Ultralow dark-current self-powered VS2/SiO2/Si MIS photodiode for highly sensitive broadband detection
Jiawen Guo, Zhihui Zhao, Xue Li, Cha Xiu Guo, Zhiheng Mo, Cheng Jia, Longhui Zeng, Xinjian Li, Di Wu
Abstract
Widely used silicon (Si)-based optoelectronic components based on PN or Schottky junctions face issues such as high noise levels and poor weak-light detection capabilities. Herein, we present a high-performance 1T-VS2/SiO2/Si metal–insulator–semiconductor photodiode. By inserting an ultrathin insulating layer to increase the barrier height and suppress carrier tunneling, the photodiode achieves an ultralow dark current of 2 × 10−13 A and a sensitive self-powered photoresponse across the ultraviolet to short-wavelength near-infrared spectrum. Significantly, it exhibits a maximal ratio of photocurrent to dark current (Ilight/Idark) up to 107 and can detect weak light signals down to 80 nW/cm2. Our study offers a strategy to suppress dark current and enhance sensitivity in zero-energy optoelectronic devices, showing great potential for weak-light sensing and broadband photodetection applications beyond Si-detection limits.