Third Day Poster Session, 17 June 2010 - NanoTR-VI

Poster Session, Thursday, June 17
Theme F686 - N1123
Electrical Force Microscopy and SKPM Investigations of Pb Doped CdS Films
S.A. Klimova 1 , M. Arslan 2 *, S.V. Stetsyura 1 , M. Yavuz 2 , E.G. Glukhovskoy 1 , S.B. Venig 1 , Y. Elerman 2
1 University of Saratov State, Department of Nano- and Biomedical Technology, 410012, Saratov, Russia
2University of Ankara, Department of Engineering Physics, Faculty of Engineering, 06100 Besevler, Ankara, Turkey
Abstract- The major focus of this work has been to observe structural and electrical properties of Pb doped CdS films. pH
values of sub-phase can change the crystal structure. Furthermore, we found that surface potential values of these films
depended on pH changing.
Scanning probe microscopy methods allow the
investigation of a variety of sample surface properties
on a nanometer scale. As molecular electronics
advance, the characterization of electrical properties
becomes more and more important [1].
In this study, the structural properties of
monolayers with Pb inclusions which were deposited
on glass with Langmuir-Schaeffer method, were
observed by using SEM (Fig.1, 2) and AFM. In
additionally the electrostatic properties of films were
investigated in EFM and SKPM.
Due to the localization of electrons in the polymer
chain, changing the crystalline structure. It means that
crystal forms of Pb are sensitive to pH changes. As it
can be seen from Figs. 1 and 2, the structure of the LB
film is significantly altered by the changes of the pH
sub-phase. Clusters are received when pH of the water
sub-phase is 8 and the dendrites when 3. Variations of
pH are carry out for control of the surface of the
material CdS. Metal ions diffuse forward into the
surface of CdS by annealing process with different
temperature.
Figure 1. (a) SEM image, and (b) hypermapping image of
dendrite
Figure 3. AFM image (a) 2D (b) 3D
for dendrite structure
(pH: 3.0)
Figure 4. AFM image (a) 2D (b)
3D for cluster structure
(pH: 8.0)
For these films, surface potential (ΔV) values vary
from 0.35 V at pH 3.0 to 0. .07 V at pH 8.0. This
decrease is due to the ionization of the monolayer at
the air/aqueous interface. Therefore, the pH has a
substantial influence on the stability of the films.
In conclusion, for CdS with Pb Langmuir-
and their electrical
Blodgett thin films, grain size
properties effected by sub-phase either acidic medium
or basic medium [2].
* melike.arslan05@gmail.com
[1] Macromol.Rapid Commun. 30, 1167–1178 (2009)
[2] Thin Solid Films 327–329, 56–59 (1998)
Figure 2. (a) SEM image, and (b) hypermapping image of
cluster
In SEM images, Pb accumulations observed on the
surface of films. According to AFM images, the
height of the deposited pattern is about 1 μm for
dendrites (Fig. 3) and 0.5 μm for clusters (Fig. 4). For
dendrite structure, large grains weree formed on top of
glass.
6th Nanoscience and Nanotechnology Conference, zmir, 2010 656