Novel Approaches to Realizing Chemical Lift-off of GaN Epilayer from Sapphire Substrate

摘要

Chemical lift-off (CLO) technique has been paid more attention since no damages will be induced to GaN epi-layer during the epilayer lift-off process. In this study two novel CLO approaches were used to separate GaN epilayer from sapphire substrate. One is using Ga_2O_3 sacrificial layer deposited by pulsed laser deposition. The other is using a stripe patterned SiO_2 grown by PECVD. Afterwards, the CLO of GaN epilayers grown on these two templates via metal organic chemical vapor deposition from sapphire substrate was successfully realized with a hydrofluoric acid as an etchant.