Te _x Se _{1– x} Photodiode Shortwave Infrared Detection and Imaging

Abstract

Short‐wave infrared detectors are increasingly important in the fields of autonomous driving, food safety, disease diagnosis, and scientific research. However, mature short‐wave infrared cameras such as InGaAs have the disadvantage of complex heterogeneous integration with complementary metal–oxide–semiconductor (CMOS) readout circuits, leading to high cost and low imaging resolution. Herein, a low‐cost, high‐performance, and high‐stability Te _x Se _{1– x} short‐wave infrared photodiode detector is reported. The Te _x Se _{1– x} thin film is fabricated through CMOS‐compatible low‐temperature evaporation and post‐annealing process, showcasing the potential of direct integration on the readout circuit. The device demonstrates a broad‐spectrum response of 300–1600 nm, a room‐temperature specific detectivity of 1.0 × 10 ¹⁰ Jones, a −3 dB bandwidth up to 116 kHz, and a linear dynamic range of over 55 dB, achieving the fastest response among Te‐based photodiode devices and a dark current density 7 orders of magnitude smaller than Te‐based photoconductive and field‐effect transistor devices. With a simple Si ₃N ₄ packaging, the detector shows high electric stability and thermal stability, meeting the requirements for vehicular applications. Based on the optimized Te _x Se _{1– x} photodiode detector, the applications in material identification and masking imaging is demonstrated. This work paves a new way for CMOS‐compatible infrared imaging chips.