Photoelectric characteristics of Al-doped ZnO/p-Si diode prepared by radio frequency magnetron sputtering

Abstract

Al-doped ZnO (AZO) thin films were deposited on p-type silicon (p-Si) substrates by radio frequency magnetron sputtering technology. The crystal structure, morphology characterization and elemental analysis show that AZO film grows along the c-axis (002) orientation without other impurities. The current-voltage and current-time characteristics under different illumination conditions demonstrate that the Au/AZO/p-Si diode has typical rectification behavior, excellent stability and repeatability. The photocurrent is proportional to the intensity of ultraviolet irradiation, and the photocurrent reaches 110 μA at a bias voltage of 5 V under 11.75 mW/cm2 ultraviolet light irradiation. By calculating the conduction band and valence band offset values of AZO/p-Si heterojunction, the energy band diagrams at different bias states are constructed to explain the photoelectric response behavior. These results will be helpful for the design of high-performance photodiodes.