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 .
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 1, 2, 7, 8 and 18 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Goorden et al. (Goorden) (2022/0035257).
Regarding claim 1, Goorden discloses a system (Fig. 2) comprising: an imaging system configured to receive a plurality of diffraction orders (para 0069, diffraction orders 355+ and 355- focused onto camera 365 to form image); a spatial filter (422, Fig. 4(b), 4(c), para 0079-0081) configured to block one or more undesired diffraction orders of the plurality of diffraction orders and to pass one or more desired diffraction orders of the plurality of diffraction orders (para 0070), wherein the spatial filter comprises one or more obscurations having an angular dependent radius that varies azimuthally (Fig. 4(b), 4(c), para 0070, 0079-0081, shaded region 422 corresponds to the blocking region or obscurations having an angular dependent radius that varied azimuthally); and a detector configured to receive and measure an intensity of the one or more desired diffraction orders (Fig. 2, para 0022, 0069, 0084, determine asymmetry in the periodic structure based on a detected intensity of scattered radiation, diffraction orders focused by optical component 360 onto camera 365 to form image).
Regarding claim 2, Goorden discloses wherein the spatial filter comprises two or more sections (see annotated figure below), and wherein a radius of an obscuration in each section varies from a first radial distance to a second radial distance (Fig. 4(b), 4(c)).
Regarding claim 7, Goorden discloses wherein the plurality of diffraction orders are beams of a scattered radiation at a plurality of wavelengths (para 0018, 0069, 0070, 0091, different wavelengths are diffracted at different angles; λ1 and λ2 shown in Fig. 7(a)).
Regarding claim 8, Goorden discloses wherein the one or more desired diffraction orders are the +1 diffraction orders (para 0069, scattered higher diffraction orders 355+, 355− (e.g., +1 and −1 orders respectively)).
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Regarding claim 18, Goorden discloses a method, comprising: receiving a plurality of diffraction orders (para 0069, diffraction orders 355+ and 355- focused onto camera 365 to form image); blocking, using a spatial filter (422, Fig. 4(b), 4(c), para 0079-0081), one or more undesired diffraction orders of the plurality of diffraction orders and passing one or more desired diffraction orders of the plurality of diffraction orders (para 0070); and measuring an intensity of the one or more desired diffraction orders (Fig. 2, para 0022, 0069, 0084, determine asymmetry in the periodic structure based on a detected intensity of scattered radiation, diffraction orders focused by optical component 360 onto camera 365 to form image), wherein the spatial filter comprises one or more obscurations having an angular dependent radius that varies azimuthally (Fig. 4(b), 4(c), para 0070, 0079-0081, shaded region 422 corresponds to the blocking region or obscurations having an angular dependent radius that varied azimuthally).
Claim(s) 14, 15 and 17 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by McMahon (3,891,968).
Regarding claim 14, McMahon discloses a spatial filter (19, Fig. 1, “rotating spatial filter mark 19”, col. 4, lines 17-27) comprising: an aperture (opening on spatial filter 19, Fig. 1, see annotated figure below) comprising one or more obscurations having an angular dependent radius that azimuthally varies from a first radial distance to a second radial distance (Fig. 1, see annotated figure below, col. 4, line 64 – col. 5, line 19); and one or more ridges located at an inner edge of the one or more obscurations (the lineal radial edges 20, 21 can be considered ridges or discontinuities, Fig. 1, 2, col. 4, line 64 – col. 5, line 19), and wherein the aperture is configured to rotate about its center (col. 4, line 64 – col. 5, line 19, filter mask 19 is continuously rotated).
Regarding claim 15, McMahon discloses wherein the spatial filter comprises two or more sections, and wherein the angular dependent radius of an obscuration in each section varies from the first radial distance to the second radial distance (Fig. 1, 2, see annotated figure below, the filter mask 19 can be considered having a first section and a second section with the edges 20, 21 between the two sections).
Regarding claim 17, McMahon discloses wherein the one or more ridges are configured to block radiation in a first direction and pass radiation in a second direction, and wherein the first direction is orthogonal to the second direction (Fig. 1, 2, see annotated figure below).
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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) 3-5, 12-15, 19 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Goorden et al. (Goorden) (2022/0035257) in view of McMahon.
Regarding claim 3, Goorden discloses the claimed invention as discussed above. However, Goorden does not disclose wherein the spatial filter is a motorized spatial filter and the spatial filter is configured to rotate about its center for adjustment for a varying position of the one or more desired diffraction orders. McMahon discloses a spatial filter (19, Fig. 1, col. 4, lines 17-27) which is rotated, driven by motor 27, about its center (col. 4, line 64 – col. 5, line 19, filter mask 19 is continuously rotated). Therefore, it would have been obvious to one of ordinary skill in the art to provide a spatial filter which is rotatable in order to adjust the positioning of the aperture and the obscuration to ensure that the only the desired beams pass and the undesired beams are blocked since it has been held the provision of adjustability, where needed, involves only routine skill in the art.
Regarding claim 4, Goorden discloses wherein the spatial filter is further configured to block the one or more desired diffraction orders in a first lateral direction and to pass the one or more desired diffraction orders in a second lateral direction, wherein the first lateral direction is different than the second lateral direction (Fig. 4(b), see annotated figure below).
Regarding claim 5, Goorden does not disclose a motorized spatial filter. McMahon discloses a motorized rotatable spatial filter, rotatable about a first axis extending perpendicular to the plane of the filter (19, Fig. 1, 2). Therefore, it would have been obvious to one of ordinary skill in the art to provide a motorized rotatable spatial filter, rotatable about the center or the first axis which is perpendicular to the plane defined by the first lateral direction and second lateral direction (see annotated figure below) for the reasons stated above.
Regarding claim 12 Goorden discloses a radiation source (310, Fig. 2, para 0069) configured to generate a beam of radiation; an optical system (305, para 0069) configured to receive and direct the beam along an optical axis and toward a target so as to produce scattered radiation from the target. However, Goorden does not disclose wherein the spatial filter is a motorized spatial filter, and a processor configured to control a movement of the motorized spatial filter based on a type of the target. McMahon discloses a spatial filter (19, Fig. 1, col. 4, lines 17-27) which is rotated, driven by motor 27, about its center (col. 4, line 64 – col. 5, line 19, filter mask 19 is continuously rotated). Therefore, it would have been obvious to one of ordinary skill in the art to provide a motorized spatial filter which is rotatable in order to adjust the positioning of the aperture and the obscuration to ensure that the only the desired beams pass and the undesired beams are blocked since it has been held the provision of adjustability, where needed, involves only routine skill in the art. Further, it would have been obvious to one of ordinary skill in the art to provide a processor to control the movement of the motorized spatial filter based on a type of the target since how the light is scattered depends on the type of the target as well as the wavelength as taught by Goorden (para 0078-0080).
Regarding claim 13, wherein the processor is further configured to determine a property of the target based on a difference between measured intensities of a positive diffraction order and a negative diffraction order for at least one desired diffraction order of the one or more desired diffraction orders of the plurality of diffraction orders (para 0112, differences between opposing +1 and −1 diffraction orders to determine overlay).
Regarding claim 14, Goorden discloses a spatial filter (422, Fig. 4(b), 4(c), para 0079-0081) comprising: an aperture (see opening, Fig. 4(b), 4(c)) comprising one or more obscurations having an angular dependent radius that azimuthally varies from a first radial distance to a second radial distance (Fig. 4(b), 4(c), para 0070, 0079-0081, shaded region 422 corresponds to the blocking region or obscurations having an angular dependent radius that varied azimuthally); and one or more ridges located at an inner edge of the one or more obscurations (Fig. 4(b), 4(c), see annotated figure below). However, Goorden does not disclose wherein the aperture is configured to rotate about its center. McMahon discloses a spatial filter (19, Fig. 1, col. 4, lines 17-27) which is rotated about its center (col. 4, line 64 – col. 5, line 19, filter mask 19 is continuously rotated). Therefore, it would have been obvious to one of ordinary skill in the art to provide a spatial filter which is rotatable in order to adjust the positioning of the aperture and the obscuration to ensure that the only the desired beams pass and the undesired beams are blocked since it has been held the provision of adjustability, where needed, involves only routine skill in the art.
Regarding claim 15, Goorden discloses wherein the spatial filter comprises two or more sections, and wherein the angular dependent radius of an obscuration in each section varies from the first radial distance to the second radial distance (see annotated Fig. 4(b) above showing two different sections of obscuration).
Regarding claim 19, Goorden discloses wherein the plurality of diffraction orders are beams of a scattered radiation from a target at a plurality of wavelengths (Fig. 3(b), 3(c), 4(a), 4(b), 4(c) para 0018, 0091, illumination comprises multiple wavelengths, 0074, 0075, a plurality of diffraction orders, para 0078-0081, plurality of diffraction orders scattered from a target 410). However, Goorden does not disclose rotating the spatial filter based on a property of the target. McMahon discloses rotatable spatial filter as discussed above. Since depending on the target 410, the position of the different diffraction order on the pupil plane could change, it would have been obvious to one of ordinary skill in the art to rotate the spatial filter as taught by McMahon in order to pass the desired beam and block the undesired by adjusting the position of the aperture and obscurations by rotating the filter.
Regarding claim 20, Goorden discloses determining a property of the target based on a difference between measured intensities of a positive diffraction order and a negative diffraction order for at least one desired diffraction order of the one or more desired diffraction orders of the plurality of diffraction orders (para 0112, differences between opposing +1 and −1 diffraction orders to determine overlay).
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Claim(s) 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Goorden et al. (Goorden ‘257) (2022/0035257) in view of Goorden et al. (Goorden ‘248) (2021/0157248).
Regarding claim 10, Goorden ‘257 does not disclose a filter configured to block one or more wavelengths of the plurality of wavelengths, and wherein the filter is positioned before the spatial filter in an optical path of the beams of the scattered radiation at the plurality of wavelengths. Goorden ‘248 discloses in Fig. 6, a spatial filter (433, Fig. 4 and 633, Fig. 6) for passing only the desired diffraction order and blocking undesired diffraction order (para 0064, 0070) and a filter (634, Fig. 6) configured to block one or more wavelengths of the plurality of wavelengths (para 0069, 0070), and wherein the filter is positioned before the spatial filter in an optical path of the beams of the scattered radiation at the plurality of wavelengths (Fig 6). Therefore, it would have been obvious to one of ordinary skill in the art to a spatial filter and a filter combination which blocks unwanted diffraction order and unwanted wavelength as taught by Goorden ‘248 to the invention of Goorden ‘257 depending on the intended use of the filter to block a certain wavelength at specific portion of the pupil plane.
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Goorden et al. (Goorden ‘257) (2022/0035257) in view of Goorden et al. (Goorden ‘248) (2021/0157248) as applied to claim 10 above, and further in view of Moore (2015/0309225).
The further difference between the modified Goorden ‘257 and the claimed invention is a coating, wherein the coating is configured to block one or more wavelengths of the plurality of wavelengths, and wherein the coating is deposited on an inner edge of the one or more obscurations. Moore discloses in para 0067 that wavelength selective coating may form a band-pass filter for transmission of light of a particular wavelength range, while substantially or completely blocking light of another wavelength range. Therefore, it would have been obvious to one of ordinary skill in the art to provide a coating instead of the dichroic filter as taught by Moore in order to simplify the structure of the filter by providing one structure with a coating instead of two separate structures.
Claim(s) 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over McMahon in view of Goorden et al. (Goorden) (2021/0157248) and Moore (2015/0309225).
Regarding claim 16, McMahon discloses the claimed invention as discussed above; however, McMahon does not disclose wherein the aperture further comprises: a coating configured to block one or more wavelengths, wherein the coating is deposited on the inner edge of the one or more obscurations. Goorden discloses in Fig. 4 a spatial filter (433) comprising aperture (441) for passing only the desired non-zero diffraction orders and obscurations for blocking the unwanted diffraction orders (para 0063, 0064). Goorden also discloses in Fig. 5, a wavelength dependent spatial filter or dichroic filter which is transparent to a first wavelength but opaque to a second wavelength (532, 534, para 0069). In Fig. 6, Goorden discloses a spatial filter 632 which combines the spatial filter 433 of Fig. 4 and the dichroic filter of Fig. 5. The filter 632 comprises a spatial filter 633 and a dichroic filter 634 in series and coaxial with the dichroic filter 634 overlapping an inner portion of apertures (para 0070). Moore discloses in para 0067 that wavelength selective coating may form a band-pass filter for transmission of light of a particular wavelength range, while substantially or completely blocking light of another wavelength range. Therefore, it would have been obvious to one of ordinary skill in the art to provide a spatial filter which blocks unwanted diffraction order and unwanted wavelength as taught by Goorden to the invention of McMahon depending on the intended use of the filter to block a certain wavelength at specific portion of the pupil plane and to provide a coating instead of the dichroic filter as taught by Moore in order to simplify the structure of the filter by providing one structure with a coating instead of two separate structures.
Claim(s) 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Goorden et al. (Goorden ‘257) (2022/0035257) in view of McMahon as applied to claim 14 above, and further in view of Goorden et al. (Goorden ‘248) (2021/0157248) and Moore.
The further difference between the modified Goorden ‘257 and the claimed invention is a coating configured to block one or more wavelengths, wherein the coating is deposited on the inner edge of the one or more obscurations. Goorden ‘248 discloses in Fig. 4 a spatial filter (433) comprising aperture (441) for passing only the desired non-zero diffraction orders and obscurations for blocking the unwanted diffraction orders (para 0063, 0064). Goorden ‘248 also discloses in Fig. 5, a wavelength dependent spatial filter or dichroic filter which is transparent to a first wavelength but opaque to a second wavelength (532, 534, para 0069). In Fig. 6, Goorden ‘248 discloses a spatial filter 632 which combines the spatial filter 433 of Fig. 4 and the dichroic filter of Fig. 5. The filter 632 comprises a spatial filter 633 and a dichroic filter 634 in series and coaxial with the dichroic filter 634 overlapping an inner portion of apertures (para 0070). Moore discloses in para 0067 that wavelength selective coating may form a band-pass filter for transmission of light of a particular wavelength range, while substantially or completely blocking light of another wavelength range. Therefore, it would have been obvious to one of ordinary skill in the art to provide a spatial filter which blocks unwanted diffraction order and unwanted wavelength as taught by Goorden ‘248 to the invention of Goorden ‘257 depending on the intended use of the filter to block a certain wavelength at specific portion of the pupil plane and to provide a coating instead of the dichroic filter as taught by Moore in order to simplify the structure of the filter by providing one structure with a coating instead of two separate structures.
Allowable Subject Matter
Claims 6 and 9 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.
Regarding claim 6, none of the prior art of record teaches or discloses a blocker configured to block the one or more desired diffraction orders in a first lateral direction and to pass the one or more desired diffraction orders in a second lateral direction, wherein the first lateral direction is different than the second lateral direction, wherein the blocker is actuated by a motor, and wherein a movement of the blocker is rotational about its center.
Goorden et al. (Goorden ‘257) (2022/0035257) does not disclose a blocker as claimed in addition to the spatial filter in Fig. 4(b) and 4(c).
McMahon (3,891,968) also discloses only a spatial filter (19) and does not disclose an additional blocker.
Goorden et al. (Goorden ‘248) (2021/0157248) discloses a spatial filter (366) and an additional dichroic filter for wavelength (364), but does not disclose the claimed blocker.
Regarding claim 9, none of the prior art of record teaches or discloses a first axicon system configured to spatially spread a first diffraction order at a first wavelength away from a second diffraction order at a second wavelength; and a second axicon system configured to readjust a wavefront of the first diffraction order at the first wavelength, wherein the spatial filter is positioned in an optical path between the first axicon system and the second axicon system and wherein a location of the first diffraction order at the first wavelength coincides with the location of the second diffraction order at the second wavelength.
None of the cited references disclose an axicon system to spatially spread a first diffraction order at a first wavelength away from a second diffraction order at a second wavelength or to readjust a wavefront of the first diffraction order at the first wavelength.
Brotsack (2006/0050261) discloses an illumination system for microlithography comprising a zoom axicon objective 30 and a transmission filter 36, but Brotsack does not disclose a second zoom axicon system or a spatial filter as claimed.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Smilde et al. (2012/0123581) discloses spatial filter (21, Fig. 3(a)) for blocking zeroth order diffracted beam (para 0063), but does not disclose the arrangement of obscuration as claimed.
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/PETER B KIM/ Primary Examiner, Art Unit 2882 January 24, 2026