PHYS Ashutosh Rath - Homi Bhabha National Institute

More documents

Recommendations

Info

3.1 As deposited MBE sample showing (a) gold nanostructures with typical size of about ∼ 24 nm (b) SAD pattern showing reflections of both Si and Au and corresponding (c) high resolution image of one of the islands which is showing the d-spacing of Au(111). [127]. . . . . . . . 42 3.2 Bright field transmission electron micrographs depicting real time morphological changes during the in-situ heating. (a), (b), (c), (d), (e), (f), (g), (h) and (i) show the morphology at 200 o C, 300 o C, 325 o C, 350 o C, 363 o C, 400 o C, 510 o C, 600 o C and 700 o C, respectively. With increasing temperature, growth of rectangular nanostructures can be seen [127]. 43 3.3 In-situ SAD patterns taken at various temperatures during heating of 2.0 nm Au/Si(100) system. (a), (b), (c), (d), (e) and (f) show the real-time diffraction pattern at 325 o C, 350 o C, 363 o C, 510 o C, 600 o C and 700 o C respectively [127]. . . . . . . . . . . . . . . . . . . . . . . . . . 45 3.4 (a) Bright field image taken at room temperature after the sample was heated up to 700 o C, (b)selected area diffraction showing the presence of mixed phase of silicide and (c) high resolution transmission electron micrograph of single nano rectangles.[127] . . . . . . . . . . . . . . . 47 3.5 (a) Showing as-deposited thermally grown nanostructures 5 nm Au/ SiO 2 /Si(100) system, (b) corresponding SAD pattern showing the reflection of Au and Silicon, (c) BF transmission electron micrograph at 850 o C and (d) corresponding selected area diffraction pattern [127]. . 49 3.6 (a) STEM− HAADF image on one of gold silicide structure. This shows formation of a hole like structure: (b) the elemental mapping formed with Au x-ray signals, (c) with Si x-ray signals in the STEM- XEDS mode [127]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 3.7 (a) STEM−HAADF image on one of larger gold silicide structure. This shows formation of many holes like structures inside (b) the TEM bright field image of same structure that was shown in (a)[127]. . . . 52 3.8 The lattice image taken from the area shown with circles in figure 3.7(b)[127]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 4.1 (a) SEM image of as-deposited samples of 5 nm Au/SiO 2 /Si(100) (b) SEM image taken at RT after annealed upto 975 o C (c) corresponding bright field TEM image (inset figure shows the HRTEM image of one of the multiply twinned decahedral gold structure). . . . . . . . . . . 57 xxii
4.2 (a) BF XTEM image of as-deposited samples 5 nm Au/SiO2/Si(100) and (b) corresponding HRTEM image. (c) shows the XTEM image of the 5 nm Au/SiO 2 /Si(100) taken at RT after annealed upto 975 o C and (d) corresponding HRTEM image. . . . . . . . . . . . . . . . . . . . . 58 4.3 (a)SEM image of as-deposited samples 11.7 nm Au/SiO 2 /Si(100)(b) SEM image taken at RT after annealed upto 975 o C and (c) corresponding XTEM image. . . . . . . . . . . . . . . . . . . . . . . . . . 59 4.4 SEM image of 50nm Au/SiO 2 /Si(100) heated upto 975 o C (a) elemental mapping which shows the presence of substrate silicon (b) and Au (c) and corresponding EDX spectrum (d). . . . . . . . . . . . . . . . . . 59 4.5 (a) SEM image of as deposited samples 50 nm Au/SiO 2 /Si(100), (b) SEM image taken at RT after the sample was annealed upto 975 o C (inset figure shows SEM image taken at 5 KeV electron energy), (c) corresponding XTEM image and (d) SAD pattern taken on one of the Au island. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 4.6 SEM image shows the (a) 11.7nm Au grown by MBE (without native oxide at the interface) method which is annealed upto 975 o C inside LV and (b)corresponding XTEM image (inset figure shows the SAD pattern) (c) thermally grown (with oxide) 11.7 nm Au annealed upto 975 o C inside HV and (d)corresponding XTEM image . . . . . . . . . 61 4.7 (a)SEM image of thermally grown 50 nm Au heated upto 975 o C inside HV (b) corresponding Bright field TEM image and (c) the HRTEM image shows the presence of gold silicide. . . . . . . . . . . . . . . . . 63 4.8 (a) STEM image from 50 nm Au/SiO x /Si(100) annealed at 975 o C. (b) is the region taken at higher magnification from a selected area in (a). Fig. c(i) is from the Oxygen EELS line scan from region (i) and d(ii) is from the region (ii) shown in (b). Width of the variation of oxide layer thickness can be seen in (c) and (d)[161]. . . . . . . . . . . . . . 64 4.9 SEM image of 50 nm Au/thermally grown 50 nm SiO x /Si(100) substrate annealed at 975 o C under low vacuum ((inset figure shows SEM image taken at 5 KeV electron energy.) . . . . . . . . . . . . . . . . . 65 4.10 (a) SEM based EBSD orientation mapping in 50 nm Au/SiO x /Si(100) annealed at 975 o C, (b) and (c) corresponding inverse pole figures (d) histogram plot of the misorientation angle Vs number fraction [161]. . 66 xxiii
Page 1: DYNAMIC AND STATIC TEM STUDIES ON T
Page 4 and 5: Declaration I, Ashutosh Rath, hereb
Page 6 and 7: a special word of appreciation for
Page 8 and 9: List of Publications 1. 1‡ Epitax
Page 10 and 11: Muller,M. Schowalter, R.Imlau, A. R
Page 12 and 13: Synopsis The thesis work involves a
Page 14 and 15: gold nanostructures on Si (100) sur
Page 16 and 17: Au-Ge bilobed structures were forme
Page 18 and 19: Contents Statement By Author Declar
Page 20 and 21: 8 Summary 107 A Table to summarize
Page 24 and 25: 4.11 (a) SEM image taken at 54 o ti
Page 26 and 27: 6.7 Schematic diagram showing the A
Page 28 and 29: Introduction 2 giant magneto-resist
Page 30 and 31: Introduction 4 metals, in the case
Page 32 and 33: Introduction 6 and has been develop
Page 34 and 35: Experimental techniques 8 2.2 Thin
Page 36 and 37: Experimental techniques 10 for mono
Page 38 and 39: Experimental techniques 12 Layer pl
Page 40 and 41: Experimental techniques 14 signific
Page 42 and 43: Experimental techniques 16 Instrume
Page 44 and 45: Experimental techniques 18 Figure 2
Page 46 and 47: Experimental techniques 20 spherica
Page 52 and 53: Experimental techniques 26 a dynami
Page 54 and 55: Experimental techniques 28 that are
Page 56 and 57: Experimental techniques 30 componen
Page 60 and 61: Experimental techniques 34 electron
Page 64 and 65: Chapter 3 Temperature-dependent ele
Page 66 and 67: Temperature-dependent electron micr
Page 72 and 73:
Temperature-dependent electron micr
Page 74 and 75:
Page 76 and 77:
Page 78 and 79:
Page 80 and 81:
Chapter 4 Growth of Oriented Au Nan
Page 82 and 83:
Growth of Oriented Au Nanostructure
Page 84 and 85:
Page 86 and 87:
Page 88 and 89:
Page 90 and 91:
Page 92 and 93:
Page 94 and 95:
Page 96 and 97:
Structural modification of gold sil
Page 98 and 99:
Page 100 and 101:
Page 102 and 103:
Page 104 and 105:
Page 106 and 107:
Page 108 and 109:
Page 110 and 111:
Nano scale phase separation in Au-G
Page 112 and 113:
Page 114 and 115:
Page 116 and 117:
Page 118 and 119:
Page 120 and 121:
Page 122 and 123:
Page 124 and 125:
Gold assisted molecular beam epitax
Page 126 and 127:
Page 128 and 129:
Page 130 and 131:
Page 132 and 133:
Page 134 and 135:
Summary 108 square /rectangular sha
Page 136 and 137:
Summary 110 the annealed sample whi
Page 138 and 139:
Bibliography [1] M. S. Gudiksen, L.
Page 140 and 141:
BIBLIOGRAPHY 114 [32] Y. He, X. Yu
Page 142 and 143:
BIBLIOGRAPHY 116 [67] M. Ohring Mat
Page 144 and 145:
BIBLIOGRAPHY 118 [97] W. K. Chu, J.
Page 146 and 147:
BIBLIOGRAPHY 120 [131] C. Suryanara
Page 148 and 149:
BIBLIOGRAPHY 122 [167] C. R. Henry,
Page 150:
BIBLIOGRAPHY 124 [201] E. Sutter an
show all

PHYS Ashutosh Rath - Homi Bhabha National Institute

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?