Selective growth of GaN by liquid phase electroepitaxy using aluminum oxide mask

Abstract

Aluminum oxide was investigated as a mask material for the selective growth of GaN by liquid phase electroepitaxy in comparison with SiO 2 , SiN, and W. SiO 2 and W masks were dissolved in a solution and many polycrystals were generated on the SiN mask. Therefore, these masks are not suitable for selective growth. On the other hand, aluminum oxide was found durable in the solution, and growth selectivity was also achieved. Then, microchannel epitaxy was conducted using the aluminum mask by liquid phase electroepitaxy. Not only the selective growth but also the lateral growth of c-plane GaN with a width of about 8 µm was successfully achieved using the aluminum oxide mask.

Lateral growth of GaN by liquid phase electroepitaxy using mesa-shaped substrate

“…However, although the lateral growth of GaN was successfully achieved using MCE with an aluminum oxide mask, the reduction in the density of dislocations was not sufficient. 26,27) This was possibly because the side surface of the grown layer was inclined, particularly during the initial stage of growth, which caused the dislocations to bend and spread into the laterally grown area, as illustrated in Fig. 1.…”