Recessed AlGaN/GaN UV Phototransistor

Abstract

We developed an AlGaN/GaN heterojunction phototransistor with a recessed detection area to enhance the photoresponsivity. The recessed-AlGaN/GaN phototransistor exhibited a maximum photoresponsivity of 1.6 x 10(7) A/W at 375 nm, which was similar to 30% higher than that obtained with a conventional AlGaN/GaN phototransistor. A comparable photoresponsivity was also achieved at 260 nm in UV-C range due to the dual absorption process in conjunction with the polarization induced built-in electric field characteristics of AlGaN/GaN heterojunction.