# US 2019/0244992 A1 · Imaging element and electronic device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0244992 A1 - Document ID: US20190244992A1 - Status: Published application - Kind: A1 - Application number: 16/341,974 - Filed: 2017-10-13 - Published: 2019-08-08 - Earliest claimed: 2016-10-27 - Assignees: Sony Semiconductor Solutions Corporation - Applicants: Sony Semiconductor Solutions Corporation - Inventors: Sozo Yokogawa; Mikinori Ito; Itaru Oshiyama - Web page: https://patentgrep.com/patent/US20190244992A1 ## CPC - H10F 39/8037: {the integrated elements comprising a transistor} - H04N 25/76: Addressed sensors, e.g. MOS or CMOS sensors - H10F 39/12: Image sensors - H10F 39/199: {Back-illuminated image sensors} - H10F 39/802: {Geometry or disposition of elements in pixels, e.g. address-lines or gate electrodes} - H10F 39/8023: {Disposition of the elements in pixels, e.g. smaller elements in the centre of the imager compared to larger elements at the periphery} - H10F 39/805: {Coatings} - H10F 39/8053: {Colour filters} - H10F 39/8067: {Reflectors} - H10F 39/807: {Pixel isolation structures} - H10F 39/813: {Electronic components shared by multiple pixels, e.g. one amplifier shared by two pixels} - H10F 39/8063: {Microlenses} - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract The present technology relates to an imaging element and an electronic device capable of improving sensitivity to infrared light in a back side irradiation imaging element. An imaging element is provided with a semiconductor substrate on which a photoelectric converting unit is formed, a wiring layer arranged on a side opposite to a light receiving surface of the semiconductor substrate, and provided with a wire and a reflective film, and an insulating film stacked between the semiconductor substrate and the wiring layer, in which the reflective film is arranged between the insulating film and the wire and overlaps with at least a part of the photoelectric converting unit of each pixel in a first direction in which the semiconductor substrate and the wiring layer are stacked, and a first interlayer film between the insulating film and the reflective film is thicker than the insulating film. The present technology is applicable to a back side irradiation CMOS image sensor, for example. ## Claims ### Claim 1 An imaging element comprising: a semiconductor substrate on which a photoelectric converting unit is formed; a wiring layer arranged on a side opposite to a light receiving surface of the semiconductor substrate, and provided with a wire and a reflective film; and an insulating film stacked between the semiconductor substrate and the wiring layer, wherein the reflective film is arranged between the insulating film and the wire and overlaps with at least a part of the photoelectric converting unit of each pixel in a first direction in which the semiconductor substrate and the wiring layer are stacked, and a first interlayer film between the insulating film and the reflective film is thicker than the insulating film. ### Claim 2 (depends on 1) The imaging element according to claim 1, wherein a thickness of the first interlayer film is in a range of 80 nm to 200 nm, and a thickness of the reflective film is in a range of 40 nm to 80 nm. ### Claim 3 (depends on 1) The imaging element according to claim 1, wherein, when a center wavelength of light reflected by the reflective film is set to λ, a refractive index of the first interlayer film is set to nA, a refractive index of the reflective film is set to nB, and i and j are integers of 0 or larger, a thickness of the first interlayer film is set in a vicinity of (2i+1)λ/4nA, and a thickness of the reflective film is set in a vicinity of (2j+1)λ/4nB. ### Claim 4 (depends on 1) The imaging element according to claim 1, wherein the first interlayer film includes a silicon oxide film or a silicon nitride film as a main component, and the reflective film includes polysilicon, amorphous silicon, or single crystal silicon as a main component. ### Claim 5 (depends on 1) The imaging element according to claim 1, wherein two or more reflective films are stacked through a second interlayer film. ### Claim 6 (depends on 5) The imaging element according to claim 5, wherein a thickness of the first and second interlayer films is in a range of 100 nm to 200 nm, and a thickness of the reflective film is in a range of 80 nm to 100 nm. ### Claim 7 (depends on 5) The imaging element according to claim 5, wherein, when a center wavelength of light reflected by the reflective film is set to λ, a refractive index of the first interlayer film and the second interlayer film is set to nA, a refractive index of the reflective film is set to nB, and i and j are integers of 1 or larger, a thickness of the first and second interlayer films is set in a vicinity of (λ×i)/4nA, and a thickness of the reflective film is set in a vicinity of (λ×j)/4nB. ### Claim 8 (depends on 5) The imaging element according to claim 5, wherein the first and second interlayer films include silicon oxide, silicon nitride, TiO2, or HfO2 as a main component, and the reflective film includes polysilicon, amorphous silicon, single crystal silicon, TaO, TfO, silicon nitride, Ge, SiC, TiN, Ti, TiO2, or NgF2 as a main component. ### Claim 9 (depends on 1) The imaging element according to claim 1, wherein the reflective film is arranged in a position not overlapping with a gate electrode of a transistor formed on a surface on a side opposite to the light receiving surface of the semiconductor substrate in the first direction. ### Claim 10 (depends on 1) The imaging element according to claim 1, wherein at least one of a shape, a size, or a position of the reflective film is different for each pixel. ### Claim 11 (depends on 10) The imaging element according to claim 10, wherein at least one of the shape, the size, or the position of the reflective film is adjusted corresponding to pupil correction. ### Claim 12 (depends on 1) The imaging element according to claim 1, wherein the reflective film is shared by a plurality of pixels. ### Claim 13 (depends on 1) The imaging element according to claim 1, wherein irregularities are formed on a surface of the reflective film. ### Claim 14 (depends on 1) The imaging element according to claim 1, wherein a trench-shaped pixel separating unit is formed between pixels on the semiconductor substrate, and a core is formed at a center of the pixel separating unit. ### Claim 15 (depends on 14) The imaging element according to claim 14, wherein the core includes polysilicon, amorphous silicon, or single crystal silicon as a main component, and the core is covered with a dielectric material including silicon oxide or silicon nitride as a main component. ### Claim 16 (depends on 15) The imaging element according to claim 15, wherein a thickness of the core in a second direction in which the pixels are adjacent is in a range of 50 nm to 200 nm, and a thickness of the dielectric material around the core in the second direction is in a range of 50 nm to 200 nm. ### Claim 17 (depends on 1) The imaging element according to claim 1, wherein an antireflective film is stacked on the light receiving surface of the semiconductor substrate, and when a center wavelength of light for which a reflection rate of the antireflective film is lowered is set to λ and a refractive index of the antireflective film is set to n, a thickness of the antireflective film is set in a vicinity of λ/4n. ### Claim 18 (depends on 1) The imaging element according to claim 1, wherein a diffraction structure is formed on the light receiving surface of the semiconductor substrate. ### Claim 19 (depends on 1) The imaging element according to claim 1, wherein a center wavelength of light reflected by the reflective film is 700 nm or longer. ### Claim 20 An electronic device, comprising: an imaging element; and a signal processing unit which processes a signal output from the imaging element, the imaging element including: a semiconductor substrate on which a photoelectric converting unit is formed; a wiring layer arranged on a side opposite to a light receiving surface of the semiconductor substrate, and provided with a wire and a reflective film; and an insulating film stacked between the semiconductor substrate and the wiring layer, wherein the reflective film is arranged between the insulating film and the wire and overlaps with at least a part of the photoelectric converting unit of each pixel in a first direction in which the semiconductor substrate and the wiring layer are stacked, and a first interlayer film between the insulating film and the reflective film is thicker than the insulating film.