Enhanced Electro-Static Discharge Endurance of GaN-Based Light-Emitting Diodes with Specially Designed Electron Blocking Layer

Abstract

GaN-based light-emitting diodes (LEDs) with specially designed electron blocking layers (EBLs) between the multiple quantum wells (MQWs) and the top p-GaN layer have been developed. The EBLs consist of Mg-doped p-AlGaN/GaN superlattice (SL) with the layer thickness of p-AlGaN varied from 1 to 10 nm and the layer thickness of p-GaN fixed at 1 nm in this study. It was found that under a 2000 V reverse bias voltage condition, the electro-static discharge (ESD) yield increased from 61.98 to 99.51% as the thickness of p-AlGaN in the EBLs was increased from 1 to 10 nm. Since the ESD yield was 97.80%, and maximum value for LEDs' light output power (LOP) and minimum value for the forward voltage (Vf) were achieved when the thickness of p-AlGaN in the EBLs was 9 nm with a 20 mA injection current, it was concluded that the p-AlGaN/GaN SL EBLs with the combination of 9-nm-thick p-AlGaN and 1-nm-thick p-GaN would be beneficial to the fabrication of the GaN-based LEDs with high brightness, high ESD endurance, and low Vf.