Self-Powered p-GaN/i-ZnGa<sub>2</sub>O<sub>4</sub>/n-ITO Heterojunction Broadband Ultraviolet Photodetector With High Working Temperature
Yongxue Zhu, Kewei Liu, Xiaoqian Huang, Peixuan Zhang, Qiu Ai, Zhen Cheng, Jialin Yang, Xing Chen, Binghui Li, Lei Liu, Dezhen Shen
Abstract
A self-driven p-GaN/i-ZnGa2O4/n-ITO heterojunction broadband ultraviolet (BUV) photodetector was firstly demonstrated in this work with a high working temperature. In the 25–300 °C temperature range, the device exhibits excellent and stable BUV photodetection performance. Even at 300 °C, a large peak responsivity of ~132 mA/W, a broad UV response band ranging from 250 to 400 nm, a high UV-to-visible rejection ratio of nearly 104, and a high −3 dB cutoff frequency of 20 kHz can be still observed at 0 V, which is obviously superior to the other reported high-temperature BUV heterojunction photodetectors. The remarkable performance of our device at high temperature can be attributed to the excellent insulation and high crystalline quality of i-ZnGa2O4 layer, as well as the good electrical properties of p-GaN and n-ITO. Moreover, their wide and complementary band gaps make the device have a very broad UV detection band.