# US 8,772,072 B2 · Backside illuminated image sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,772,072 B2 - Document ID: US8772072B2 - Status: Granted - Kind: B2 - Application number: 13/525,851 - Filed: 2012-06-18 - Published: 2012-10-04 - Granted: 2014-07-08 - Earliest claimed: 2007-12-05 - Assignees: Intellectual Ventures II LLC - Applicants: Sung-Gyu Pyo - Inventors: Sung-Gyu Pyo - Web page: https://patentgrep.com/patent/US8772072B2 ## CPC - H10F 39/026: {Wafer-level processing} - H10F 39/199: {Back-illuminated image sensors} - H10F 39/811: {Interconnections} - H10W 20/023: {the interconnections being through-semiconductor vias} - H10W 20/0245: {comprising use of blind vias during the manufacture} - H10W 20/20: Interconnections within wafers or substrates, e.g. through-silicon vias [TSV] - H10W 20/2134: {TSVs extending from the semiconductor wafer into back-end-of-line layers} - H10W 20/218: {in silicon-on-insulator [SOI] wafers} - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A backside illuminated image sensor includes a light receiving element disposed in a first substrate, an interlayer insulation layer disposed on the first substrate having the light receiving element, an align key spaced apart from the light receiving element and passing through the interlayer insulation layer and the first substrate, a plurality of interconnection layers disposed on the interlayer insulation layer in a multi-layered structure, wherein the backside of the lowermost interconnection layer is connected to the align key, a passivation layer covering the interconnection layers, a pad locally disposed on the backside of the first substrate and connected to the backside of the align key, a light anti-scattering layer disposed on the backside of the substrate having the pad, and a color filter and a microlens disposed on the light anti-scattering layer to face the light receiving element. ## Claims ### Claim 1 A method, comprising: forming a light-receiving element in a front side of a first substrate; forming a microlens on a back side of the first substrate; bonding, to the front side of the first substrate, a second substrate including circuitry configured to process signals from the light-receiving element; forming a plurality of interconnection layers between the first substrate and the second substrate; forming an align key that passes through the first substrate and that connects to the plurality of interconnection layers; grinding the back side of the first substrate to expose the align key; and forming a pad on the back side of the first substrate and on the align key. ### Claim 2 (depends on 1) The method of claim 1, further comprising forming a light anti-scattering layer on the back side of the substrate by stacking materials having different refractive indexes. ### Claim 3 (depends on 1) The method of claim 1, wherein said forming an align key comprises filling a via hole with a conductive material. ### Claim 4 A method, comprising: forming a light-receiving element in a front side of a first substrate; forming a microlens on a back side of the first substrate; bonding, to the front side of the first substrate, a second substrate including circuitry configured to process signals from the light-receiving element; forming a plurality of interconnection layers between the first substrate and the second substrate; forming an align key that passes through the first substrate and that connects to the plurality of interconnection layers; exposing the align key through the back side of the first substrate; and forming a pad on the back side of the first substrate and on the align key. ### Claim 5 (depends on 4) The method of claim 4, further comprising forming a light anti-scattering layer on the back side of the substrate by stacking materials having different refractive indexes. ### Claim 6 (depends on 4) The method of claim 4, wherein said forming an align key comprises filling a via hole with a conductive material. ### Claim 7 A method, comprising: forming a light-receiving element in a substrate; forming an interlayer insulation layer on a front side of the substrate; forming an align key spaced apart from the light-receiving element and through the interlayer insulation layer and the substrate; forming a plurality of interconnection layers on the interlayer insulation layer such that an interconnection layer from the plurality of interconnection layers is connected to the align key; forming a passivation layer on the plurality of interconnection layers; forming a pad on a back side of the substrate such that the pad is connected to the align key; and forming a light anti-scattering layer on the back side of the substrate. ### Claim 8 (depends on 7) The method of claim 7, wherein said forming a light anti-scattering layer comprises stacking materials having different refractive indexes to form the light anti-scattering layer as a multi-layered structure. ### Claim 9 (depends on 8) The method of claim 8, wherein said stacking comprises stacking an oxide layer and a nitride layer. ### Claim 10 (depends on 8) The method of claim 8, wherein said stacking comprises stacking an oxide layer and a carbon-containing layer. ### Claim 11 (depends on 7) The method of claim 7, wherein said forming an align key comprises filling a via hole with a conductive material. ### Claim 12 (depends on 7) The method of claim 7, further comprising bonding another substrate to the passivation layer. ### Claim 13 A method, comprising: forming a light-receiving element in a front side of a substrate; forming an interlayer insulation layer on the front side of the substrate; forming an align key spaced apart from the light-receiving element and through the interlayer insulation layer and the substrate; forming a plurality of interconnection layers on the interlayer insulation layer; and forming a microlens on a back side of the substrate such that the microlens is configured to direct light toward the light-receiving element. ### Claim 14 (depends on 13) The method of claim 13, further comprising forming a pad on the back side of the substrate such that the pad is connected to the align key. ### Claim 15 (depends on 13) The method of claim 13, wherein said forming an align key comprises filling a via hole with a conductive material that connects the pad to at least one interconnection layer from the plurality of interconnection layers. ### Claim 16 (depends on 13) The method of claim 13, further comprising forming additional align keys that pass through the interlayer insulation layer and that further connect the pad to the plurality of interconnection layers. ### Claim 17 (depends on 13) The method of claim 13, further comprising forming a pad on an exposed back side of the plurality of interconnection layers. ### Claim 18 (depends on 13) The method of claim 13, wherein said forming an align key comprises filling a via hole with an insulating material. ### Claim 19 (depends on 13) The method of claim 13, further comprising: forming source regions and drain regions in the substrate; and forming contact plugs that pass through the interlayer insulation layer and connect the source regions and drain regions to the plurality of interconnection layers. ### Claim 20 (depends on 13) The method of claim 13, further comprising bonding, to the front side of the substrate, another substrate that includes circuitry configured to process image signals from the substrate.