# US 9,753,364 B2 · Producing resist layers using fine segmentation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,753,364 B2 - Document ID: US9753364B2 - Status: Granted - Kind: B2 - Application number: 14/734,460 - Filed: 2015-06-09 - Published: 2015-09-24 - Granted: 2017-09-05 - Earliest claimed: 2013-07-15 - Assignees: KLA-Tencor Corporation - Applicants: Kla-Tencor Corporation - Inventors: Nuriel Amir - Web page: https://patentgrep.com/patent/US9753364B2 ## CPC - G03F 1/38: Masks having auxiliary features, e.g. special coatings or marks for alignment or testing; Preparation thereof - G03F 7/20: Exposure; Apparatus therefor (photographic printing apparatus for making copies G03B27/00) - G03F 7/70633: {Overlay, i.e. relative alignment between patterns printed by separate exposures in different layers, or in the same layer in multiple exposures or stitching} - G03F 7/70683: {Mark designs} - G06F 30/39: Circuit design at the physical level (physical level design for reconfigurable circuits G06F30/347) - Y10T 428/24802: Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.] - 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) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Methods of designing resist layers to enhance production accuracy, as well as respective layers, design files and metrology targets are disclosed. Continuous or uniform feature(s) adjacent to segmented feature(s) having a pitch and a critical dimension (CD), are configured by design to be segmented upon exposure at a same pitch and a smaller CD than the segmented feature(s), to yield respective unsegmented continuous feature(s) upon development of the exposed resist. The disclosed approach allows producing imaging and scatterometry targets which are compatible with device design rules and with optical constraints of the exposure system, without loss of contrast of the produced targets. The methods may be fine-tuned according to the specific characteristics of lithography tools which are used in the production. ## Claims ### Claim 1 A method comprising: designing, with a processor, a mask for the fabrication of a metrology target, wherein the mask includes a first segmented feature adjacent to a second segmented feature, wherein the first segmented feature includes segments having a pitch and a first critical dimension, wherein the second segmented feature includes segments having the pitch and a second critical dimension different than the first critical dimension, wherein the first critical dimension is selected such that the first segmented feature is developed as a segmented printed feature of the metrology target, wherein the second critical dimension is selected such that the second segmented feature is developed as a continuous feature of the metrology target. ### Claim 2 (depends on 1) The method of claim 1, further comprising: selecting the second critical dimension to be less than half the first critical dimension. ### Claim 3 (depends on 1) The method of claim 1, further comprising: determining the second critical dimension experimentally according to a production tool performance with respect to exposure and development parameters. ### Claim 4 (depends on 1) The method of claim 1, further comprising: configuring the metrology target as an imaging target. ### Claim 5 (depends on 1) The method of claim 1, further comprising: configuring the metrology target as a scatterometry target. ### Claim 6 (depends on 1) The method of claim 1, further comprising: designing the first segmented feature and the second segmented feature of the mask to be segmented along a short side of the first segmented feature and along a short side of the second segmented feature. ### Claim 7 (depends on 1) The method of claim 1, further comprising: designing the first segmented feature and the second segmented feature of the mask to be segmented along a long side of the first segmented feature and along a long side of the second segmented feature. ### Claim 8 (depends on 1) The method of claim 1, wherein the continuous printed feature comprises: at least one of a gap or a bar. ### Claim 9 A method comprising: designing, with a processor, a mask for the fabrication of a metrology target, a first segmented feature adjacent to a second segmented feature, wherein the first segmented feature includes segments having a pitch and a first critical dimension, wherein the second segmented feature includes segments having the pitch and a second critical dimension different than the first critical dimension; exposing a resist layer with an image of the mask; and developing the resist layer, wherein printed features associated with the first segmented feature develop as a segmented printed feature, wherein printed features associated with the second segmented feature develop as a continuous printed feature. ### Claim 10 A method comprising: designing, in a resist layer of a metrology target, at least one continuous feature, which is adjacent to at least one segmented feature having a pitch and a critical dimension, to have a same pitch and a same critical dimension with respect to the at least one segmented feature; exposing the resist layer; and applying a cutting mask to the resist layer to remove a designed segmentation of the at least one continuous feature. ### Claim 11 (depends on 1) A target design file, designed according to the method of claim 1. ### Claim 12 (depends on 11) A metrology target produced according to the target design file of claim 11. ### Claim 13 (depends on 12) Production equipment, configured to produce the metrology target of claim 12. ### Claim 14 An exposed resist layer, comprising: a continuous printed feature, which is adjacent to a segmented printed feature having a pitch and a first critical dimension, wherein the segmented printed feature corresponds to a first segmented feature of a pattern mask, wherein the continuous printed feature corresponds to a second segmented feature of the pattern mask, wherein the first segmented feature includes segments having the pitch and the first critical dimension, wherein the second segmented feature includes segments having the pitch and a second critical dimension different than the first critical dimension. ### Claim 15 (depends on 14) The exposed resist layer of claim 14, wherein the second critical dimension is less than half of the first critical dimension. ### Claim 16 (depends on 14) The exposed resist layer of claim 14, wherein the second critical dimension is determined experimentally according to a production tool performance with respect to exposure and development parameters. ### Claim 17 (depends on 14) The exposed resist layer of claim 14, wherein the exposed resist layer is configured to produce a respective layer of an imaging target. ### Claim 18 (depends on 14) The exposed resist layer of claim 14, wherein the exposed resist layer is configured to produce a respective layer of a scatterometry target. ### Claim 19 (depends on 14) The exposed resist layer of claim 14, wherein the first segmented feature and the second segmented feature are segmented along a short side of the first segmented feature and along a short side of the second segmented feature. ### Claim 20 (depends on 14) The exposed resist layer of claim 14, wherein the first segmented feature and the second segmented feature are segmented along a long side of the first segmented feature and along a long side of the second segmented feature. ### Claim 21 (depends on 14) The exposed resist layer of claim 14, wherein the at least one continuous feature comprises: at least one of a gap or a bar. ### Claim 22 (depends on 14) A metrology target produced using the exposed resist layer of claim 14. ### Claim 23 (depends on 22) Production equipment, configured to produce the metrology target of claim 22. ### Claim 24 (depends on 14) A mask designed to yield the exposed resist layer of claim 14. ### Claim 25 A mask, comprising: a first segmented feature adjacent to a second segmented feature, wherein the first segmented feature includes segments having a pitch and a first critical dimension, wherein the second segmented feature includes segments having the pitch and a second critical dimension different than the first critical dimension, wherein the first critical dimension is selected such that the first segmented feature is developed as a segmented printed feature, wherein the second critical dimension is selected such that the second segmented feature is developed as a continuous feature. ### Claim 26 (depends on 25) The mask of claim 25, wherein the second critical dimension is less than half the first critical dimension. ### Claim 27 (depends on 25) The mask of claim 25, wherein the second critical dimension is determined experimentally according to a production tool performance with respect to exposure and development parameters. ### Claim 28 (depends on 25) The mask of claim 25, configured to produce a respective layer of an imaging target. ### Claim 29 (depends on 25) The mask of claim 25, configured to produce a respective layer of a scatterometry target. ### Claim 30 (depends on 25) The mask of claim 25, wherein the first segmented feature and the second segmented feature are segmented along a short side of the first segmented feature and along a short side of the second segmented feature. ### Claim 31 (depends on 25) The mask of claim 25, wherein the first segmented feature and the second segmented feature are segmented along a long side of the first segmented feature and along a long side of the second segmented feature. ### Claim 32 (depends on 25) The mask of claim 25, wherein the at least one continuous feature comprises: at least one of a gap or a bar. ### Claim 33 (depends on 25) An exposed resist layer produced using the mask of claim 25. ### Claim 34 (depends on 25) A metrology target produced using the mask of claim 25. ### Claim 35 (depends on 34) Production equipment, configured to produce the metrology target of claim 34. ### Claim 36 A lithography system comprising: an illumination source; one or more projection optical elements; and a mask, wherein the one or more projection optical elements are configured to expose a sample with an image of the pattern mask based on illumination from the illumination source, wherein the mask includes a first segmented feature adjacent to a second segmented feature, wherein the first segmented feature includes segments having a pitch and a first critical dimension, wherein the second segmented feature includes segments having the pitch and a second critical dimension different than the first critical dimension, wherein the first critical dimension is selected such that the first segmented feature is developed as a segmented printed feature, wherein the second critical dimension is selected such that the second segmented feature is developed as a continuous feature.