# US 2019/0244993 A1 · Solid-state image pickup device and method of manufacture, 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 2019/0244993 A1 - Document ID: US20190244993A1 - Status: Published application - Kind: A1 - Application number: 16/319,382 - Filed: 2017-07-25 - Published: 2019-08-08 - Earliest claimed: 2016-08-08 - Assignees: Sony Semiconductor Solutions Corporation - Applicants: Sony Semiconductor Solutions Corporation - Inventors: TETSUJI YAMAGUCHI; ATSUSHI TODA - Web page: https://patentgrep.com/patent/US20190244993A1 ## CPC - H10F 39/8053: {Colour filters} - G02B 5/28: Interference filters - G02B 5/281: {designed for the infrared light} - G02B 5/286: {having four or fewer layers, e.g. for achieving a colour effect} - H04N 25/70: SSIS architectures; Circuits associated therewith - H10F 39/024: {of coatings or optical elements} - H10F 39/12: Image sensors - H10F 39/184: {Infrared image sensors} - 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 39/809: {of hybrid image sensors} - H04N 23/10: for generating image signals from different wavelengths - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract The present disclosure relates to a solid-state image pickup device and a method of manufacture, and an electronic device capable of suppressing occurrence of a transmission wavelength shift with a simpler design. The solid-state image pickup device includes a multilayer film filter having a laminated structure in which a transmission wavelength adjustment layer is sandwiched between a first multilayer film layer and a second multilayer film layer. Furthermore, the transmission wavelength adjustment layer is formed such that at least two types of dielectrics having different refractive indexes mixedly exist, and an effective refractive index is determined according to a ratio of the mixture. Then, the ratio of the mixture of the two types of dielectrics is adjusted such that the effective refractive index of the transmission wavelength adjustment layer gradually increases from a chip central portion in which an incident angle of light emitted onto the multilayer film filter is small toward a chip end portion in which the incident angle of light is large. The present technology can be applied to, for example, a back surface irradiation CMOS image sensor. ## Claims ### Claim 1 A solid-state image pickup device including at least a first layer having a first refractive index, a second layer having a second refractive index, and a third layer having a third refractive index, which are laminated, the solid-state image pickup device comprising: a multilayer film filter having a laminated structure in which the third layer is sandwiched between the first layer and the second layer, wherein the third layer is formed such that at least two types of dielectrics having different refractive indexes mixedly exist and an effective refractive index is determined according to a ratio of the mixture, and the ratio of the mixture of the two types of dielectrics is adjusted across a surface of the third layer such that the effective refractive index of the third layer gradually increases from a portion in which an incident angle of light emitted onto the multilayer film filter is small toward a portion in which the incident angle of light is large. ### Claim 2 (depends on 1) The solid-state image pickup device according to claim 1, wherein in a first dielectric serving as a base material having a predetermined refractive index, a second dielectric having a refractive index different from the refractive index of the first dielectric is embedded in the third layer so that the third layer includes a structure, which is formed by the second dielectric, having a size smaller than a transmission wavelength of light transmitted through the multilayer film filter. ### Claim 3 (depends on 2) The solid-state image pickup device according to claim 2, wherein a ratio of the second dielectric to the first dielectric is adjusted by changing a dimension of the structure according to the incident angle of light. ### Claim 4 (depends on 3) The solid-state image pickup device according to claim 3, wherein in a case where the refractive index of the first dielectric is smaller than the refractive index of the second dielectric, the ratio of the second dielectric to the first dielectric is adjusted by enlarging the dimension of the structure in a region in which the incident angle of light becomes large. ### Claim 5 (depends on 2) The solid-state image pickup device according to claim 2, wherein a ratio of the second dielectric to the first dielectric is adjusted by changing an arrangement density of the structure according to the incident angle of light. ### Claim 6 (depends on 5) The solid-state image pickup device according to claim 5, wherein in a case where the refractive index of the first dielectric is smaller than the refractive index of the second dielectric, the ratio of the second dielectric to the first dielectric is adjusted by increasing the arrangement density of the structure in a region in which the incident angle of light becomes large. ### Claim 7 (depends on 1) The solid-state image pickup device according to claim 1, wherein in the multilayer film filter, the effective refractive index of the third layer is set for each of a plurality of regions such that light in a different wavelength band is transmitted in each region, and in each of the regions, the ratio of the mixture of the two types of dielectrics is adjusted according to the incident angle of light. ### Claim 8 (depends on 1) The solid-state image pickup device according to claim 1, wherein the solid-state image pickup device has a structure in which the multilayer film filter, a photoelectric conversion layer in which a photoelectric conversion portion is formed for each pixel, and a readout circuit that reads a pixel signal from the photoelectric conversion layer are laminated in that order from a light incident surface side. ### Claim 9 (depends on 1) The solid-state image pickup device according to claim 1, wherein the third refractive index is smaller than the first refractive index and the second refractive index. ### Claim 10 (depends on 1) The solid-state image pickup device according to claim 1, wherein the first layer and the second layer are multilayer film layers in which a film including a material having a different refractive index is laminated. ### Claim 11 (depends on 1) The solid-state image pickup device according to claim 1, wherein the first refractive index and the second refractive index are substantially same. ### Claim 12 A method of manufacturing a solid-state image pickup device including at least a first layer having a first refractive index, a second layer having a second refractive index, and a third layer having a third refractive index, which are laminated, the solid-state image pickup device including: a multilayer film filter having a laminated structure in which the third layer is sandwiched between the first layer and the second layer, wherein the third layer is formed such that at least two types of dielectrics having different refractive indexes mixedly exist and an effective refractive index is determined according to a ratio of the mixture, the ratio of the mixture of the two types of dielectrics is adjusted across a surface of the third layer such that the effective refractive index of the third layer gradually increases from a portion in which an incident angle of light emitted onto the multilayer film filter is small toward a portion in which the incident angle of light is large, and the method comprises steps of: embedding, in a first dielectric serving as a base material having a predetermined refractive index, a second dielectric having a refractive index different from the refractive index of the first dielectric; and forming, using the second dielectric, a structure having a size smaller than a transmission wavelength of light transmitted through the multilayer film filter. ### Claim 13 An electronic device, comprising: a solid-state image pickup device including at least a first layer having a first refractive index, a second layer having a second refractive index, and a third layer having a third refractive index, which are laminated, the solid-state image pickup device including: a multilayer film filter having a laminated structure in which the third layer is sandwiched between the first layer and the second layer, wherein the third layer is formed such that at least two types of dielectrics having different refractive indexes mixedly exist and an effective refractive index is determined according to a ratio of the mixture, and the ratio of the mixture of the two types of dielectrics is adjusted across a surface of the third layer such that the effective refractive index of the third layer gradually increases from a portion in which an incident angle of light emitted onto the multilayer film filter is small toward a portion in which the incident angle of light is large.