poor (pyridyl, A) and electron-rich (ethylenedioxythienyl, D) 

heterocycles have recently been shown to lead to dramatic enhancement of their photoluminescent properties 

with oligomer elongation [1]. These compounds adopt a coiled structure reminding the self-organized 

multiturn helical superstructures of alternating pyridine-pyrimidine oligomers [2]. The perspectives for 

photonic devices opened by such synthetic routes deserve better understanding of their structure-property 

relations. 


The aim of this work is to explore ground- and excited-state photophysical properties of such (DA)n 

chromophores with state of the art time dependent density functional theory (TD-DFT) approaches. 

Geometries are optimized at the HF/6-31G and TD-HF/SV level of theory, respectively while absorption and 

fluorescence points are treated at the TD-B3LYP level. Calculated data show good agreement with 

experimental X-ray data, transition energies, oscillator strengths and radiative lifetimes. Insight in the nature 

of the excited states relevant for absorption and emission is gained thanks to Natural Transition Orbital 

analysis. It reveals excited state localization prior to emission on one of the ADA moiety for derivatives with 

at least two A cycles. Computer design of 8-member oligomers is also performed. For the closed ring, 

calculations predict fluorescence quenching and steric hindrance that may hamper synthesis. The open 8- 

member derivative shows significant decrease of its helical pitch after excitation, with inhomogeneous 

torsion angles along the oligomer, as a consequence of excited state localization prior to emission. 


This suggests a new route towards reversible light triggered nanosprings. Such a route could be even further 

extended in the framework of molecular devices thanks to dissymmetrical functionalization which allows 

spatial control of emission localization [3] and/or by peripheral substitution [2] of active molecular moeties. 

[1] F. Chevalier, M. Charlot, C. Katan, F. Mongin and M. Blanchard-Desce, Chem. Commun., 2009, 692-694 

108


[2] M. Ohkita, J.-M. Lehn, G. Baum and D. Fenske, Chem. Eur. J. 1999, 5, 3471-3481. 

[3] C. Katan et al., to be published. 

11H30-11H50 

Structure of MgO nano-islands on metallic substrates: A semi-empirical, order 

N, Hartree-Fock simulation. 

C. Noguera*, J. Goniakowski*, J. Godet** (*Institut des Nanosciences de Paris, France. **Physique 

des matériaux, Poitiers). 

In the last decade, there have been intense efforts to synthetize ultra-thin oxide layers deposited on metal 

substrates. It has been recognized that, in most cases, their properties largely differ from their bulk 

analogues, and may be tuned as a function of orientation, thickness and support characteristics. Moreover, 

lateral confinement gives additional degrees of freedom for engineering artificial objects. However, at small 

sizes, nano-objects are strongly influenced by the interaction with the substrate, both electronically and 

structurally. This raises questions related to epitaxial growth, formation of Moiré patterns, presence of 

interfacial dislocations, and elastic relaxation at the interfaces. 

In order to decipher the microscopic mechanisms involved, atomistic numerical simulations are of great help. 

They can complement other approaches based on linear elasticity or theoretical models such as the Frenkel- 

Kontorova model. However, atomistic simulations of nano-oxides are presently subject to either sever size 

limitations if first principles methods are used, or suffer from a limited or absent account for the electronic 

degrees of freedom if classical methods are chosen (extended Born models, chemical potential equalization, 

etc). We have developed a semi-empirical Hartree-Fock simulation code, which scales linearly with the 

system size. It correctly treats the self consistent relationship between the charge distribution and the 

electrostatic potential acting on the electrons. The adjustable parameters are fitted as to reproduce 

experimental or first principles results on several periodic systems and on a variety of small clusters. In order 

to achieve order N scaling, a “divide and conquer” strategy is adopted. 

We will present the basis of the method, and discuss the epitaxial properties of metal-supported MgO square 

islands. We will discuss commensurability locking, interface dislocations, island magicity and local 

electronic properties. We will also show how these properties behave as a function of the strength of 

interaction with the substrate and of the lattice mismatch, thus producing a “phase diagram” in which size 

effects will be discussed. Finally, we will make a link with recent experimental results of MgO clusters or 

layers deposited on Ag(100) and Mo(100). 

Support of the French ANR-PNANO 2006 (project “SIMINOX” 009 03) is acknowledged. 

109


11H50-12H10 

Amorphous silicon-carbon alloys for efficient sensing through localized surface 

plasmon and fluorescence detection. 

L. Touahir1, E. Galopin2, R. Boukherroub2, J.-N. Chazalviel1, F. Ozanam 1, S. 

Szunerits2, A. C. Gouget-Laemmel 1* (1Physique de la matière condensée, Ecole Polytechnique – 

CNRS, France, 2Interdisciplinary Research Insitute (IRI), France). Anne-chantal.gouget@polytechnique.fr 


Biosensors based on the detection of fluorescence and/or surface plasmon resonance (SPR) are widely used 

owing to their ease of processing. Whereas fluorescence detection is more sensitive, SPR devices have the 

interest of allowing for a label-free detection. In most cases, the change in the resonance of propagating 

surface plasmons is detected. When surface plasmons are confined on metallic nanostructures, localized 

optical modes are observed, leading to highly localized electromagnetic fields in the vicinity of the particles. 

Localized surface plasmon resonance (LSPR) is sensitive to local refractive index changes that occur when 

surface reactions take place. The bonding of chemical and biological ligands to LSPR interfaces is mostly 

performed through the formation of Au-S bonds by the use of thiolated molecules, which can limit the 

sensing performances. 


We have designed LSPR biosensors based on a thin layer of hydrogenated amorphous silicon-carbon alloy 

(a-SixC1-x:H) deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD) on a gold 

nanostructure, with optimized optical sensitivity and surface chemistry. This allows for incorporating 

carboxyl–terminated molecules bound to the surface via Si-C covalent bonds. Such functions make the probe 

immobilization easy through reaction with amine terminations. The sensitivity is maximized by optimization 

of the amorphous layer thickness and the carbon content. 


DNA hybridization can be detected by following the change in the device absorbance. Using the same 

substrates, we can also detect the hybridization by fluorescence, which is enhanced by the LSPR. The 

obtained sensitivity allows for monitoring the hybridization of DNA probes with their complementary DNA 

in situ and in real time. Many successive hybridization/dehybridization cycles have been recorded without 

measurable changes. Quite low background fluorescence is measured, allowing for the convenient detection 

of the hybridization from low-concentration target solutions (down to 5 fM). 

12H10-12H30 

The Formation of Quantum Dots in Thin Nanostructured Films. 

Lyudmila Kveglis1, Riza Abylkalykova2, Viktor Zhigalov3 (1 Siberian Federal University, 2 

East Kazakhstan State Technical University, 3 Kirensky Institute of Physics SB RAS). kveglis@iph.krasn.ru, 

rabylkalykova@mail.ru, zhigalov@iph.krasn.ru 


In this work the nanocrystalline films with Frank-Kasper structure were examined as material for creating of 

quantum dots. An ability to create all-inorganic Quantum Dots may be considered for Co80C20, Tb30Fe70, 

Fe86Mn13C and Co50Pd50 films. 

110



The uniaxial magnetic anisotropy in film materials having large constant of magnetostriction is able to 

change its sign and value due to inner stress gradients created by dissipative structures. The correlation of 

nanocrystalline film structure with their magnetic characteristics in the process of transition from the 

disorder to their regular structure is researched. The other problem considered in this work is a decrease of 

saturation magnetization in nanocrystalline films of Co50Pd50 and Fe86Mn13C with tetrahedral closepacked 

Frank-Kasper structures. 


The data summarized in this paper demonstrated that in nanocrystalline films of metal alloys exists the 

possibility of the quantum dots creation in the form of nanocrystallites with Frank-Kasper structure. The 

appearance of this quantum dots one can connecting with spectrum of absorption, which shows visible 

distinct peaks at wavelength in the area of 1300 nanometers, apparently connecting with exiton optical 

transition. 

12H30-12H50 Tail effect on trihydroxysilanes dimerization: a DFT study. 


J.-M. Ducéré1,2, A. Estève1,2, G. Landa1,2, M. Djafari Rouhani1,2, D. Estève1,2 (1 

CNRS ; LAAS ; 7 avenue du Colonel Roche, F-31077 Toulouse, France, 2 Université de Toulouse ; UPS, INSA, 

INP, ISAE ; LAAS ; F-31077 Toulouse, France). jmducere@laas.fr, aesteve@laas.fr, landa@laas.fr, 

djafari@laas.fr, esteve@laas.fr 

Organosilanes self-assembled monolayers (SAMs) are widely used for inorganic surfaces modifications in 

the field of micro- and nanosystems for to improving the tribological properties, controlling the 

hydrophobicity, or introducing chemical functions for further grafting. Obviously, the silane organic tail is 

critical for the quality of the so-formed layer. In particular, short alkyl chains and polar groups are known to 

lead to highly disordered layers. 

In this context, we have already used Density Functional Theory calculations to investigate the hydrolysis 

and grafting to silica. Here, we study the influence of the length of terminating alkyl chain and of the 

presence of a polar group on trihydroxysilanes dimerization, that can be viewed as the very initial step of the 

self-assembly process. 


In a first time, we consider silanes terminated by two different polar groups: an amine and an ester. We 

obtain that the stablest conformation is, in both cases, a head-to-tail one. Indeed, this conformation is favored 

because hydrogen-bonds between a silanol and an amine or ester group are stronger than between two 

silanols. 

In a second time, we investigate alkyl chains of different lengths (C3-C30). Here, the geometry is a 

compromise between silanes heads hydrogen-bonds, keeping chains apart, and London interaction, keeping 

chains parallel. For chains as short as C6, London interaction dominates but substantially longer chains (C12, 

C18) are required for parallel chains being significantly stabler. 

111



Through the use of DFT calculations, we are able to rationalize tail-related organosilanes features. Indeed, 

we propose structural patterns that explain the higher disorder in SAMs formed from short alkyl chains or 

polar groups terminated silanes. 

4 – References 

A. Dkhissi , A. Estève, L. Jeloaica, D. Estève, M. Djafari Rouhani, Chem. Phys. Lett. 2004, 400, 353. 

A. Dkhissi, A. Estève, L. Jeloaica, D. Estève, M. Djafari Rouhani, J. Am. Chem. Soc. 2005, 127, 9776. 

A. Dkhissi, A. Estève, L. Jeloaica, M. Djafari Rouhani, D. Estève , Comp. Mat. Sci. 2005, 33, 282. 

A. Dkhissi, A. Estève, L. Jeloaica, M. Djafari Rouhani, G. Landa , Chem. Phys. 2006, 323, 79. 

A. Dkhissi, A. Estève, M. Djafari-Rouhani, L. Jeloaica, J. Phys. Chem. C 2008, 112, 5567. 

J.-M. Ducéré, A. Estève, A. Dkhissi, M. Djafari Rouhani, G. Landa, J. Phys. Chem. C 2009, 113, 15652. 

17H00-17H30 

Metallic Nanocrystals and Nanoalloys obtained by soft chemistry: Growth 

process and self-organization into 2D and 3D super crystals. 

C.PETIT (Université Pierre et Marie Curie-Paris 6; CNRS UMR 7070, LM2N, 4 place Jussieu 75005 Paris, 

France). 

Research in the field of nanoparticles has grown tremendously during the last two decades. Such inorganic 

nanocrystals are of interest for a variety of applications such as superparamagnets, semiconductors or 

catalysis. Thus it is important to have access to methods that give particles in the nanometer range with good 

control over size, shape and composition but also with the potential for controlled deposition on a solid 

supPort-Pin supercrystals. Depicted numerous study on these nanomaterials, the understanding of 

nanocrystal growth and control of nanomorphology is not well defined. 

We details here the use of the liquid-liquid phase transfer to obtain either pure metallic Platinum or 

Palladium nanocrystals with a control of the size and shape but also for the first time magnetic nanoalloys, as 

CoPt, with a perfect control on the composition and size. We will emphasize on the parameters allowing 

control the growth process and then the physical characteristic of the inorganic nanocrystals. 

The low size polydispersity allows these nanocrystals to self-assemble with a long-range ordering in 2D and 

3D super-crystals. The control of shape induces change in the Van der Waals interaction between the 

nanocrystal and thus a change in the growth process of the supercrystals. Hence, according to the nanocrystal 

shape, simple cubic or face centered cubic super-crystals are observed. It is remarkable to notice that wellfacetted 

supercrystals with sizes of the order of 10 micrometers may be obtained. 

112


[1]-K.Wikander, C. Petit, K. Holmberg and M.P.Pileni, Size controlled and growth process of alkylamine-stabilized platinum nanocrystals : a 

comparison between the phase transfer and the reverse micelles methods Langmuir, 22,4 863,(2006) 

[2]- A. Demortières and C. Petit, First synthesis by liquid-liquid phase transfer of magnetic CoxPt100-x Nanoalloys Langmuir 23, 8575, (2007) 

[3]- K. Naoe, C. Petit and M.P. Pileni From worm-like to spherical palladium nanocrystals : digestive ripening J. Phys. Chem C, 110, 16249, (2007) 

[4]- K. Naoe, C. Petit and M.P. Pileni Use of Reverse Micelles to Make Either Spherical or Worm-like Palladium Nanocrystals: Influence of 

Stabilizing Agent on Nanocrystal Shape Langmuir 24, 2792 (2008) 

[5]- A. Demortière, P. Launois, N. Goubet, P-A. Albouy and C. Petit ; Shape-Controlled Platinum Nanocubes and their Assembly into 2D and 3D 

Superlattices J. Phys. Chem B 112, 14583,(2008) 

17H30-17H50 

The effect of ethanol vapor on metal-induced fluorescence enhancement. 

Wout Knoben, Peter Offermans, Sywert H. Brongersma, Mercedes Crego-Calama 

(Holst Centre/IMEC - High Tech Campus 31, 5656 AE Eindhoven, The Netherlands). wout.knoben@imec-nl.nl; 

peter.offermans@imec-nl.nl; sywert.brongersma@imec-nl.nl; mercedes.cregocalama@imec-nl.nl 

Introduction 

Fluorescence is a popular detection mechanism in (bio)chemical sensing. Recently, two promising 

developments have emerged in this field. Firstly, increased sensitivity is obtained by using fluorescence 

enhancement by localized surface plasmons in metal nanoparticles (NP). Secondly, using quantum dots (QD) 

as fluorophores improves sensor stability and lifetime. It becomes even more interesting if these two are 

combined. The sensitivity of QD fluorescence and localized surface plasmons to their environment is well 

known, and both are being used independently for detection of organic vapors and other (bio)chemicals. 

However, we have investigated the effect of environmental changes on the optical coupling between NP and 

QD, that is, on the metal-induced fluorescence enhancement. 

Results 

QD, embedded in a polymer matrix were deposited on top of arrays of ordered Au NP. The presence of the 

Au NP results in enhanced fluorescence, which depends on the size and pitch of the NP and the thickness of 

the QD/polymer film. Moreover, the enhancement factor is affected by exposure to ethanol vapor. The 

vapor-induced change in enhancement factor also depends on the size and pitch of the Au NP. The results are 

explained by vapor-induced swelling of the polymer, which increases the average distance between Au NP 

and QD and affects their optical coupling. Thus, fluorescence enhancement by metal NP can not only be 

used for improving the sensitivity of fluorescence intensity based sensors, the enhancement factor itself also 

provides an additional detection mechanism. 

Conclusion 

This is the first report of changes in the fluorescence enhancement factor in response to vapor exposure. This 

phenomenon provides a new transduction mechanism that can improve both the sensitivity and the 

selectivity of fluorescence-based vapor detection. 

113


17H50-18H10 

Nanodesign of metallic catalysts : well defined metallic nanoparticles supported 

on alumina. 

C. Thomazeau a, L. Bisson a,b, J. Aguilhon a,b, C. Boissière b, O. Durupthy b, C. 

Sanchez b ( a IFP-Lyon, Rond-point de l'échangeur de Solaize, BP 3 - 69360 Solaize - France; b Laboratoire de 

Chimie de la Matière Condensée de Paris, LCMCP, Collège de France, Bât. C-D, 11 place Marcelin Berthelot, 

75231 Paris Cedex 05, France). 

In the field of catalysis by metals, catalysis research efforts were until today essentially focused on 

dispersion and particles size effects onto catalytic properties 1. Conventional metallic catalysts are 

constituted with supported nanoparticles, which are usually represented by a truncated cuboctahedra 2. These 

nanoparticles present several different active sites: (111) and (100) facets, corners and edges, each one with 

different catalytic properties. Nevertheless, it has recently been established, for a set of various reactions that 

both activity and selectivity are highly dependent on the morphology of nanoparticles and reactions 

conditions 3. Indeed, the use of nanoparticles with particular shapes (rods, cubes, tetrahedra ...) induces a 

precise control of their surface structure: type of exposed crystallographic planes, proportion between atoms 

on corners, edges or facets, thus giving the possibility to tune the activity and/or the selectivity of a catalytic 

system for a given reaction. This is a new insight for the nanodesign of catalysts. 

The growing interest for the control of metallic nanoparticules shapes with applications in catalysis, will be 

illustrated through literature examples. The IFP contribution will also be presented. More precisely, methods 

of synthesis developed to obtain a set of metallic well-facetted nanoparticules (Pd, Pt, Ni) in aqueous 

medium will be exposed. Then, structure-activity relationships observed for the supported catalysts obtained 

by deposition of the well-facetted nanoparticules on alumina will be explained for the selective 

hydrogenation reaction unsaturated hydrocarbons 4,5. 

[1] J.P. Boitiaux, J. Cosyns, S. Vasudevan, Appl. Catal. 6 (1983) 41 

[2] Van Hardeveld, R., Hartog, F., Surf. Sci., 15 (1969) 189 

[3] Somorjai et coll., Angew. Chem. Int. Ed., 2008, 47, 9212 

[4] Di Gregorio F. et coll., Appl. Catal, 352 (2009) 50 

[5] Bisson L. et coll, in press 

18H10-18H30 Self-assembly of gold nanoparticles on functional organic molecular crystals. 

Silvia Trabattoni, Massimo Moret, Marcello Campione (University of Milano-Bicocca, 


Department of Materials Science, via Cozzi 53, I-20125, Milan). silvia.trabattoni@mater.unimib.it; 

marcello.campione@unimib.it. 

The performance of molecular based electronic devices is mainly determined by charge carrier generation 

and transport properties and by organic-metal interfacial characteristics. Indeed, charge transport mainly 

occurs by carrier injection/extraction through the electrode interface, since molecular semiconductors are 

hardly doped and poor of free charge. The organic-electrode interface can be obtained in different geometries 

depending on the device type. In organic thin film transistors (OTFTs) the organic-metal interface is usually 

obtained in top-contact geometry, i.e. the metal is deposited on the active organic substrate. Traditional 

deposition techniques, such as vacuum sublimation and ionic beam deposition, can damage the surface of 

organic materials; in particular the metal diffusion phenomena and the high temperatures required during 

sublimation process can produce short circuits or irreparably damage the organic layer. 

114



Many efforts have been done to find techniques that allow forming a metal layer under ambient conditions, 

avoiding the aforementioned problems. A possible solution is to operate in liquid phase at room temperature 

and pressure using metal nanoparticles (NPs) in colloidal solution. The peculiar physic-chemical properties 

of NPs make them suitable as precursors for metal electrodes. In the literature some procedures for the 

deposition of metal NPs by drop casting and ink-jet methods on many kinds of substrates, both inorganic 

(silica, mica, HOPG) and organic (commercial polymers and molecular organic thin films) are described; 

however, to our best knowledge, very few works concern the deposition of metal NPs on organic molecular 

single crystals. In this work we describe the deposition of gold NPs from colloidal solution on crystals of 

tetrafluoroacridines to evaluate the specific reactivity of organic crystal surfaces versus gold. In particular, 

two iso-structural crystals have been considered: the first one exposes a large number of sulfur atoms just 

underneath the largest crystal face and the second one exposes the same number per surface area of oxygen 

atoms. The deposition of NPs has been carried out at room temperature by drop-casting, depositing a precise 

volume drop and removing it after a settled time. Samples have been characterized by atomic force 

microscopy (AFM) to evaluate coverage, self-assembly dynamics and aggregate dimensions. 


While tetrafluoro-7-methoxyacridine crystals show no propensity to induce a self-assembly of gold NPs, a 

uniform distribution of NPs has been obtained on tetrafluoro-7-thiomethylacridine crystal surface, thanks to 

the presence of sulfur atoms on the surface. By increasing deposition time, the amount of NPs on the crystal 

surface increases; moreover, the quantity of NPs adsorbed on the crystal surface is related to NP size. 

115

P R O G R A M FRIDAY, JULY 2 N A N O S E A 2 0 1 0 

Friday, July 2 

Session 18 

Room Calendal 

Mesoporous Systems (Chairman: ) 

9H00-9H30 

GROSSO ((1) Laboratoire Chimie de la Matiere Condensée de Paris, UMR UPMC-CNRS 7574, Université 

Pierre et Marie Curie (Paris 6), Collège de France, 11, place Marcelin Berthelot, 75231 Paris). 

Bottom-up elaboration of heterogenous ordered ceramic nanopatterns substrates for 

deposition of magnetic materials 

9H30-9H50 CRESPO-MONTEIRO (1 Université de Lyon, F-42023 Saint-Etienne, France; CNRS, UMR 5516, 

Laboratoire Hubert Curien, 18 rue Pr. Lauras F-42000 Saint-Etienne, France; and Université de Saint-Etienne, Jean- 

Monnet, F-42000 Saint-Etienne, France; 2 Laboratoire Multimatériaux et Interfaces, Université Claude Bernard 

Lyon 1, Bat Berthollet, 69622 Villeurbanne, France). 

Photochromic silver-containing mesoporous TiO2 films as writable and rewritable 

data carriers 

9H50-10H10 

KELLER (Department of Materials Engineering, Technion, Haifa 32000, Israel). 

Influence of Confinement on the Self Assembly of Opto-Electronically Active 

Mesostructured Hexagonal Silica 

10H10-10H30 

HORNEBECQ (Laboratoire Chimie Provence, Université Aix-Marseille-CNRS UMR6264, Marseille 

France). 

A simple relationship to predict the pore size of ordered mesoporous silicas 

10H30 - 11H00 


116


Session 19 

Room Calendal 

Self Assembly (Chairman: Noguera) 

11H00-11H20 DANIELE (a Institut de Recherches sur la Catalyse et l‟Environnement de Lyon (IRCELYON), UMR 5256; 2 

avenue Albert Einstein; 69626 Villeurbanne cedex, France; b Institut de Chimie Séparative de Marcoule (ICSM), 

UMR 5257, site de Marcoule, BP 17171, 30207 Bagnol sur Cèze, France). 

Remarkable self-assembly effect in hybrid TiO2 systems elaborated by chemical 

design: Applications in cosmetics, ionic selective separation and catalysis. 

11H20-11H40 NISTOR (National Institute of Materials Physics, Atomistilor 105bis, POB MG 7, Magurele-Ilfov, 077125 

Romania). 

Local structure at substitutional Mn2+ ions in small cubic ZnS nanocrystals selfassembled 

into a mesoporous structure. 

11H40-12H00 

DELAFOSSE (1 Aix-Marseille Université, IM2NP; 2 CNRS, IM2NP (UMR 6242); 3 Institut Supérieur de 

l‟Electronique et du Numérique, IM2NP Maison des Technologies, Place Georges Pompidou, F-83000 Toulon, 

France). 

Fullerenes C60 self-assembled on functionalized surfaces. 

12H00-12H20 

CHITU (1Institute of Physics, Slovak Academy of Science, Dubravska cesta 9, 84511 Bratislava, Slovakia, 

2Polymer Institute Slovak Academy of Science, Dubravska cesta 9, 84236 Bratislava, Slovakia, 3International Laser 

Center and Faculty of Electrical Engineering and Informatics SUT, 81219 Bratislava, Slovakia, 4HASYLAB 

/DESY, Notkestr. 86, 22603 Hamburg, Germany, 5Erich Schmid Institute for Materials Science, Austrian Academy 

of Sciences, Jahnstrasse 12, A-8700 Leoben ,Austria, 6Materials Center Leoben Forschung GmbH, Roseggerstraße 

12, A-8700 Leoben, Austria). 

Modified Langmuir-Blodgett deposition of nanoparticles for preparation of large 

area ordered 2D and (2+1)D arrays. 

12H20-12H40 

Room Calendal : Nanomaterials and Nanotechnology Concluding Remarks. 

117


Session 20 

Room Port-Pin 

Carbon Nanotubes (Chairman: Berbezier) 

9H00-9H30 

CASTRUCCI (1Dipartimento di Fisica and Unità CNISM, Università di Roma Tor Vergata Via della Ricerca 

Scientifica 1, I-00133 Roma, Italy; 2 Dipartimento di Igiene del Lavoro, ISPESL, I-00040 Monte Porzio Catone, 

Italy). 

Improving photovoltaic response of CNTs/Si heterojunctions using different carbon 

nanotubes types and CNTs film thicknesses. 

9H30-9H50 

SINDONA (DIPARTIMENTO DI FISICA, UNIVERSITA‟ DELLA CALABRIA and INFN, Gruppo Collegato 

di COSENZA, VIA P: BUCCI, CUBO 31C, 87036 RENDE (CS), ITALY). 

Many Body Shake Up in Core-Valence-Valence Electron Emission from Single 

Wall Carbon Nanotubes. 

9H50-10H10 GROSSI (Dipartimento di Fisica, Università degli Studi dell'Aquila, Via Vetoio 10, 

I-67100 Coppito (L'Aquila), Italy). 

High photoconductivity in carbon nanotube sheets. 

10H10-10H30 

SCARSELLI (1Dipartimento di Fisica and Unità CNISM, Università di Roma Tor Vergata Via della Ricerca 

Scientifica 1, I-00133 Roma, Italy, 2 Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma Tor 

Vergata, Via della Ricerca Scientifica 1, I-00133 Roma, Italy, 3 Dipartimento di Igiene del Lavoro, ISPESL, I-00040 

Monte Porzio Catone, Italy). 

Tuning Photoresponse through Size Control of Cu nanoparticles deposited on multi 

wall carbon nanotubes. 

10H30 - 11H00 


118


Session 21 

Room Port-Pin 

Nanotubes and Coatings (chairman: Goniakowski) 

11H00-11H20 

BELLUCCI (INFN – LNF, via E. Fermi, 40, 00044 Frascati (RM) Italy). 

Carbon nanotube based composites: electrical and mechanical properties. 

11H20-11H40 

CAPASSO (1Queensland University of Technology, Brisbane, Australia; 2Australian National University, 

Canberra, Australia; 3 University of Rome “Tor Vergata”, Rome, Italy). 

Ordered growth of multi-walled nanotubes on Ge nanocrystals. 

11H40-12H00 ZAPOROTSKOVA (Volgograd State University, Volgograd, 400062, Universitetskii prospect, 100, 

Russia). 

Boron Nanotubes and its properties: semiempirical investigations; 

12H00-12H20 

SPIESSER (1 Centre Interdisciplinaire de Nanoscience de Marseille (CINaM-CNRS), Aix-Marseille Université, 

Campus de Luminy, case 913, 13288 Marseille, France) 

Epitaxial growth and magnetic properties of Mn5Ge3 compound on Ge(111) 

12H20-12H40 

Room Calendal : Nanomaterials and Nanotechnology Concluding Remarks. 

119

A B S T R A C T S FRIDAY, JULY 2 N A N O S E A 2 0 1 0 

Room Calendal 

9H00-9H30 

Bottom-up elaboration of heterogenous ordered ceramic nanopatterns 

substrates for deposition of magnetic materials. 

D. Grosso*(1), M. Faustini(1), D. Lantiat(1), C. Laberty(1) ((1) Laboratoire Chimie de la 

Matiere Condensée de Paris, UMR UPMC-CNRS 7574, Université Pierre et Marie Curie (Paris 6), Collège de 

France, 11, place Marcelin Berthelot, 75231 Paris).* presenting author, e-mail: david.grosso@upmc.fr 

Ceramic (e.g. semiconducting TiO2, or insulating ZrO2, Al2O3) nanopatterns on various substrates (e.g. Si, 

Au, SiO2, Cr) have been prepared through simple fast, cheap, reproducible, and easy to scale up “bottom-up” 

approach, involving chemical solution deposition, self-assembly via commercial block copolymers, and 

thermal treatment.[1] The patterns is composed of hexagonally arranged nanoperforations through which the 

surface of the substrate remains accessible. The typical thickness of the patterns can be controlled between 5 

and 20 nm, while a proper selection of chemical and processing conditions allows to perfectly adjust the 

motif dimension between 10 and 100 nm.[2] They constitute novel highly ordered heterogeneous 

Inorganic/inorganic Nano Patterned (INP) substrates, which present a unique combination of thermal, 

mechanical, and chemical stability with the very interesting characteristics of the ordered nano-heterogeneity 

associated to the accessibility of the substrate surface through the perforations. 

Figure 1. From left to right: Bare TiO2 perforated Inorganic NanoPattern (INP); Prussian Blue Analogue chemically growth inside the INP‟s 

perforations;[3] FePt nanoparticles co-electrochemically generated inside the INP‟s perforations;[4] CoPt percolated media deposited by MBE onto 

the INP;[5] and Ge nanoparticles elaborated by Solid dewetting onto the INP. 

In the present contribution, we will first describe how this novel generation of substrates is prepared and how 

one can perfectly control the morphology and the dimensions of the nanoperforation motifs. We will then 

show how the ordered topography and chemical heterogeneity can be utilised to direct the distribution of 

deposited materials. Several examples, gathering chemical and physical deposition processes as shown in 

Figure 1, will be reported as illustration and demonstration. 

[1] D. Grosso, C. Boissière, B. Smarsly, T. Brezesinski, N. Pinna, P. A. Albouy, H. Amenitsch, M. Antonietti, C. Sanchez, Nature Materials, 3, 787, 

(2004). 

[2] M. Kuemmel, J. Allouche, L. Nicole, C. Boissière, C. Laberty, H. Amenitsch, C. Sanchez and D. Grosso, Chem. Mater. 19, 3717, (2007). 

[3] S. Lepoutre, D. Grosso, C. Sanchez, G. Fornasieri, E. Rivière, A. Bleuzen, Adv. Mater. (submitted). 

[4] J. Allouche, D. Lantiat, M. Kuemmel, M. Faustini, C. Laberty, C. Chaneac, E. Tronc, C. Boissiere, L. Nicole, C. Sanchez, D. Grosso, J Sol-Gel 

Sci Technol (online published). 

[5] D. Makarov, P. Krone, D. Lantiat, C. Schulze, A. Liebig, C. Brombacher, M. Hietschold, S. Hermann, C. Laberty, D. Grosso, and M. Albrecht, 

IEEE Trans. Magn. 45, 3515 (2009). 

120


9H30-9H50 

Photochromic silver-containing mesoporous TiO2 films as writable and 

rewritable data carriers. 

N. Crespo-Monteiro,1 N. Destouches,1 L. Bois,2 F. Chassagneux, 2 S. Reynaud1 (1 

Université de Lyon, F-42023 Saint-Etienne, France; CNRS, UMR 5516, Laboratoire Hubert Curien, 18 rue Pr. 

Lauras F-42000 Saint-Etienne, France; and Université de Saint-Etienne, Jean-Monnet, F-42000 Saint-Etienne, 

France; 2 Laboratoire Multimatériaux et Interfaces, Université Claude Bernard Lyon 1, Bat Berthollet, 69622 

Villeurbanne, France). 


Silver species adsorbed on colloidal titania have been known for a long time to exhibit photochromism [1-2]. 

They reversibly change their color in response to light exposure. The silver salts are reduced under UV light 

leading to silver nanoparticles that are oxidized under visible light. Recently, photochromic Ag/TiO2 

nanocomposite films have been studied for holographic data storage and smart glasses [3]. Here, we 

demonstrate that silver-containing mesoporous titania films can be used as writable and rewritable data 

carriers. We perform both permanent and erasable micro-inscriptions by using continuous lasers at various 

wavelengths under different experimental conditions. We also investigate the irreversible and the reversible 

mechanisms leading to the non erasable and erasable photoinscriptions, respectively. 

2 – Experimental section 

The mesoporous titania films were prepared following an evaporation-induced self-assembly route using 

non-ionic amphiphilic triblock copolymer P123 as structuring agent and tetrabutylorthotitanate (TBT) as 

titanium oxide precursor [4]. The films were deposited by dip-coating on cleaned glass slides. After drying, 

the copolymer was extracted with hot ethanol in a Soxhlet apparatus, and the films were soaked in the 

aqueous ammoniacal silver solution. 

The formation of silver nanoparticles was realized by UV-laser exposures at 244 nm or 325 nm wavelength. 

The photo-oxidation of silver nanoparticles was realized by visible laser exposures at 488nm, 514 or 633 nm. 

The formation and oxidation of silver nanoparticles was characterized by absorption spectroscopy, scanning 

electron microscopy, transmission electron microscopy and optical microscopy (local coloration of the 

sample). Raman spectroscopy was used for the characterization of the TiO2 crystallization and atomic 

microscopy force for the measurement of the film topography. 

3 – Results 

The UV wavelengths are used to locally reduce silver salts in the film. These wavelengths are absorbed by 

the TiO2 matrix that emits photoelectrons leading to the formation of silver nanoparticles in the film. Under 

visible light, the incident photons excite the particle surface plasmon that decays into other electrons 

excitations. The photoexcited electrons on Ag are transferred via TiO2 and non-excited Ag nanoparticles to 

oxygen molecules, which act as trapping centers. Therefore the silver nanoparticles are oxidized. 

We first study the influence of the incident UV-laser intensity on the photochromic behaviour of the film and 

evidence that microinscriptions can be reversibly or irreversibly printed in the same material, depending on 

the UV-laser intensity. The microinscriptions can be completely erased with a monochromatic visible 

illumination and we demonstrate the rewritability of the films by printing several successive 

microinscriptions in the same place without change of contrast. We also investigate the effect of a visiblelaser 

illumination at different intensities and wavelengths. We demonstrate that, depending on the incident 

121


intensity, visible light can be used to erase UV-printed micropatterns or photoprint non erasable 

microinscriptions in the films. The non erasable patterns are actually engraved in the film: the TiO2 matrix, 

initially amorphous, locally crystallizes into an anatase lattice, and depresses, under the focused illumination. 


Different monochromatic UV beams are used to print erasable or permanent microinscriptions, depending on 

the incident intensity. Various visible laser beams are used to erase the UV printed patterns, or to print 

permanent micropatterns, depending on the incident intensity. The reversible character of the erasable 

microinscriptions results from the photochromic character of the films whereas the permanent character of 

the non erasable microinscriptions is due to an irreversible crystallization of the TiO2 matrix. 

References : 

[1] A. Goetz, E. C. Y. Inn, Review of Modern Phys. 1948, 20, 131. 

[2] W. C. Clarks, A. Vondjdis, Nature 1964, 203, 635. 

[3] Q. Qiao, X. Zhang, Z. Lu, L. Wang, Y. Liu, X. Zhu, J. Li, Appl. Phys. Lett. 2009, 94, 074104-1. 

[4] L. Bois, F. Chassagneux, Y. Battie, F. Bessueille, L. Mollet, S. Parola, N. Destouches, N. Toulhoat, N. Moncoffre, Langmuir 2009, DOI: 

10.1021/la902339 

[5] J. Okumu, C. Dahmen, A. N. Sprafke, M. Luysberg, G. Von Plessen, M. Wuttig, J. Appl. Phys. 2005, 97, 094305-1 

9H50-10H10 

Influence of Confinement on the Self Assembly of Opto-Electronically Active 

Mesostructured Hexagonal Silica. 

Avigail Keller and Gitti L. Frey (Department of Materials Engineering, Technion, Haifa 32000, Israel). 

avigail@tx.technion.ac.il 


Mesostructured silica is used in diverse applications including separation technologies, heterogeneous 

catalysis, drug release, and photonics. The type of mesophase deposited from sol-gel solutions, i.e lamellar, 

cubic or hexagonal, depends on the precursor solution composition, relative humidity and the deposition 

technique. The orientation of the mesophases, on the other hand, is determined by the substrate and the 

deposition technique, with the 2D phases, i.e. lamellar and hexagonal, generally formed parallel to the 

substrate. However, a vertical alignment of the hexagonal mesophase is desirable for many applications. 

Deposition of mesostructured silica inside the vertical pores of a porous membrane such as anodic alumina 

membrane (AAM) has been shown to induce the desirable vertical alignment of the hexagonal silica. 


The objective of this research is to deposit photo-active hexagonal silica vertically aligned in porous AAM. 

To do so we use a new and general synthetic approach developed in our group for the incorporation of optoelectronically 

active guests, conjugated polymers, into the hexagonal silica upon its formation. 

The method used for the self assembly of the mesoporous silica/surfactant/conjugated polymer 

nanocomposite within the pores of an anodic alumina membrane includes soaking the 60 µm thick 

membrane in a modified sol-gel precursor solution including the hydrophobic optically-active organic guest, 

in this study a conjugated polymer species. More specifically, the precursor solutions contain THF as the 

main solvent, PluronicTM P123 as a structure directing agent, and TEOS as the silica precursor, P123 to 

TEOS molar ratios and relative humidity conditions were controlled. After soaking the AAM with the 

122


appropriate solution, self assembly of the ordered mesostructure in the pores is driven by the evaporation of 

the THF from the solution (EISA method). After drying the membranes were withdrawn from the 

experimental chamber and their surfaces were cleaned off prior to charecterization. Samples were 

characterized by transmission electron microscopy (TEM) and grazing incidence small angle x-ray scattering 

(GISAXS) measurements. It was found that the P123 concentration and/or relative humidity conditions 

determine the type of mesostructures formed within the pores and the in-pore filling. 

Our results demonstrate that high humidity conditions lead to well ordered in-pore mesostructure formation. 

Furthermore, increasing the surfactant concentration leads to better filling of the pores and gives rise to the 

formation of the desired vertically aligned hexagonal mesostructure within the pores. In addition to the 

synthesis conditions our results indicate a strong influence of pore shape on the orientation of the 

mesostructure; while round or elliptical pores induce the parallel orientation, less regular or triangular-like 

pores induce the desirable vertical orientation. 

Figure 1. Schematic drawing of the in-pore mesostructure 

a) The horizontal hexagonal phase and b) The vertical 

hexagonal phase. c) A top view TEM image of porous 

alumina membrane (in black) with an hexagonal 

silica/P123 mesostructure filling the pore. In this image 

most of the pore is filled with the horizontal hexagonal 

phase, but in the center of the pore the vertical orientation 

can be seen. 


Silica Mesostructures can indeed be formed in the pores of an alumina substrate using the THF-based sol-gel 

synthesis and P123 as structure directing agent. Using this synthesis conjugated polymers can be 

incorporated at the organic core of the mesostructure. Slower evaporation of the solvent, achieved by high 

humidity conditions or higher surfactant concentration, leads to well ordered phases and more vertically 

aligned hexagonal phases. Finally, the pore shape was shown to be of great influence on the orientation of inpore 

structure. 

1. Platschek, B., Petkov, N. & Bein, T. Tuning the Structure and Orientation of Hexagonally Ordered Mesoporous Channels in Anodic 

Alumina Membrane Hosts: A 2D Small-Angle X-ray Scattering Study. Angew. Chem. Int. Ed. 45, 1134-1138 (2006). 

2. Kirmayer, S., Dovgolevsky, E., Kalina, M., Lakin, E., Cadars, S., Epping, J. D., Fernández-Arteaga, A., Rodríguez-Abreu, C., Chmelka, B. 

F.& Frey, G. L. Syntheses of Mesostructured Silica Films Containing Conjugated Polymers from Tetrahydrofuran−Water Solutions. Chem. Mater. 

20, 3745-3756 (2008). 

123


10H10-10H30 

A simple relationship to predict the pore size of ordered mesoporous silicas. 

V. Hornebecq, T. Phan, P.L. Llewellyn and E. Bloch (Laboratoire Chimie Provence, Université 

Aix-Marseille-CNRS UMR6264, Marseille France). Virginie.Hornebecq@univ-provence.fr. 


The development of mesoporous silica presenting large and accessible pores has received much attention 

because of their potential applications involving large molecules including enzymes and proteins. Other 

potential applications have been suggested in adsorption, separation, catalysis, as nanodevices or photonic 

waveguides. Numerous studies have focused on the surfactant „structure directing agent‟ (or SDA) itself in 

order to obtain such mesoporous silica having the required pore size and accessibility. In these cases, diblock 

and triblock copolymers are often used as SDA‟s. However, whilst well structured materials have been 

obtained, very few studies have been devoted to understand the role of each block on the inorganic materials 

so obtained. Such work is essential for those looking to prepare mesoporous silica materials for a specific 

application where well controlled pore size and geometry are required. The present study is aimed at filling 

this gap in the case where amphiphilic PEO-b-PS diblock copolymer SDA‟s are used. 


Mesoporous silicas with large and accessible pores have been successfully synthesized using laboratorymade 

poly(ethylene oxide)-b-polystyrene (PEO-b-PS) copolymers as SDA‟s. The PEO-b-PS copolymers 

were synthesized using living/controlled radical polymerization; the size of micelles they form in solution 

was determined by dynamic light scattering experiments. The porous structure (mesopore size, size 

distribution, and microporous volume) was characterized using small-angle X-ray scattering, electron 

transmission microscopy, and nitrogen sorption measurements. 

In this study, we have investigated the dependence of the mesoporosity on both the PS and PEO blocks 

length using two series of PEO-b-PS copolymers with a constant degree of polymerization of the PEO block 

for each series (NPEO=114 and NPEO=232). It was found that the mesopore size increases and the 

microporous volume decreases as the PS block length (NPS) increases. The PEO block participates to both 

the micropore and mesopore formation. By fitting these experimental data, a simple empirical relationship 

between the pore radius and the length of the both PS block (NPS) and PEO block (NPEO) is found: . This 

relationship is in agreement for both low- and high-molecular-weight copolymers and can be easily be used 

to fine tune the mesopore size of silica materials, in a large range (from 4 to 22 nm), when using PEO-b-PS 

copolymers as templates. Furthermore, the influence of the synthesis temperature (between 25 and 60°C) on 

the porous structure was also investigated and it was found that by increasing the synthesis temperature, the 

mesopore diameters remain relatively constant; however, the pore entrances increase in size, leading to more 

open pore structures. 


This work has allowed a simple empirical relationship to be proposed that is based on that found for the 

diblock copolymer micelle formation in solution. This relationship has been verified against numerous 

samples made in the framework of this study and with others previously documented in the open literature. 

This relationship seems to hold for a large variation in degrees of polymerization of either PS or PEO block. 

It can thus be used to prepare silica materials with pore diameter from few nanometers to more than 20 nm. 

This therefore opens the possibility, for the first time, to predict and fine tune large pore mesoporous 

materials for specific applications. 

124


11H00-11H20 

Remarkable self-assembly effect in hybrid TiO2 systems elaborated by chemical 

design: Applications in cosmetics, ionic selective separation and catalysis. 

Raed Rahala, Fatima Annania, Stéphane Pellet-Rostaingb, Stéphane Danielea (a Institut 

de Recherches sur la Catalyse et l‟Environnement de Lyon (IRCELYON), UMR 5256; 2 avenue Albert Einstein; 

69626 Villeurbanne cedex, France; b Institut de Chimie Séparative de Marcoule (ICSM), UMR 5257, site de 

Marcoule, BP 17171, 30207 Bagnol sur Cèze, France). raed_rahal@hotmail.com, fatima.annani@ircelyon.univlyon1.fr, 

stephane.daniele@ircelyon.univ-lyon1.fr, stephane.pellet-rostaing@cea.fr 


Hybrid oxide (TiO2) nanostructured materials, which combine the properties of inorganic and organic 

constituents, have a large range of uses in the fields of composite materials, separation, catalysis, electrical 

and optical devices or in the biomedical area.1 The control of the aforementioned properties of the resulting 

nanomaterials depends strongly on the control of parameters such as size, shape, crystallinity, phase 

composition of the oxide nanoparticles, nature of bonding and interface between the organic and the 

inorganic phases, the nature and the amount of the organic component and finally the degree of dispersion of 

the nanoobjects. Whereas elaborations of valuable functional inorganic mesostructures from nanostructured 

TiO2 hybrid particles of controlled size, morphology and phase are well documented in the literature, a 

chemical process that allows the generation of nanoparticle self-assembly through control over the 

compositions and the surface chemistries still remains a challenge. 


Recently, we have developed a new aqueous one-pot process for nano-structured (6 nm in size) hybrid 

Organic/Inorganic TiO2 materials, starting from molecular heteroleptic alkoxides of titanium.2 This method 

offers the convenience and economical advantages of being environmentally friendly (organic-free solvent). 

It also appears to be an efficient and reliable method for a precise control of the organic loadings (up to about 

20% in weight) and for adjusting the combined Organic/Inorganic properties. 

Molecules such as para-amino benzoic acid (PABA) were found to be chemisorbed as a carboxylate onto 

TiO2 nano-particles. Chemical (e.g. pH) and spectroscopic (e.g. FT-IR, Neutron diffusion) data were 

consistent with strong chemisorption of the amino acid molecules onto the TiO2 nanoparticles surface 

through bidentate chelate or bridging coordination. Weight losses between 175 and 500 °C of our 

TiO2/PABA-I to -V samples ranged from about 7 to 21% of organics (TG average weight losses: 6.9, 10.3, 

11.7, 14.8, 20.8 %), and each sample exhibited highly reproducible data as a very interesting feature (TG 

average standard deviation = ± 0.3 %). Other remarkable trends in the physicochemical properties of such 

hybrid nanomaterials were the formation of different three dimensional superstructures by increasing the 

surface organic rate. N2-sorption isotherm patterns of highly functionalized nanomaterials demonstrated an 

extensively interconnected porous network and a so-called “pore-blocking effect”. 

Preliminary results of solar protection evaluation were obtained with 300-μm thick films by using the same 

mass of hybrid nanoparticles. The TiO2/PABA-I sample displayed uniform and grain-free films with low 

intensity of transmitted light. Such a nanomaterial appeared efficient to block out all the UV radiation at sea 

level, and it also seemed promising for cosmetic applications (lowest amount of organic UV filter). The 

aggregation effect, that is, for the TiO2/PABA-V sample, led to inhomogeneous films and to an increase in 

the intensity of transmitted light in the UV-A radiation zone. These results demonstrated that precise control 

of the organic loading was an important parameter for adjusting the performance of nanohybrid titania for 

UVA + UVB sunscreen applications.2b 

125


In an attempt to use NH2– functions as surface sites for further organic reactions, we studied the chemical 

reactivity of our TiO2/PABA nano-structured material through coupling reactions with DTPA dianhydride in 

dry DMF. 

Lanthanum and gadolinium nitrates were chosen in order to check the efficiency of these hybrid nanostructured 

materials toward the selective separation of lanthanides in acidic aqueous solution (to copy 

actinide/lanthanide separation). Amounts of lanthanides (La and Gd) in aqueous solutions were determined 

by ICP-AES spectrometry with a Spectro D (Spectro). Gd3+ and La3+ complexations efficiencies of 50 mg 

of each TiO2/PABA-DTPA-I, -II and -V nano-materials as a function of pH exhibited that only 

TiO2/PABA-DTPA-II gave a unique selectivity (SGd/La > 76) towards Gd3+ in the pH range of 2–5. By 

increasing the organic content using TiO2/PABA-DTPA–V, the maximum capacity increased strongly but 

the selectivity SGd/La decreased to 12.6 from pH 3. These data showed again that the chemical selforganization 

in such hybrid nanostructured materials has a remarkable influence on their physicochemical 

properties.3 

Other applications such as support for liquid phase selective oxidation catalysis4 , drinkable water cleaning 

or as efficient MRI agent will also be addressed in order to demonstrate how control of the surface 

functionality and hence control of the self-assembly process (formed by strongly interacting nanocrystals) 

can considerably affect the final mesoscale physicochemical properties. 


In conclusion, we have described a simple synthetic methodology for hybrid TiO2 nano-materials which 

successfully formed UV sunscreen additives or ionic recognition devices to enable UVA+UVB solar 

protection or selective lanthanides separation, respectively. They provide a better understanding in the 

requirements of self-assembled (-organized) material design for further elaboration of functional nanostructured 

materials. 

References 

1. See review: (a) C. Sanchez, B. Julian, P. Belleville and M. Popall, J. Mater. Chem., 2005, 15, 3559 ; (b) C. Sanchez, G.J. De A.A. Soler-Illia, F. 

Ribot and D. Grosso, C.R. Chimie, 2003, 6, 1131. 

2. (a) S. Daniele, L.G. Hubert-Pfalzgraf, patent WO 2007/017586 A1. (b) Rahal, S. Daniele, L.G. Hubert-Pfalzgraf, V. Guyot-Férreol, J.F. Tranchant, 

Eur. J. Inorg. Chem., 2008, 980. 

3. R. Rahal, S. Daniele, S. Pellet-Rostaing, M. Lemaire, Chem Lett., 2007, 1364. 

4. (a) M. Beyrhouty, S. Daniele, A.B. Sorokin, L.G. Hubert-Pfalzgraf, New J. Chem., 2005, 29, 1245-1248. (b) V. Mendez, V. Caps, S. Daniele, 

Chem Comm., 2009, 3116-3118. 

126


11H20-11H40 

Local structure at substitutional Mn2+ ions in small cubic ZnS nanocrystals 

self-assembled into a mesoporous structure. 

S. V. Nistor*, M. Stefan, L. C. Nistor, D. Ghica, N. J. Barascu and C. D. Mateescu 

(National Institute of Materials Physics, Atomistilor 105bis, POB MG 7, Magurele-Ilfov, 077125 Romania).* 

snistor@infim.ro. 

Due to the high potential of applications based on outstanding optical and photocatalytic properties, cubic 

ZnS nanocrystals activated with transition ions, in particular Mn2+, were between the first investigated II-VI 

semiconductor nanocrystals. Despite intensive research, the Mn2+ impurities localization in the nanocrystals 

core is still unclear. Electron Paramagnetic Resonance (EPR) investigations reported the unexpected 

presence of an axial crystal-field (CF) at the substitutional Zn2+ sites of normal cubic symmetry and a large 

range of values for the associated D-parameter. Determining accurate spectra parameters, essential for 

explaining the origin of a possible non-cubic local CF, requires well resolved EPR spectra, not available in 

the previously investigated nanocrystalline powders. 

We have prepared by a surfactant-assisted liquid-liquid reaction at room temperature a sponge-like 

mesoporous structure self-assembled from nanocrystals of cubic ZnS doped with Mn2+ ions (cZnS:Mn) [1]. 

The resulting tight size distribution around 2 nm of the cZnS:Mn nanocrystals and the improved EPR spectra 

resolution, with the narrowest lines reported so-far, were attributed to the restraining effect of selfassembling 

[2]. The full analysis, with dedicated software, of the EPR spectra recorded at low and high 

microwave frequencies confirmed the presence, besides the cubic parameters also found in cubic ZnS single 

crystals, of an axial CF component described by the parameter |D| = 41x 10-4 cm-1, attributed to the 

localization of the Mn2+ ions in the nanocrystals core next to an extended planar defect, as a stacking fault 

or twin. The proposed local structure is supported by earlier EPR results in strongly defective cZnS single 

crystals [3] and by our High Resolution Transmission Electron Microscopy (HRTEM) study which shows 

that ~ 30% of the investigated cZnS:Mn nanocrystals contain such extended planar defects. 

The improved quality of the cZnS:Mn nanocrystals self-assembled into a mesoporous structure did allow us 

to conclude, based on a correlated EPR and HRTEM investigation, that Mn2+ impurities are preferentially 

localized in the core of the cZnS:Mn nanocrystals at Zn2+ sites situated next to a stacking fault or twin. It 

also suggests that doping of Mn2+ ions in small cZnS:Mn and possibly in other cubic II-VI semiconductor 

nanocrystals is assisted by the extended planar defects. Such an extended lattice defects assisted (ELDA) 

incorporation mechanism can also offer a valid explanation for the high concentration of impurity ions, such 

as Mn2+ or Co2+, observed in cubic II-VI nanocrystals grown at low temperatures. 

[1]. S. V. Nistor, L. C. Nistor, M. Stefan et al. Superlattices and Microstructures 16, 306 (2009). 

[2]. S. V. Nistor, L. C. Nistor, M. Stefan et al. Rom. Rep. Phys. (2010) (in press). 

[3]. M. F. Bulanyi, A. V. Kovalenko and B. A. Polezhaev, J. Appl. Spectr. 69, 747 (2002) and ref. cited therein 

127

Absorbance (a.u.) 

Absorbance (a.u.) 


11H40-12H00 

Fullerenes C60 self-assembled on functionalized surfaces. 

Grégory Delafosse1,2,3, Lionel Patrone1,2,3, Didier Goguenheim1,2,3 (1 Aix-Marseille 

Université, IM2NP; 2 CNRS, IM2NP (UMR 6242); 3 Institut Supérieur de l‟Electronique et du Numérique, IM2NP 

Maison des Technologies, Place Georges Pompidou, F-83000 Toulon, France). gregory.delafosse@im2np.fr 


Memory devices play an important role in electronics market leading to a growing research interest in the 

next generation of non-volatile memory cells. Numerous groups [1,2] work on top-down memory cells based 

on fullerenes C60 that are generally embedded in insulating polymers where they act as storage sites. Beside 

these studies, a reaction path between amines and fullerenes [3] may be used to covalently bind C60 on 

amine-functionalized surfaces. Such an approach is interesting since it involves self-assembled monolayers 

(SAM) [4,5] which constitute a promising strategy to build molecular nano-devices. For applications 

compatible with microelectronics technology, it is very important to control first the formation of amineterminated 

SAMs grafted on silicon, second the grafting of a C60 monolayer on top of these SAMs. In this 

work, we studied these two steps in order to build memory cells using a bottom-up approach based on 

organic SAMs. 


As substrates, we used silicon covered with its native oxide, and Au(111) for scanning tunnelling microscopy 

(STM) experiments. Surface modification is observed by contact angle measurements, ellipsometry, UVvisible 

and FTIR spectroscopy, and AFM/STM microscopy. Surface functionalization is performed using 

aminopropyltrimethoxysilane (APTMS) molecules for Si/SiO2 surfaces, and aminothiophenol or 

aminoethanethiol for Au(111). We developed two methods to build APTMS SAMs on Si/SiO2 substrates. 

Using APTMS in methanol solution, SAM formation was analyzed in order to obtain the right parameters 

leading to a single amine-functionalized monolayer. A second original way was studied using a dry 

deposition method. In the latest, freshly prepared clean substrates are exposed to APTMS vapor under a 

nitrogen flux, leading to the formation of APTMS SAM. This deposition method allowed us to show there is 

a minimum waiting time of ~4 hours under our conditions for the monolayer to be grafted on Si/SiO2. 

APTMS SAM formation could be monitored using ATR-FTIR spectroscopy. 

3253 

3minutes 

38minutes 

90minutes 

130minutes 

150minutes 

180minutes 

214minutes 

240minutes 

270minutes 

300minutes 

330minutes 

365minutes 

2927 

2857 

3minutes 

38minutes 

90minutes 

130minutes 

150minutes 

180minutes 

214minutes 

240minutes 

270minutes 

300minutes 

330minutes 

365minutes 

3500 3000 

Wavenumber (cm -1 ) 

3000 2950 2900 2850 2800 2750 2700 

Wavenumber (cm -1 ) 

(a) 

Figure 1. ATR-FTIR spectra of dry-deposited APTMS SAM showing (a) the increase of OH absorption band, (b) CH2 band narrowing with time. 

(b) 

128


Particularly, the increase of OH absorption band at ~3253 cm-1 (Fig.1(a)) may be attributed to the formation 

of methanol due to the reaction between methoxysilane heads and silicon oxide. Moreover CH2 band 

narrowing (Fig.1(b)) indicates the monolayer order is increasing during the grafting process. Fullerenes are 

then grafted from a toluene solution on these amine-functionalized SAMs. Two deposition conditions are 

compared: at room temperature and at high temperature under solvent reflux. AFM/STM experiments 

allowed monitoring fullerene deposition by either imaging (Fig.2) or I-V characteristics (Fig.3). 

Figure 2. STM (100nmx100nm) image of 

C 60 molecules grafted under reflux during 

24 hours on NH 2 (aminoethanethiol) 

functionalized Au(111). 

Figure 3. STM I-V characteristic of C 60 molecules 

grafted under reflux during 24 hours on NH 2 

(aminoethanethiol) functionalized Au(111). 


Further studies are addressed such as thermal deposition of fullerenes [6], Surface Enhanced Raman 

Scattering on fullerenes grafted on nanostructured amine-modified gold substrates, and electronic transport 

properties (elctron trapping for memory cell application,…) of those C60 SAMs via evaporated metallic 

contacts. 

Acknowledgments 

Equipment used for this study was mainly funded by the “Objectif 2” EEC program (FEDER), the “Conseil 

Général du Var” Council, the PACA Regional Council and Toulon Provence Méditerranée which are 

acknowledged. 

References: 

1. A. Kanwal, M. Chowalla, Appl. Phys. Lett. 89, 203103 (2006) 

2. H.S. Majumdar, J.K. Baral, R. Osterbacka, O. Ikkala, H. Stubb, Organic Electronics 6, 188 (2005) 

3. G.P. Miller, Comptes-Rendus Chimie 9, 952 (2006) 

4. A. Ulman, Chem. Rev. 96, 1533(1996) 

5. F. Schreiber, Progress in Surf. Sci. 65, 151 (2000) 

6. T.H. Hou, U. Ganguly, E.C. Kan, Appl. Phys. Lett. 89, 253113 (2006) 

129


12H00-12H20 

Modified Langmuir-Blodgett deposition of nanoparticles for preparation of 

large area ordered 2D and (2+1)D arrays. 

L. Chitu1, P. Siffalovic1, E. Majkova1, M. Jergel1, S. Luby1, I. Capek2, A. Satka3, 

S. V. Roth4, A. Timmann4, J. Keckes5 and G. Maier6 (1Institute of Physics, Slovak Academy 

of Science, Dubravska cesta 9, 84511 Bratislava, Slovakia, 2Polymer Institute Slovak Academy of Science, 

Dubravska cesta 9, 84236 Bratislava, Slovakia, 3International Laser Center and Faculty of Electrical Engineering 

and Informatics SUT, 81219 Bratislava, Slovakia, 4HASYLAB /DESY, Notkestr. 86, 22603 Hamburg, Germany, 

5Erich Schmid Institute for Materials Science, Austrian Academy of Sciences, Jahnstrasse 12, A-8700 Leoben 

,Austria, 6Materials Center Leoben Forschung GmbH, Roseggerstraße 12, A-8700 Leoben, 

Austria).fyzichil@savba.sk, Peter.Siffalovic@savba.sk, majkova@savba.sk, Matej.Jergel@savba.sk, 

Stefan.Luby@savba.sk, Ignac.Capek@savba.sk, alexander.satka@stuba.sk, stephan.roth@desy.de, 

jozef.keckes@mu-leoben.at, Guenther.Maier@mcl.at 


The production of ordered nanoparticle arrays over macroscopic areas is of crucial importance for the 

integration into commercial devices. For preparation of ordered nanoparticle monolayers, the Langmuir- 

Blodgett method is often used. In this study, we present the formation of ordered 2D (monolayers) and 

(2+1)D (periodic multilayer with vertically disorderd nanoparticles) nanoparticle arrays over the large areas 

using a modified LB technique. For the deposition, the iron oxide nanoparticles were used [1]. The lateral 

ordering and homogeneity of the arrays was studied by SEM, scanning grazing incidence small angle X-ray 

scattering (GISAXS) and X-ray reflectivity techniques. 


In the modified LB deposition method, developed in our laboratory, the nanoparticle monolayer is formed on 

the water surface by compression and subsequently it is transferred onto the substrate by a controlled 

removal of the water subphase. In this way ordered 2D arrays of iron oxide nanoparticles distributed over the 

large areas (tens of cm) were prepared. Scanning GISAXS showed the formation of an ordered and uniform 

nanoparticle monolayer over the large area (20 cm2) which was confirmed by X-ray reflectivity. The SEM 

showed the typical “mosaic” structure of the nanoparticle monolayer [2]. The modified LB technique was 

used also for preparation of the (2+1) ordered arrays (multilayers) over large areas. The distinct Bragg 

reflection peaks observed in the X-ray reflectivity curves confirmed the formation of a vertically periodic 

layered structure. The SEM pictures showed a similar ordering of nanoparticles in the top layer as it was 

observed for the monolayer. The GISAXS analysis indicated the absence of the vertical correlation of the 

nanoparticle positions in the multilayer. The results on preparation of the nanoparticle multilayers correlated 

also vertically using the UV radiation during the LB deposition and thermal treatment on already deposited 

samples will be presented too. 


Using the modified LB technique, the ordered 2D and (2+1)D arrays of iron oxide nanoparticles were 

prepared over the large areas (tens of cm2). The SEM, XRR and scanning GISAXS proved the uniformity 

and ordering of the 2D arrays. The nanoparticle multilayers showed the well defined layering, however, the 

position of nanoparticles in the multilayer is not vertically correlated. The effect of UV irradiation during the 

LB deposition and/or of the post deposition heat treatment on the vertical correlation is presented. 

References: 

1. P. Siffalovic, E. Majkova, L. Chitu, M. Jergel, S. Luby, A. Satka and S. V. Roth, Phys. Rev: B, 76 195432- A1 (2007) 

2. L. Chitu, M. Jergel E. Majkova, S. Luby, I. Capek, A. Satka, J.Ivan, J. Kovac, and M. Timko, Mater. Sci. Eng., C 27, 1415, 2007 

130


Room Port-Pin 

9H00-9H30 

Improving photovoltaic response of CNTs/Si heterojunctions using different 

carbon nanotubes types and CNTs film thicknesses. 

P. Castrucci1, S. Del Gobbo1, L. Camilli1, M. Scarselli1, S. Casciardi2, F. 

Tombolini2, M. De Crescenzi1 (1Dipartimento di Fisica and Unità CNISM, Università di Roma Tor 

Vergata Via della Ricerca Scientifica 1, I-00133 Roma, Italy; 2 Dipartimento di Igiene del Lavoro, ISPESL, I-00040 

Monte Porzio Catone, Italy). paola.castrucci@roma2.infn.it, silvano.delgobbo@roma2.infn.it, 

manuela.scarselli@roma2.infn.it, luca.camilli@roma2.infn.it, maurizio.decrescenzi@roma2.infn.it, 

stefano.casciardi@ispesl.it , francesca.tombolini@ispesl.it 


In the last years, carbon nanotubes (CNTs) have been considered a great promise in the development of highefficiency 

solar cells, due to their excellent transport and electronic properties. Use of nanotubes in this area 

has been primarily focussed on hybrid structures based on conjugated polymers giving rise to cells 

characterized by modest efficiency and low environmental stability. 1,2 Recently the investigation of the 

CNTs/silicon heterostructure paved the way for developing solar cells with moderate efficiency, good 

stability and reduced cost, by integrating nano- and silicon technologies. 3-5 Nanotubes dispersed or grown 

on silicon substrate are fundamental for separation, transport and collection of charges which have been 

mostly generated in the silicon underneath. In this scenario, the thickness of the nanotubes film is a crucial 

point to improve the efficiency of the solar cell as well as the number of the walls forming the CNTs. 


In this work, we report recent studies on the efficiency of CNTs/silicon heterojunctions pointing our 

attention on CNTs film thickness and nanotubes nature. We grew nanotubes directly on the silicon substrate 

by chemical vapour deposition in acetylene atmosphere at T = 780 °C. Iron catalyst has been pre-deposited 

on the bare Si surface at room temperature. A set of samples has been obtained by varying the nominal 

thickness of the iron catalyst. We found that the structure of the grown tubes and to the morphology of the 

CNTs film is directly connected to the dimension of the catalyst nanoparticles. Incident photon conversion 

efficiency (IPCE) and power conversion efficiency have been measured by electrically contacting the 

nanotubes film with silver paint and using an optical set-up made of a Xenon lamp equipped with a 

monochromator, focusing and collecting optics and a) a reflecting light chopper and lock-in amplifier and b) 

a Keithley 2602A sourcemeter, respectively. Scanning electron microscopy and transmission electronic 

microscopy have been performed to measure the thickness of the nanotubes film and the CNTs size. We 

observed that there exists an optimal thickness of the nanotubes film, for which nanotubes film behaves as an 

almost transparent electrode for silicon illumination and at the same time forms the highest number of 

heterojunctions to separate and transport charges. On the other hand, the number of CNT walls contributes to 

establish the metallic or semiconducting character of the film and its work function, so contributing to the 

intensity of the collected photocurrent. In best case, we obtained an IPCE of 9% for a catalyst iron thickness 

of 0.1nm. 


In conclusion we report a study on the connection between the nominal thickness of the iron catalyst film 

deposited to grow carbon nanotubes and (i) their diameter and number of walls, (ii) the morphology and 

131


thickness of the CNTs resulting film. Besides, we show that these two parameters are fundamental to tune 

the photoconversion efficiency of CNTs/Si heterostructures. 

References 

1) E. Kymakis, G. A. J. Amaratunga, Appl. Phys. Lett. 80 (2002) 112. 

2) J. Arranz-Andres, W. J. Blau, Carbon, 46 (2008) 2067. 

3) Y. Jia, J. Wei, K. Wang, A. Cao, Q. Shu, X. Gui, Y. Zhu, D. Zhuang, G. Zhang, B. Ma, L. Wang, W. Liu, Z. Wang, J. Luo, D. Wu, Adv. 

Mater. 20 (2008) 4594. 

4) Z. Li, V. P. Kunets, V. Saini, Y. Xu, E. Dervishi, G. J. Salamo, A. R. Biris, A. S. Biris, ACSNano, 3 (2009) 1407 

5) P. Castrucci, C.Scilletta, S. Del Gobbo, M. Scarselli, M. Simeoni, B. Delley, A. Continenza and M. De Crescenzi, to be published 

9H30-9H50 

Many Body Shake Up in Core-Valence-Valence Electron Emission from Single 

Wall Carbon Nanotubes. 

A. Sindona, M. Pisarra, A. Bonanno, A. Cupolillo, P. Riccardi, G. Falcone 

(DIPARTIMENTO DI FISICA, UNIVERSITA‟ DELLA CALABRIA and INFN, Gruppo Collegato di COSENZA, 

VIA P: BUCCI, CUBO 31C, 87036 RENDE (CS), ITALY). antonello.sindona@fis.unical.it; 

michelepisarra@yahoo.it 

1 – Introduction. 

Fig. 1: Experimental derivative of the Kinetic energy distribution of 

electrons ejected from bundles of SWNCTs via Auger CVV (circles); 

corrected distribution after Shirley background subtraction (dots); 

theoretical distribution calculated from the model presented here 

(continuous line). 

Auger processes are of crucial importance in 

understanding the electronic properties of both 

solid state and biological samples. In materials 

with a band structure, the creation of a core-hole 

lead to core-valence-valence (CVV) Auger 

electron emission, where the initially empty core 

level causes a decay that involves two valence 

electrons: one neutralizing the core-hole and the 

other being ejected [1,2]. A fundamental role is 

played by the broadening of the Auger peak that 

contains information on a variety of effects, such 

as the finite lifetime of initial and final states, the 

electron-phonon interaction, and the many-body 

shake up of Fermi electrons, which are spectator to 

the CVV transition [3,4]. Some attempts have been 

made to apply these concepts in interpreting the 

Auger spectra of Carbon based and Carbon 

nanostructured materials, although ad adequate 

picture is still lacking [5]. In this paper, we present 

a tight-binding model to calculate the CVV spectra 

from an ideal sheet of Graphene and a cylindrical 

Carbon NanoTube (CNT). 

2 – Model and Application. 

The Hamiltonian of a CVV process, in a CNT of specific diameter and chirality, has an unperturbed 

bands and (iii) the core-hole. The perturbation V is modeled by a two-body operator, in which the (screened) 

132


electron-electron repulsion is approximated by the simple Yukawa potential. The key-quantity in our study is 

the differential cross- 

of H0, with the corestate 

empty, to a final state with the core-state occupied and an ejected electron of kinetic energy E, within 

H0 and V is treated as a small perturbation. The tight-binding (TB) calculational scheme allows to select 

only CVV processes in which either the neutralizing or the ejected electrons, in the initial state, lie within 

nearest neighbor atomic sites to the core-hole site. Many-body corrections, outside the Fermi's golden rule, 

are included in a broadening function B(E) containing: (a) a Lorentian component to cope with lifetime 

effects, (b) a Gaussian function to account for the electron-phonon interaction and (c) an asymmetric 

broadening function, describing the electron shake-up. The kinetic energy distribution of ejected electrons, 

are taken from literature. Measurements of CVV electron emissions from bundles of Single Wall CNTs are 

correctly reproduced by averaging N(E) over a statistical mixture of tubes, whose diameters are in the range 

of commercial Bucky papers (Fig. 1). 

3 – Conclusion. 

We used a tight-binding procedure to calculate CVV spectra of electron emitted from ideal CNTs; manybody 

electron correlations have been included in a broadening function whose asymmetric component is to 

be ascribed to the non negligible role of shake-up electrons. This result has confirmed the validity of the 

analysis proposed in Ref.[3], where shake-up effects have been isolated in ion-induced Auger electron 

emission from Aluminum and in X-ray photoemission spectra from CNTs . 

References 

[1] J.J. Lander, Phys. Rev. 91 (1953) 1382; H.D. Hagstrum, Inelastic Ion-Surface Collisions, (Ac.Press, NY, 1977), 1. 

[2] C.-O. Almbladh, A. L. Morales, and G. Grossmann, Phys. Rev. B 39 (1989), 3489; C.-O. Almbladh and A. L. Morales, ibid. 39 (1989), 

3503; C.-M. Liegener, Phys. Rev. B 43, 7561 (1991); M. Cini, Solid State Commun. 24 (1977), 681; Phys. Rev. B 17 (1978), 2788. 

[3] A. Sindona, R.A. Baragiola, G. Falcone, A. Oliva, P. Riccardi, Phys. Rev. A 71, 052903 (2005); A. Sindona, S.A. Rudi, S. Maletta, R.A. 

Baragiola, G. Falcone, P. Riccardi, Surf. Sci. 601, 1205 (2007); A. Sindona, F. Plastina, A. Cupolillo, C. Giallombardo, G. Falcone and L. Papagno, 

Surf. Sci., 601, 2805 (2007). 

[4] G.D. Mahan, Phys. Rev. 163, 612 (1967); P. Nozieres and C.T. De Dominicis, Phys. Rev. 178, 1097 (1969); K. Othaka and Y. Tanabe, 

Rev. Mod. Phys. 62, 929 (1990). 

[5] E. Perfetto et al., Phys Rev B 76, 233408 (2007). 

9H50-10H10 

High photoconductivity in carbon nanotube sheets. 

V. Grossi, S. Santucci and M. Passacantando (Dipartimento di Fisica, Università degli Studi 

dell'Aquila, Via Vetoio 10, I-67100 Coppito (L'Aquila), Italy). valentina.grossi@aquila.infn.it, 

sandro.santucci@aquila.infn.it, maurizio.passacantando@aquila.infn.it 


Photocurrent measurements derived by light excitation have been reported in different configurations 

exploiting carbon nanotubes (CNTs) [1]. Photoresponse in macro-bundles of multi-walled carbon nanotubes 

(MWCNTs) has been recently observed [2], and a technologically promising high photon-to-current 

conversion has been demonstrated for MWCNTs by means of an electrochemical method [3]. Studies on 

large area sheets of MWCNTs grown on sapphire substrate [4] using also pulsed laser beams [5] may 

provide us opportunities for constructing smart structures with multiple functionalities. 


133


CNTs have been synthesised at 750 °C by thermal chemical vapour deposition (CVD) of acetylene (C2H2) 

gas, in ammonia (NH3) atmosphere, onto SiO2/Si(100) substrates with nickel (Ni) catalyst nanoparticles. A 

Ni thin film (3 nm) has been deposited by thermal evaporation onto a masked substrates (100 nm of SiO2 

grown onto a silicon (100) wafer) in order to obtain four single rectangular Ni strips of different length. 

CNTs are grown only onto the Ni strips. Gold rectangular electrodes have been evaporated on the ends of 

each strip overlapping the nanotubes for about 1 mm. 

This device has been used in order to investigate the photoconductivity properties of MWCNTs under white 

light and different radiation in the visible region. It has been observed that the dark current versus bias 

voltage characteristics of each strip have an Ohmic behaviour, and the presence of continuous white light 

illumination, as well as monochromatic radiation, induces a photocurrent in each strip. The photocurrent has 

been generated by illuminating either the whole device surface with white light or a small part of the CNT 

strips with a laser spot. We have obtained a current of few mA in a narrow range of bias voltages -1


absorption and thus harvesting solar energy [1]. Investigations on the photo-electrochemical properties of 

single wall carbon nanotubes (SWCNTs) were carried out and the photon-to-photocurrent efficiency (IPCE) 

[2] reported remained low (about 0.15%) due to the rapid exciton annihilation [2]. For this reason a number 

of strategies were developed to enhance the photoconversion efficiency for SWCNTs. In this research field, 

of equal interest are multi-wall carbon nanotubes (MWCNTs), in which the presence of numerous concentric 

cylindrical walls provides additional pathways for the flow of photogenerated charge carriers. We have 

already demonstrated that MWCNTs can generate photocurrent in the visible and ultraviolet spectral range 

[3] and the maximum IPCE reported was approximately 7%, about 50 times higher than that of SWCNTs 

[2]. In addition, we also observed that a sizeable enhancement in the photocurrent generation can be obtained 

in MWCNTs decorated with Cu-metal clusters deposited by thermal evaporation [4]. 


In this work we show recent studies on the influence on the photocurrent response from Cu-MWCNTs as a 

function of the Cu clusters size and morphology. 

The Cu deposition produced crystalline nanoparticles localized on the outer walls of the CNTs. The mean 

dimension of the Cu nanoparticles depends on the quantity of deposited copper. The photocurrent response 

of the different sized hybrid samples (Cu-MWCNTS) was measured with a three-arm photo-electrochemical 

cell. It was found that a sizeable enhancement in the photocurrent over the visible and near ultraviolet energy 

range can be obtained. The IPCE increased for different sized-CuMWCNTs with respect to that of bare 

MWCNTs up to 0.5 nm Cu nominal thickness. The maximum in the IPCE obtained at 0.2nm Cu nominal 

thickness was 13% while that from bare MWCNTs was about 5.4%. Nevertheless, for Cu nominal 

depositions greater than 1nm the effect reversed and the IPCE from Cu-MWCNTs system started decreasing 

with respect to that of MWCNTs. 

The presence of a photocurrent signal is a clear-cut indication that MWCNTs act as photoconductive 

material. This property is essential for the conversion of light into electricity as upon illumination a fast 

charge separation and a slow charge recombination is required. In charge-separated species lifetimes of the 

order of microseconds have been evaluated in photocurrent generation in SWCNTs. Longer lifetimes are 

expected for MWCNTs than for SWCNTs, due to a enhanced delocalization and percolation of the electrons 

inside the concentric tubes which decelerate the recombination‟s decay dynamics. 

Copper is known to be a good electron donor upon photo excitation. Therefore, the photocurrent signal 

enhancement indicates that additional electrons coming from the Cu nano-particles are efficiently transferred 

to the numerous concentric cylindrical walls of carbon nanotubes which offer more pathways for the flow of 

photogenerated charge carriers. 


The results presented in this study point out two major findings: (i) the ability of Cu nano-particles to 

significantly modify the electronic properties of the entire hybrid system facilitating the charge separation 

and subsequent collection at the electrode (ii) the ability to tune the photoelectrochemical response and 

photoconversion efficiency of MWCNTs via size control of Cu nanoparticles. The maximum powerconversion 

efficiency obtained with Cu-MWCNTs film highlights the usefulness of tubular morphology in 

facilitating charge transPort-Pin nanostructure-based solar cells. 

It was found that the photoactive Cu nano-particles greatly enhanced the intrinsic ability of MWCNTs to 

behave as an efficient low dimensional media for generating e-h carriers. The reported hybrid system seems 

to be as promising as that obtained from CNTs functionalization with organic molecules. 

135


[1] Carbon nanotubes, Acc. Chem. Res. 35 (2002) 997. 

[2] S. Barazzouk, S. Hotchandani, K. Vinodgopal, P.V. Kamat, J. Phys. Chem. B 108, 17015 (2004) 

[3] P. Castrucci, F. Tombolini, M. Scarselli, E. Speiser, S. Del Gobbo, W. Richter, M. De Crescenzi, M. Diociaiuti, E. Gatto, M. Venanzi, Appl. Phys. 

Lett. 89, 253107 (2006) 

[4] M. Scarselli, C. Scilletta, F. Tombolini, P. Castrucci, M. Diociaiuti, S. Casciardi, E. Gatto M. Venanzi, M. De Crescenzi, J. Phys. Chem C 113, 

5860 (2009) 

11H00-11H20 

Carbon nanotube based composites: electrical and mechanical properties. 

BELLUCCI (INFN – LNF, via E. Fermi, 40, 00044 Frascati (RM) Italy). bellucci@lnf.infn.it 

We report on the results of a systematic study of the electrical properties of carbon nanotube-based 

polymeric composite materials. Our purpose is the production and characterization of a light, thin and 

mechanically strong new composite material able to cover electric circuits against external electromagnetic 

interference. Setting the resistivity properties of carbon nanotube-based composites against those containing 

micro-sized graphite particles as constituent we show the advantages of using carbon nanotubes. The change 

in the resistivity values for carbon nanotubes-based composites turns out to be significant, even for small 

changes in the added carbon nanotubes percentage [1,2,3]. Mechanical characterizations of the 

nanocomposites will be also discussed. The study of mechanical performances is carried out focusing on the 

influence on the mechanical properties of different parameters, such as [4,5]: 

• Aspect ratio (defining the matrix-CNTs interface extension); 

• CNTs chemical functionalization; 

• Synthesis method. 

The analysis carried out on the mechanical properties of nanocomposites shows interesting results: 

The existence of a “rheological percolation threshold” for some of the different CNTs, below which there 

seems to be a good dispersion, whereas above which, there seems to be a better dispersion of the 

agglomerates themselves. 

Accordingly, the ineffectiveness of the functionalization with organic polar groups, when the CNT 

dispersion does not reach a reasonable level. 

In spite of the industrial advantage of commercial CNTs (e.g. produced in bulk quantities, large area 

deposition), those obtained through arc discharge yield the highest strength improvement. 

The analysis carried out on the electrical properties of nanocomposites also shows interesting results : 

For all concentrations considered, CNTs show improved conducting properties, with respect to carbon black. 

At low CNT concentrations the lower defect density seems to prevail over the aspect ratio. 

As the CNT concentration is increased, the conductivity for SWNTs shows a sudden rise Þ the percolation 

threshold has been crossed. 

[1] S. Bellucci, et al. 2006 Nanotech 2006 Vol. 1, p. 129-133, ISBN 0-9767985-6-5 

[2] S. Bellucci, et al. J Exp Nanosci, 2-3, (2007) 

[3] S. Bellucci, F. Micciulla, N. Pugno, The Nanomechanics in Italy, 2007: 197-210 ISBN: 978-81-308-0237-4, Ed.: N. Pugno, Research Signpost, 

Kerala, India, p. 197-210. 

[4] S. Bellucci, Carbon nanotubes composites for aerospace applications, submitted to Journal of Nanostructured Polymers and Nanocomposites 

[5] S. Bellucci, et al., Screening Electromagnetic Interference Effect using Nanocomposites, Macromolecular Symposia. vol. 263, pp. 21-29 ISSN: 

1022 1360, 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 

136


11H20-11H40 

Ordered growth of multi-walled nanotubes on Ge nanocrystals. 

A. Capasso1, E. Waclawik1, J. M. Bell1, S. Ruffell2, A. Sgarlata3, M. Scarselli3, M. 

De Crescenzi3 and N. Motta1 (1Queensland University of Technology, Brisbane, Australia; 2Australian 

National University, Canberra, Australia; 3 University of Rome “Tor Vergata”, Rome, Italy). 


Role of catalyst in carbon nanotubes (CNTs) synthesis is still under debate. In the past, transition metals have 

been regarded as essential for carbon diffusion and subsequent nucleation of a graphitic tube-like structure. 

Recent studies however show that particles of many other materials (metallic and semiconducting) could 

fulfill this task, provided their size falls in the nanometer range. Semiconductor nanoparticles can decompose 

the carbon gas source and thus result very active as catalyst in the nanotube synthesis. Ge nanocrystals in 

particular have a much lower melting point compared to bulk: carbon can then diffuse inside the crystal and 

allow the nucleation of a nanotube once the super-saturation regime is reached. 

2 – Experimental details 

In the present paper, we report a synthesis of CNTs on Si surfaces by using Ge as catalyst. The Si substrates 

have been pre-patterned by nanoindentation, creating a grid of micro indents. Ge evaporation in ultra-high 

vacuum leads to the formation of small Ge nanoparticles, which result ordered on the patterns. CNTs are 

then grown by low-pressure chemical vapor deposition of acetylene. Multi walled nanotubes arise from Ge 

nanoparticles in small bundles all over the surface, whereas on patterned areas a more limited yet quite 

ordered growth occurs nearby the indents. The samples are imaged by Field Emission-SEM and AFM. EDX 

elemental analysis and Raman spectroscopy provide further evidence of the metal-free nature of this 

synthesis. 


Our results confirm that it is possible to grow CNTs without the use of any metal catalyst. By means of 

surface nanoindentation, Ge nanocrystals can be assembled in controlled position and then employed as 

seeds for the tube nucleation. This approach could be viable for integrating pure CNTs in specific sites on a 

semiconductor, opening a way for the conception of enhanced electronic devices. 

11H40-12H00 

Boron Nanotubes and its properties: semiempirical investigations. 

Zaporotskova I.V., Perevalova E.V., Zaporotskova N.P (Volgograd State University, 

Volgograd, 400062, Universitetskii prospect, 100, Russia). 

The problem of formation possibility nanotubular structures is actively discussed now. We considered the 

fragments of single-wall boron nanotubes (n,n) (n=4,5,6,9,11,12). Calculations were carried out by IB-CCC 

method [1]. The analysis of band-gap showed that all of them are semiconductors. Energy of deformation 

decreases with increase of the diameter of B-tubes (n, n). We considered the B-nanotubes (n,0) 

(n=4,5,6,8,12). In this case deformation energy is increases with increase of the diameter of tubes (n,0). 

Calculations of boron tube (6, 6) which contained various defects of structure were obtained by the 

semiempirical MNDO scheme. We research substitution imperfection of B atom by atom C, ions С+ , С-. 

137


We found out substitution energy of defects and its energy level. We studied the B-tube with hole and 

determined the energy of defect activation and the relative portion of vacancies. 

At the moment active search of new surface structures capable of effective adsorption of different gases is 

being carried out. We have investigated an binding opportunity between the H, F, O, Cl atoms and the outer 

surface of B-nanotube (6,6) and have studied the mechanism of this process. The calculations are carried out 

with the use of quantum chemical MNDO scheme. Regular hydrogenation of boron nanotubes was 

investigated. We can confirm that generation of gas-phase hydrogen composite materials based on boron 

nanotube is possible. 

[1] Litinsky A.O., Lebedev N.G., Zaporotskova I.V. Jurnal phyzicheskoi himii. 69. № 1, 189 (1995). 

12H00-12H20 

Epitaxial growth and magnetic properties of Mn5Ge3 compound on Ge(111) 

A. Spiesser1, A. Watanabe2, S.F. Olive-Mendez, M.-T. Dau1, L.A. Michez1, S. 

Nozaki2, A. Glachant1, V. Le Thanh1 ( 1 Centre Interdisciplinaire de 

Nanoscience de Marseille (CINaM-CNRS), Aix-Marseille Université, 

Campus de Luminy, case 913, 13288 Marseille, France 2 Department of 

Electronic Engineering, the University of Electro-Communications, 1-5-1 

Chofugaoka, Chofu-shi, Tokyo 182-8585, Japan) 


The emerging field of spintronics, which is regarded as next-generation electronics, would be 

dramatically boosted if room-temperature ferromagnetism could be added to semiconductor devices and 

integrated circuits that are compatible with silicon CMOS technology. Among numerous approaches such as 

growth of Ge1-xMnx diluted magnetic semiconductors or using spin injection from a transition metal across 

a thin oxide barrier layer, the synthesis of Mn5Ge3/Ge heterostructures is of particular interest since 

Mn5Ge3 is intermetallic and ferromagnetic up to room temperature. Achieving a high-quality epitaxial 

Mn5Ge3 film on Ge not only allows a direct and high efficient injection of spin by tunnel effect through the 

Schottky barrier but also offers a direct route to be integrated into group-IV semiconductors. 


Epitaxial growth of Mn5Ge3/Ge(111) have been investigated by combining structural characterizations via 

reflection high-energy electron diffraction (RHEED), transmission electronic microscopy (TEM) and 

magnetic characterizations using vibrating sample magnetometer (VSM), superconducting quantum 

interference device (SQUID) magnetometers. It is shown that despite a misfit as high as 3.7% between 

Mn5Ge3 and Ge(111), high quality Mn5Ge3 films with an atomically smooth interface can be obtained. 

However, no pseudomorphic growth was observed as in covalent heteroepitaxial systems, Mn5Ge3 films 

were found to be fully strain relieved even after the deposition of a monolayer thick film. We have also 

investigated the effect of the film thickness on the structural and magnetic properties of Mn5Ge3 films. For 

films whose thickness is smaller than 50 nm, the easy axis of magnetization lies in the layers and the hard 

axis is perpendicular to the sample surface. When the film thickness increases, the coercive field becomes 

progressively smaller and the easy axis of magnetization is found to get out of the hexagonal basal (001) plan 

138


but never becomes perpendicular to the sample surface as being expected for bulk materials. The electrical 

measurements have been carried out on Mn5Ge3/Ge(111) diodes, and the I-V characteristics confirm the 

Schottky contacts. The barrier heights, which have never been reported for Mn5Ge3/Ge, are sufficient for 

spin injection. 


Epitaxial Mn5Ge3 films appear to be a unique candidate for spin injection into group IV semiconductors. In 

the form of thin films, it is found that Mn5Ge3 is the most stable phase which can be stabilized while in bulk 

materials the most stable phase is the anti-ferromagnetic Mn11Ge8. Of particular interest, epitaxial films 

with a thickness as high as 180 nm can be obtained, the interface is atomically smooth while the density of 

threading dislocations remains relatively low. This feature will be discussed in terms of the formation of 

intermediate phases at the interface and/or the nature of the interface bonding. 

139

140

We would like to thank our Sponsors : 

141

book of abstracts - IM2NP

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?