Selective area growth of β-Ga 2 O 3 by HCl-based halide vapor phase epitaxy

We demonstrated selective area growth of β -Ga 2 O 3 by HCl-based halide vapor phase epitaxy on SiO 2 -masked (001) and (010) β -Ga 2 O 3 substrates. Perfect growth selectivity was achieved under the presence of HCl etching gas in addition to the growth precursors. In both substrate cases, (100) facet dominated the grown shapes owing to their smallest surface energy density. High-aspect-ratio structures having (100) sidewall facets were observed for the stripe windows along [010] and [001] directions on the (001) and (010) substrates, respectively. These structures may be applicable to trenches and fins used for β -Ga 2 O 3 -based power devices.