Self-powered solar-blind ultraviolet photodetector based on Au/ZnMgO/ZnO:Al with comb-shaped Schottky electrode

Abstract

Abstract We have demonstrated a self-powered solar-blind ultraviolet (UV) photodetector based on the Au/ZnMgO/ZnO:Al vertical structure. The comb-shaped Au was selected as the Schottky electrode due to its high transmittance (more than 60%) in the wavelength region from 200\u202fnm to 300\u202fnm. At 0\u202fV bias, the detector showed a responsivity of 55\u202fmA/W under 265\u202fnm light illumination with the intensity of 80\u202fnW/cm2, which is larger than that of any other previously reported ZnO-based self-powered UV photodetectors. And a fast response speed can be also clearly observed with 10%–90% rise and 90%-10% decay times of 20\u202fμs and 300\u202fμs, respectively. The excellent self-powered solar-blind UV detection of our Au/ZnMgO/ZnO:Al device should be associated with the high external quantum efficiency, especially for the weak signal detection. Our findings offered new chances in high-performance self-powered photodetectors fabrication.