High‐speed silicon avalanche photodiodes with built‐in field

摘要

High‐speed silicon avalanche photodiodes for the near‐infrared region are reported. Diodes are provided with a built‐in field by a graded impurity distribution which accelerates photocarriers in a light‐absorption region. The response for a mode‐locked Nd : YAG laser pulse is as narrow as 200 psec. Typical quantum efficiency is 0.55 at 0.80 μm and 0.49 at 0.83 μm. The gain‐bandwidth product is 460 GHz at a multiplication factor of 400. The built‐in field is effective in realizing high‐speed avalanche photodiodes with a low breakdown voltage.