| 摘要 |
PROBLEM TO BE SOLVED: To provide a mesa type avalanche photodiode having the small fluctuation amount of breakdown voltage characteristics, in addition to gigabit response characteristics and high reliability.SOLUTION: A multiplication layer 13 for amplifying a current signal, an electric field relaxing layer 14 for relaxing an electric field inside the multiplication layer 13, an etching stop layer 16 for preventing the electric field relaxing layer 14 from being etched in etching an upper layer, and a light absorption layer 17 for converting an optical signal into the current signal are laminated sequentially from a substrate 11 side. The light absorption layer 17 is formed in a mesa form on the etching stop layer 16. At least a side wall surface of the light absorption layer 17 is covered with a semiconductor protection film 111 formed of a semiconductor. The etching stop layer 16 is formed of a first conductive type semiconductor or a non-doped semiconductor. The electric field relaxing layer 14 is formed of the second conductive type semiconductor which is the opposite conductive type of the first conductive type semiconductor. |
