Effect of multiquantum barriers in performance enhancement of GaN-based light-emitting diodes

Abstract

InGaN/GaN multiple quantum well light-emitting diodes (LEDs) with the AlGaN electron blocking layer and AlGaN/GaN multiquantum barriers (MQBs) have been investigated numerically. Using the AlGaN/GaN MQBs, the LEDs exhibit enhanced light output power and reduced turn-on voltage. Simulation results show that although the quantum mechanical reflection/transmission effect of the MQBs can aggravate the electron leakage, the effective barrier height for electrons is increased and that for holes is decreased due to polarization fields related to the band-bending, which is the main reason behind the improved performance of GaN-based LEDs employing the MQBs.