Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008. / Doolittle, W. Alan, Committee Chair ; Ferguson, Ian T., Committee Member ; Cressler, John D., Committee Member ; Dorsey, John F., Committee Member ; Carter, W. Brent, Committee Member.

abstract: ABSTRACT Group III-nitride semiconductor materials have been commercially used in fabrication of light-emitting diodes (LEDs) and laser diodes (LDs) covering the spectral range from UV to visible and infrared, and exhibit unique properties suitable for modern optoelectronic applications. Great advances have recently happened in the research and development in high-power and high-efficiency blue-green-white LEDs, blue LDs and other optoelectronic applications. However, there are still many unsolved challenges with these materials. In this dissertation, several issues concerning structural, electronic and optical properties of III-nitrides have been investigated using a combination of transmission electron microscopy (TEM), electron holography (EH) and cathodoluminescence (CL) techniques. First, a trend of indium chemical inhomogeneity has been found as the indium composition increases for the InGaN epitaxial layers grown by hydride vapor phase epitaxy. Second, different mechanisms contributing to the strain relaxation have been studied for non-polar InGaN epitaxial layers grown on zinc oxide (ZnO) substrate. Third, various structural morphologies of non-polar InGaN epitaxial layers grown on free-standing GaN substrate have been investigated. Fourth, the effect of the growth temperature on the performance of GaN lattice-matched InAlN electron blocking layers has been studied. Finally, the electronic and optical properties of GaN nanowires containing a AlN/GaN superlattice structure have been investigated showing relatively small internal electric field and superlattice- and defect-related emissions along the nanowires. / Dissertation/Thesis / Ph.D. Physics 2011

Thesis (Ph. D.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains xvii, 161 p. : ill. Includes abstract. Includes bibliographical references (p. 154-161).

Thesis (M.S.)--Ohio University, March, 2000. / Title from PDF t.p.

Thesis (Ph. D.)--University of Canterbury, 2006. / Typescript (photocopy). "May 2006." Includes bibliographical references (leaves [173]-186). Also available via the World Wide Web.

Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains viii, 139 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 107-108).

Master of Science / Department of Mechanical and Nuclear Engineering / Jeffrey Geuther / William L. Dunn / The properties of hexagonal boron nitride (h-BN) as a semiconductor neutron detection medium were investigated. Single h-BN crystal domains were synthesized by the Chemical Engineering department at Kansas State University (KSU) using crystallization from molten metal solutions. At Texas Tech University (TTU), a detector was fabricated using epitaxial h-BN growth on a sapphire substrate where metallic micro-strip contacts 5 [mu]m apart and 5 nm thick where deposited onto the un-doped h-BN. In this research both the crystal domains synthesized at KSU and the detector fabricated at TTU were tested for neutron response. Neutron irradiation damage/effects were studied in pyrolytic h-BN by placing samples in the central thimble of the TRIGA MARK II reactor at KSU and irradiating at increasing neutron fluences. The domains synthesized at KSU as well as the detector fabricated at TTU showed no response to neutron activity on a MCA pulse height spectrum. Conductivity analysis showed abrupt increases in the conductivity of the pyrolytic h-BN at around a fluence of 10[superscript]1[superscript]4 neutrons per cm[superscript]2. Bandgap analysis by photoluminescence on the irradiated pyrolytic h-BN samples showed shifts in energy due to towards plane stacking disorders upon neutron irradiation. Future efforts may include the introduction of dopants in h-BN growth techniques for charge carrier transport improvement, and mitigation of plane stacking disorders.

Thesis (M. Phil.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 75-77).

Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains xi, 100 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 68-73).

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 168-180).