Modeling and study of MgZnO/CdZnO MQW LED with p–GaN/AlGaN cladding/EB layer

Abstract

We propose a multi–quantum–well (MQW) light–emitting–diode (LED) design including p–GaN/p–AlGaN/MgxZn1–xO/CdxZn1–xO/n– MgxZn1–xO /n–ZnO structure. The effect of different Mg and Cd molar fraction, thickness of quantum barrier, number of quantum well and carrier concentration of p–GaN layer on the performance of the proposed structure are studied through 2D simulation by ATLAS. The optimal xMg= 0.22 and xCd= 0.003 is determined through optimization process. Also, the optimal thickness of 5 nm for quantum barrier and the optimal number of 2 quantum wells is achieved for the proposed structure. To increase/decrease as much as possible the internal quantum efficiency/efficiency droop of the device, different affecting parameters are varied. The carrier concentration of p–GaN layer was revealed as the most affecting factor on the increase of quantum efficiency and reduction of the efficiency droop.