Highly selective GaN/AlGaN/GaN UV photodiodes

摘要

Al_(0.33)Ga_(0.67)N has a highly desirable bandgap for UV photodetection purposes, but fabricating photodiodes from this material is presently hindered by difficulties in growing high-quality doped layers. A recent solution to the doping problem has involved the fabrication of p-i-n diodes in which an undopded AlGaN layer is sandwiched between layers of doped GaN. An analysis of this structure is presented, with emphasis on how the unwanted photocurrent generated in the low-bandgap window layer can be suppressed.