# US 7,745,067 B2 · Method for performing place-and-route of contacts and vias in technologies with forbidden pitch requirements > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,745,067 B2 - Document ID: US7745067B2 - Status: Granted - Kind: B2 - Application number: 11/191,078 - Filed: 2005-07-28 - Published: 2007-02-01 - Granted: 2010-06-29 - Earliest claimed: 2005-07-28 - Assignees: Texas Instruments Incorporated - Inventors: James Walter Blatchford; Scott William Jessen - Web page: https://patentgrep.com/patent/US7745067B2 ## CPC - G06F 30/39: Circuit design at the physical level (physical level design for reconfigurable circuits G06F30/347) - G03F 1/36: Masks having proximity correction features; Preparation thereof, e.g. optical proximity correction [OPC] design processes - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) ## Abstract Provide is a method of making a mask layout, an integrated circuit device made by a method, a computer readable medium, and a mask for forming contact holes. The method can comprise patterning a first feature along a first axis, determining a first set of areas adjacent to the first feature, wherein each of the areas in the first set of areas is within a first angle away from the first axis, and wherein each of the areas in the first set of areas is within a first distance away from the first feature, and patterning a second feature in at least one of the first set of areas so as to form a mask layout, wherein each of the first feature and the second feature are one of a virtual feature and a real feature. ## Claims ### Claim 1 A method of making a mask layout for forming contact holes on a semiconductor device, the method comprising: patterning a first feature along a first axis; determining a first set of areas adjacent to the first feature, wherein each of the areas in the first set of areas is within a first angle away from the first axis, and wherein each of the areas in the first set of areas is within a first distance away from the first feature; and patterning a second feature in at least one of the first set of areas so as to form a mask layout, wherein each of the first feature and the second feature are one of a virtual feature and a real feature. ### Claim 2 (depends on 1) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 1 further comprising: pattering the first feature along a second axis, and wherein each of the areas in the first set of areas adjacent to the first feature are within the first angle away from the second axis. ### Claim 3 (depends on 2) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 2 further comprising: determining a second set of areas adjacent to the second feature, wherein each of the areas in the second set of areas is within a second angle away from a third axis, wherein the third axis is parallel to one of the first axis and the second axis, and wherein each of the areas in the second set of areas is within a second distance away from the second feature; and patterning a third feature in at least one of the second set of areas, wherein the third feature is one of the virtual feature and the real feature. ### Claim 4 (depends on 3) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 3 further comprising: determining a third set of areas adjacent to the third feature, wherein each of the areas in the third set of areas is within a third angle away from a fourth axis, wherein the fourth axis is parallel to one of the first axis and the second axis, and wherein each of the areas in the third set of areas is within a third distance away from the third feature. ### Claim 5 (depends on 4) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 4 further comprising: patterning at least one of the real feature and the virtual feature in each of the areas in the first set of areas, the second set of areas, and the third set of areas. ### Claim 6 (depends on 2) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 2, wherein the second axis is orthogonal to the first axis. ### Claim 7 (depends on 1) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 1, wherein the first angle is between ±15 degrees. ### Claim 8 (depends on 1) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 1, wherein the first distance is from about 100 nm to about 200 nm. ### Claim 9 (depends on 2) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 2, wherein each of the first set of areas is from about 100 nm to about 200 nm away from the first target feature and is between ±15 degrees away from at least one of the first axis and the second axis. ### Claim 10 (depends on 4) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 4, wherein the first angle is substantially similar to the second angle, and wherein the second angle is substantially similar to the third angle. ### Claim 11 (depends on 4) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 4, wherein the first distance is substantially similar to the second distance, and wherein the second distance is substantially similar to the third distance. ### Claim 12 (depends on 4) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 4, wherein one of the first set of areas overlaps a portion of one of the third set of areas. ### Claim 13 (depends on 5) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 5, wherein a contact hole feature is placed in areas having real features. ### Claim 14 (depends on 13) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 13, wherein a sub-resolution assist feature is placed in areas having virtual features. ### Claim 15 (depends on 4) The method of making a mask layout for forming contact holes on a semiconductor device according to claim 4, wherein each of the areas has a shape of a truncated circle. ### Claim 16 A method of making a mask layout, the method comprising: positioning a plurality of features on a layout, wherein the plurality of features comprises a first feature, wherein the first feature is positioned along a first axis and a second axis orthogonal to the first axis, and a plurality of additional features, wherein each of the additional features is positioned on an axis parallel to the first axis and on an axis parallel to the second axis; determining a first set of areas adjacent to the first feature, wherein each of the areas in the first set of areas is defined by a distance (d1) to a distance (d2) away from the first feature and within a first angle away from one of the first axis and the second axis, and wherein each one of the areas in the first set of areas comprises one of the plurality of additional features; and patterning one of a contact hole feature and a sub-resolution assist feature (SRAF) in the position of the first feature and the additional features. ### Claim 17 (depends on 16) The method of making a mask layout according to claim 16 further comprising: determining additional sets of areas adjacent to each of the additional features, wherein each of the areas in the additional sets of areas is defined by the distance (d1) to the distance (d2) away from the corresponding additional feature and within the first angle away from one of the additional axis parallel to the first axis and the additional axis parallel to the second axis, and wherein each one of the areas in the additional set of areas comprises one of the plurality of additional features. ### Claim 18 (depends on 17) The method of making a mask layout according to claim 17, wherein the distance (d1) is about 100 nm and the distance (d2) is about 200 nm, and wherein the first angle is from ±15 degrees away from the corresponding axis. ### Claim 19 (depends on 17) The method of making a mask layout according to claim 17, wherein the second axis is orthogonal to the first axis. ### Claim 20 (depends on 16) The method of making a mask layout according to claim 16, wherein each of the areas has a shape of a truncated circle. ### Claim 21 (depends on 16) The method of making a mask layout according to claim 16 further comprising: storing the mask design on a computer readable medium. ### Claim 22 (depends on 16) The method of making a mask layout according to claim 16, wherein the method is done using a computer readable medium. ### Claim 23 A non-transitory computer readable storage medium containing executable program code stored thereon, wherein the program code instructs a processor to perform a method of making a mask layout for forming contact holes on a semiconductor device including the following steps: patterning a first feature along a first axis; determining a first set of areas adjacent to the first feature, wherein each of the areas in the first set of areas is within a first angle away from the first axis, and wherein each of the areas in the first set of areas is within a first distance away from the first feature; and patterning a second feature in at least one of the first set of areas so as to form a mask layout, wherein each of the first feature and the second feature are one of a virtual feature and a real feature. ### Claim 24 (depends on 23) The computer readable medium containing program code according to claim 23, wherein the program code instructs the processor to perform the method further including the following step: pattering the first feature along a second axis, wherein each of the areas in the first set of areas adjacent to the first feature are within the first angle away from the second axis. ### Claim 25 (depends on 24) The computer readable medium containing program code according to claim 24, wherein the program code instructs the processor to perform the method further including the following steps: determining a second set of areas adjacent to the second feature, wherein each of the areas in the second set of areas is within a second angle away from a third axis, wherein the third axis is parallel to one of the first axis and the second axis, and wherein each of the areas in the second set of areas is within a second distance away from the second feature; and patterning a third feature in at least one of the second set of areas, wherein the third feature is one of the virtual feature and the real feature. ### Claim 26 (depends on 25) The computer readable medium containing program code according to claim 25, wherein the program code instructs the processor to perform the method further including the following step: determining a third set of areas adjacent to the third feature, wherein each of the areas in the third set of areas is within a third angle away from a fourth axis, wherein the fourth axis is parallel to one of the first axis and the second axis, and wherein each of the areas in the third set of areas is within a third distance away from the third feature. ### Claim 27 (depends on 26) The computer readable medium containing program code according to claim 26, wherein the program code instructs the processor to perform the method further including the following step: patterning at least one of the real feature and the virtual feature in each of the areas in the first set of areas, the second set of areas, and the third set of areas. ### Claim 28 (depends on 23) The computer readable medium containing program code according to claim 23, wherein the first angle is between ±15 degrees. ### Claim 29 (depends on 23) The computer readable medium containing program code according to claim 23, wherein the first distance is from about 100 nm to about 200 nm. ### Claim 30 A mask for use in the manufacture of an integrated circuit, the mask comprising: a transparent substrate having a mask design, the mask design comprising, a first feature to be imaged on a substrate, wherein the first feature is positioned along a first axis and a second axis; and a second feature, wherein the second feature is positioned from about 100 nm to about 200 nm away from the first feature, and wherein the second feature is positioned from about ±15 degrees from one of the first axis and the second axis, and wherein the second feature is one of a sub-resolution assist feature and a feature to be imaged on the substrate. ### Claim 31 (depends on 30) The mask for use in the manufacture of an integrated circuit according to claim 30, wherein the second axis is orthogonal to the first axis. ### Claim 32 (depends on 30) The mask for use in the manufacture of an integrated circuit according to claim 30, wherein the first feature and the second feature form contact holes on the substrate.