Engineered Silicon Avalanche Photodetectors: Mechanisms and Performance Optimization

Silicon avalanche photodiodes (APDs) exhibit excellent performance, including high speed, high responsivity, and high sensitivity in amplification of optical signals by virtue of avalanche multiplication effect, which holds considerable importance in weak light detection. Here, a systematic review on the research progress of Si‐APDs is presented. First, the typical device structures and working mechanisms of Si‐APDs are introduced. Subsequently, the optimizations of structural design and fabrication processes of Si‐APDs, as well as their impacts on the performance, are discussed. Finally, the present challenges and future development trends of Si‐APDs are prospected.