Gate-tunable optoelectronic properties of a nano-layered GaSe photodetector

Recently, two-dimensional materials were widely studied as candidates for a new generation of photodetectors. In this paper, we reported on the fabrication and the optoelectronic characterizations of a p-type gallium selenide (GaSe) back-gated field effect transistor based photodetector. The phototransistor showed excellent gate control capability with an ION/IOFF value exceeding 10(3). The photoresponsivity can be easily tunable to maximum value of 1.4 AW(-1) by changing the gate voltage; however, the photodetector showed the best performance at a gate voltage of - 18V, with photoresponsivity, external quantum efficiency, and detectivity of 0.9 AW(-1), 210% and 8.08 x 1011 cmHz(0.5)W-(1), respectively. (C) 2017 Optical Society of America