Investigation of the effect of nitride-based LEDs fabricated using hole injection layer at different growth temperatures

Abstract

In this study, the fabrication of blue InGaN/GaN light-emitting diodes (LEDs) using a hole injection layer (HIL) grown at different temperatures was demonstrated and the LEDs were investigated. The LEDs with HIL grown at 870 °C show a higher light output power and a lower efficiency droop ratio. This can be attributed to the improvement of the spontaneous and piezoelectric polarization-induced field effects [i.e., quantum-confined stark effect (QCSE)] of LEDs. However, the growth temperature of HIL at 840 °C was very low and resulted in excessive Mg atom doping, which would cause point defect generation and rapid hole concentration drop. On the other hand, the LEDs with HIL grown at 900 °C exhibit better electrostatic discharge (ESD) endurance and higher hot/cold factors owing to the lower defect density. Overall, the LEDs with HIL grown at 870 °C show better properties than the other LEDs.