Mechanism and Equivalent Circuit Model of Multielement Metal-Oxide Thin-Film Photodetectors

In this paper, photodetector devices with a trilayer structure of p+-Si-substrate (p+-Si)/multielement metal-oxide thin film (MO)/indium tin oxide thin film (ITO) were built, and the associated possible mechanism was discussed. An equivalent circuit model for trilayer photodetectors based on the band structure and I–V characteristic was developed. The I–V characteristics and the equivalent circuit model of the photodetector based on the energy band structure were verified via HSPICE simulation and were investigated comprehensively. The accuracy of the simulation results was greater than 99%. This work paves the way for understanding the working mechanism as well as the potential application for optimizing device fabrication for multielement photodetectors.