AlGaN multi-quantum barriers for electron blocking in group III-nitride devices

Abstract

In this paper we investigate the enhancement of electron blocking in AlGaN multi-quantum barriers (MQBs). Simulations of effective barrier height of Al0.2Ga0.8N/GaN-MQBs were performed in order to find optimal layer design. By using a strict optimization procedure the optimized MQB exhibits an increase of the effective barrier height of over 120 meV compared to a bulk electron blocking layer (EBL). This value was achieved for nearly all combinations of material parameters found in literature and for up to ±10 % layer thickness fluctuations. Based on the optimized design a sample series for experimental determination of effective barrier heights in AlGaN-MQBs is proposed.