Efficiency Enhancement of GaN Based Light-emitting Diodes with a Heterojunction Type Last Quantum Barrier

Abstract

A GaN/Al0.15Ga0.85N/GaN heterojunctionis designed to enhance the electron confinement and improve the hole injection efficiency of GaN-based MQW LEDs. The physical and optical properties of GaN-based MQW LEDs with and without the heterojunction structure are investigated. The simulation results show that the LEDs with the heterojunction structure quantum barrier exhibit much higher output power and lower threshold voltage as compared to those with the traditional structure due to the enhancement of the electron confinement and improvement of the hole injection from p-type region, which are induced by the strong reverse electrostatic fields in the heterojunction structure