MASKLESS LATERAL EPITAXIAL OVERGROWTH OF ALUMINUM NITRIDE AND HIGH ALUMINUM COMPOSITION ALUMINUM GALLIUM NITRIDE

摘要

A method of maskless lateral epitaxial overgrowth of aluminum nitride and high aluminum composition aluminum gallium nitride layers by crystal growth techniques, such as metalorganic chemical vapor deposition , Hydride Vapor Phase Epitaxy , other vapor phase transport techniques such as sublimation, and Molecular Beam Epitaxy . The process etches periodic patterns into a suitable material, such as aluminum nitride and high aluminum composition A1GaN base layers heteroepitaxially grown on a substrate or a substrate itself (step 18) A lateral epitaxial overgrowth is performed of the A1N or high aluminum composition aluminum gallium nitride layers on the suitable material. Lateral epitaxial overgrowth of the A1N or high aluminum composition aluminum gallium nitride layers may be enhanced using low V/III ratios and fast growth rates (step 20). The process reduces the threading dislocation density in high A1 containing nitrides by several orders of magnitude.