Self-heating dependent characteristic of GaN-based light-emitting diodes with and without AlGaInN electron blocking layer

Abstract

In this study, GaN-based light-emitting diodes (LEDs) with and without AlGaInN electron blocking layer (EBL) under self-heating effect are numerically studied. The energy band diagram, carrier transport and distribution characteristics, internal Joule heat and non-radiative recombination heat characteristics, and internal quantum efficiency are investigated. The effect of Auger recombi- nation coefficient on efficiency droop under self-heating effect is also studied. The simulation results show that efficiency droop is markedly improved when an AlGaInN EBL is placed between p-type GaN layer and active region. However, the chip temperature of LED is significantly increased simultaneously. The results also indicate that Auger recombination can be neglected because it is not the major contributor for the internal heat source. The effi- ciency droop is unrelated to the internal heat source. However, both electron leakage and Auger recombination play important roles in efficiency droop mechanism under self-heating effect.