`Application No. To Be Assigned
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`Amendments to the Claims
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`This listing of claims will replace all prior versions, andlistings, of claims in the application.
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`1.-23.
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`(Canceled)
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`24.
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`(New) A measurement system, comprising:
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`a sensor apparatus;
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`an illumination system arrangedto illuminate the sensor apparatus with radiation, the
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`sensor apparatus comprising a patterned region arrangedto receive a radiation beam and to form a
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`plurality of diffraction beams, the diffraction beams being separated in a shearing direction;
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`the sensor apparatus comprising a radiation detector;
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`wherein the patterned region is arranged suchthat at least some of the diffraction
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`beamsform interference patterns on the radiation detector;
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`wherein the sensor apparatus comprisesa plurality of patterned regions, and
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`wherein pitches of the patterned regionsare different in adjacent patterned regions.
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`25.
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`(New) The measurement system of claim 24, wherein the measurementsystem is arranged
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`such that the interference patterns from adjacent patterned regionsat least partially overlap at the
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`radiation detector.
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`26.
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`(New) The measurement system of claim 24, wherein the pitches of alternating patterned
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`regions are the same.
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`Atty. Dkt. No. 3857.2990001
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`ASML Netherlands B.V.
`Application No. To Be Assigned
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`27.|(New) The measurement system of claim 24, wherein the pitches of the adjacent patterned
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`regions are not even numberinteger multiples.
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`28.|(New) The measurement system of claim 27, wherein the pitches of the adjacent patterned
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`regions are not integer multiples.
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`29.
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`(New) The measurement system of claim 24, wherein the plurality of patterned regions
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`comprise thirteen patterned regions.
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`30.
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`(New) The measurement system of claim 24, wherein the plurality of patterned regions are
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`positioned at odd and evenfield point locations.
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`31.
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`(New) The measurement system of claim 24, wherein the plurality of patterned regions
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`extend in an x direction and in a second direction orthogonalto the x direction.
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`32.
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`(New) The measurement system of claim 24, the measurement system further comprising:
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`a patterning device;
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`wherein the illumination system is arranged to illuminate the patterning device with
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`radiation, the patterning device comprisinga first patterned region arranged to receive the radiation
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`Atty. Dkt. No. 3857.2990001
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`ASML Netherlands B.V.
`Application No. To Be Assigned
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`beam and to form a plurality of first diffraction beams,the first diffraction beams being separated in
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`the shearing direction;
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`wherein the patterned region of the sensor apparatus comprises a second patterned
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`region;
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`the projection system being configured to project the first diffraction beams onto the
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`sensor apparatus, the second patterned region being arrangedto receivethefirst diffraction beams
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`from the projection system and to form a plurality of second diffraction beams from eachofthe first
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`diffraction beams suchthat the first and second patterned regions formaset;
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`wherein the first and second patterned regions in the set are matched by matchingthe pitches
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`of the first and second patterned regions in the shearing direction such that at least some of the
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`second diffraction beams formed from at least one ofthe first diffraction beamsare spatially
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`coherent with a second diffraction beam formed from at least one otherfirst diffraction beam to
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`form interference patterns on the radiation detector;
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`wherein the patterning device comprises a plurality of first patterned regions and the
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`sensor apparatus comprisesa plurality of second patterned regions such that there is a plurality of
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`sets, each set comprising one ofthe plurality of first patterned regions and oneofthe plurality of
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`second patterned regions, and
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`wherein the pitches ofthe first patterned regions are different in adjacent sets and/or the
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`pitches of the second patterned regionsare different in adjacent sets.
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`Atty. Dkt. No. 3857.2990001
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`33.|(New) The measurement system of claim 32, wherein the pitches ofthe first patterned
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`regions and the second patterned regionsin at least one ofthe plurality of sets are the same.
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`ASML Netherlands B.V.
`Application No. To Be Assigned
`
`34.
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`(New) The measurement system of claim 32, further comprising a positioning apparatus
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`configured to moveat least one of the patterning device and the sensor apparatus in the shearing
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`direction; and
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`a controller configuredto:
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`control the positioning apparatus so as to moveat least one of the first patterning device and
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`the sensor apparatus in the shearing direction such that an intensity of radiation received by each
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`part of the radiation detector varies as a function of the movementin the shearing direction so as to
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`form oscillating signals correspondingto the different pitches of the first patterned regions in
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`adjacent sets and/or the different pitches of the second patterned regions in adjacentsets;
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`determine from the radiation detector phases of harmonicsofthe oscillating signals at a
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`plurality of positions on the radiation detector; and
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`determine a set of coefficients that characterize an aberration map of the projection system
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`from the phase of the harmonicsofthe oscillating signals at the plurality of positions on the
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`radiation detector.
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`35.
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`(New) The measurement system of claim 34, wherein the set of coefficients that characterize
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`the aberration map ofthe projection system are determined by equating the phases of the harmonics
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`Atty. Dkt. No. 3857.2990001
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`ASML Netherlands B.V.
`Application No. To Be Assigned
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`of the oscillating signals to a difference in the aberration map betweenpositions in the pupil plane
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`that are separated in the shearing direction by twice a shearing distance which corresponds to the
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`distance in the pupil plane between two adjacentfirst diffraction beams and solvingto find the set
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`of coefficients.
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`36.
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`(New) The measurement system of claim 35, wherein the set of coefficients that characterize
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`the aberration map ofthe projection system are determined by simultaneously solving constraints
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`for the shearing direction and for a second, orthogonal direction.
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`37.
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`(New) The measurement system of claim 35, wherein the plurality of first patterned regions
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`and the plurality of second patterned regionsare gratings.
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`38.
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`(New)A lithographic apparatus comprising the measurementsystem of claim 32.
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`39.
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`(New) A method for measurement, the method comprising:
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`illuminating a sensor apparatus with radiation, wherein the sensor apparatus
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`comprises a patterned region arranged to receive at least a portion of the radiation and to form a
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`plurality of diffraction beams, the diffraction beams being separated in a shearing direction;
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`wherein the sensor apparatus comprises a radiation detector arranged to receive at
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`least a portion of the diffraction beams,
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`Atty. Dkt. No. 3857.2990001
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`ASML Netherlands B.V.
`Application No. To Be Assigned
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`wherein the patterned region is arranged suchthat at least some ofthe diffraction
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`beamsform interference patterns on the radiation detector;
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`wherein the sensor apparatus comprisesa plurality of patterned regions, and
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`wherein pitches of the patterned regionsare different in adjacent patterned regions.
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`40.
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`(New) The methodof claim 39, the method further comprising:
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`illuminating a patterning device with radiation, wherein the patterning device
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`comprisesa first patterned region arranged to receive at least a portion of the radiation and to form a
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`plurality of first diffraction beams,the first diffraction beams being separated in the shearing
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`direction;
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`projecting, with the projection system,at least part of the plurality offirst diffraction
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`beams onto the sensor apparatus comprising:
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`the patterned region comprising a second patterned region arranged to receive thefirst
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`diffraction beams from the projection system and to form a plurality of second diffraction beams
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`from eachofthe first diffraction beams; and
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`a radiation detector arranged to receive at least a portion of the second diffraction beams,
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`wherein the first and second patterned regions in the set are matched by matching the
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`pitches of the first and second patterned regions in the shearing direction such that at least some of
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`the second diffraction beams formed from at least one ofthe first diffraction beamsare spatially
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`Atty. Dkt. No. 3857.2990001
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`ASML Netherlands B.V.
`Application No. To Be Assigned
`
`coherent with a second diffraction beam formed from at least one otherfirst diffraction beam to
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`form interference patterns on the radiation detector;
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`wherein the patterning device comprises a plurality of first patterned regions and the
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`sensor apparatus comprisesa plurality of second patterned regions such that there is a plurality of
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`sets, each set comprising one ofthe plurality of first patterned regions and oneofthe plurality of
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`second patterned regions, and
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`wherein the pitches ofthe first patterned regions are different in adjacent sets and/or the
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`pitches of the second patterned regionsare different in adjacent sets.
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`Al.
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`(New) The method of claim 40, further comprising movingat least one of the patterning
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`device and the sensor apparatus in the shearing direction such that an intensity of radiation received
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`by each part of the radiation detector varies as a function of the movementin the shearing direction
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`so as to form a plurality of oscillating signals corresponding to the different pitches ofthe first
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`patterned regions in adjacent sets and/or the different pitches of the second patterned regionsin
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`adjacentsets;
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`determining from the radiation detector phases of harmonicsofthe oscillating signals
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`at a plurality of positions on the radiation detector; and
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`determining a set of coefficients that characterize an aberration map ofthe projection system
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`from the phase of the harmonicsofthe oscillating signals at the plurality of positions on the
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`radiation detector.
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`Atty. Dkt. No. 3857.2990001
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`ASML Netherlands B.V.
`Application No. To Be Assigned
`
`42.
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`(New) The method of claim 41, further comprising determiningthe set of coefficients that
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`characterize the aberration map ofthe projection system by equating the phases of the harmonics of
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`the oscillating signals to a difference in the aberration map between positions in the pupil plane that
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`are separated in the shearing direction by twice a shearing distance which corresponds to the
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`distance in the pupil plane between twoadjacentfirst diffraction beamsand solvingto find the set
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`of coefficients.
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`43.
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`(New) The method ofclaim 40, further comprising determining the set of coefficients that
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`characterize the aberration map ofthe projection system by simultaneously solving constraints for
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`the shearing direction and for a second, orthogonal direction.
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`Atty. Dkt. No. 3857.2990001
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