# US 11,614,690 B2 · Methods of tuning process models > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,614,690 B2 - Document ID: US11614690B2 - Status: Granted - Kind: B2 - Application number: 16/478,489 - Filed: 2018-01-24 - Published: 2019-12-05 - Granted: 2023-03-28 - Earliest claimed: 2017-01-26 - Assignees: ASML Netherlands B.V. - Applicants: Asml Netherlands B.V. - Inventors: Mu Feng; Mir Farrokh Shayegan Salek; Dianwen Zhu; Leiwu Zheng; Rafael C. Howell; Jen-Shiang Wang - Web page: https://patentgrep.com/patent/US11614690B2 ## CPC - G03F 7/705: {Modelling or simulating from physical phenomena up to complete wafer processes or whole workflow in wafer productions} - G03F 7/70441: {Optical proximity correction [OPC]} - G05B 19/41875: {characterised by quality surveillance of production} - G05B 2219/33286: Test, simulation analysator - G05B 2219/45028: Lithography - G05B 2219/49087: Adjust parameter to compensate path deviation - 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) - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) ## Abstract Methods of constructing a process model for simulating a characteristic of a product of lithography from patterns produced under different processing conditions. The methods use a deviation between the variation of the simulated characteristic and the variation of the measured characteristic to adjust a parameter of the process model. ## Claims ### Claim 1 A method comprising: obtaining simulated characteristics by simulating, by a hardware computer system and under a plurality of processing conditions, characteristics of a product of lithography using a process model comprising a parameter; determining a statistical variation of the simulated characteristics; obtaining measured characteristics by measuring the characteristics of the product, from patterns produced under the plurality of processing conditions; determining a statistical variation of the measured characteristics; determining a first deviation between the statistical variation of the simulated characteristics and the statistical variation of the measured characteristics; and adjusting the parameter based on the first deviation. ### Claim 2 (depends on 1) The method of claim 1, further comprising adjusting a processing condition of manufacturing based on simulation by the process model. ### Claim 3 (depends on 1) The method of claim 1, further comprising selecting a group of locations for inspection on a substrate processed using the lithography based on simulation by the process model. ### Claim 4 (depends on 1) The method of claim 1, wherein the plurality of processing conditions are selected randomly. ### Claim 5 (depends on 1) The method of claim 1, wherein the plurality of processing conditions comprise a nominal processing condition. ### Claim 6 (depends on 1) The method of claim 1, wherein the statistical variation of the measured characteristics is selected from a group consisting of a standard deviation of the measured characteristics, a variance of the measured characteristics, and a range of the measured characteristics. ### Claim 7 (depends on 1) The method of claim 1, wherein the statistical variation of the simulated characteristics is selected from a group consisting of a standard deviation of the simulated characteristics, a variance of the simulated characteristics, and a range of the simulated characteristics. ### Claim 8 (depends on 1) The method of claim 1, wherein adjusting the parameter comprises determining a value of the parameter that causes a function of the first deviation to be at a local or global extremum. ### Claim 9 (depends on 1) The method of claim 1, wherein adjusting the parameter is based on a combination of the first deviation, and a second deviation between the simulated characteristics and the measured characteristics under a same processing condition. ### Claim 10 (depends on 1) The method claim 1, wherein the plurality of processing conditions comprise a characteristic of an illumination of patterning device by a lithographic apparatus, a characteristic of projection optics of a lithographic apparatus, and/or a characteristic of a patterning device with an arrangement of features thereon that represent a design layout. ### Claim 11 (depends on 1) The method of claim 1, wherein the characteristics of the product comprise a characteristic of an image. ### Claim 12 (depends on 1) The method of claim 1, wherein the characteristics of the product comprise a process window of a feature of a design layout. ### Claim 13 (depends on 1) The method of claim 1, wherein the characteristics of the product comprise a statistical parameter of a feature at a plurality of locations. ### Claim 14 A method comprising: obtaining a plurality of first deviations, each of which being between a statistical variation of simulated characteristics of a product of lithography and a statistical variation of measured characteristics of the product of lithography, wherein the simulated characteristics are obtained by simulating, by a hardware computer system, characteristics of the product using a process model comprising a parameter; constructing a plurality of cost functions, the cost functions being combinations of the plurality of first deviations; and adjusting the parameter of the process model by using the cost functions. ### Claim 15 (depends on 14) The method of claim 14, further comprising adjusting a processing condition of manufacturing based on simulation by the process model. ### Claim 16 A non-transitory computer-readable medium comprising instructions therein, the instructions, upon execution by a computer system, configured to cause the computer system to at least: obtain a plurality of first deviations, each of which being between a statistical variation of simulated characteristics of a product of lithography and a statistical variation of measured characteristics of the product of lithography, wherein the simulated characteristics are obtained by simulating, by a hardware computer system, characteristics of the product using a process model comprising a parameter; construct a plurality of cost functions, the cost functions being combinations of the plurality of first deviations; and adjust the parameter of the process model by using the cost functions. ### Claim 17 A non-transitory computer-readable medium comprising instructions therein, the instructions, upon execution by a computer system, configured to cause the computer system to at least: obtain simulated characteristics by computer simulation, under a plurality of processing conditions, of characteristics of a product of lithography using a process model comprising a parameter; determine a statistical variation of the simulated characteristics; obtain measured characteristics by measuring the characteristics of the product, from patterns produced under the plurality of processing conditions; determine a statistical variation of the measured characteristics; determine a deviation between the statistical variation of the simulated characteristics and the statistical variation of the measured characteristics; and adjust the parameter based on the deviation. ### Claim 18 (depends on 17) The computer-readable medium of claim 17, wherein the instructions are further configured to cause the computer system to adjust a processing condition of manufacturing based on simulation by the process model. ### Claim 19 (depends on 17) The computer-readable medium of claim 17, wherein the instructions are further configured to cause the computer system to select a group of locations for inspection on a substrate processed using the lithography based on simulation by the process model. ### Claim 20 (depends on 17) The computer-readable medium of claim 17, wherein the plurality of processing conditions are selected randomly.