# US 2019/0355776 A1 · Imaging device and imaging system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0355776 A1 - Document ID: US20190355776A1 - Status: Published application - Kind: A1 - Application number: 16/526,168 - Filed: 2019-07-30 - Published: 2019-11-21 - Earliest claimed: 2017-02-07 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Takeshi Uchida; Jun Iba - Web page: https://patentgrep.com/patent/US20190355776A1 ## CPC - H10F 39/18: Complementary metal-oxide-semiconductor [CMOS] image sensors; Photodiode array image sensors - H04N 25/76: Addressed sensors, e.g. MOS or CMOS sensors - H10F 39/151: {Geometry or disposition of pixel elements, address lines or gate electrodes} - H10W 90/00: Package configurations - H10F 55/00: Radiation-sensitive semiconductor devices covered by groups H10F10/00, H10F19/00 or H10F30/00 being structurally associated with electric light sources and electrically or optically coupled thereto - H10H 29/142: {Two-dimensional arrangements, e.g. asymmetric LED layout} - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS ## Abstract An imaging device includes a first substrate in which a plurality of first pixels each including a first light receiving unit and a light emitting unit that emits light with a light amount in accordance with a light amount detected by the first light receiving unit are provided, and a second substrate that is provided facing the first substrate and in which a plurality of second pixels each including a second light receiving unit that detects a light emitted from the light emitting unit of the first pixel and a readout circuit that outputs an image signal based on information detected by the plurality of second pixels are provided. ## Claims ### Claim 1 An imaging device comprising: a first substrate in which a plurality of first pixels each including a first light receiving unit and a light emitting unit that emits light with a light amount in accordance with a light amount detected by the first light receiving unit are provided; and a second substrate that is provided facing the first substrate and in which a plurality of second pixels each including a second light receiving unit that detects a light emitted from the light emitting unit of the first pixel and a readout circuit that outputs an image signal based on information detected by the plurality of second pixels are provided, wherein a plurality of compound semiconductor layers including a first compound semiconductor layer of a first conductivity type, a second compound semiconductor layer of a second conductivity type provided over the first compound semiconductor layer, and a third compound semiconductor layer of the first conductivity type provided over the second compound semiconductor layer is provided over the first substrate, and wherein a thickness of the second compound semiconductor layer is thicker than a thickness corresponding to a diffusion length of carriers of the first conductivity type in the second compound semiconductor layer. ### Claim 2 (canceled) ### Claim 3 (depends on 1) The imaging device according to claim 1, wherein the plurality of compound semiconductor layers includes a light receiving layer of the first light receiving unit provided between the first compound semiconductor layer and the second compound semiconductor layer and a light emitting layer of the light emitting unit provided between the second compound semiconductor layer and the third compound semiconductor layer, and wherein an energy band gap of a first compound semiconductor material forming the light receiving layer and an energy band gap of a second compound semiconductor material forming the light emitting layer are different from each other. ### Claim 4 (depends on 3) The imaging device according to claim 3, wherein the energy band gap of the second compound semiconductor material is larger than the energy band gap of the first compound semiconductor material. ### Claim 5 (depends on 1) The imaging device according to claim 1, wherein the plurality of compound semiconductor layers include an InP layer. ### Claim 6 (depends on 3) The imaging device according to claim 3, wherein an absorption wavelength band of a semiconductor material forming the second light receiving unit is on a longer wavelength side than an absorption wavelength band of the first compound semiconductor material. ### Claim 7 (depends on 6) The imaging device according to claim 6, wherein the semiconductor material is silicon. ### Claim 8 (depends on 1) The imaging device according to claim 1, wherein the first compound semiconductor layers of the plurality of first pixels and the third compound semiconductor layers of the plurality of first pixels are electrically connected, respectively. ### Claim 9 (depends on 1) The imaging device according to claim 1, wherein at least a part of the plurality of first pixels each include an individual electrode electrically connected to the second compound semiconductor layer. ### Claim 10 (depends on 1) The imaging device according to claim 1, wherein in the third compound semiconductor layer of each of the plurality of first pixels, an in-plane distribution is provided in impurities of the first conductivity type such that the light emitting unit locally, intensely emits light. ### Claim 11 (depends on 1) The imaging device according to claim 1, wherein each of the plurality of first pixels further includes an electrode electrically connected to the third compound semiconductor layer, and wherein the electrode functions as a light shield wall that prevents a light emitted from the light emitting unit of a first pixel from entering another second pixel that is different from a second pixel corresponding to the first pixel. ### Claim 12 (depends on 1) The imaging device according to claim 1 further comprising a first lens that is provided on the second substrate and converges light emitted from the light emitting unit on the second light receiving unit. ### Claim 13 (depends on 1) The imaging device according to claim 1 further comprising a second lens that is provided on the first substrate and converges light emitted from the light emitting unit on the second light receiving unit. ### Claim 14 (depends on 1) The imaging device according to claim 1, wherein each of the plurality of first pixels has a mesa structure in which at least the light emitting unit is independent of one another and includes a light shield film over a sidewall of the mesa structure. ### Claim 15 (depends on 1) The imaging device according to claim 1, wherein an air gap or a layer made of a material that is transparent to a light emitted from the light emitting unit is provided between the first substrate and the second substrate. ### Claim 16 (depends on 1) An imaging system comprising: the imaging device according to claim 1; and a signal processing unit that processes the image signal output from the imaging device. ### Claim 17 An imaging device comprising: a first substrate in which a plurality of first pixels each including a first light receiving unit and a light emitting unit that emits light with a light amount in accordance with a light amount detected by the first light receiving unit are provided; and a second substrate that is provided facing the first substrate and in which a plurality of second pixels each including a second light receiving unit that detects a light emitted from the light emitting unit of the first pixel and a readout circuit that outputs an image signal based on information detected by the plurality of second pixels are provided, wherein a plurality of compound semiconductor layers including a first compound semiconductor layer of a first conductivity type, a second compound semiconductor layer of a second conductivity type provided over the first compound semiconductor layer, and a third compound semiconductor layer of the first conductivity type provided over the second compound semiconductor layer is provided over the first substrate, wherein the second compound semiconductor layer includes an InP layer, and wherein a thickness of the second compound semiconductor layer is thicker than 5 μm. ### Claim 18 An imaging device comprising: a first substrate in which a plurality of first pixels each including a first light receiving unit and a light emitting unit that emits light with a light amount in accordance with a light amount detected by the first light receiving unit are provided; and a second substrate that is provided facing the first substrate and in which a plurality of second pixels each including a second light receiving unit that detects a light emitted from the light emitting unit of the first pixel and a readout circuit that outputs an image signal based on information detected by the plurality of second pixels are provided, wherein a plurality of compound semiconductor layers including a first compound semiconductor layer of a first conductivity type, a second compound semiconductor layer of a second conductivity type provided over the first compound semiconductor layer, and a third compound semiconductor layer of the first conductivity type provided over the second compound semiconductor layer is provided over the first substrate, and wherein the second compound semiconductor layer includes a blocking layer configured to suppress diffusion of minority carriers.