Dark current modeling of thick perovskite X-ray detectors
Shan Zhao, Xinyuan Du, Jincong Pang, Haodi Wu, Zihao Song, Zhiping Zheng, Ling Xu, Jiang Tang, Guangda Niu
Abstract
Abstract Metal halide perovskites (MHPs) have demonstrated excellent performances in detection of X-rays and gamma-rays. Most studies focus on improving the sensitivity of single-pixel MHP detectors. However, little work pays attention to the dark current, which is crucial for the back-end circuit integration. Herein, the requirement of dark current is quantitatively evaluated as low as 10 −9 A/cm 2 for X-ray imagers integrated on pixel circuits. Moreover, through the semiconductor device analysis and simulation, we reveal that the main current compositions of thick perovskite X-ray detectors are the thermionic-emission current ( J T ) and the generation-recombination current ( J g-r ). The typical observed failures of p–n junctions in thick detectors are caused by the high generation-recombination current due to the band mismatch and interface defects. This work provides a deep insight into the design of high sensitivity and low dark current perovskite X-ray detectors. Graphical Abstract