Polarity selective etching: A self-assisted route for fabricating high density of c-axis oriented tapered GaN nanopillars

Abstract

High density of c-axis oriented tapered GaN nanopillars are fabricated simply by exposing GaN epitaxial layers in argon-chlorine plasma without any prior lithographic processing. The nature and the formation process of the pillars are investigated by different optical and structural characterization techniques. Our study reveals that the pillars are columnar inversion domains with distinctly different optical properties as compared to the bulk. These are formed as a result of a polarity selective etching process. (C) 2011 American Institute of Physics. [doi:10.1063/1.3622142]