Improved Light Output Power in GaN-based Vertical Light-emitting Diodes with p-AlInGaN/GaN Superlattices

Abstract

In this paper, we report the effect of p-type AlGaInN/GaN superlattices (SLs) as electron-blocking layers (EBLs) on the optical properties of vertical light-emitting diodes (VLEDs). Using p-AlGaInN/GaN SLs in VLEDs, we have achieved significant improvements in the output power and the external quantum efficiency (EQE) as compared to VLEDs using p-AlGaInN EBL and pAlGaN EBL. The forward voltages at 350 mA were calculated to be 4.1, 4.3, and 4.4 V for VLEDs with p-AlInGaN/GaN SLs, p-AlInGaN, and p-AlGaN EBLs, respectively. When p-AlInGaN/GaN SLs were inserted as the EBLs, the light-output power and the EQE were also improved by 16.8% and 17.3% at 350 mA, respectively, as compared to those with p-AlGaN EBLs.