Electrical and Optical Characteristics of MoOx/ZnO Based Thin Film Photodetector

This work reports the optical characteristics of MoO
₂
/ZnO thin films based ultra-violet (UV) photodetector. The substrate used for the fabrication of UV detector is p-Si over which a thin film of Al
₂
O
₃
(150 nm) is deposited. Photoactive layer of ZnO thin film (100 nm) is deposited epitaxially over the Al
₂
O
₃
using spin coating technique. At the top of solution processed ZnO thin film MoO
₂
(25 nm) is deposited. Aluminum is used as a top (50 nm) and bottom (80 nm) electrode deposited using thermal evaporation. The fabricated device forms a junction between MoO
₂
and ZnO which is characterized under the monochromatic UV light (650, μW at 365 nm). Th achieved responsivity of the device is 2.33 A/W. Further, the thin film of the ZnO is analyzed for optical characteristics and the obtained band gap is 3.31 eV.