Improved Reverse Leakage Current in GaInN-Based LEDs With a Sputtered AlN Buffer Layer

In this study, the improvement of reverse leakage current characteristics with a sputtered (SP)-AlN buffer layer in GaInN-based green light-emitting diodes (LEDs) has been presented for the first time. To understand the origin of the improvement, a detailed review and careful analysis of reverse leakage current characteristics were performed. The review and analysis identified that the improvement was primarily caused by the suppression of variable-range-hopping process obtained by replacing conventional low-temperature GaN buffer. Verification that threading dislocations and V-defects can enhance the variable-range-hopping process has been received. We believe that this study will contribute to the realization of green LEDs with advantages of high reliability, a long lifetime, and electrical robustness.