# US 10,770,602 B1 · Optical sensor and method for forming the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,770,602 B1 - Document ID: US10770602B1 - Status: Granted - Kind: B1 - Application number: 16/280,281 - Filed: 2019-02-20 - Published: 2020-08-20 - Granted: 2020-09-08 - Earliest claimed: 2019-02-20 - Assignees: Vanguard International Semiconductor Corporation - Applicants: Vanguard International Semiconductor Corporation - Inventors: Hsin-Hui Lee; Han-Liang Tseng; Jiunn-Liang Yu; Kwang-Ming Lin; Yin Chen; Si-Twan Chen; Hsueh-Jung Lin; Wen-Chih Lu; Ting-Jung Lu - Web page: https://patentgrep.com/patent/US10770602B1 ## CPC - H10F 39/8067: {Reflectors} - H10F 77/413: {directly associated or integrated with the devices, e.g. back reflectors (directly associated or integrated with photovoltaic cells H10F77/42)} - H10F 39/024: {of coatings or optical elements} - H10F 39/8057: {Optical shielding} - H10F 77/334: {for shielding light, e.g. light blocking layers or cold shields for infrared detectors} - H10F 39/107: {having multiple elements covered by H10F30/00 in a repetitive configuration, e.g. radiation detectors comprising photodiode arrays} - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION ## Abstract An optical sensor includes pixels disposed in a substrate and a light collimating layer disposed on the substrate. The light collimating layer includes a first light-shielding layer, first transparent pillars, a second light-shielding layer, and second transparent pillars. The first light-shielding layer is disposed on the substrate. The first transparent pillars through the first light-shielding layer are correspondingly disposed on the pixels. The second light-shielding layer is disposed on the first light-shielding layer and the first transparent pillars. The second transparent pillars through the second light-shielding layer are correspondingly disposed on the first transparent pillars. The top surface area of each of the first transparent pillars is not equal to the bottom surface area of each of the second transparent pillars. ## Claims ### Claim 1 An optical sensor, comprising: a plurality of pixels disposed in a substrate; a light collimating layer disposed on the substrate, comprising: a first light-shielding layer disposed on the substrate; a plurality of first transparent pillars through the first light-shielding layer correspondingly disposed on the pixels; a second light-shielding layer disposed on the first light-shielding layer and the first transparent pillars; and a plurality of second transparent pillars through the second light-shielding layer correspondingly disposed on the first transparent pillars, wherein a top surface area of each of the first transparent pillars is not equal to a bottom surface area of each of the second transparent pillars, wherein each of the first transparent pillars and the second transparent pillars has a total aspect ratio of between 1:1 and 30:1. ### Claim 2 (depends on 1) The optical sensor as claimed in claim 1, wherein the first transparent pillars and the second transparent pillars have a same cross-sectional shape. ### Claim 3 (depends on 1) The optical sensor as claimed in claim 1, wherein the first transparent pillars and the second transparent pillars have a different cross-sectional shape. ### Claim 4 (depends on 1) The optical sensor as claimed in claim 1, wherein the first transparent pillars and the second transparent pillars have a same cross-sectional size. ### Claim 5 (depends on 1) The optical sensor as claimed in claim 1, wherein the first transparent pillars and the second transparent pillars have a different cross-sectional size. ### Claim 6 (depends on 1) The optical sensor as claimed in claim 1, wherein a bottom surface area of each of the first transparent pillars and each of the second transparent pillars is not equal to a top surface area of each of the first transparent pillars and each of the second transparent pillars. ### Claim 7 (depends on 1) The optical sensor as claimed in claim 1, wherein a bottom surface area of each of the first transparent pillars and each of the second transparent pillars is equal to a top surface area of each of the first transparent pillars and each of the second transparent pillars. ### Claim 8 (depends on 1) The optical sensor as claimed in claim 1, wherein a sidewall of each of the first transparent pillars and each of the second transparent pillars is not perpendicular to a bottom surface of each of the first transparent pillars and each of the second transparent pillars. ### Claim 9 (depends on 1) The optical sensor as claimed in claim 1, wherein a sidewall of each of the first transparent pillars and each of the second transparent pillars is perpendicular to a bottom surface of each of the first transparent pillars and each of the second transparent pillars. ### Claim 10 (depends on 1) The optical sensor as claimed in claim 1, wherein the first transparent pillars and the second transparent pillars are made of the same material, and the first light-shielding layer and the second light-shielding layer are made of the same material. ### Claim 11 (depends on 1) The optical sensor as claimed in claim 1, further comprising: a bottom light-shielding layer disposed below the first light-shielding layer and above the substrate between the pixels. ### Claim 12 (depends on 11) The optical sensor as claimed in claim 11, wherein the bottom light-shielding layer is made of a different material than the first light-shielding layer and the second light-shielding layer. ### Claim 13 (depends on 1) The optical sensor as claimed in claim 1, further comprising: a first dummy transparent pillar through the first light-shielding layer disposed on the substrate in a peripheral region of the light collimating layer and not corresponded to any of the pixels; and a second dummy transparent pillar through the second light-shielding layer correspondingly disposed on the first dummy transparent pillar. ### Claim 14 (depends on 1) A method for forming the optical sensor as set forth in claim 1, comprising: forming a plurality of pixels in a substrate; forming a light collimating layer on the substrate, wherein forming of the light collimating layer comprises: forming a plurality of first transparent pillars on the substrate, wherein the first transparent pillars are correspondingly disposed on the pixels; forming a first light-shielding layer between the first transparent pillars; planarizing a top surface of the first transparent pillars and the first light-shielding layer; forming a plurality of second transparent pillars on the first transparent pillars and the first light-shielding layer, wherein the second transparent pillars are correspondingly disposed on the first transparent pillars; forming a second light-shielding layer between the second transparent pillars; and planarizing a top surface of the second transparent pillars and the second light-shielding layer, wherein a top surface area of each of the first transparent pillars is not equal to a bottom surface area of each of the second transparent pillars. ### Claim 15 (depends on 14) The method for forming an optical sensor as claimed in claim 14, wherein each of the first transparent pillars and the second transparent pillars has a total aspect ratio of between 1:1 and 30:1. ### Claim 16 (depends on 14) The method for forming an optical sensor as claimed in claim 14, wherein the first transparent pillars and the second transparent pillars are made of the same material, and the first light-shielding layer and the second light-shielding layer are made of the same material. ### Claim 17 (depends on 14) The method for forming an optical sensor as claimed in claim 14, further comprising: forming a bottom light-shielding layer on the substrate between the pixels, wherein the bottom light-shielding layer is disposed under the first light-shielding layer. ### Claim 18 (depends on 17) The method for forming an optical sensor as claimed in claim 17, wherein the bottom light-shielding layer is made of a different material than the first light-shielding layer and the second light-shielding layer. ### Claim 19 (depends on 14) The method for forming an optical sensor as claimed in claim 14, further comprising: forming a first dummy transparent pillar in a peripheral region of the light collimating layer, wherein the first dummy transparent pillar does not correspond to any of the pixels; and forming a second dummy transparent pillar correspondingly disposed on the first dummy transparent pillar.