Ultrasensitive near-infrared photodetectors based on MoTe2 transistors with tunable photoresponse time

The efficient near-infrared light detection of MoTe2 transistors has been demonstrated. The fabricated MoTe2 phototransistors show good photoresponse performances under an illumination of a 915 nm laser. The photoresponsivity and detectivity can reach to 1479 A W-1, 8.2 x 10(11) Jones, respectively. Moreover, the photoresponse time can be effectively tuned by modulating the gate-source voltage. This mechanism could be explained by the depletion region width in channel is related to the gate-source voltage, and the Schottky barrier height between the MoTe2 channel and Pt source/drain metal is extracted to further confirm it. (C) 2019 The Japan Society of Applied Physics