UVM Theses and Dissertations
Format:
Print
Author:
Nguyen, Thang
Dept./Program:
Electrical and Computer Engineering
Year:
2004
Degree:
Ph. D.
Abstract:
The lattice constant of GaSb is closely matched to that of InAs and AISb. Together these three materials form the 6.1 Family of semiconductors that has the potential to produce novel heteroepitaxial structures. These heteroepitaxial structures can then be used to produce both high speed and opto-electronic devices as a result of their other superior physical properties. This family also presents the potential for producing a wide range of III-V ternary and quaternary alloys with useful band gap and carrier transport properties. This thesis describes the heteroepitaxial growth of GaSb thin film materials on a number of substrate materials. The investigation also determines that the presence of an initial Sb buffer layer is a critical factor in the growth of high crystalline quality GaSb layers. Other factors that are found to be critical to the resulting GaSb film quality were substrate temperature and duration of thin film growth. A particularly interesting observation was that the GaSb film grew off-axis by 4.3 degrees from the surface normal on the Si (111) substrate. This phenomenon was further investigated with growth on tilted substrate wafers, and its evolution through a combination of Atomic Force Microscopy and Rutherford Backscattering Spectrometry.