| The main theme of this dissertation is to explore the possible methods to.;achieve controllable and optimized modifications of the fundamental properties.;of chalcogenides.;The first kind is about the structural modifications through light exposure. The.;shape changes of the thin film are created when exposed to light pattern. We.;then investigate the mechanisms of photo-induced surface relief formation. We.;derive a generalized model to explain the spatial and temporal evolution of.;photoinduced surface structure in photosensitive amorphous thin films. The model.;describes these films as an incompressible viscous fluid driven by a.;photoinduced pressure originating from dipole rearrangement. This derivation.;requires only the polarizability, viscosity and surface tension of the.;system. Using values of these physical parameters, the validity of the model is.;checked by fitting to experimental data of arsenic sulfide and demonstrating good.;agreement.;Another way of modifications is achieved by the doping of silver nanoparticles.;We achieve the in-situ and uniform generation of Ag nanoparticles in.;chalcogenide solution using laser ablation. Ag-doped chalcogenide films are.;fabricated by spin-coating the resulting solution. The prepared solution and.;films are analyzed using transmission electron microscopy, dynamic light.;scattering and UV-vis spectroscopy to investigate particle shape and size.;distributions. Uniform doping has been achieved.;Besides, we are able to incorporate a variety of ions into chalcogenide glassy.;matrices using in-situ wet chemistry processing. Various chlorides are.;incorporated into chalcogenide matrices, leading to various property changes,;such as absorption and refractive indices.;In addition, we also explore modifications through photonic crystals. We use.;silicon photonic crystals with angstrom surface roughness to spatially confine.;the solution processed arsenic sulfide and achieve controllable modulations of.;chalcogenides emission. A planar emitter array of chalcogenides is fabricated.;based on this novel periodic hetero-structures of semiconductor. |
