# US 2008/0186482 A1 · Inspection method and apparatus, lithographic apparatus, lithographic processing cell and device manufacturing method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0186482 A1 - Document ID: US20080186482A1 - Status: Published application - Kind: A1 - Application number: 11/701,516 - Filed: 2007-02-02 - Published: 2008-08-07 - Earliest claimed: 2007-02-02 - Assignees: ASML Netherlands B.V. - Inventors: Arie Jeffrey Den Boef; Stanislav Y. Smirnov; Adel Joobeur - Web page: https://patentgrep.com/patent/US20080186482A1 ## CPC - G03F 7/70625: {Dimensions, e.g. line width, critical dimension [CD], profile, sidewall angle or edge roughness} - 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 A scatterometer has a radiation source capable of emitting radiation in distinct first and second wavelength ranges. An adjustable optical element is provided to effect a chromatic correction as necessary according to which wavelength range is in use. A single scatterometer can thereby effect measurements using widely separated wavelengths. ## Claims ### Claim 1 An inspection apparatus configured to determine a value related to a parameter of a target pattern printed on a substrate by a lithographic process used to manufacture a device layer on a substrate, the apparatus comprising: a radiation source arranged to selectively emit a first beam of radiation having a first wavelength in a first wavelength range or a second beam of radiation having a second wavelength in a second wavelength range, the second wavelength range being distinct from the first wavelength range; an optical system arranged to direct the selected one of the first or second beams of radiation on to the target pattern and to project radiation redirected by the target pattern onto a detector to obtain a scatterometric spectra; and an adjustable optical element arranged to selectively effect a chromatic correction of the optical system according to whether the first or second beam of radiation is emitted by the radiation source. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the first wavelength range is 5 to 300 nm. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the second wavelength range is 400 to 800 nm. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the first beam of radiation comprises a plurality of components each having a respective wavelength in the first wavelength range. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the second beam of radiation comprises a plurality of components each having a respective wavelength in the second wavelength range. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the first beam of radiation is a broadband beam comprising a range of wavelengths in the first wavelength range. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the second beam of radiation is a broadband beam comprising a range of wavelengths in the second wavelength range. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the adjustable optical element comprises a deformable mirror. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein the adjustable optical element comprises an adjustable refractive lens element. ### Claim 10 (depends on 1) The apparatus of claim 1, wherein the adjustable optical element comprises a refractive lens element and an actuator arranged to adjust the position and/or orientation of the refractive lens element. ### Claim 11 (depends on 1) The apparatus of claim 1, wherein the adjustable optical element comprises a pair of refractive lens elements and an actuator arranged to adjust the relative position of the pair of refractive lens elements. ### Claim 12 (depends on 1) The apparatus of claim 1, wherein the adjustable optical element comprises a plurality of exchangeable optical elements and an actuator arranged to selectively position one of the exchangeable optical elements in the optical system. ### Claim 13 (depends on 1) The apparatus of claim 1, wherein the optical system comprises an illumination branch arranged to direct the selected one of the first or second beams of radiation on to the target pattern and a detection branch arranged to project radiation redirected by the target pattern onto a detector to obtain a scatterometric spectra, wherein the adjustable optical element is provided in the illumination branch. ### Claim 14 (depends on 1) The apparatus of claim 1, wherein the optical system comprises an illumination branch arranged to direct the selected one of the first or second beams of radiation on to the target pattern and a detection branch arranged to project radiation redirected by the target pattern onto a detector to obtain a scatterometric spectra, wherein the adjustable optical element is provided in the detection branch. ### Claim 15 (depends on 1) The apparatus of claim 1, wherein the optical system comprises an objective lens system and the adjustable optical element is provided in the objective lens system. ### Claim 16 (depends on 1) The apparatus of claim 1, wherein the adjustable optical element comprises a plurality of objective lens units selectively positionable in the optical system. ### Claim 17 A lithographic apparatus, comprising: an illumination optical system arranged to illuminate a pattern; a projection optical system arranged to project an image of the pattern on to a substrate; and an inspection apparatus configured to determine a value related to a parameter of a target pattern printed on a substrate by a lithographic process used to manufacture a device layer on a substrate, the apparatus comprising: an optical system arranged to direct a first beam of radiation having a first wavelength in a first wavelength range or a second beam of radiation having a second wavelength in a second wavelength range on to the target pattern and to project radiation redirected by the target pattern onto a detector to obtain a scatterometric spectra, the second wavelength range being distinct from the first wavelength range, and an adjustable optical element arranged to selectively effect a chromatic correction of the optical system according to whether the first or second beam of radiation is directed by the optical system. ### Claim 18 A lithographic cell comprising: a coater arranged to coat a substrate with a radiation sensitive layer; a lithographic apparatus arranged to expose an image onto the radiation sensitive layer of the substrate coated by the coater; a developer arranged to develop the image exposed by the lithographic apparatus; and an inspection apparatus configured to determine a value related to a parameter of a target pattern printed on a substrate by a lithographic process used to manufacture a device layer on a substrate, the apparatus comprising: a radiation source arranged to selectively emit a first beam of radiation having a first wavelength in a first wavelength range or a second beam of radiation having a second wavelength in a second wavelength range, the second wavelength range being distinct from the first wavelength range, an optical system arranged to direct the selected one of the first or second beams of radiation on to the target pattern and to project radiation redirected by the target pattern onto a detector to obtain a scatterometric spectra, and an adjustable optical element arranged to selectively effect a chromatic correction of the optical system according to whether the first or second beam of radiation is emitted by the radiation source. ### Claim 19 An inspection method to determine a value related to a parameter of a target pattern printed on a substrate by a lithographic process used to manufacture a device layer on a substrate, the method comprising: controlling a radiation source to selectively emit a first beam of radiation having a first wavelength in a first wavelength range or a second beam of radiation having a second wavelength in a second wavelength range, the second wavelength range being distinct from the first wavelength range; using an optical system to direct the selected one of the first or second beams of radiation on to the target pattern and to project radiation redirected by the target pattern onto a detector to obtain a scatterometric spectra; and adjusting an adjustable optical element to selectively effect a chromatic correction of the optical system according to whether the first or second beam of radiation is emitted by the radiation source. ### Claim 20 An inspection apparatus configured to determine a value related to a parameter of a target pattern printed on a substrate by a lithographic process used to manufacture a device layer on a substrate, the apparatus comprising: an optical system arranged to direct a first beam of radiation having a first wavelength in a first wavelength range or a second beam of radiation having a second wavelength in a second wavelength range, the second wavelength range being distinct from the first wavelength range, on to the target pattern and to project radiation redirected by the target pattern onto a detector to obtain a scatterometric spectra, the optical system comprising an objective lens having a pupil plane and arranged to collect the radiation redirected by the target pattern and an imaging optical system arranged to project an image of the pupil plane onto the detector; and an adjustable optical element arranged to selectively effect a chromatic correction of the optical system according to whether the first or second beam of radiation is directed by the optical system.