Self-Powered ZnO Nanowire UV Photodetector Integrated With GaInP/GaAs/Ge Solar Cell

摘要

This letter reports the fabrication of a ZnO nanowire (NW) ultraviolet (UV) metal–semiconductor photodetector (MS-PD) integrated with a GaInP/GaAs/Ge triple-junction (TJ) solar cell. The ZnO NW MS-PD can detect UV light ${<}{370}~{rm nm}$. The TJ solar cell transforms solar light to electrical power and provides a bias of 2.5 V to enhance the response of the detector. At this bias, the UV-to-visible (370 to 500 nm) rejection ratio of the ZnO NW MS-PD is ${sim}{218}$ and the measured responsivity is $3.39times 10^{{-4}}~{rm A}/{rm W}$. In addition, the dynamic response of the ZnO NW MS-PD under the UV light illumination of 370 nm is stable and reproducible with an ON/OFF current ratio of ${sim}{rm 1000}$.