# US 2026/0219593 A1 · Lithographic apparatus, inspection system, and method of implementing parallel sensor-heads with a common radiation source > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2026/0219593 A1 - Document ID: US20260219593A1 - Status: Published application - Kind: A1 - Application number: 19/152,840 - Filed: 2024-01-26 - Published: 2026-07-30 - Earliest claimed: 2023-02-23 - Assignees: ASML Netherlands B.V. - Applicants: ASML Netherlands B.V. - Inventors: Arjan Johannes Anton BEUKMAN; Henricus Petrus Maria PELLEMANS - Web page: https://patentgrep.com/patent/US20260219593A1 ## CPC - G03F 7/706843: {Metrology apparatus} - G03F 9/7065: {Production of alignment light, e.g. light source, control of coherence, polarization, pulse length, wavelength} - G01B 11/272: {using photoelectric detection means} - G03F 7/70605: {Workpiece metrology} - G03F 7/706849: {Irradiation branch, e.g. optical system details, illumination mode or polarisation control} - G03F 7/706851: {Detection branch, e.g. detector arrangements, polarisation control, wavelength control or dark/bright field detection} - G03F 9/7003: {Alignment type or strategy, e.g. leveling, global alignment} - G03F 9/7046: {Strategy, e.g. mark, sensor or wavelength selection} - G03F 9/7088: {Alignment mark detection, e.g. TTR, TTL, off-axis detection, array detector, video detection} - 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) - G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS ## Abstract A lithographic apparatus includes an illumination system, a projection system, and an inspection system. The inspection system includes a broadband radiation system, an optical system, wavelength separator system, and detector system. The broadband radiation system generates source radiation having a first set of narrowband wavelengths distributed within an operating bandwidth of the inspection system and a second set of narrowband wavelengths distributed within the operating bandwidth. A narrowband wavelength of the first set is proximal to a narrowband wavelength of the second set. The optical system directs first and second portions of the source radiation toward first and second targets to generate first and second scattered radiation. The wavelength separator system separates narrowband wavelengths of the first and second scattered radiation. The detector system receives the first and second scattered radiation to generate first and second measurement signals based on the first and second scattered radiation. ## Claims ### Claim 1 A lithographic apparatus comprising: an illumination system configured to illuminate a pattern of a patterning device; a projection system configured to project an image of the pattern onto a substrate to form a plurality of targets on the substrate; and an inspection system configured to inspect the plurality of targets, the inspection system comprising: a broadband radiation system configured to generate source radiation having a first set of narrowband wavelengths distributed within an operating bandwidth of the inspection system and a second set of narrowband wavelengths distributed within the operating bandwidth, wherein a narrowband wavelength of the first set is proximal to a narrowband wavelength of the second set; an optical system configured to direct a first portion of the source radiation toward a first target of the plurality of targets to generate first scattered radiation and to direct a second portion of the source radiation toward a second target of the plurality of targets to generate second scattered radiation; a wavelength separator system configured to separate narrowband wavelengths of the first and second scattered radiation; and a detector system configured to receive the first and second scattered radiation and to generate first and second measurement signals based on the first and second scattered radiation, respectively. ### Claim 2 (depends on 1) The lithographic apparatus of claim 1, wherein the broadband radiation system comprises a filter system configured to transmit the first set of narrowband wavelengths toward the first target and the second set of narrowband wavelengths toward the second target. ### Claim 3 (depends on 1) The lithographic apparatus of claim 1, wherein: the plurality of targets comprises a third target configured to generate third scattered radiation; and the broadband radiation system comprises a filter system configured to: transmit a portion of the first set of narrowband wavelengths toward the first target, transmit another portion of the first set of narrowband wavelengths toward the second target, and transmit at least a portion of the second set of narrowband wavelengths toward the third target to generate the third scattered radiation; and the detector system is further configured to receive the third scattered radiation and to generate a third measurement signal based on the third scattered radiation. ### Claim 4 (depends on 1) The lithographic apparatus of claim 1, wherein the operating bandwidth is approximately 1600 nm or less. ### Claim 5 (depends on 1) The lithographic apparatus of claim 1, wherein the narrowband wavelength of the first set is offset from the narrowband wavelength of the second set by approximately 5 to 15 nm. ### Claim 6 (depends on 1) The lithographic apparatus of claim 1, wherein the wavelength separator comprises a demultiplexer system comprising a dispersive device, a grating, dichroic mirror, and/or a filter. ### Claim 7 (depends on 1) The lithographic apparatus of claim 1, wherein the inspection system further comprises an optical fiber system configured to direct the first and second scattered radiation toward the detector system. ### Claim 8 (depends on 1) The lithographic apparatus of claim 1, wherein the source radiation comprises coherent radiation. ### Claim 9 (depends on 1) The lithographic apparatus of claim 1, wherein the first and second set of narrowband wavelengths are generated simultaneously by the broadband radiation system. ### Claim 10 An inspection system comprising: a broadband radiation system configured to generate source radiation having a first set of narrowband wavelengths distributed within an operating bandwidth of the inspection system and a second set of narrowband wavelengths distributed within the operating bandwidth, wherein a narrowband wavelength of the first set is proximal to a narrowband wavelength of the second set; an optical system configured to direct a first portion of the source radiation toward a first target of a plurality of targets to generate first scattered radiation and to direct a second portion of the source radiation toward a second target of the plurality of targets to generate second scattered radiation; a wavelength separator system configured to separate narrowband wavelengths of the first and second scattered radiation; and a detector system configured to receive the first and second scattered radiation and to generate first and second measurement signals based on the first and second scattered radiation, respectively. ### Claim 11 (depends on 10) The inspection system of claim 10, wherein the broadband radiation system comprises a filter system configured to transmit the first set of narrowband wavelengths toward the first target and the second set of narrowband wavelengths toward the second target. ### Claim 12 (depends on 10) The inspection system of claim 10, wherein: the plurality of targets comprises a third target configured to generate third scattered radiation; and the broadband radiation system comprises a filter system configured to: transmit a portion of the first set of narrowband wavelengths toward the first target, transmit another portion of the first set of narrowband wavelengths toward the second target, and transmit at least a portion of the second set of narrowband wavelengths toward the third target to generate the third scattered radiation; and the detector system is further configured to receive the third scattered radiation and to generate a third measurement signal based on the third scattered radiation. ### Claim 13 (depends on 10) The inspection system of claim 10, wherein the operating bandwidth is approximately 1600 nm or less. ### Claim 14 (depends on 10) The inspection system of claim 10, wherein the narrowband wavelength of the first set is offset from the narrowband wavelength of the second set by approximately 5 to 15 nm. ### Claim 15 (depends on 10) The inspection system of claim 10, wherein the wavelength separator comprises a demultiplexer system comprising a dispersive device, a grating, dichroic mirror, and/or a filter.