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Pui-kong Lim. / Thesis (M.Phil.)--Chinese University of Hong Kong. / Bibliography: leaves 73-75.

by Lui Ka Man Raymond. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 190-202). / by Lui Ka Man Raymond. / Acknowledgements / Abstract / Table of contents --- p.i / Chapter Chapter 1 --- Introduction / Chapter 1.1) --- General overview --- p.1 / Chapter 1.2) --- The present study --- p.4 / Chapter Chapter 2 --- Theory / Chapter 2.1) --- Introduction --- p.8 / Chapter 2.2) --- Energy transfer from an incoherent radiation source --- p.9 / Chapter 2.3) --- Interaction between photons and solid --- p.11 / Chapter 2.4) --- Probability of a direct transition of amorphous germanium to liquid germanium --- p.12 / Chapter 2.5) --- Crystallization in the supercooled melts and interface stability of the crystallizing front --- p.20 / Chapter A) --- Homogeneous nucleation --- p.21 / Chapter B) --- Heterogeneous nucleation --- p.24 / Chapter C) --- Interfacial stability of the crystallizing front --- p.25 / Chapter Chapter 3 --- Sample preparation / Chapter 3.1) --- Introduction --- p.36 / Chapter 3.2) --- The sample preparation system --- p.36 / Chapter A) --- General description --- p.36 / Chapter B) --- The electron beam source and other components --- p.37 / Chapter C) --- The thermal pulse furnace (TPF) --- p.38 / Chapter 3.3) --- The substrates --- p.41 / Chapter 3.4) --- Sample preparations --- p.42 / Chapter Chapter 4 --- Dendritic crystallization of amorphous germanium on amorphous substrate / Chapter 4.1) --- Introduction --- p.47 / Chapter 4.2) --- Sample preparation and experimental methods --- p.48 / Chapter A) --- Sample preparation --- p.48 / Chapter B) --- Characterization methods --- p.50 / Chapter 4.3) --- Experimental results --- p.54 / Chapter 4.4) --- Discussions --- p.58 / Chapter A) --- Existence of a supercooled semiconductive liquid phase --- p.58 / Chapter B) --- Suppression of nucleation in the supercooled liquid --- p.61 / Chapter C) --- The effect of substrate width on the confinement of <110> crystal axes --- p.63 / Chapter D) --- The effect of annealing ambient --- p.63 / Chapter 4.5) --- Conclusions --- p.65 / Chapter Chapter 5 --- Transport properties of dendritic Ge films / Chapter 5.1) --- Introduction --- p.93 / Chapter 5.2) --- Theory --- p.93 / Chapter A) --- Expression of electrical drift mobility by the relaxation time approximation --- p.94 / Chapter B) --- Electrical drift mobility resulting from ionized impurity scattering --- p.98 / Chapter 5.3) --- Experimental methods --- p.102 / Chapter A) --- Sample annealing --- p.102 / Chapter B) --- Temperature-dependent electrical conductivity measurements (303 K - 523 K) --- p.102 / Chapter C) --- Temperature-dependent Hall mobility measurements (20 K - 300 K) --- p.103 / Chapter 5.4) --- Experimental results --- p.105 / Chapter A) --- Conductivity in the high temperature range K - 303 K --- p.105 / Chapter B) --- Sheet conductance in the temperature range 300K - 20 K --- p.105 / Chapter C) --- Hall mobility in the temperature range 300K to 20 K --- p.107 / Chapter 5.5) --- Discussions --- p.108 / Chapter A) --- Temperature dependence of electical conductivity --- p.108 / Chapter B) --- Temperature-dependent Hall mobility measurements --- p.111 / Chapter 5.6) --- Conclusions --- p.115 / Chapter Chapter 6 --- Crystallization of amorphous germanium film on (001) GaAs wafers / Chapter 6.1) --- Introduction --- p.131 / Chapter A) --- General review --- p.131 / Chapter B) --- The present study --- p.132 / Chapter 6.2) --- Sample preparation and experimental methods --- p.134 / Chapter A) --- Sample preparation --- p.134 / Chapter B) --- Characterization methods --- p.135 / Chapter 6.3) --- Experimental results --- p.143 / Chapter A) --- Epitaxial regrowth of a-Ge films on semi-insulating (001) GaAs --- p.144 / Chapter B) --- Influence of the substrate and the initial thickness of a-Ge film on the process of crystallization --- p.146 / Chapter C) --- Results from electron spectroscopy and EDX dot-map --- p.148 / Chapter D) --- The electrical property of the Ge/GaAs heterojunction --- p.150 / Chapter 6.4) --- Discussions --- p.150 / Chapter A) --- Substrate dependence --- p.150 / Chapter B) --- Sample thickness dependence --- p.153 / Chapter C) --- Regrowth mechanism --- p.154 / Chapter 6.5) --- Conclusions --- p.156 / Chapter Chapter 7 --- Conclusions and suggestions for further studies / Chapter 7.1) --- Conclusions --- p.183 / Chapter A) --- On amorphous substrate [Corning 7059 glass] --- p.183 / Chapter B) --- On crystalline substrate [GaAs (001) wafer] --- p.185 / Chapter 7.2) --- Suggestions for further studies --- p.186 / Chapter A) --- Synthesis of Ge/GaAs heterojunction with abrupt interface --- p.186 / Chapter B) --- Applying the thermal pulse annealing method to other systems --- p.186 / Chapter C) --- Studying the size and shape-dependence of Raman spectrum by using sample with highly uniform grain size and well-defined geometry --- p.187 / Appendix A --- p.188 / References --- p.190

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A fundamental study of the correlations between ion energy, substrate temperature, and plasma density with hydrogen content, percent sp2 bonding, optical gap, and refractive index of hydrogenated amorphous carbon (a-C) films is presented. A strong dependency between the ion energy used during deposition and the film’s microstructure is shown. Moreover, it is revealed that the optical properties of the a-C films are controlled by the concentration and size of sp2 clusters in the film. Through N2 mixing in the source gas, room-temperature nitrogen doped polymeric-like a-C films were demonstrated for the first time. X-ray Photoelectron Spectroscopy revealed an increase in the Fermi level of these films with increased nitrogen content. A proof-of-concept a-C based transparent heat mirror (THM) was demonstrated. It was shown that a-C acts as an oxygen-free protective barrier and anti-reflective coating for Ag films in the THM, increasing the transmission in the visible region by 10-20%.

A fundamental study of the correlations between ion energy, substrate temperature, and plasma density with hydrogen content, percent sp2 bonding, optical gap, and refractive index of hydrogenated amorphous carbon (a-C) films is presented. A strong dependency between the ion energy used during deposition and the film’s microstructure is shown. Moreover, it is revealed that the optical properties of the a-C films are controlled by the concentration and size of sp2 clusters in the film. Through N2 mixing in the source gas, room-temperature nitrogen doped polymeric-like a-C films were demonstrated for the first time. X-ray Photoelectron Spectroscopy revealed an increase in the Fermi level of these films with increased nitrogen content. A proof-of-concept a-C based transparent heat mirror (THM) was demonstrated. It was shown that a-C acts as an oxygen-free protective barrier and anti-reflective coating for Ag films in the THM, increasing the transmission in the visible region by 10-20%.

Over the past decades, bulk metallic glasses (BMGs) have attracted extensive interests because of their unique physical and chemical properties such as good corrosion resistance, larger elastic elongation limit and high strength and hardness. They are also seen as the potential material for micro-electro-mechanical systems (MEMS). However, despite many extraordinary properties in BMGs, BMGs might be difficult to be made into MEMS, different from thin film metallic glasses (TFMGs). Compared with BMGs, few studies have been carried out on TFMGs and their application for MEMS. In this study, efforts have been made to study the properties of multilayered TFMGs. The multilayer thin film selected in this thesis is amorphous/nanocrystalline nanolaminate systems. The micro-pillars of multilayered TFMGs with diameter of 1 £gm are fabricated by using focus ion beam (FIB) and tested in microcompression at room temperature. On nano-indentation test, the phenomenon of strain burst decreases by way of multilayer system. It means that the multilayer system can retard the shear band propagation initiated from the amorphous layers. Under the microcompression test, the deformation of both ZrCu (100 nm)/Cu (50 nm) and ZrCu (100 nm)/Cu (10 nm) multilayer micro-pillars are still dominated by the emission of shear bands in a manner of strain burst to release the energy, but the ZrCu (100 nm)/Cu (100 nm) multilayer thin films reveal continuous deformation and smooth stress-strain curve with no strain burst. First, the sufficient thick of copper layer can absorb more energy from shear deformation of amorphous layer. Second, the copper layer exhibits plastic flow along the transverse direction under the iso-stress deformation. The transverse plastic flow acts as a shear force at interface causing non-stress concentration at amorphous layer. It means that the amorphous layer can be deformed to large plastic strain without stress concentration, causing a homogeneous deformation. According to these two deformation mechanisms, it is possible that the ZrCu (100 nm)/Cu (100 nm) multilayer thin film is better system for improving the ductility of amorphous alloy with a good strength.