Dry-etch damage and its recovery in InGaN/GaN multi-quantum-well light-emitting diodes

Abstract

Etch-induced damage in GaN/InGaN multi-quantum well light-emitting diodes (LEDs) caused by a Cl2-base plasma and its recovery by means of a N2-plasma and annealing process of n-GaN is described. The photoluminescence intensity of etched n-type GaN was decreased by several orders of magnitude due to etch-induced damage, giving rise to an increase in the leakage current in LED current–voltage curves. However, treatment of the LEDs with a N2 plasma along with a rapid thermal annealing process led to an enhancement in the I–V characteristics of the LEDs due to the suppression of the leakage current. The electroluminescence intensity of LEDs which was etched at dc bias of −200 V was also improved by a factor of two relative to the as-etched LEDs, as a result of this treatment.