Uniformity improvement of thickness and net donor concentration in halide vapor phase epitaxial β-Ga2O3 wafers prepared on miscut angle substrates

Abstract

High uniformity of the thickness and net donor concentrations (N d-N a) in 100 mm diameter β-Ga2O3 (001) epitaxial wafer prepared by halide vapor phase epitaxy was demonstrated. An epitaxial wafer grown on a substrate with a miscut angle near 0° generated a specific epitaxial region with a lower growth rate and a higher N d-N a than the rest of the region, which deteriorated the wafer uniformity. In contrast, epitaxial wafers prepared on substrates with a miscut angle of –0.1° suppressed the occurrence of the specific epitaxial region, and an average thickness after chemical mechanical polishing of 10.6 μm with 5% tolerance and an average N d-N a without intentionally doping of 1.1 × 1016 cm−3 within 7% tolerance were successfully obtained.