Design of high quantum efficiency SPAD single-photon detector based on metasurface

This work discusses several metasurface structure types, their manufacturing processes, and the design and simulation of nanopyramid arrays, square slot arrays, and funnel arrays to improve absorption. In particular, a silicon-based continuous thin gold film-covered deep grooved thin metal structure was constructed and examined. It surpasses the silicon materials’ absorption thresholds, considerably expanding the NIR’s absorption range to 2000 nanometers. More information is provided regarding the impact of trench depth on cavity pattern and near-infrared absorption. Its preparation process is detailed, and its compatibility with SPAD single-photon detectors is confirmed. This information is likely to encourage the use of SPAD in domains such as near-infrared optical communication and other low-light detecting technologies.