Detailed Action
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 .
Priority
The present application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application Serial Number 63/594,956, filed November 1, 2023
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 1/24/2024 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
The information disclosure statement (IDS) submitted on 3/18/2025 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claim(s) 1-5, 7, 8, 10, 11, 13-16, 18, 19, and 21-26 are rejected under 35 U.S.C. 103 as being unpatentable over Hill et al. (US 20230259040 A1) referred to as Hill hereinafter and further in view of Smedt et al. (US 7193715 B2) referred to as Smedt hereinafter.
Regarding claim 1, Hill teaches An overlay metrology system comprising: (“An overlay metrology system” Hill, abstract)
a controller including one or more processors configured to execute program instructions stored in a memory device, wherein the program instructions are configured to cause the one or more processors to implement a metrology recipe by: (“the scanning overlay system 100 includes a controller 168 communicatively coupled to the overlay metrology tool 102 and/or any components therein. In some embodiments, the controller 168 includes one or more processors 170. For example, the one or more processors 170 may be configured to execute a set of program instructions maintained in a memory device 172, or memory. The one or more processors 170 of a controller 168 may include any processing element known in the art.” Hill, para. [0074])
receiving one or more images of an overlay target on a sample, wherein the overlay target comprises: (“determine overlay measurements based on one or more pupil plane images from the detector.” Hill, para. [0032])
one or more Moiré structures, wherein a respective one of the one or more Moiré structures is formed from first-layer features with a first pitch on a first layer of the sample and further with second-layer features with a second pitch on a second layer of the sample, wherein the first-layer features and the second-layer features in the respective one of the one or more Moiré structures partially overlap, (“FIG. 2A is a side view of an inverted More structure pair 104, in accordance with one or more embodiments of the present disclosure. In some embodiments, an inverted More structure pair 104 includes a first More structure 202a and a second More structure 202b, each formed as a lower grating 204 on a first sample layer 206 and an upper grating 208 on a second sample layer 210. The first sample layer 206 and the second sample layer 210 may be disposed on a substrate 212 with any number of additional sample layers above, below, or between them. Further, the upper grating 208 of the first More structure 202a and the lower grating 204 of the second More structure 202b may have a first pitch P1, whereas the lower grating 204 of the first More structure 202a and the upper grating 208 of the second More structure 202b may have a second pitch P2 that is different from the first pitch P1. In FIG. 2A, the first pitch P1 is greater than the second pitch P2, though it is to be understood that this configuration is illustrative and should not be interpreted as limiting.” Hill, para. [0037]) and (“FIG. 4B is a conceptual view of a partially-overlapping pupil plane distribution of collected light 112 from a More structure 202 based on illumination at a normal incidence angle, in accordance with one or more embodiments of the present disclosure.” Hill, para. [0058])
wherein one or more overlap regions include regions of overlap between the first-layer features and the second-layer features, wherein one or more non-overlap regions include regions of non-overlap with one of the first-layer features or the second-layer features and further include one or more non-overlapping features; (“As an illustration, FIGS. 4A and 4B include exemplary pupil-plane distributions. FIG. 4A is a conceptual view of a non-overlapping pupil plane distribution of collected light 112 from a More structure 202 based on illumination at a normal incidence angle, in accordance with one or more embodiments of the present disclosure. FIG. 4B is a conceptual view of a partially-overlapping pupil plane distribution of collected light 112 from a More structure 202 based on illumination at a normal incidence angle, in accordance with one or more embodiments of the present disclosure.” Hill, para. [0058])
determining a coarse overlay measurement between the first layer and the second layer based at least in part on the one or more non-overlap regions of the one or more images; determining a fine overlay measurement between the first layer and the second layer based at least in part on the one or more overlap regions of the one or more images; and (“the method 500 includes a step 514 of determining an overlay measurement between the first sample layer and the second sample layer along the particular measurement direction based on data from the one or more detectors.” Hill, para. [0085]), (“In order for first-order diffraction from the upper grating 606 to propagate to the lower grating 610, the following condition must be met:
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where n is the lowest index of refraction of material in any layer between the upper grating 606 and the lower grating 610. This condition must be met for both pitches P and Q, since in half of the cells 602 the coarser pitch will be on top and in the other half of the cells 602 the finer pitch will be on top.” Hill, para. [0078]), and (“an overlay target is an advanced imaging metrology (AIM) target. In this configuration, each cell of the overlay target may include grating structures from different lithographic exposures in non-overlapping regions on one or more layers, where the grating structures from the different lithographic exposures have the same pitch.” Hill, para. [0028])
However, Hill does not teach generating an output overlay measurement based on the coarse overlay measurement and the fine overlay measurement.
Smedt teaches generating an output overlay measurement based on the coarse overlay measurement and the fine overlay measurement. (“The gross and fine overlay measurements are then combined in a way that is consistent with each measurement. Typically, this means that the gross overlay measurement is normalized to locate a starting point for the fine overlay measurement. The fine overlay measurement is then added or subtracted to that starting point to define a total overlay measurement.” Smedt, col. 4, lines 16-22)
Hill and Smedt are combinable because they are from the same field of endeavor, image processing in metrology.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify Hill in light of Smedt’s generating an output overlay measurement. One would have been motivated to do so because it can result in high precision and large range. (Smedt, abstract)
Regarding claim 2, Hill teaches wherein the program instructions are further configured to cause the one or more processors to implement the metrology recipe by controlling one or more process tools via one or more control signals based on the output overlay measurement. (“the controller 110 includes one or more processors 112. For example, the one or more processors 112 may be configured to execute a set of program instructions maintained in a memory 114, or memory device. The one or more processors 112 of a controller 110 may include any processing element known in the art. In this sense, the one or more processors 112 may include any microprocessor-type device configured to execute algorithms and/or instructions.” Hill, para. [0040])
Regarding claim 3, Hill teaches wherein the one or more non-overlapping features comprise: an overlap boundary between one of the one or more overlap regions and one of the one or more non-overlap regions. (“each cell of the overlay target may include grating structures from different lithographic exposures in non-overlapping regions on one or more layers, where the grating structures from the different lithographic exposures have the same pitch. In some embodiments, an overlay target is a Moiré target. In this configuration, each cell may include grating structures from different lithographic exposures in overlapping regions on two layers to form grating-over-grating structures or Moiré structures, where the grating structures from the different lithographic exposures have different pitches.” Hill, para. [0028])
Regarding claim 4, Hill teaches wherein the one or more non-overlapping features comprise: a non-overlap boundary between one of the one or more non-overlap regions and an outer boundary of the overlay target. (“each cell of the overlay target may include grating structures from different lithographic exposures in non-overlapping regions on one or more layers, where the grating structures from the different lithographic exposures have the same pitch.” Hill, para. [0028])
Regarding claim 5, Hill teaches wherein the one or more non-overlapping features comprise: an outer boundary of the overlay target. (“FIG. 1B illustrates an OTL (outside-the-lens) configuration in which the various illumination beams 108 are directed to the overlay target 104 outside of a NA (numerical aperture) of the objective lens 140. In some embodiments, the overlay metrology sub-system 102 directs the illumination beams 108 to the overlay target 104 within the NA of the objective lens 140 in a TTL (through-the-lens) configuration.” Hill, para. [0057])
Regarding claim 7, Smedt teaches wherein the fine overlay measurement has a measurement range, wherein generating the output overlay measurement based on the coarse overlay measurement and the fine overlay measurement comprises: adjusting the fine overlay measurement by an integer number of the measurement range based on the coarse overlay measurement. (“Overlay errors, detected on a wafer after exposing and developing the photoresist, can be corrected by removing the photoresist, repeating exposure on a corrected stepper-scanner, and repeating the development of the photoresist. If the measured error is acceptable but measurable, parameters of the lithography process could be adjusted based on the overlay metrology to avoid excursions for subsequent wafers.” Smedt, col. 1, lines 44-51)
Regarding claim 8, Hill teaches wherein the overlay target provides the output overlay measurement along one or more measurement directions, wherein the overlay target includes: a first set of Moiré structures, wherein the first-layer features in the first set of Moiré structures have a pitch P and the second-layer features in the first set of Moire structures have a pitch Q; and (“FIG. 6B illustrates a first Moiré structure 604a having an upper grating 606a with a first pitch (P) on a first layer 608 of the sample 106 and a lower grating 610a with a second pitch (Q) on a second layer 612 of the sample 106.” Hill, para. [0071])
a second set of Moire structures, wherein the first-layer features in the second set of Moire structures have the pitch Q and the second-layer features in the second set of Moire structures have the pitch P. (“FIG. 6B also illustrates a second Moiré structure 604b having an upper grating 606b with the second pitch (Q) on the first layer 608 of the sample 106 and a lower grating 610b with the first pitch (P) on the second layer 612 of the sample 106.” Hill, para. [0071])
Regarding claim 10, Hill teaches An overlay metrology system comprising: (“An overlay metrology system” Hill, abstract)
an imaging sub-system including one or more detectors to image a sample in response to illumination from an illumination source; and (“the system includes an illumination sub-system to illuminate the first and second More structures of one of the one or more inverted More structure pairs with common mutually coherent illumination beam distributions.” Hill, para. [0005])
a controller communicatively coupled to the imaging sub-system, the controller including one or more processors configured to execute program instructions stored in a memory device, wherein the program instructions are configured to cause the one or more processors to implement a metrology recipe by: (“the scanning overlay system 100 includes a controller 168 communicatively coupled to the overlay metrology tool 102 and/or any components therein. In some embodiments, the controller 168 includes one or more processors 170. For example, the one or more processors 170 may be configured to execute a set of program instructions maintained in a memory device 172, or memory. The one or more processors 170 of a controller 168 may include any processing element known in the art.” Hill, para. [0074])
receiving one or more images of an overlay target on the sample from the imaging sub-system, wherein the overlay target comprises: (“determine overlay measurements based on one or more pupil plane images from the detector.” Hill, para. [0032])
one or more Moiré structures, wherein a respective one of the one or more Moire structures is formed from first-layer features with a first pitch on a first layer of the sample and further from second-layer features with a second pitch on a second layer of the sample, wherein the first-layer features and the second-layer features in the respective one of the one or more Moire structures partially overlap, (“FIG. 2A is a side view of an inverted More structure pair 104, in accordance with one or more embodiments of the present disclosure. In some embodiments, an inverted More structure pair 104 includes a first More structure 202a and a second More structure 202b, each formed as a lower grating 204 on a first sample layer 206 and an upper grating 208 on a second sample layer 210. The first sample layer 206 and the second sample layer 210 may be disposed on a substrate 212 with any number of additional sample layers above, below, or between them. Further, the upper grating 208 of the first More structure 202a and the lower grating 204 of the second More structure 202b may have a first pitch P1, whereas the lower grating 204 of the first More structure 202a and the upper grating 208 of the second More structure 202b may have a second pitch P2 that is different from the first pitch P1. In FIG. 2A, the first pitch P1 is greater than the second pitch P2, though it is to be understood that this configuration is illustrative and should not be interpreted as limiting.” Hill, para. [0037]) and (“FIG. 4B is a conceptual view of a partially-overlapping pupil plane distribution of collected light 112 from a More structure 202 based on illumination at a normal incidence angle, in accordance with one or more embodiments of the present disclosure.” Hill, para. [0058])
wherein one or more overlap regions include regions of overlap between the first-layer features and the second-layer features, wherein one or more non-overlap regions include regions of non-overlap with one of the first-layer features or the second-layer features and further include one or more non-overlapping features; (“As an illustration, FIGS. 4A and 4B include exemplary pupil-plane distributions. FIG. 4A is a conceptual view of a non-overlapping pupil plane distribution of collected light 112 from a More structure 202 based on illumination at a normal incidence angle, in accordance with one or more embodiments of the present disclosure. FIG. 4B is a conceptual view of a partially-overlapping pupil plane distribution of collected light 112 from a More structure 202 based on illumination at a normal incidence angle, in accordance with one or more embodiments of the present disclosure.” Hill, para. [0058])
determining a coarse overlay measurement between the first layer and the second layer based at least in part on the one or more non-overlap regions of the one or more images; determining a fine overlay measurement between the first layer and the second layer based at least in part on the one or more overlap regions of the one or more images; and (“the method 500 includes a step 514 of determining an overlay measurement between the first sample layer and the second sample layer along the particular measurement direction based on data from the one or more detectors.” Hill, para. [0085]), (“In order for first-order diffraction from the upper grating 606 to propagate to the lower grating 610, the following condition must be met:
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where n is the lowest index of refraction of material in any layer between the upper grating 606 and the lower grating 610. This condition must be met for both pitches P and Q, since in half of the cells 602 the coarser pitch will be on top and in the other half of the cells 602 the finer pitch will be on top.” Hill, para. [0078]), and (“an overlay target is an advanced imaging metrology (AIM) target. In this configuration, each cell of the overlay target may include grating structures from different lithographic exposures in non-overlapping regions on one or more layers, where the grating structures from the different lithographic exposures have the same pitch.” Hill, para. [0028])
However, Hill does not teach generating an output overlay measurement based on the coarse overlay measurement and the fine overlay measurement.
Smedt teaches generating an output overlay measurement based on the coarse overlay measurement and the fine overlay measurement. (“The gross and fine overlay measurements are then combined in a way that is consistent with each measurement. Typically, this means that the gross overlay measurement is normalized to locate a starting point for the fine overlay measurement. The fine overlay measurement is then added or subtracted to that starting point to define a total overlay measurement.” Smedt, col. 4, lines 16-22)
Hill and Smedt are combinable because they are from the same field of endeavor, image processing in metrology.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify Hill in light of Smedt’s generating an output overlay measurement. One would have been motivated to do so because it can result in high precision and large range. (Smedt, abstract)
Regarding claim 11, Hill teaches wherein the imaging sub-system is an optical imaging sub-system, wherein the illumination comprises light. (“the image of a particular one of the two or more grating structures is generated exclusively with a single non-zero diffraction order of light from each of the illumination beams within a particular one of the pairs of illumination beams.” Hill, para. [0006])
Regarding claim 13, Hill teaches wherein the program instructions are further configured to cause the one or more processors to implement the metrology recipe by controlling one or more process tools via one or more control signals based on the output overlay measurement. (“the controller 110 includes one or more processors 112. For example, the one or more processors 112 may be configured to execute a set of program instructions maintained in a memory 114, or memory device. The one or more processors 112 of a controller 110 may include any processing element known in the art. In this sense, the one or more processors 112 may include any microprocessor-type device configured to execute algorithms and/or instructions.” Hill, para. [0040])
Regarding claim 14, refer to the explanation of claim 3.
Regarding claim 15, refer to the explanation of claim 4.
Regarding claim 16, refer to the explanation of claim 5.
Regarding claim 18, refer to the explanation of claim 7.
Regarding claim 19, refer to the explanation of claim 8.
Regarding claim 21, refer to the explanation of claim 1.
Regarding claim 22, refer to the explanation of claim 1.
Regarding claim 23, refer to the explanation of claim 3.
Regarding claim 24, refer to the explanation of claim 4.
Regarding claim 25, refer to the explanation of claim 5.
Regarding claim 26, refer to the explanation of claim 8.
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Hill and Smedt as mentioned above and further in view of Chen (US 20230244139 A1).
Regarding claim 12, the combination of Hill and Smedt does not teach wherein the imaging sub-system is a particle-beam imaging sub-system, wherein the illumination comprises at least one of an electron beam, an ion beam, or a neutral-particle beam.
However, Chen teaches wherein the imaging sub-system is a particle-beam imaging sub-system, wherein the illumination comprises at least one of an electron beam, an ion beam, or a neutral-particle beam. (“the overlapped overlay measurement patterns of the two layout patterns are irradiated with a beam of light, e.g., a coherent beam of light. However, due to a resolution limit of the optical irradiation, an electron beam based measurement has been developed.” Chen, para. [0015])
Hill, Smedt, and Chen are combinable because they are from the same field of endeavor, image processing in overlay measurement.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify Hill and Smedt in light of Chen’s electron beam. One would have been motivated to do so because it is possible to more accurately measure an overlay error using an SEM, and to increase a speed of an SEM-based overlay measurement. (Chen, para. [0063])
Allowable Subject Matter
Claims 6, 9, 17, and 20 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to PARDIS SOHRABY whose telephone number is (571)270-0809. The examiner can normally be reached Monday - Friday 9 am till 6pm.
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/PARDIS SOHRABY/ Examiner, Art Unit 2664
/JENNIFER MEHMOOD/Supervisory Patent Examiner, Art Unit 2664