High performance WSe2 and CuO heterojunction based photodetector for wearable devices

This letter reports a Al/Al2O3/CuO/WSe2/PEDOT:PSS/ITO structure photodetector for detection of green and red light. The p-type WSe2 layer forms a heterojunction with n-type CuO layer. The p-type PEDOT.PSS layer works as hole transport layer (HTL) and CuO layer work as (electron Transport layer) ETL whereas Al2O3 oxide layer work as hole blocking layer (HBL). The proposed photodetector, at-1.3V gives the high responsivity of 8.14A/W, detectivity as 4.27 × 1010 Jones and external quantum efficiency (EQE) as 1554% at 650 nm. The corresponding values at 550 nm are 6.87A/W, 3.61 × 1010 Jones and 1550% at 0.118 μW optical power. The proposed detector may efficiently be used for wearable devices.