Effect of WSe2 and PEDOT:PSS as Hole Transport Layers in SnS2/CuO-Based Photodetectors

This report analyses the effect of tungsten diselenide (WSe2) and PEDOT:PSS, as a hole transport layer (HTL) in copper oxide (CuO) and tin disulphide (SnS2) heterojunction based photodetector. The device having PEDOT:PSS hole transport layer offers a broad spectrum detection covering ultra-violet (300–400 nm), visible (400–800 nm), and near-infrared region (up to 1250 nm). On application of WSe2 as HTL, performance parameters of the photodetector are improved significantly. For the Al/SnS2/CuO/WSe2/ITO on PET device at 0.118 µW incident power (at 600 nm) and –1 V reverse bias, responsivity, external quantum efficiency, detectivity, and sensitivity are 81.34 A/W, 16812.11%, 1.47 × 1012 J, and 12.72, respectively. For Al/SnS2/CuO/PEDOT:PSS/ITO/PET device these values are 11.373 A/W, 1128.27%, 2.52 × 1011 J, and 2.69 at 1250 nm wavelength. The performance parameters obtained for device with WSe2 HTL prove its effectiveness as HTL.