# US 8,788,982 B2 · Layout design defect repair using inverse lithography > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,788,982 B2 - Document ID: US8788982B2 - Status: Granted - Kind: B2 - Application number: 13/740,651 - Filed: 2013-01-14 - Published: 2013-07-25 - Granted: 2014-07-22 - Earliest claimed: 2005-02-28 - Assignees: Mentor Graphics Corporation - Applicants: Mentor Graphics Corporation - Inventors: George Lippincott; Yuri Granik; Sergey Kobelkov - Web page: https://patentgrep.com/patent/US8788982B2 ## CPC - G03F 1/70: Adapting basic layout or design of masks to lithographic process requirements, e.g., second iteration correction of mask patterns for imaging - G03F 1/36: Masks having proximity correction features; Preparation thereof, e.g. optical proximity correction [OPC] design processes - G03F 1/72: Repair or correction of mask defects - G06F 30/398: Design verification or optimisation, e.g. using design rule check [DRC], layout versus schematics [LVS] or finite element methods [FEM] (optical proximity correction [OPC] design processes G03F1/36) - 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) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Aspects of the invention relate to techniques for repairing layout design defects after layout data have been processed by resolution enhancement techniques. The repair process first determines a re-correction region that includes three portions: core, transition and visible portions. An inverse lithography process is then performed on the core and transition portions of the re-correction region while taking into account effects from the visible portion to generate a modified re-correction region. The transition portion is processed based on distance from boundary between the transition portion and the core portion such that layout features near the boundary between the transition portion and the core portion are adjusted more than layout features farther away from the boundary. ## Claims ### Claim 1 One or more non-transitory computer-readable media storing computer-executable instructions for causing one or more processors to perform a method, the method comprising: receiving information of an altered layout design and one or more errors detected in the altered layout design, the altered layout design generated by performing a resolution enhancement process on a layout design, the layout design representing at least a portion of an integrated circuit design; determining a re-correction region around at least one of the one or more detected errors, wherein the re-correction region designates a sub-portion of the altered layout design and includes three portions—core, transition and visible, wherein the core portion is enclosed by the transition portion and the transition portion is enclosed by the visible portion; performing an optical proximity correction process on the core portion of and the transition portion of the re-correction region while taking into account effects from the visible portion of the re-correction region to generate a modified re-correction region, wherein the transition portion is processed based on distance from boundary between the transition portion and the core portion such that layout features near the boundary between the transition portion and the core portion are adjusted more than layout features farther away from the boundary; saving information of the modified re-correction region to a memory storage location. ### Claim 2 (depends on 1) The one or more non-transitory computer-readable media recited in claim 1, wherein the optical proximity correction process is an inverse lithography process. ### Claim 3 (depends on 2) The one or more non-transitory computer-readable media recited in claim 2, wherein the inverse lithography process uses a weighted combination of a first gradient and a second gradient for the transition portion, wherein the weighting for the second gradient increases from zero at the boundary between the transition portion and the core portion to 100% at the boundary between the transition portion and the visible portion. ### Claim 4 (depends on 1) The one or more non-transitory computer-readable media recited in claim 1, wherein width of the visible region is based at least in part on optical diameter. ### Claim 5 (depends on 1) The one or more non-transitory computer-readable media recited in claim 1, wherein the method further comprises replacing the re-correction region in the altered layout design with the modified re-correction region. ### Claim 6 A method, comprising: with a computer, receiving information of an altered layout design and one or more errors detected in the altered layout design, the altered layout design generated by performing a resolution enhancement process on a layout design, the layout design representing at least a portion of an integrated circuit design; determining a re-correction region around at least one of the one or more detected errors, wherein the re-correction region designates a sub-portion of the altered layout design and includes three portions—core, transition and visible, wherein the core portion is enclosed by the transition portion and the transition portion is enclosed by the visible portion; performing an optical proximity correction process on the core portion of and the transition portion of the re-correction region while taking into account effects from the visible portion of the re-correction region to generate a modified re-correction region, wherein the transition portion is processed based on distance from boundary between the transition portion and the core portion such that layout features near the boundary between the transition portion and the core portion are adjusted more than layout features farther away from the boundary; saving information of the modified re-correction region to a memory storage location. ### Claim 7 (depends on 6) The method recited in claim 6, wherein the optical proximity correction process is an inverse lithography process. ### Claim 8 (depends on 7) The method recited in claim 7, wherein the inverse lithography process uses a weighted combination of a first gradient and a second gradient for the transition portion, wherein the weighting for the second gradient increases from zero at the boundary between the transition portion and the core portion to 100% at the boundary between the transition portion and the visible portion. ### Claim 9 (depends on 6) The method recited in claim 6, wherein width of the visible region is based at least in part on optical diameter. ### Claim 10 (depends on 6) The method recited in claim 6, further comprising: replacing the re-correction region in the altered layout design with the modified re-correction region. ### Claim 11 A system comprising: receiving information of an altered layout design and one or more errors detected in the altered layout design, the altered layout design generated by performing a resolution enhancement process on a layout design, the layout design representing at least a portion of an integrated circuit design; determining a re-correction region around at least one of the one or more detected errors, wherein the re-correction region designates a sub-portion of the altered layout design and includes three portions—core, transition and visible, wherein the core portion is enclosed by the transition portion and the transition portion is enclosed by the visible portion; performing an optical proximity correction process on the core portion of and the transition portion of the re-correction region while taking into account effects from the visible portion of the re-correction region to generate a modified re-correction region, wherein the transition portion is processed based on distance from boundary between the transition portion and the core portion such that layout features near the boundary between the transition portion and the core portion are adjusted more than layout features farther away from the boundary; saving information of the modified re-correction region to a memory storage location. ### Claim 12 (depends on 11) The system recited in claim 11, wherein the optical proximity correction process is an inverse lithography process. ### Claim 13 (depends on 12) The system recited in claim 12, wherein the inverse lithography process uses a weighted combination of a first gradient and a second gradient for the transition portion, wherein the weighting for the second gradient increases from zero at the boundary between the transition portion and the core portion to 100% at the boundary between the transition portion and the visible portion. ### Claim 14 (depends on 11) The system recited in claim 11, wherein width of the visible region is based at least in part on optical diameter. ### Claim 15 (depends on 11) The system recited in claim 11, wherein the method further comprises replacing the re-correction region in the altered layout design with the modified re-correction region.