# US 11,079,686 B2 · Excimer laser apparatus and electronic-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 11,079,686 B2 - Document ID: US11079686B2 - Status: Granted - Kind: B2 - Application number: 16/871,758 - Filed: 2020-05-11 - Published: 2020-08-27 - Granted: 2021-08-03 - Earliest claimed: 2017-12-05 - Assignees: Gigaphoton Inc. - Applicants: Gigaphoton Inc. - Inventors: Keisuke Ishida; Masato Moriya; Natsuhiko Kouno; Takeshi Asayama; Takashi Kusama - Web page: https://patentgrep.com/patent/US11079686B2 ## CPC - G01J 1/4257: {applied to monitoring the characteristics of a beam, e.g. laser beam, headlamp beam (monitoring arrangements for lasers in general H01S3/0014)} - G03F 7/70575: {Wavelength control, e.g. control of bandwidth, multiple wavelength, selection of wavelength or matching of optical components to wavelength} - G01J 3/26: using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters - G03F 7/70025: {by lasers} - H01S 3/036: Means for obtaining or maintaining the desired gas pressure within the tube, e.g. by gettering, replenishing; Means for circulating the gas, e.g. for equalising the pressure within the tube {(H01S3/031 takes precedence)} - H01S 3/104: in gas lasers - H01S 3/137: for stabilising of frequency - H01S 3/225: comprising an excimer or exciplex - H01S 3/08009: {using a diffraction grating} - H01S 3/08031: Single-mode emission - H01S 3/134: in gas lasers - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) - 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) - H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL ## Abstract An excimer laser apparatus according to the present disclosure includes an etalon spectrometer configured to measure a fringe waveform of a laser beam; and a controller configured to obtain area of a first ratio in a spectral space obtained based on a result of the measurement by the etalon spectrometer, calculate a first spectral line width of the laser beam based on the obtained area of the first ratio, and calibrate a first spectral line width based on a correlation function representing correlation between the first spectral line width and a second spectral line width of the laser beam measured by a reference meter. ## Claims ### Claim 1 An excimer laser apparatus comprising: an etalon spectrometer configured to measure a fringe waveform of a laser beam; and a controller configured to perform spectral-line-width measurement by obtaining an area of a first ratio in a total area of the fringe waveform, calculating a first spectral line width of the laser beam based on the obtained area of the first ratio, and calibrating the first spectral line width based on a correlation function representing a correlation between the first spectral line width and a second spectral line width of the laser beam measured by a reference meter, and perform update processing of the correlation function by performing deconvolution processing of a first spectral waveform obtained from the fringe waveform to calculate a second spectral waveform, calculating a third spectral line width based on the calculated second spectral waveform, and updating the correlation function based on a relation between the first spectral line width calibrated based on the correlation function and the third spectral line width. ### Claim 2 (depends on 1) The excimer laser apparatus according to claim 1, wherein the controller sets an area of a predetermined range with respect to a center position of the fringe waveform as the total area of the fringe waveform. ### Claim 3 (depends on 2) The excimer laser apparatus according to claim 2, wherein the controller sets a peak position of the fringe waveform as the center position of the fringe waveform. ### Claim 4 (depends on 2) The excimer laser apparatus according to claim 2, wherein the controller sets a center position of full width at half maximum of the fringe waveform as the center position of the fringe waveform. ### Claim 5 (depends on 2) The excimer laser apparatus according to claim 2, wherein the controller sets a barycenter of the fringe waveform as the center position of the fringe waveform. ### Claim 6 (depends on 1) The excimer laser apparatus according to claim 1, wherein the controller calculates the area of the first ratio by dividing the fringe waveform into a plurality of divided wavelength intervals, calculating a divided area of each divided wavelength interval, and integrating the divided areas. ### Claim 7 (depends on 1) The excimer laser apparatus according to claim 1, wherein the controller specifies a first waveform position at which an area integrated from a first end part of the fringe waveform has a second ratio in the total area, and a second waveform position at which an area integrated from a second end part of the fringe waveform has the second ratio, and calculates the first spectral line width by regarding an area between the first waveform position and the second waveform position in the fringe waveform as the area of the first ratio. ### Claim 8 (depends on 1) The excimer laser apparatus according to claim 1, wherein the first ratio is 95% of the total area. ### Claim 9 (depends on 1) The excimer laser apparatus according to claim 1, wherein the controller repeats the update processing of the correlation function. ### Claim 10 (depends on 1) The excimer laser apparatus according to claim 1, wherein the correlation function is an exponential function or a polynomial, the polynomial including at least two constants. ### Claim 11 (depends on 1) The excimer laser apparatus according to claim 1, wherein the correlation function includes a coefficient for calibrating a wavelength dependency. ### Claim 12 (depends on 1) The excimer laser apparatus according to claim 1, wherein the correlation function includes a coefficient for calibrating a spectrum asymmetry dependency. ### Claim 13 An electronic-device manufacturing method comprising: generating a laser beam by a laser system; the laser system including: an etalon spectrometer configured to measure a fringe waveform of the laser beam; and a controller configured to perform spectral-line-width measurement by obtaining an area of a first ratio in a total area of the fringe waveform, calculating a first spectral line width of the laser beam based on the obtained area of the first ratio, and calibrating the first spectral line width based on a correlation function representing correlation between the first spectral line width and a second spectral line width of the laser beam measured by a reference meter, and perform update processing of the correlation function by performing deconvolution processing of a first spectral waveform obtained from the fringe waveform to calculate a second spectral waveform, calculating a third spectral line width based on the calculated second spectral waveform, and updating the correlation function based on a relation between the first spectral line width calibrated based on the correlation function and the third spectral line width: outputting the laser beam to an exposure apparatus; and exposing a photosensitive substrate to the laser beam by the exposure apparatus to manufacture an electronic device. ### Claim 14 An excimer laser apparatus comprising: an etalon spectrometer configured to measure a fringe waveform of a laser beam with an image sensor; and a controller configured to obtain an area of a first ratio in a total area of the fringe waveform, calculate a first spectral line width of the laser beam based on the obtained area of the first ratio, and calibrate the first spectral line width based on a correlation function representing a correlation between the first spectral line width and a second spectral line width of the laser beam measured by a reference meter, wherein the controller calculates the area of the first ratio by dividing the fringe waveform into a plurality of divided wavelength intervals corresponding to a plurality of channels of the image sensor, calculating a divided area of each divided wavelength interval, and integrating the divided areas. ### Claim 15 (depends on 14) The excimer laser apparatus according to claim 14, wherein the image sensor is a line sensor including a plurality of photodiodes, the photodiodes being linearly arranged, and the channels are the photodiodes. ### Claim 16 (depends on 14) The excimer laser apparatus according to claim 14, wherein the correlation function is an exponential function or a polynomial, the polynomial including at least two constants. ### Claim 17 (depends on 14) The excimer laser apparatus according to claim 14, wherein the correlation function includes a coefficient for calibrating a wavelength dependency. ### Claim 18 (depends on 14) The excimer laser apparatus according to claim 14, wherein the correlation function includes a coefficient for calibrating a spectrum asymmetry dependency.