Advances in Visible-Shortwave Infrared Broadband InGaAs Photodetectors

With the shift of the photoelectric detection working band to infrared, the visual information in visible and near-infrared bands covered by traditional silicon-based image sensors can no longer meet the needs of space remote-sensing, industrial monitoring, and other fields. Shortwave infrared detectors are gradually entering the expanding application field of image vision by virtue of the unique information contained in their wavebands and the reflective imaging principle similar to that of visible cameras. Among these, the InGaAs shortwave infrared photodetector is the most mature and widely developed owing to its high quantum efficiency, mobility, and sensitivity. Visible extended-shortwave infrared broadband InGaAs photodetectors have become an important research direction to meet the demands of low-light-level and multispectral imaging. At present, there are two common development approaches: increasing the light absorption and adopting a new heterojunction. The former can be divided into surface thinning treatment and anti-reflection technology, whereas the latter mainly refers to InGaAs and two-dimensional materials or Ⅲ-Ⅴ materials other than InP to form a new heterojunction detector. In this study, the development of broadband InGaAs detectors in the ⅥS-SWIR spectrum both domestically and internationally is summarized, and the new structure and technology of InGaAs photodetectors are expounded and analyzed. Finally, future development trends in broadband InGaAs infrared detectors are summarized and discussed.