Impact of Fabrication Variabilities on Performance of Avalanche Photodetectors

Avalanche photodetectors (APDs) are a crucial technology for detection of weak optical signals. These devices operate on internal gain, meaning only the device currents, including the optical signal, are amplified [1] . This allows high performance APDs to maximize their signal-to-noise ratio as long as the excess noise due to the amplification process remains low. In this work, we investigate how slight geometric changes to a device design due to variabilities in the fabrication process can affect the performance of an APD. The performance metrics considered are gain, excess noise factor, and bandwidth.