Title : High-speed high-efficiency silicon-based photodetectors with photon-trapping holes
Abstract:
Monolithic infrared detectors with high speed and high efficiency have important applications in optical communication, signal measurement and other fields. Si is the best candidate material for monolithic integrated photodetectors, but the absorption coefficient of Si in near-infrared band is significantly reduced. Aiming at the contradiction between high absorption (high efficiency) and high speed (large bandwidth) of Si-based photodetectors in the near-infrared band, a Si film based photodetector integrated with periodic photon-trapping holes is proposed, which can ensure ultra-fast response speed and significantly enhance the absorption of near-infrared light. The spectral response range is also improved by combining Si with other semiconductor materials such as lead selenide (PbSe) film and quantum dot. The author introduces the research progress in photon-trapping mechanism, material synthesis, structure design, manufacturing process, and test verification of Si film based infrared detector. High speed (FWHM < 30 ps) and high efficiency (EQE > 60%) Si based infrared detectors are realized. It lays the theoretical and technical foundation for the development and application of monolithic integrated photodetectors with high performance.
