# US 2025/0053096 A1 · Flexible Measurement Models For Model Based Measurements Of Semiconductor Structures > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0053096 A1 - Document ID: US20250053096A1 - Status: Published application - Kind: A1 - Application number: 18/231,181 - Filed: 2023-08-07 - Published: 2025-02-13 - Earliest claimed: 2023-08-07 - Assignees: KLA Corporation - Applicants: KLA Corporation - Inventors: Houssam Chouaib; Tianrong Zhan; Jonathan Iloreta; Teng Gu; Andrei V. Shchegrov - Web page: https://patentgrep.com/patent/US20250053096A1 ## CPC - 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 7/70625: {Dimensions, e.g. line width, critical dimension [CD], profile, sidewall angle or edge roughness} - G03F 7/706831: {Recipe selection or optimisation, e.g. select or optimise recipe parameters such as wavelength, polarisation or illumination modes} - 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 Methods and systems for generating measurement models of complex semiconductor structures based on re-useable, parametric models are presented herein. In some embodiments, the re-useable, parametric models enable measurement of high aspect ratio (HAR) structures having complex shape profiles. In these embodiments, a re-useable, parametric model includes multiple geometric sections each characterized by a different shape profile. Each shape profile is parameterized by at least one shape parameter. In a further aspect, at least one of the multiple geometric sections includes a plurality of subsections. In some other embodiments, the re-useable, parametric models enable measurement of nanowire based semiconductor structures. The re-useable, parametric models described herein are useful for generating measurement models for both optical metrology and x-ray metrology, e.g., soft x-ray metrology and hard x-ray metrology. The resulting measurement models yield more accurate measurement results with improved robustness. ## Claims ### Claim 1 A metrology system comprising: an illumination subsystem configured to illuminate a semiconductor structure with an amount of radiation at each of one or more measurement sites; a detector configured to detect an amount of measurement data associated with measurements of the semiconductor structure in response to the amount of radiation; and a computing system configured to: receive an indication of a selection of a re-useable, parametric model to describe at least a first portion of the semiconductor structure, wherein the re-useable, parametric model includes multiple geometric sections each characterized by a different shape profile parameterized by at least one shape parameter, wherein the re-useable, parametric model is fully defined by a set of independent parameters including the shape parameters characterizing the shape profiles of the multiple, geometric sections; receive an indication of a selection of initial values of the shape parameters associated with the shape profiles; and estimate a value of a parameter of interest characterizing the semiconductor structure at each of the one or more measurement sites based on a fitting of a measurement model to the amount of measurement data associated with each of the one or more measurement sites, wherein the measurement model includes the re-useable, parametric model. ### Claim 2 (depends on 1) The metrology system of claim 1, wherein at least one or the multiple geometric sections includes a plurality of subsections, each subsection characterized by a different shape profile parameterized by at least one shape parameter. ### Claim 3 (depends on 1) The metrology system of claim 1, wherein a first of the multiple geometric sections is parameterized by a first set of parameters and a second of the multiple geometric sections is parameterized by a second set of parameters, wherein the first set of parameters includes a different number of parameters than the second set of parameters. ### Claim 4 (depends on 1) The metrology system of claim 1, wherein a first of the multiple geometric sections is parameterized by a first set of parameters and a second of the multiple geometric sections is parameterized by a second set of parameters, wherein the first set of parameters includes the same number of parameters as the second set of parameters. ### Claim 5 (depends on 1) The metrology system of claim 1, wherein the semiconductor structure under measurement is a high aspect ratio structure, and wherein the parameter of interest is a critical dimension of the high aspect ratio structure. ### Claim 6 (depends on 5) The metrology system of claim 5, wherein the high aspect ratio structure under measurement includes at least 400 layers. ### Claim 7 (depends on 1) The metrology system of claim 1, wherein the semiconductor structure is fabricated on a wafer, and wherein the semiconductor structure is oriented in a direction normal to a planar surface of the wafer. ### Claim 8 (depends on 1) The metrology system of claim 1, wherein a height of each of the multiple geometric sections is characterized by a height ratio defined with respect to at least one of the other multiple geometric sections. ### Claim 9 (depends on 1) The metrology system of claim 1, wherein the illumination subsystem and the detector comprise an optical metrology system or an x-ray based metrology system. ### Claim 10 (depends on 1) The metrology system of claim 1, wherein the selection of the shape profiles associated with each of the multiple geometric sections and the selection of the initial values of the shape parameters associated with the shape profiles involves a trained library selection function based on a reference shape profile associated with the semiconductor structure under measurement. ### Claim 11 (depends on 1) The metrology system of claim 1, wherein the fitting of the measurement model to the amount of measurement data associated with each of the one or more measurement sites involves a regression on the values of the set of independent parameters. ### Claim 12 A method comprising: illuminating a semiconductor structure with an amount of radiation at each of one or more measurement sites; detecting an amount of measurement data associated with measurements of the semiconductor structure in response to the amount of radiation; receiving an indication of a selection of a re-useable, parametric model to describe at least a first portion of the semiconductor structure, wherein the re-useable, parametric model includes multiple geometric sections each characterized by a different shape profile parameterized by at least one shape parameter, wherein the re-useable, parametric model is fully defined by a set of independent parameters including the shape parameters characterizing the shape profiles of the multiple, geometric sections; receiving an indication of a selection of initial values of the shape parameters associated with the shape profiles; and estimating a value of a parameter of interest characterizing the semiconductor structure at each of the one or more measurement sites based on a fitting of a measurement model to the amount of measurement data associated with each of the one or more measurement sites, wherein the measurement model includes the re-useable, parametric model. ### Claim 13 (depends on 12) The method of claim 12, wherein at least one or the multiple geometric sections includes a plurality of subsections, each subsection characterized by a different shape profile parameterized by at least one shape parameter. ### Claim 14 (depends on 12) The method of claim 12, wherein a first of the multiple geometric sections is parameterized by a first set of parameters and a second of the multiple geometric sections is parameterized by a second set of parameters, wherein the first set of parameters includes a different number of parameters than the second set of parameters. ### Claim 15 (depends on 12) The method of claim 12, wherein the semiconductor structure under measurement is a high aspect ratio structure, and wherein the parameter of interest is a critical dimension of the high aspect ratio structure. ### Claim 16 (depends on 12) The method of claim 12, wherein a height of each of the multiple geometric sections is characterized by a height ratio defined with respect to at least one of the other multiple geometric sections. ### Claim 17 (depends on 12) The method of claim 12, wherein the selection of the shape profiles associated with each of the multiple geometric sections and the selection of the initial values of the shape parameters associated with the shape profiles involves a trained library selection function based on a reference shape profile associated with the semiconductor structure under measurement. ### Claim 18 (depends on 12) The method of claim 12, wherein the fitting of the measurement model to the amount of measurement data associated with each of the one or more measurement sites involves a regression on the values of the set of independent parameters. ### Claim 19 A metrology system comprising: an illumination subsystem configured to illuminate a semiconductor structure with an amount of radiation at each of one or more measurement sites; a detector configured to detect an amount of measurement data associated with measurements of the semiconductor structure in response to the amount of radiation; and a computing system configured to: receive an indication of a selection of a re-useable, parametric model to describe at least a portion of the semiconductor structure, wherein the re-useable, parametric model is fully defined by a set of independent parameter values, wherein the re-useable, parametric model describes a nanowire or nanosheet having any of a rounded square cross-section, a rounded trapazoid cross-section, a rounded diamond cross-section, and a rounded triangle cross-section; receive an indication of a selection of the set of independent parameter values; and estimate a value of a parameter of interest characterizing the semiconductor structure at each of the one or more measurement sites based on a fitting of a measurement model to the amount of measurement data associated with each of the one or more measurement sites, wherein the measurement model includes the re-useable, parametric model. ### Claim 20 (depends on 19) The metrology system of claim 19, wherein the re-useable, parametric model includes a uniform, conformal wrapper model or a non-uniform, conformal wrapper model.