Pyramidal island for enhance response in ZnO/Cu2O heterojunction self-powered photodetector.

Self-powered photodetectors (PDs) with high performance are essential for applications in mobile portable electronics, communications, and sensing. However, the limited light absorption of the traditional planar heterojunction interface seriously restricts the commercial application of photodetectors. In this study, a new type PD with pyramidal island-like ZnO/Cu 2 O heterojunction interface was designed and prepared by electrochemical deposition and radio frequency (RF) magnetron sputtering technology using the inherent octahedral structure of Cu 2 O, and its unique pyramid island interface was conducive to improving the light utilization efficiency and photoelectric performance of the detector. Under zero bias conditions, the responsivities of 0.32 and 0.09 A W−1 were obtained under 380 nm and 550 nm illumination, respectively. And the PD exhibit fast rise and decay times of 0.163 and 0.179 s. The maximum external quantum efficiency reaches 107.18 %. The results demonstrate that our highly efficient and fast response self-powered PD is expected to be a candidate for next generation ultraviolet (UV) -visible photosensing applications. • The light-trapping structure in the solar cell is introduced into the photodetector. • The high response is due to light capture at the pyramidal island-like interface. • The photodetector is 4.2 times more responsive than planar structures. [ABSTRACT FROM AUTHOR]