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. Crystal structure, morphology characterization and elemental analysis demonstrate that AZO film grows along the c-axis (002) orientation without other impurities. The current-voltage and current-time characteristics under different illumination conditions reveal the Au/AZO/p-Si diode has the typical rectification behavior, excellent stability and repeatability. We found that 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/cm 2 ultraviolet light irradiation. By calculating the conduction band and valence band offset values of AZO/p-Si heterojunction, the energy band diagrams at different states are constructed to explain the photoelectric response behavior. These results will be helpful for the design of high-performance photodiodes.

Keywords: Al-doped ZnO, radio frequency magnetron sputtering, ultraviolet irradiation, photoelectric characteristics