Ultraviolet photodetector based on p+-Si/n-ZnO bilayer structure

Ultraviolet (UV) photoresponse characteristics have been demonstrated in a p+-Si/n-ZnO bilayer structure photodetector. Unlike single-layer ZnO photodetectors, the device can be regarded as two series-connected p-n junctions. The photo-induced carriers can be effectively modulates by built-in electric field during light on/off switching cycles. In contrast to conventional lateral carrier transport, longitudinal carrier movement in this structure significantly shortens charge migration paths. Consequently, the bilayer structure device exhibits superior performance metrics, demonstrating enhanced responsivity and accelerated response speeds compared to single ZnO photodetector.