Binary response Se/ZnO p-n heterojunction UV photodetector with high on/off ratio and fast speed
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- 作者：Kai Hu ; Feng Teng ; Lingxia Zheng ; Pingping Yu ; Zhiming Zhang ; Hongyu Chen and Xiaosheng Fang
- 刊名：Laser & Photonics Reviews
- 出版年：2017
- 出版时间：January 2017
- 年：2017
- 卷：11
- 期：1
- 全文大小：901K
- ISSN：1863-8899
文摘
A high-performance UV photodetector (PD) based on a p-Se/n-ZnO hybrid structure with large area (more than 1×1 cm) is presented in this study. The device is theoretically equivalent to a parallel-connection circuit for its special structure and shows multifunction at different voltage bias, which means the output signal can be tailored by an applied voltage. The Se/ZnO PD shows binary response (positive and negative current output under on/off periodical light illumination) under small reverse bias (–0.05 V and –0.1 V) which efficiently reduces the negative effect of noise signal in weak-signal detection applications. At zero bias, with the aid of a p-n heterojunction, a high on/off ratio of nearly 104 is achieved by this device at zero set bias under 370 nm (∼0.85 mW cm−2) illumination and this on/off ratio can be achieved in 0.5 s. The device also shows a fast speed with rise time of 0.69 ms and decay time of 13.5 ms measured by a pulse laser, much faster than that of a pure ZnO film. The Se/ZnO PD in this research provides a new pathway to fabricate multifunctional high-speed, high signal-to-noise ratio, high detectivity and high selectivity UV photodetectors.