# US 2013/0153976 A1 · Solid-state imaging apparatus, method of manufacturing solid-state imaging apparatus 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 2013/0153976 A1 - Document ID: US20130153976A1 - Status: Published application - Kind: A1 - Application number: 13/688,835 - Filed: 2012-11-29 - Published: 2013-06-20 - Earliest claimed: 2011-12-20 - Assignees: Sony Corporation - Inventors: Akiko Honjo - Web page: https://patentgrep.com/patent/US20130153976A1 ## CPC - H10F 77/00: Constructional details of devices covered by this subclass (constructional details of integrated devices, or assemblies of multiple devices, comprising at least one element in which radiation controls the flow of current H10F39/00) - H10F 39/014: {of CMOS image sensors} - H10F 39/807: {Pixel isolation structures} - H10F 71/133: {Providing edge isolation} - H10F 39/18: Complementary metal-oxide-semiconductor [CMOS] image sensors; Photodiode array image sensors - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION ## Abstract Provided is a solid-state imaging apparatus including: a plurality of photoelectric conversion units; an element isolation unit that performs element isolation between the plurality of photoelectric conversion units; and a diffusion prevention unit that prevents diffusion of a dark current component generated on an interfacial surface of the element isolation unit to a region surrounding the dark current component generation region. ## Claims ### Claim 1 A solid-state imaging apparatus comprising: a plurality of photoelectric conversion units; an element isolation unit that performs element isolation between the plurality of photoelectric conversion units; and a diffusion prevention unit that prevents diffusion of a dark current component generated on an interfacial surface of the element isolation unit to a region surrounding the dark current component generation region. ### Claim 2 (depends on 1) The solid-state imaging apparatus according to claim 1, wherein the diffusion prevention unit is formed along at least a bottom surface of the element isolation unit. ### Claim 3 (depends on 2) The solid-state imaging apparatus according to claim 2, further comprising a first conductive type first region that is formed deeper than the bottom surface of the element isolation unit, covers a side wall of the element isolation unit on a photoelectric conversion unit side, and has impurity concentration higher than a first conductive type well region of the surrounding of the photoelectric conversion units. ### Claim 4 (depends on 3) The solid-state imaging apparatus according to claim 3, wherein the diffusion prevention unit includes a first conductive type second region that is formed along the bottom surface of the element isolation unit, and the impurity concentration of the second region is lower than the impurity concentration of the well region. ### Claim 5 (depends on 4) The solid-state imaging apparatus according to claim 4, wherein the second region has a width in a depth direction of 5 nm to 50 nm. ### Claim 6 (depends on 4) The solid-state imaging apparatus according to claim 4, wherein the depth of the bottom surface of the second region is formed deeper than the bottom surface of the first region. ### Claim 7 (depends on 1) The solid-state imaging apparatus according to claim 1, wherein an element region to which a fixed potential is applied is provided on the side of the element isolation unit opposite to the photoelectric conversion units. ### Claim 8 (depends on 7) The solid-state imaging apparatus according to claim 7, wherein, by applying the fixed potential, the dark current component of which the diffusion is prevented by the diffusion prevention unit, is attracted by an electric field generated in the element region and flows into the element region. ### Claim 9 (depends on 7) The solid-state imaging apparatus according to claim 7, wherein the diffusion prevention unit is formed along the side wall on the side of the element isolation unit opposite to the photoelectric conversion units, so that the end portion of the element region side comes into contact with the element region. ### Claim 10 (depends on 7) The solid-state imaging apparatus according to claim 7, wherein the element region is a source/drain region of a pixel transistor, and a power supply potential is applied to the source/drain region. ### Claim 11 (depends on 10) The solid-state imaging apparatus according to claim 10, wherein the element isolation unit isolates the photoelectric conversion units from the pixel transistor. ### Claim 12 (depends on 10) The solid-state imaging apparatus according to claim 10, wherein the pixel transistor is a reset transistor that resets a floating diffusion region to which electric charge is transferred from the photoelectric conversion units. ### Claim 13 (depends on 10) The solid-state imaging apparatus according to claim 10, wherein the pixel transistor is an amplification transistor that amplifies a voltage according to electric charge of a floating diffusion region to which the electric charge is transferred from the photoelectric conversion units. ### Claim 14 (depends on 3) The solid-state imaging apparatus according to claim 3, wherein the diffusion prevention unit includes a first conductive type third region that is formed along the bottom surface of the element isolation unit by separating by only a predetermined interval from the bottom surface in a depth direction, and the impurity concentration of the third region is higher than the impurity concentration of the well region. ### Claim 15 (depends on 14) The solid-state imaging apparatus according to claim 14, wherein the first conductive type third region is formed so that the bottom surface is shallower than the bottom surface of the first region. ### Claim 16 (depends on 14) The solid-state imaging apparatus according to claim 14, wherein the first conductive type third region is provided by separating from the bottom surface of the element isolation unit by 5 nm to 10 nm in the depth direction. ### Claim 17 A method of manufacturing a solid-state imaging apparatus which includes a plurality of photoelectric conversion units, an element isolation unit that performs element isolation between the plurality of photoelectric conversion units, a diffusion prevention unit that prevents diffusion of a dark current component generated on an interfacial surface of the element isolation unit to a region surrounding the dark current component generation region, a first conductive type first region that is formed deeper than the bottom surface of the element isolation unit, covers the side wall of the element isolation unit on the photoelectric conversion unit side, and has impurity concentration higher than a first conductive type well region of the surrounding of the photoelectric conversion units, and a first conductive type second region that is formed along the bottom surface of the element isolation unit with impurity concentration lower than the impurity concentration of the well region, the method comprising: implanting a first conductive type impurity that covers the side wall region of the element isolation unit into the region between the photoelectric conversion units and the element isolation unit, before formation of the element isolation unit or after the formation of the element isolation unit, and implanting a second conductive type impurity into an opening region of a mask which forms the element isolation unit, with a dose amount having an extent to not reverse the conductive type of the well region, and with an energy to set an injection range Rp to have the same depth with the element isolation unit. ### Claim 18 A method of manufacturing a solid-state imaging apparatus which includes a plurality of photoelectric conversion units, an element isolation unit that performs element isolation between the plurality of photoelectric conversion units, a diffusion prevention unit that prevents diffusion of a dark current component generated on an interfacial surface of the element isolation unit to a region surrounding the dark current component generation region, a first conductive type first region that is formed deeper than the bottom surface of the element isolation unit, covers the side wall of the element isolation unit on the photoelectric conversion unit side, and has impurity concentration higher than a first conductive type well region of the surrounding of the photoelectric conversion units, and a first conductive type second region that is formed along the bottom surface of the element isolation unit with impurity concentration lower than the impurity concentration of the well region, the method comprising: implanting a second conductive type impurity into a formation region of the element isolation unit so as to be distributed in the vicinity of the depth of the element isolation unit before formation of the element isolation unit, and implanting a first conductive type impurity that covers the side wall region of the element isolation unit into the region between the photoelectric conversion units and the element isolation unit. ### Claim 19 A method of manufacturing a solid-state imaging apparatus which includes a plurality of photoelectric conversion units, an element isolation unit that performs element isolation between the plurality of photoelectric conversion units, a diffusion prevention unit that prevents diffusion of dark current component generated on an interfacial surface of the element isolation unit to a region surrounding the dark current component generation region, a first conductive type first region that is formed deeper than the bottom surface of the element isolation unit, covers the side wall of the element isolation unit on the photoelectric conversion unit side, and has impurity concentration higher than a first conductive type well region of the surrounding of the photoelectric conversion units, and a first conductive type third region that is formed along the bottom surface of the element isolation unit by separating by only a predetermined interval from the bottom surface in a depth direction with impurity concentration higher than the impurity concentration of the well region, the method comprising: implanting a first conductive type impurity that covers the side wall region of the element isolation unit into the region between the photoelectric conversion units and the element isolation unit, before formation of the element isolation unit or after the formation of the element isolation unit, and implanting the first conductive type impurity into an opening region of a mask which forms the element isolation unit, with an energy to set an injection range Rp to have a depth deeper than the element isolation unit. ### Claim 20 An electronic device comprising a solid-state imaging apparatus which includes a plurality of photoelectric conversion units, an element isolation unit that performs element isolation between the plurality of photoelectric conversion units, and a diffusion prevention unit that prevents diffusion of a dark current component generated on an interfacial surface of the element isolation unit to a region surrounding the dark current component generation region, as an imaging unit.