Improved characteristics of reactive-ion-etching damage for n-GaN epitaxial layers after post-etch treatments

摘要

Reactive ion etched (RIE) surfaces of n-type GaN epitaxial films were investigated It is found that the recovery of crystal damage in optical properties can be achieved up to 60-65% of the photoluminescence (PL) peaks before RIE processing, for the samples thermally annealed at 750 /spl deg/ C for 3 minutes. By using transmission-line model, it is evident that KOH surface treatment prior to contact deposition is more effective in lowering contact resistance than that of the damaged surface only restored by RTA processing.