Large‐Format Room‐Temperature Visible‐to‐Mid‐Infrared Broadband Imaging Enabled by a Single 2D Active Material

Abstract

Broadband imaging across visible, near‐infrared, and mid‐infrared (VIS‐NIR‐MIR) is a long‐standing goal for applications spanning machine vision, autonomous navigation, remote sensing, and biomedical monitoring. However, current approaches typically require multiple single‐band detectors or heterogeneous material stacks to cover different spectral windows, which add substantial optical and fabrication complexity. Here, we report a large‐pixel‐count, room‐temperature VIS‐NIR‐MIR broadband image sensor enabled by a detector‐array vertical photodiode architecture that uses large‐scale two‐dimensional (2D) black phosphorus (BP) films as a single active material. Operating at room temperature under zero bias, the BP film photodiodes exhibit an intrinsically broadband response spanning 532 nm to 6.2 µm, with specific detectivity ranging from 1.36 × 107 cm Hz1/2 W−1 at 6.2 µm to 1.0 × 108 cm Hz1/2 W−1 at 3.7 µm. We further achieve monolithic integration of the 2D BP film photodiodes with a 640 × 512 silicon readout integrated circuit (ROIC), enabling large‐pixel‐count VIS‐NIR‐MIR broadband imaging using a single active material for the first time, to the best of our knowledge. This work establishes a scalable, ROIC‐compatible, chip‐scale imaging platform and provides a pathway toward compact, low‐cost, large‐pixel‐count broadband cameras operating across the VIS‐NIR‐MIR spectral regions.