Faceting mechanisms of GaN nanopillar under KOH wet etching, in Materials Science in Semiconductor Processing.

This article presents strategies for achieving homogeneous array of high aspect ratio GaN pillars with the desired m- (or even a-) oriented nonpolar facets through a top-down approach that combines Cl2 plasma etching followed by room temperature KOH wet treatment. Our study highlights the key role played by both the shape and the roughness of the hard mask in determining the resulting crystalline facet formation and their associated roughness.

Keywords: GaN, Plasma etching, Chemical etching, Faceting, step-flow process.

L. Jaloustre, S. Sales De Mello, S. Labau, C. Petit-Etienne, E. Pargon,

Materials Science in Semiconductor Processing,Volume 173,2024,108095,

https://doi.org/10.1016/j.mssp.2023.108095.