Performance investigation of p-i-n ZnO-based thin film homojunction ultraviolet photodetectors

The p-i-n ZnO-based ultraviolet (UV) photodetectors was deposited using the vapor cooling condensation system. The rejection ratio between the ultraviolet and the visible was 2.82 × 103 measured at a reverse bias of −1 V. The low-frequency noise, which was dominated by the flicker noise, exhibited the noise equivalent power of 1.70 × 10−12 W and the high detectivity of 5.53 × 1011 cm Hz1/2W−1 with the illumination wavelength of 360 nm at the reverse bias voltage of −1 V. The high performances were attributed to the low defects and interface states present in the p-i-n ZnO-based ultraviolet photodetectors prepared using the vapor cooling condensation system.