A study of reactive ion etching damage effects in GaN
This paper presents a study of dry-etch-induced damage effects on GaN films grown on SiC substrates. Photoluminescence (PL) of the control sample and samples exposed to Ar, SF6, SF6+N2 and N2 plasmas have been studied. In general, etching is found to decrease the donor-bound exciton (DX) intensity. X-ray photoelectron spectroscopy (XPS) has been employed to analyse the surface atomic concentration of all samples. Incorporation of nitrogen has been found on GaN surfaces exposed to N-containing plasmas. Langmuir probe has been used to quantify the amount of ion bombardment during plasma etching by measuring the ion flux. The effect of etching in an N2 plasma and annealing in an N2 ambient on the optical properties of the GaN surface has been compared and found to be significantly different.
reactive ion etching gan dry-etch