Metal-Organic Chemical Vapor Epitaxy of GaN on Si(111) for Optoelectronic Applications

摘要

Low temperature growth of gallium nitride on silicon via vapor phase epitaxy was investigated. The use of different nitrogen and gallium sources was explored. The gallium nitride deposition process was optimized by varying surface preparation, seed and buffer layer growth, and annealing conditions. Films were extensively characterized via X-ray diffraction, Rutherford backscatter, atomic force microscopy, X-ray photoemission spectroscopy, and Auger electron spectroscopy. Optimized growth rates of 60-120 A/min were achieved at 0.8 torr pressure, with 1:1 gallium to nitride ratio to within 0.1%. Films were hexagonal and polycrystalline with 3 nitride bi-layer buffers, with annealing, allowed stoichiometric gallium nitride growth of up to 6000 A, but the temperatures used were not high enough to deposit epitaxial gallium nitride.