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 .
Response to Arguments
Applicant’s arguments filed June 1, 2026 have been considered and are persuasive regarding the rejection of claim 4 under 35 U.S.C. 112(b), but are unpersuasive regarding the rejections of claims 1-19 under 35 U.S.C. 103 as being unpatentable over Buxbaum in view of Liu.
Regarding the rejection of claim 4 under 35 U.S.C. 112(b), the rejection is withdrawn in view of the amendment to claim 4, which overcomes the rejection.
Regarding the rejection of claims 1-19 under 35 U.S.C. 103 as being unpatentable over Buxbaum in view of Liu, Applicant argues that “Liu does not disclose ‘multiple parallel cross-sections’ as recited in Claim 1”. In the nonfinal Office Action, Liu was not cited as teaching multiple parallel cross-sections. Rather, Liu was cited for its teaching of slicing a circuit board at angles that are non-perpendicular and non-parallel to a surface of the circuit board. The examiner cited Buxbaum, not Liu, for its teaching of slicing a substrate at multiple parallel cross-sections of the substrate at angles that are non-perpendicular and non-parallel to a surface of the substrate. One cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
Applicant also argues that Liu does not disclose “cross-sectioning to reveal internal circuit board features”. It should be noted that the claims of the present application do not recite that the cross-sectioning is performed to reveal internal circuit board features. Applicant is reminded that although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). Furthermore, the cross-sectioning of Buxbaum reveals circuit features. Furthermore, the cross-sectioning performed by Buxbaum does reveal internal circuit features such as vias and stripes. (Para. [0123], [0115]).
Applicant argues further that Liu “does not disclose 'imaging each cross-sectional slice of the circuit board to generate a respective image for each cross-sectional slice' as now recited in amended Claim 1.” Liu was not relied on in the Office Action as teaching this limitation. This limitation has been added to claim 1 by amendment by canceling original claim 5 and incorporating the subject matter of claim 5 into claim 1. In rejecting claim 5, the examiner relied on Buxbaum as teaching imaging cross-sectional slices to generate a respective image of each cross-sectional slice.
Applicant also argues that there is no motivation to combine the teachings of Buxbaum and Liu and that the examiner has not established a sufficient motivation to combine the teachings. The examiner disagrees. In the nonfinal Office Action, the examiner stated that the motivation to combine the teachings would be to allow the optical inspection technology of Buxbaum to be used to inspect circuit boards. Circuit boards and semiconductor chips both include circuit elements, such as conductive vias, stripes and other types of circuit elements, and both are inspected using optical inspection techniques. Also, teams of engineers working on a circuit board routinely collaborate with teams of engineers working on semiconductor chips that are to be mounted on the circuit board. Therefore, a person of ordinary skill in the art of PCB fabrication and optical defect detection methods would be aware of, and motivated to use, optical defect detection methods that have been successfully used with semiconductor chips.
Applicant argues further that “Buxbaum's FIB milling technique operates at an entirely different scale (nanometer-scale semiconductor features) and requires specialized equipment (FIB/SEM dual-beam systems) that is fundamentally different from the cutting tools used to cross-section circuit boards. The present specification discloses that cross-sectional slices of the circuit board 'may be made with the same tools used for traditional approaches' -i.e., mechanical cutting tools already used in circuit board quality labs.”
Again, Applicant is arguing features that are not recited in the claims. The claims do not recite any particular tool or technique for slicing the circuit board. As indicated above, limitations from the specification cannot be read into the claims. Furthermore, it is known to use ion beam milling to slice circuit boards (See article entitled “Using an Ion Milling System to Prepare Clean Cross Section”, by COXEM Co. Ltd, published Mar. 28, 2022 on AZO Materials website disclosing using ion beam milling to cross-section circuit boards and other devices. See Pages 3 and 4 duplicated below showing an image in Fig. 4 of a circuit board cross-sectioned using ion beam milling).
Excerpt from AZO Materials article:
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Applicant also argues that the examiner’s stated motivation to combine the teachings of Buxbaum and Liu “conflates Buxbaum's charged particle beam (SEM/FIB) inspection technology with optical inspection. Buxbaum's imaging is performed with electron beams, not optical systems.”
The examiner disagrees. Buxbaum explicitly refers to the SEM/FIB inspection system as a “two particle optical system. The first particle optical system can be a scanning electron microscope (SEM). The second particle optical system can be a focused ion beam optical system (FIB), using for example gallium (Ga) ions.” Therefore, Buxbaum’s imaging is performed by an optical inspection system. It should also be noted that the claims of the present application are silent as to the configuration or type of optical system used to image the circuit board.
Applicant argues further that the combined teachings of Buxbaum and Liu do not solve the problems that are solved by the present invention. Applicant argues that the present invention is capable of imaging voids and stripes as thin as 0.1 mils while slices are 2 mils thick by the angled cross-sectioning approach of the present invention. Applicant argues that the present invention enables not only detection of the presence of voids and stripes, but also their shapes and sizes. First of all, none of these features related to the type or size of circuit element are recited in the claims. Secondly, Buxbaum performs angular cross-sectioning, referred to in Buxbaum as “slant angle” cross-sectioning (Paras. [0002], [0014]) to inspect the substrate for circuit feature defects such as defects in stripes and vias (Para. [0123], [0115]). Therefore, Buxbaum and the present invention confront at least some of the same problems.
Claim Interpretation
The claims in this application are given their broadest reasonable interpretation (BRI) using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The BRI of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification. In the following, some of the terms in the claims have been given BRIs in light of the specification. These BRIs are used for purposes of searching for prior art and examining the claims, but cannot be incorporated into the claims. Should Applicant believe that different interpretations are appropriate, Applicant should point to the portions of the specification that clearly support a different interpretation.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-4 and 6-19 are rejected under 35 U.S.C. 103 as being unpatentable over U.S. Publ. Appl. No. 2022/0392793 A1 to Buxbaum et al. (hereinafter referred to as “Buxbaum”) in view of an article entitled “Fabrication of 45-Degree Integrated Mirrors for
Three-Dimensional Board-Level Optical Interconnects Realizing Efficient Light Coupling”, by Liu et al., published August 8, 2023 in 24th International Conference on Electronic Packaging Technology (ICEPT) (2023, Page(s): 1-5) (hereinafter referred to as “Liu”).
Regarding claim 1, Buxbaum discloses a method comprising:
slicing a circuit substrate (a semiconductor wafer) at multiple parallel cross-sections of the substrate (paras. [0108]-[0114], Figs. 1-3 disclose that focused ion beam milling is used to focus an ion beam 51 onto the wafer surface 55 at an angle GF relative to the surface 55 to slice the wafer into multiple parallel cross-sections 52-54; charged particle beam (CPB) imaging of the cross-sections is then performed to perform optical inspection of the circuit elements of the substrate), each slice of the substrate taken in a respective slice plane substantially non-perpendicular and substantially non-parallel to a surface of the substrate (paras. [0108]-[0114], Figs. 1-3 disclose that the angle GF is slant angle of, for example, 30°, relative to the wafer surface 55 such that the cross-sectional surfaces 52-54 are parallel to one another and are non-perpendicular and substantially non-parallel to the surface 55 of the substrate 8; Fig. 3 of Buxbaum duplicated below shows the parallel cross-sections 52-54 that are non-parallel and non-perpendicular to substrate surface 55); and
imaging each cross-sectional slice of the circuit board to generate a respective image for each cross-sectional slice (para. [0042]: “[i]n some embodiments, the disclosure comprises an algorithm and a method to generate a 3D volume image of the inspection volume. In a first step, cross-section image features can be detected in the plurality of cross-section image slices, for example by methods of object detection known in the art….”).
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Buxbaum does not explicitly disclose that the substrate 55 is a circuit board. Liu, in the same field of endeavor, discloses a system and method for slicing an optical printed circuit board (OPCB) at angles that are non-perpendicular and non-parallel to a surface of the circuit board (e.g., 45° relative to the surface of the circuit board) in order to create 45° mirrors in the circuit board (see Abstract; see also section II.B discussing using a diamond blade to slice the board to generate 45° angled surfaces that will be used for up-turned mirrors).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the present disclosure, to adapt the systems and methods of Buxbaum based on the teachings of Liu to cross-section a circuit board into parallel cross-sections that are non-perpendicular and non-parallel to a surface of the circuit board (e.g., 45°).
One of ordinary skill in the art would have been motivated to make the modification to allow the optical inspection technology of Buxbaum to be used to inspect circuit boards.
The modification could have been made by one of ordinary skill in the art before the effective filing date of the present disclosure with a reasonable expectation of success because making the modification merely involves combining prior art elements according to known methods to yield predictable results (constructing a system that uses the cross-sectioning and imaging inspection concepts and principles of Buxbaum to cross-section and inspect circuit boards).
Regarding claim 2, Buxbaum discloses that the respective slice planes (Fig. 3, planes of cross-sections 52-54) are each approximately 45 degrees relative to the surface (para. [0131] discloses that “a slant angle GF between 25° and 60° can be used”).
Regarding claim 3, Buxbaum discloses that the surface 55 of the substrate defining a reference plane has a first axis (Fig. 3, X-axis) and a second axis (Fig. 3, Y-axis) perpendicular to the first axis, each respective slice plane is tilted a substantially non-perpendicular and substantially non-parallel first angle from the first axis and rotated a substantially non-perpendicular and substantially non-parallel second angle from the second axis (para. [0110], Fig. 3 shows that each of the slice planes of the respective cross-sections 52-54 is tilted at the angle GF relative to the top surface 55; Figs. 25A-25C and para. [0211] disclose an embodiment in which the slice plane is rotated a substantially non-perpendicular and substantially non-parallel second angle from the second axis: “The second cross section surface 51.2 is again generated under angle GF, but rotated with respect to the first cross section surface 51.1 by a predetermined angle around the z-axis. In this example, the predetermined angle is 90°, but other angles are possible as well”).
Regarding claim 4, Buxbaum discloses that at least one of the first angle and of the second angle is approximately 45 degrees. Buxbaum discloses that the respective slice planes (Fig. 3, planes of cross-sections 52-54) are each approximately 45 degrees relative to the surface 55, which is in the X-Y plane shown in Fig. 3 (para. [0131] discloses that “a slant angle GF between 25° and 60° can be used”). Therefore, Buxbaum discloses that the first angle is at approximately 45 degrees.
Regarding claim 6, the BRI for the limitation “overlaying the respective images to create a three-dimensional image of the circuit board”, based on page 12, lines 8-23 of the present specification, is that it means connecting the slices through interpolation to generate the three-dimensional (3D) image.
Buxbaum discloses processing the cross-sectional image slices with an interpolation process that generates a 3D inspection volume from the cross-sectional image slices (para. [0042]: “[i]n a first step, cross-section image features can be detected in the plurality of cross-section image slices, for example by methods of object detection known in the art. The cross-section image features can be further classified in a feature classification, and the cross-section image features are classified into first cross-section image features and second cross-section image features. In a second step, a depth map can be generated for each cross-section image slice from second cross-section image features representing features of known or reference depth as described above…From the depth maps together with the plurality of first cross-section image features of the plurality of cross-section image slices, a 3D volume image of the inspection volume can be generated for example by projection and interpolation of virtual cross section images slices.”).
Regarding claim 7, the rejection of claim 6 applies mutatis mutandis to claim 7.
Regarding claim 8, the rejections of claims 1 and 5 apply mutatis mutandis to claim 8.
Regarding claim 9, the rejection of claim 2 applies mutatis mutandis to claim 9.
Regarding claim 10, the rejection of claim 3 applies mutatis mutandis to claim 10.
Regarding claim 11, the rejection of claim 4 applies mutatis mutandis to claim 11.
Regarding claim 12, the rejection of claim 6 applies mutatis mutandis to claim 12.
Regarding claim 13, the rejection of claim 7 applies mutatis mutandis to claim 13.
Regarding claim 14, the rejection of claims 1 and 5 apply mutatis mutandis to claim 14. Buxbaum discloses a non-transitory computer-readable medium storing instructions which, when executed, cause a processor to perform the operations recited in claims 1 and 5 (claims 26 and 31 of Buxbaum).
Regarding claim 15, the rejection of claim 2 applies mutatis mutandis to claim 15.
Regarding claim 16, the rejection of claim 3 applies mutatis mutandis to claim 16.
Regarding claim 17, the rejection of claim 4 applies mutatis mutandis to claim 17.
Regarding claim 18, the rejection of claim 6 applies mutatis mutandis to claim 18.
Regarding claim 19, the rejection of claim 7 applies mutatis mutandis to claim 19.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
An article entitled “Using an Ion Milling System to Prepare Clean Cross Sections”, by BOXEM Co. Ltd., published March 28, 2022 on AZO Materials website, www.azom.com/article.aspx?ArticleID=21488, discloses using ion beam milling to cross-section a circuit board (Pages 3 and 4, Fig. 4).
An article entitled “PCB News – Understanding PCB Microsectioning”, by Kavie, published November 10, 2021 on www.ipcb.com/news/8825.html, discloses cross-sectioning a PCB board at 45° or 30° angles relative to the surface of the PCB board by using a grinding process and then imaging the cross-section using a solid microscope or a high-power tomography microscope to allow “dual characteristics of straight cut and cross cut can be taken into account.” (Section 3. Oblique slice).
THIS ACTION IS MADE FINAL. 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 DANIEL J SANTOS whose telephone number is (571)272-2867. The examiner can normally be reached M-F 9-5.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Matt Bella can be reached at (571)272-7778. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/DANIEL J. SANTOS/
Examiner, Art Unit 2667
/MATTHEW C BELLA/ Supervisory Patent Examiner, Art Unit 2667
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