Photodiode and electronic device including the same

An optical integrated circuit comprising:

• an optical waveguide;
• and
• an optical sensing element configured to couple light traveling along the optical waveguide to generate an electrical signal corresponding to the light,
• wherein the optical sensing element comprises:
• a substrate;
• a first silicon semiconductor layer on the substrate in a first direction;
• a second silicon semiconductor layer on the substrate in the first direction, and spaced apart from the second silicon semiconductor layer in the first direction;
• and
• a germanium semiconductor layer between the first silicon semiconductor layer and the second silicon semiconductor layer, the germanium semiconductor layer comprising germanium,
• wherein the first silicon semiconductor layer comprises:
• a first region comprising an intrinsic silicon semiconductor;
• and
• a second region comprising a silicon semiconductor doped with a first conductivity type dopant, and
• wherein the germanium semiconductor layer comprises an intrinsic germanium semiconductor, and an entirety of the intrinsic germanium semiconductor of the germanium semiconductor layer does not include a dopant.

A method of manufacturing an optical sensing element, comprising:

• forming an intrinsic germanium semiconductor layer on a substrate;
• forming a silicon semiconductor layer that covers an entire upper surface of the intrinsic germanium semiconductor layer;
• forming a doped silicon semiconductor region in the silicon semiconductor layer by injecting a dopant into the silicon semiconductor layer, wherein the doped silicon semiconductor region has a thickness from an upper surface of the silicon semiconductor layer, and the thickness of the doped silicon semiconductor region is less than an entire thickness of the silicon semiconductor layer;
• and
• forming a conductive layer, wherein the conductive layer is in contact with the doped silicon semiconductor region.