Fabrication Of Transparent P-Nio/N-Zno Heterojunction Devices For Ultraviolet Photodetectors

摘要

An optically transparent p-n heterojunction device consisting of p-NiO and n-ZnO thin films was fabricated by r.f. sputtering method. The structural and optical properties of the p-NiO-ZnO heterojunction were characterized by X-ray diffraction (XRD), UV-visible spectroscopy, Hall effect measurement, andJ-V photocurrent measurements. The XRD shows that ZnO films are highly crystalline in nature with preferred orientation along the (0 0 0 2) direction. The p-NiO-ZnO heterojunction device has an average transmittance of over 80% in the visible region. The current-voltage curve of the heterojunction demonstrates obvious rectifying diode behavior in a dark environment. The lowest leakage current is 6.64 x 10~8A/cm2 for the p-NiO-ZnO heterojunction device.