| abstract |
An avalanche photodiode and a manufacturing method therefor, which relates to the field of communications and can solve the problem that a dark current of an existing avalanche photodiode is high. The avalanche photodiode comprises: a germanium GeOI substrate on an insulator, and intrinsic germanium (I-Ge) absorption layer (31), used for absorbing a light signal and generating a photon-generated carrier; a first p-type silicon germanium (SiGe) layer (23), a second p-type silicon germanium (SiGe) layer (24),a first silicon germanium (SiGe) layer (21), and a second silicon germanium (SiGe) layer (22), the content of Si in the silicon germanium (SiGe) layer being lower than 20%; a first silicon dioxide (SiO2) oxide layer (72) and a second silicon dioxide (SiO2) oxide layer (73); a first Taper-type silicon (Si) waveguide layer (11) and a second Taper-type silicon (Si) waveguide layer (12); a n-type heavily-doped Si multiplication layer (13); and an anode electrode (61) and a cathode electrode (62). |