Te_xSe_{1- x} Shortwave Infrared Photodiode Arrays with Monolithic Integration

Te_xSe_1-x shortwave infrared (SWIR) photodetectors show promise for monolithic integration with readout integrated circuits (ROIC), making it a potential alternative to conventional expensive SWIR photodetectors. However, challenges such as a high dark current density and insufficient detection performance hinder their application in large-scale monolithic integration. Herein, we develop a ZnO/Te_xSe_1-x heterojunction photodiode and synergistically address the interfacial elemental diffusion and dangling bonds via inserting a well-selected 0.3 nm amorphous TeO₂ interfacial layer. The optimized device achieves a reduced dark current density of -3.5 × 10^-5 A cm^-2 at -10 mV, a broad response from 300 to 1700 nm, a room-temperature detectivity exceeding 2.03 × 10¹¹ Jones, and a 3 dB bandwidth of 173 kHz. Furthermore, for the first time, we monolithically integrate the Te_xSe_1-x photodiodes on ROIC (64 × 64 pixels) with the largest-scale array among all Te_xSe_1-x-based detectors. Finally, we demonstrate its applications in transmission imaging and substance identification.