High-responsivity AlGaN-GaN multi-quantum well UV photodetector

In this paper, we propose a set of AlGaN-GaN multi-quantum well (MQW) photodetectors based on p-i-n heterostructures with 14 AlGaN-GaN MQW structures in i-region, where GaN quantum well has 6nm thickness and AlxGa1-xN barrier thickness is 3nm. In this structure, the peak responsivity of 0.19A/W at 246nm is reported. In addition, we investigate effects of various parameters on responsivity, and we show that responsivity of MQW-based photodetectors strongly depends on proper device design, that is, number of quantum wells, well thickness, barrier thickness, and mole fraction. We also show that increasing number of quantum wells, thickness of wells, and mole fraction as well as decreasing thickness of barriers, increase the responsivity. Using obtained results, we proposed optimal structure. Copyright (c) 2013 John Wiley & Sons, Ltd.