# US 10,374,107 B2 · Optical waveguide integrated light receiving element and method of manufacturing the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,374,107 B2 - Document ID: US10374107B2 - Status: Granted - Kind: B2 - Application number: 16/093,133 - Filed: 2017-04-14 - Published: 2019-05-23 - Granted: 2019-08-06 - Earliest claimed: 2016-04-19 - Assignees: Nippon Telegraph and Telephone Corporation - Applicants: Nippon Telegraph and Telephone Corporation - Inventors: Masahiro Nada; Yoshifumi Muramoto; Hideaki Matsuzaki - Web page: https://patentgrep.com/patent/US10374107B2 ## CPC - G02B 6/12004: {Combinations of two or more optical elements} - H10F 77/413: {directly associated or integrated with the devices, e.g. back reflectors (directly associated or integrated with photovoltaic cells H10F77/42)} - G02B 6/12: of the integrated circuit kind (electric integrated circuits H10B, H10D84/00 - H10D89/00, H10F19/00, H10F39/00, H10H29/00, H10K19/00, H10K39/00, H10K59/00, H10N19/00, H10N39/00, H10N59/00, H10N69/00, H10N79/00, H10N89/00) - G02B 6/13: Integrated optical circuits characterised by the manufacturing method - G02B 6/4295: {coupling with semiconductor devices activated by light through the light guide, e.g. thyristors, phototransistors} - H10F 30/225: the potential barrier working in avalanche mode, e.g. avalanche photodiodes - H10F 30/2255: {in which the active layers form heterostructures, e.g. SAM structures} - H10F 71/1272: {comprising at least three elements, e.g. GaAlAs or InGaAsP} - H10F 71/129: {Passivating} - H10F 77/1248: {having three or more elements, e.g. GaAlAs, InGaAs or InGaAsP} - H10F 77/306: {for devices having potential barriers} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION ## Abstract An optical waveguide integrated light receiving element includes an optical waveguide (105) arranged on a side of a second contact layer (102) opposite to a side where a light absorption layer (103) is arranged, having a waveguide direction parallel to a plane of the light absorption layer (103), and optically coupled with the second contact layer (102). The second contact layer (102) has, in a planar view, a size of an area smaller than that of the light absorption layer (103) and arranged inside the light absorption layer (103). ## Claims ### Claim 1 An optical waveguide integrated light receiving element comprising: a first contact layer made of a compound semiconductor of a first conductivity type; a second contact layer made of a compound semiconductor of a second conductivity type; a light absorption layer made of a compound semiconductor and formed between the first contact layer and the second contact layer; a multiplication layer made of a compound semiconductor and formed between the light absorption layer and one of the first contact layer and the second contact layer; and an optical waveguide arranged on a side of the second contact layer opposite to a side where the light absorption layer is arranged, having a waveguide direction parallel to a plane of the light absorption layer, and optically coupled with the second contact layer, wherein the second contact layer has, in a planar view, a size of an area smaller than that of the light absorption layer, and arranged inside the light absorption layer in the planar view. ### Claim 2 (depends on 1) The optical waveguide integrated light receiving element according to claim 1, further comprising an optical matching layer of the second conductivity type that is formed in contact with the side of the second contact layer where the light absorption layer is arranged, and an impurity concentration of the optical matching layer is equal to or less than an impurity concentration of the second contact layer. ### Claim 3 (depends on 1) The optical waveguide integrated light receiving element according to claim 1, further comprising a passivation layer configured to cover a side portion of a light receiving element including the first contact layer, the second contact layer, the light absorption layer, and the multiplication layer, and the passivation layer has a refractive index lower than that of a semiconductor that forms the light receiving element. ### Claim 4 A method of manufacturing an optical waveguide integrated light receiving element, comprising: a first step of producing, on a substrate, a light receiving element including: a first contact layer made of a compound semiconductor of a first conductivity type; a second contact layer made of a compound semiconductor of a second conductivity type; a light absorption layer made of a compound semiconductor and formed between the first contact layer and the second contact layer; and a multiplication layer made of a compound semiconductor and formed between the light absorption layer and one of the first contact layer and the second contact layer, wherein the second contact layer has, in a planar view, a size of an area smaller than that of the light absorption layer, and arranged inside the light absorption layer; a second step of producing an optical waveguide substrate including an optical waveguide; and a third step of wafer-bonding the substrate and the optical waveguide substrate and obtaining a state in which the optical waveguide is arranged on a side of the second contact layer opposite to a side where the light absorption layer is arranged, the optical waveguide has a waveguide direction parallel to a plane of the light absorption layer, and is optically coupled with the second contact layer. ### Claim 5 (depends on 2) The optical waveguide integrated light receiving element according to claim 2, further comprising a passivation layer configured to cover a side portion of a light receiving element including the first contact layer, the second contact layer, the light absorption layer, and the multiplication layer, and the passivation layer has a refractive index lower than that of a semiconductor that forms the light receiving element.