GaN Epilayer Grown on Ga2O3 Sacrificial Layer for Chemical Lift-Off Application

Abstract

GaN-on-sapphire structure with a Ga2O3 sacrificial layer was employed for the chemical lift-off process application. The ((2) over bar 01) beta-oriented Ga2O3 thin film was first deposited on the c-plane sapphire substrate using pulsed laser deposition, followed by the GaN growth via metalorganic vapor phase epitaxy under N-2 and H-2 environment in sequence. From the transmission-electron-microscopy observation, the orientation relationship between GaN and beta-Ga2O3 was identified as GaN[11 (2) over bar0]parallel to Ga2O3[010]. A GaN epilayer with an electroplated copper substrate was demonstrated using a chemical lift-off process where the Ga2O3 sacrificial layer can be laterally etched out with a hydrofluoric solution. (C) 2011 The Electrochemical Society. [DOI: 10.1149/2.002111esl] All rights reserved.