Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
DETAILED ACTION
Amendment
The amendment filed on 01/07/2026 has been entered into this application. Claims 2 and 15 are cancelled.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1, 3-14 and 16-30 is/are rejected under 35 U.S.C. 103 as being unpatentable over Manassen et al. (2023/00314319 A1, previously cited reference) in view of Swillam et al. (2021/0095957 A1, previously cited reference), and further in view of Riley et al. (2003/0016882 A1).
Regarding claims 1, 14 and 27, Manassen discloses an overlay metrology system/method (claim 27) (figs. 1-9; overlay metrology tool 102) comprising:
an illumination sub-system illumination sub-system 106 [par. 0052, 0062] comprising:
one or more illumination sources illumination source 128 configured to generate one or more illumination beams illumination beam 108 [pars. 0052-53]; and
one or more illumination optics illumination lenses 130/illumination control optics 134 configured to direct the one or more illumination beams to
an overlay target overlay target 202 and/or grating-over-grating structures on a sample 104 as the sample is scanned along a stage-scan direction (i.e. x direction) by a translation stage translation stage 116 when implementing a metrology recipe/ program instructions executable by the associated one or more processors 124, wherein the overlay target overlay target 202 and/or grating-over-grating structures in accordance with the metrology recipe includes a plurality of measurement cells (i.e. one or more cells having a grating-over-grating structure with periodicity along a measurement direction)[pars. 0006-8, 0054-55], wherein each measurement cell includes a grating-over-grating structures including a first-layer grating feature on a first layer of the sample and a second-layer grating feature on a second layer of the sample in an overlapping region [pars. 0005-8], wherein the first-layer grating feature and the second-layer grating feature have a common whole pitch grating-over-grating structures [pars. 0006-8] [pars. 0047-76, 0057, 0060, 0073];
a collection sub-system collection sub-system 110 comprising:
plurality of detectors and/or at least two photodetectors 112 positioned in a collection pupil plane 114 at locations of overlap between the 0-order diffraction and the +/−1 diffraction orders includes a first photodetector located in a pupil plane at a location of overlap between 0-order diffraction from the overlay target and +1-order diffraction from the overlay target; and a second photodetector located in a pupil plane at a location of overlap between 0-order diffraction from the overlay target and -1-order diffraction from the overlay target [pars. 0053, 0067, 0102]; and
one or more collection optics one or more collection lenses 140 and/or collection control optics 142 [pars. 0047-82, 0102]; and
a controller 122 communicatively coupled to the first photodetector and the second photodetector included in the plurality of detectors and/or at least two photodetectors 112, the controller including one or more processors one or more processors 124 configured to execute program instructions causing the one or more processors to:
receive time-varying interference signals from the first photodetector and the second photodetector as the overlay target is scanned along the stage-scan direction [pars. 0067-0098, 0089-90, 0092-95];
the one or more processors 124 determine one or more differential signals between the first photodetector and the second photodetector included in the plurality of detectors and/or at least two photodetectors 112 for each measurement cell of the plurality of measurement cells (i.e. one or more cells having a grating-over-grating structure with periodicity along a measurement direction) [pars. 0006-8]; and determine an overlay measurement based on the determined one or more differential signals (see abstract) [pars. 0067-0098, 0089-90, 0092-95] [pars. 0043, 0046, 0067-0100].
Manassen also teaches that the systems and/or measurements may be calibrated to increase measurement accuracy [par. 0041], and that the controller 122 may calibrate or otherwise modify the overlay measurement based on known, assumed, or measured features of the sample that may also impact the time-varying interference signals such as, but not limited to, sidewall angles or other sample asymmetries [par. 0095].
Manassen fails to explicitly specify that wherein the sample includes a calibration cell arranged proximate to a measurement cell of the plurality of measurement cells; and calibrate the time-varying interference signals from the first photodetector and the second photodetector using the one or more calibration signals from the calibration cell to calibrate for misalignment between the first photodetector or the second photodetector.
Swillam from the same field of endeavor teaches of a calibration structure 1868 (e.g., a reference plate) may be provided on substrate table 1848 or on some other fiducial of an apparatus that substrate table 1848 may belong to (e.g., a lithographic apparatus) [pars. 0090, 0189, 0207] in order to minimized the offset between the exposed layer and the reference layer and results in the smallest overlay error.
Therefore, it would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to modify Manassen in the manner set forth in applicant’s claims 1, 14 and 27, in view of the teaching of Swillam in order to increase measurement accuracy, as per the teachings of Swillam.
Manassen when modified by Swillam, Manassen teaches of calibration or otherwise modify the overlay measurement based on known, assumed, or measured features of the sample that may also impact the time-varying interference signals such as, but not limited to, sidewall angles or other sample asymmetries [pars. 0073], and Manassen further teaches that the systems (include(s) plurality of detectors; first photodetector or the second photodetector) and/or measurements may be calibrated to increase measurement accuracy [par. 0041].
Manassen when modified by Swillam fail to explicitly specify that the calibration (Manassen, [par. 0041]) is due to misalignment between the first photodetector or the second photodetector.
Riley from the same field of endeavor teaches of calibration due to misalignment between the plurality of image sensors (plurality of photosensitive cameras 105) (figs. 1A and 1B) “first photodetector or the second photodetector” is known in the art. Riley teaches of a method is provided for correcting signal misalignment between individual channels in a multichannel imaging system, such that data in a first channel is substantially aligned with data in other channels (Riley, [pars. 0010, 0024-25, 0059] (claims 47, 48 and 55)) in order to reducing erroneous contributions to channel's measurement by sources intended for other channels and applies the spectral crosstalk corrections, to remove the channel-to-channel crosstalk from the displayed images.
Therefore, it would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to modify Manassen when modified by Swillam with the calibration due to misalignment between the first photodetector or the second photodetector in view of Manassen teachings of systems calibration [pars. 0041] and further in view of Riley teaches of performing alignment between plurality of image sensors and/or correcting signal misalignment between individual channels in a multichannel imaging system in order to increase measurement accuracy and/or improve the accuracy and/or sensitivity of the measurement [par. 0047], as per the teachings of Manassen.
For the purposes of clarity, the structure recited in claim 14 is symmetrical to the structure overlay metrology system recited in claim 1, as such, claim 14 is taught/suggested by the limitations of claim 1 as rejected above as being unpatentable over Manassen in view of Swillam and Riley. Additionally, the method claim 27 is taught/suggested by the functions shown/stated/set forth with regards to the system claims 1 and 14 as rejected above as being unpatentable over Manassen in view of Swillam and Riley.
As to claims 3-5 and 16-18, Manassen when modified by Swillam and Riley, Manassen teaches of the features of claims 3-5 5 and 16-18, as applied to claims 1 and 15 comprising the systems and/or measurements may be calibrated to increase measurement accuracy [par. 0041], and that the controller 122 may calibrate or otherwise modify the overlay measurement based on known, assumed, or measured features of the sample that may also impact the time-varying interference signals such as, but not limited to, sidewall angles or other sample asymmetries [par. 0095] and that the system is based on an overlay metrology system that is configured to scanned a sample as the sample is scanned relative to the illumination beam along a scan direction, the target including one or more cells having Moiré structures (see abstract), and a scatterometry overlay target including one or more grating-over-grating structures formed as diffraction gratings with common pitches (e.g., periods) [pars. 0033, 0035, 0038, 0040] [pars. 0067-0098, 0089-90, 0092-95], while Swillam teaches of calibration structure proximate to a measurement cell of the plurality of measurement cells, and also Swillam system is based on scanning the measurement target as well as the calibration structure [pars. 0064-66, 0166, 0170] in order to acquire, detect and accurately generate a measurement signal.
Manassen when modified by Swillam and Riley fail to teach the constructional changes in the device of claim 1, as that claimed by Applicants claims 3-5 and 16-18, such as, wherein the calibration cell includes a blank area configured to be scanned as the sample is scanned to generate one or more calibration signals (claims 3 and 16); wherein the calibration cell includes a calibration grating configured to be scanned as the sample is scanned to generate one or more calibration signals (claims 4 and 17); and wherein the calibration grating has the similar/common pitch as the first-layer grating feature and the second-layer grating feature (claims 5 and 18).
However, even though, Manassen when modified by Swillam and Riley fail to teach the constructional changes in the system of claim 1, as that claimed by Applicants claims 3-5 and 16-18, the constructional changes differences are considered obvious provision of adjustability in view of Manassen when modified by Swillam and Riley in order to meet the Manassen required for calibration in order to increase measurement accuracy, and minimized the offset between the exposed layer and the reference layer that would results in the smallest overlay error, as per teachings of Swillam.
Therefore, it would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to modify Manassen system of claim 1 when modified by Swillam, by the construction changes of claims 3-5 and 16-18 in order to meet the Manassen required for calibration in order to increase measurement accuracy, and minimized the offset between the exposed layer and the reference layer that would results in the smallest overlay error, as per teachings of Swillam in the manner set forth in applicant’s claims 3-5, since it has been held that the provision of adjustability, where needed, involves only routine skill in the art, In re Stevens, 101 USPQ 284 (CC1954).
As to claims 6-8, 19-21 and 28-30, Manassen when modified by Swillam and Riley, Manassen teaches of the features of claims 6-8, as applied to claims 2 and 14 comprising a structure that use in overlay metrology system that is implementing limitations such as, wherein the controller 122 is further configured to: receive one or more calibration signals from a calibration cell, wherein the one or more calibration signals include calibration signals associated with at least one of 0-order light or diffracted light; and calibrate the time-varying interference signals from the first photodetector and the second photodetector using the one or more calibration signals included in plurality of detectors and/or at least two photodetectors 112 positioned in a collection pupil plane 114 at locations of overlap between the 0-order diffraction and the +/−1 diffraction orders [pars. 0047-76] [pars. 0067-0098, 0089-90, 0092-95] (claims 6, 19 and 28); wherein the controller 122 is further configured to: normalize (i.e. increase measurement accuracy) the time-varying interference signals from the first photodetector and the second photodetector that is included in plurality of detectors and/or at least two photodetectors 112 positioned in a collection pupil plane 114 at locations of overlap between the 0-order diffraction and the +/−1 diffraction orders [pars. 0047-76] based on the one or more calibration signals to generate calibrated time-varying interference signals; and determine the overlay measurement based on the calibrated time-varying interference signals (see abstract) [pars. 0043, 0046, 0067-0100] [pars. 0067-0098, 0089-90, 0092-95] (claims 7, 20 and 29); and wherein the normalize (i.e. increase measurement accuracy of) the time-varying interference signals from the first photodetector and the second photodetector that is included in plurality of detectors and/or at least two photodetectors 112 positioned in a collection pupil plane 114 at locations of overlap between the 0-order diffraction and the +/−1 diffraction orders [pars. 0047-76, 0071-72] [pars. 0067-0098, 0089-90, 0092-95] based on the one or more calibration signals comprises: dividing the time-varying interference signals from the first photodetector and the second photodetector by at least one of the 0-order light or the diffracted light [pars. 0036-38, 0040, 0048, 0053, 0059-60, 0065, 0067] [pars. 0067-0098, 0089-90, 0092-95] (claims 8, 21 and 30).
As to claims 9-13 and 22-26, Manassen when modified by Swillam and Riley, Manassen teaches of the features of claims 9-13, as applied to claims 1 and 14 comprising a structure that use in overlay metrology system that is implementing limitations such as, wherein the received time-varying interference signal from the first photodetector and the second photodetector that is included in plurality of detectors and/or at least two photodetectors 112 positioned in a collection pupil plane 114 at locations of overlap between the 0-order diffraction and the +/−1 diffraction orders [pars. 0047-76, 0071-72] [pars. 0067-0098, 0089-90, 0092-95] as a function of the stage-scan direction is represented by:
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47
402
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where 1±1 is an intensity of a scatterometry signal for first-order diffraction, I0 is an intensity of a scatterometry signal for 0-order diffraction, E0 is an amplitude of a 0-order diffraction signal, E1 is an amplitude of a first-order diffraction signal, P is a target pitch, ∅ is an optical phase accumulation due to a path, and X is a position on a grating [pars. 000067-74] (claims 9 and 22); wherein an amplitude/an intensity of a scatterometry signal for first-order diffraction and offset is extracted to isolate I±1 [pars. 000067-84, 0108, 0117] (claims 10 and 23); wherein a first differential signal (D1) between the first photodetector and the second photodetector for a first measurement cell of the plurality of measurement cells is determined by:
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44
232
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where + f0 is an intended offset of the first measurement cell [pars. 000067-84, 0108, 0117] (claims 11 and 24); wherein a second differential signal (D2) between the first photodetector and the second photodetector that is included in plurality of detectors and/or at least two photodetectors 112 positioned in a collection pupil plane 114 at locations of overlap between the 0-order diffraction and the +/−1 diffraction orders [pars. 0047-76, 0071-72] [pars. 0067-0098, 0089-90, 0092-95] for a second measurement cell of the plurality of measurement cells is determined by:
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44
232
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where - f0 is an intended offset of the second measurement cell [pars. 0044, 0108, 0119-120 and 0129] (claims 12 and 25); and wherein the overlay measurement (OVL) based on the determined first differential signal for the first measurement cell and the determined second differential signal for the second measurement cell is determined by:
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74
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[pars. 0063-87] (claims 13 and 26).
Response to Arguments
Applicant’s arguments/remarks, filed on 01/07/2026, with respect to the rejection(s) of claim(s) have been considered but are moot because the arguments do not apply to the new ground(s) of rejection(s) and/or any of the combination of references being used in the current rejection.
Additional Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. The references listed in the attached form PTO-892 teach of other prior art overlay metrology system/method.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Isiaka Akanbi whose telephone number is (571) 272-8658. The examiner can normally be reached on 8:00 a.m. - 4:30 p.m.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Tarifur R. Chowdhury can be reached on (571) 272-2287. The fax phone number for the organization where this application or proceeding is assigned is 703-872-9306.
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/ISIAKA O AKANBI/Primary Examiner, Art Unit 2877