TOYO TANSO CO., LTD.Download PDFPatent Trials and Appeals BoardDec 6, 20212021001920 (P.T.A.B. Dec. 6, 2021) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 15/360,498 11/23/2016 Satoshi Torimi P161066US00 8812 38834 7590 12/06/2021 WESTERMAN, HATTORI, DANIELS & ADRIAN, LLP 8500 LEESBURG PIKE SUITE 7500 TYSONS, VA 22182 EXAMINER LI, MEIYA ART UNIT PAPER NUMBER 2811 NOTIFICATION DATE DELIVERY MODE 12/06/2021 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): patentmail@whda.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________ Ex parte SATOSHI TORIMI, MASATO SHINOHARA, YOUJI TERAMOTO, NORIHITO YABUKI, SATORU NOGAMI, and MAKOTO KITABATAKE1 ____________ Appeal 2021-001920 Application 15/360,498 Technology Center 2800 ____________ Before ADRIENE LEPIANE HANLON, CHRISTOPHER C. KENNEDY, and SHELDON M. MCGEE, Administrative Patent Judges. KENNEDY, Administrative Patent Judge. DECISION ON APPEAL This is an appeal under 35 U.S.C. § 134(a) from the Examiner’s decision rejecting claims 13–15. We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. BACKGROUND The subject matter on appeal relates to silicon carbide (SiC) wafers. E.g., Spec. ¶ 1; Claim 13. Claim 13 is reproduced below from Appendix A 1 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42. The Appellant identifies the real party in interest as TOYO TANSO CO., LTD. Appeal Br. 2. Appeal 2021-001920 Application 15/360,498 2 of the Appeal Brief: 13. A SiC (silicon carbide) wafer, comprising: a mark showing information on a first surface of a SiC substrate, said information being conveyed by a removed portion formed into a predetermined shape on the SiC substrate, wherein the mark is on C-face/(000-1) plane, and a central region of the SiC wafer having a maximum thickness of 100 μm to 50 μm, wherein at least the first surface of the SiC substrate is single crystal SiC, wherein the central region comprises a majority of the SiC wafer. REJECTIONS ON APPEAL The claims stand rejected under 35 U.S.C. § 103 as follows: 1. Claim 13 over Kondo,2 Fissel,3 and Okada4. 2. Claim 14 over Kondo, Fissel, Okada, and Yamamura5. 3. Claim 15 over Kondo, Fissel, Okada, and Reddy6. 2 US 2014/0017447 A1 (published Jan. 16, 2014). 3 A. Fissel et al., Epitaxial growth of SiC thin films on Si-stabilized α- SiC(0001) at low temperatures by solid-source molecular beam epitaxy, 154 J. Crystal Growth 72 (1995). 4 Yu Okada et al., Thinning of a two-inch silicon carbide wafer by plasma chemical vaporization machining using a slit electrode, 778 Materials Sci. Forum 750 (2014). 5 K. Yamamura et al., Plasma assisted polishing of single crystal SiC for obtaining atomically flat strain-free surface, 60 CIRP Annals — Manufacturing Technology 571 (2011). 6 Jayadeep Deva Reddy et al., Mechanical Properties of 3C-SiC Films for MEMS Applications, 1049 Mater. Res. Soc. Symp. Proc. (2008). Appeal 2021-001920 Application 15/360,498 3 ANALYSIS The Appellant argues the claims as a group. We select claim 13 as representative, and the remaining claims will stand or fall with claim 13, from which they depend. After review of the cited evidence in the appeal record and the opposing positions of the Appellant and the Examiner, we determine that the Appellant has not identified reversible error in the Examiner’s rejection of claim 13. Accordingly, we affirm the rejection for reasons set forth below, in the Final Rejection dated November 29, 2019, and in the Examiner’s Answer. The Examiner finds that Kondo discloses an SiC wafer within the scope of claim 13 except that “Kondo does not disclose the mark is on C- face/(000-1) plane, the thickness is a maximum thickness of 100 µm to 50 µm.” Final Act. 3. The Examiner finds that Fissel teaches “in related text an epitaxial layer grown on a SiC(0001) substrate,” and that Okada teaches SiC wafers with “maximum thickness of 100 µm to 50 µm.” Id. The Examiner determines that it would have been obvious “to grow an epitaxial layer on a SiC(0001) substrate, as taught by [Fissel], and include a maximum thickness of 100 µm to 50 µm, as taught by [Okada], in Kondo’s device, in order to allow easier fabrication of high-quality epitaxial surfaces, reduce cost of the device and reduce the on-resistance in vertical devices and improve the performance of the device.” Id. at 4. The Examiner also finds that “where the[] general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art.” Id. (citing In re Aller, 220 F.2d 454, 456 (CCPA 1955)). The Examiner observes that the application on Appeal 2021-001920 Application 15/360,498 4 appeal does not attribute criticality or unexpected results to the thickness range recited by claim 13. Id. The Appellant argues that a wafer within the scope of claim 13 could not be obtained using Okada’s wafer thinning method (which involves the use of plasma chemical vaporization machining (CVM)) because the wafer would crack. Appeal Br. 8. That argument is unpersuasive. The Examiner does not propose the use of Okada’s method to achieve the recited thickness; the Examiner relies on Okada only to establish that wafer thicknesses within the recited range were known desirable thicknesses for SiC wafers. See Final Act. 3–4. The Examiner relies on Fissel in proposing that such wafer thickness could be achieved by epitaxial growth. See id. The Appellant provides no persuasive reason to believe that a layer formed by epitaxial growth and marked by laser as taught by Kondo (¶ 51) would crack, particularly given that post- marking polishing steps in Kondo appear to be optional. See Kondo ¶¶ 51, 73 (“[W]hen necessary, mechanical polishing is performed . . . .” (emphasis added)). The Appellant appears to acknowledge that rationale and argues that it is “clear error to assert that the skilled artisan would find it obvious to derive the invention as claimed based on the mere disclosure of an epitaxial layer as taught by Fissel in combination with Kondo in view of Okada” for reasons “reproduced above.” Appeal Br. 8. That argument is unpersuasive because it amounts to little more than mere disagreement with the Examiner’s rationale. See SmithKline Beecham Corp. v. Apotex Corp., 439 F.3d 1312, 1320 (Fed. Cir. 2006) (“[M]ere statements of disagreement . . . as to the existence of factual disputes do not amount to a developed argument.”). The Appeal 2021-001920 Application 15/360,498 5 Examiner proposes known methods (e.g., Fissel’s) to achieve a known suitable wafer thickness (e.g., Okada’s) for SiC wafers. The use of known elements according to their established functions typically does not result in nonobvious subject matter. See KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 416–21 (2007) (“The combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results.”); see also id. at 416 (“[W]hen a patent claims a structure already known in the prior art that is altered by the mere substitution of one element for another known in the field, the combination must do more than yield a predictable result.”). The Appellant’s arguments concerning wafer cracking rely only on paragraphs 4 and 61 of the Specification for support. See Appeal Br. 6.7 Neither of those paragraphs establish that cracking occurs in the processes of the prior art relied upon by the Examiner. Paragraph 57 of the Specification states that cracking “may” occur using certain prior art methods that involve mechanical polishing, and that it is “difficult to manufacture” thin wafers using “conventional method[s].” Spec. ¶ 57. As noted above, the method of the combined prior art proposed by the Examiner does not appear to require 7 We are aware that the file history of the application on appeal includes a Declaration from Satoshi Torimi. See Declaration dated August 22, 2018 (“Decl.”). However, although the file history includes a date on which the Declaration apparently was provided to the Office, the Declaration itself is neither signed nor dated. See Decl. Moreover, the Appellant does not cite or otherwise rely on that Declaration in this appeal. Cf. MPEP § 1205.02 (“[T]he [appeal] brief should not incorporate or reference previous responses.”). We, therefore, do not consider the Torimi Declaration or the Appellant’s previous responses to office actions in deciding this appeal. See id. Appeal 2021-001920 Application 15/360,498 6 mechanical polishing. Moreover, that something “may” happen, or that achieving a thin wafer with conventional methods is “difficult,” does not indicate reversible error in the Examiner’s rejection. Finally, we observe that the Appellant does not address or otherwise contest the Examiner’s determination that, absent criticality or unexpected results, the recited wafer thickness fails to patentably distinguish the subject matter of claim 13 from the subject matter of the combined prior art. On this record, we are not persuaded of reversible error in the Examiner’s rejection of claim 13. See In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011) (“[I]t has long been the Board’s practice to require an applicant to identify the alleged error in the examiner’s rejections . . . .”). CONCLUSION In summary: Claim Rejected 35 U.S.C. § References Affirmed Reversed 13 103 Kondo, Fissel, Okada 13 14 103 Kondo, Fissel, Okada, Yamamura 14 15 103 Kondo, Fissel, Okada, Reddy 15 Overall Outcome 13–15 No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). AFFIRMED Copy with citationCopy as parenthetical citation