Physical Sciences and Mathematics Commons^™

Mechanical, Electronic And Optical Properties Of Multi-Ternary Semiconductor Alloys, Dongguo Chen

Dissertations

The ability to obtain tunable properties with composition makes multi-ternary alloys extremely useful for a variety of applications in semiconductor devices and is of significant interest in experimental and theoretical research. This dissertation investigates the mechanical, electronic and optical properties of multi-ternary, i.e., binary, ternary and quaternary, semiconductor alloys using analytical methods and first-principles calculations.

For the calculations of mechanical properties, existing models on the average shear modulus of III-V & II-VI binary semiconductors are revised. New expressions are developed for the average Young’s modulus as well as the shear modulus and Young’s modulus on (111) plane for these compounds. …

Understanding The Origins Of Metastability In Thin Film Growth; Tantalum And The Early Group Vb-Vib Metals, Neme Okechukwu Nnolim

Dissertations

Tantalum (Ta) is a metal that is highly prized for its applications in a variety of industries, including the microelectronics industry, where it is largely used in thin film modifications in order to achieve various electronic, magnetic and structural capabilities in solid-state devices. Ta frequently forms metastable phases, including the well-known ß-phase, during the preparation of thin Ta films by standard film deposition methods such as sputtering and electro-deposition. In order to gain insight into Ta metastable phase formation, the Bain transformation mechanism is studied for Ta and the neighboring body centered cubic (bcc) transition metals in Groups 5 and …