Characterization of m-GaN and a-GaN Crystallographic Planes after Being Chemically Etched in TMAH Solution

This paper proposes a new technique to engineer the Fin channel in vertical GaN FinFET toward straight and smooth sidewall. Consequently, wet etching TMAH solution is detailed; we found that m-GaN plane has lower surface roughness than crystallographic planes with other orientations, including a-GaN plane. The grooves slope (Cuboids) at base are also investigated. agitation does not assist Cuboid removal or rate enhancement. Finally, impact of UV light on m crystal rates been studied without light. Accordingly, it enhanced from 0.69 1.09 nm/min light; case etching, enhances 2.94 4.69 nm/min.