Ex Parte NishimuraDownload PDFPatent Trial and Appeal BoardMay 19, 201612916695 (P.T.A.B. May. 19, 2016) Copy Citation UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE 12/916,695 11/01/2010 95683 7590 05/23/2016 Ley dig, Voit & Mayer, Ltd, (Frankfurt office) Two Prudential Plaza, Suite 4900 180 North Stetson Avenue Chicago, IL 60601-6731 FIRST NAMED INVENTOR Shigeki Nishimura 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 ATTORNEY DOCKET NO. CONFIRMATION NO. 812375 1089 EXAMINER DUCLAIR, STEPHANIE P. ART UNIT PAPER NUMBER 1713 NOTIFICATION DATE DELIVERY MODE 05/23/2016 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): chgpatent@leydig.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte SHIGEKI NISHIMURA 1 Appeal2014-009518 Application 12/916,695 Technology Center 1700 Before BRADLEY R. GARRIS, N. WHITNEY WILSON, and MONTE T. SQUIRE, Administrative Patent Judges. GARRIS, Administrative Patent Judge. DECISION ON APPEAL Pursuant to 35 U.S.C. § 134(a), Appellant appeals from the Examiner's rejection under 35 U.S.C. § 103(a) of claims 1, 2, 5, 6, 9, 11, and 12 as unpatentable over Schwab (US 2004/0266191 Al, published Dec. 30, 2004) in view of Miyazaki (US 5,976,983, issued Nov. 2, 1999) and Nishimura (US 2005/0133759 Al, published Jun. 23, 2005). We have jurisdiction under 35 U.S.C. § 6(b ). We AFFIRM. 1 Siltronic AG is identified as the Real Party in Interest. App. Br. 1. Appeal2014-009518 Application 12/916,695 Appellant claims a method of processing a silicon wafer comprising the steps of cleaning a lapped wafer with alkali thereby removing 0.3 to 0.8 µm per side of the wafer and then etching the wafer with high-purity sodium hydroxide (sole independent claim 1 ). A copy of claim 1, taken from the Claims Appendix of the Appeal Brief, appears below. 1. A method of processing a silicon wafer, the method comprising ( 1) preparing a lapped semiconductor silicon wafer and sequentially carrying out steps in the following order: (2) cleaning the wafer with a surfactant and optionally cleaning the wafer with water after the cleaning with surfactant, wherein step (2) is optionally repeated at least once; (3) cleaning the wafer with alkali thereby removing 0.3 to 0.8 µm per side of the wafer and rinsing the wafer with water thereafter; and ( 4) etching the wafer with high-purity sodium hydroxide, wherein the high-impurity sodium hydroxide has impurities including an elemental content of each of Cu, Ni, Mg and Cr of l ppb or less, an elemental content of each of Pb and Fe of 5 ppb or less, an elemental content of each of Al, Ca and Zn of 10 ppb or less, and a content of chloride, sulfate, phosphate, and nitride compounds of 1 ppm or less. App. Br. 8 (Claims Appendix). Appellant does not present separate arguments specifically directed to the dependent claims under rejection (App. Br. 3---6). Therefore, the dependent claims will stand or fall with their parent independent claim 1. We sustain the rejection for the reasons expressed in the Final Action, the Answer, and below. The Examiner finds that Schwab discloses cleaning a lapped wafer, albeit not with alkali as claimed, and then etching the wafer with high-purity 2 Appeal2014-009518 Application 12/916,695 sodium hydroxide (Final Action 2-3). The Examiner additionally finds that Miyazaki discloses cleaning a lapped wafer with alkali (id. at 3) and concludes that it would have been obvious to practice Schwab's cleaning step with alkali in view of Miyazaki (id. at 4). The Examiner further concludes that it would have been obvious to optimize the amount of material removed during the alkali cleaning step to ensure removal of damaged material, thereby resulting in the removal of 0.3 to 0.8 µm per side of wafer (id.). Appellants argue "Miyazaki teaches that at least 4 µm of material should be removed during an alkali cleaning step, as opposed to the conventional 1-2 µm, in order to prevent generation of protrusions during acid-etching" (App. Br. 4) and accordingly "Miyazaki explicitly teaches away from any material removal of less than 4 µm, including the range of 0.3 to 0.8 µm recited in claim 1" (id.). Appellant's argument lacks persuasive merit. The Examiner correctly explains that iviiyazaki teaches removing at least 4 µm to prevent generation of problems (e.g., the protrusions mentioned by Appellant in the above quoted argument) during a subsequent acid etching step and that Schwab uses a sodium hydroxide, rather than an acid, etching step (i.e., step "e") subsequent to the cleaning step (i.e., step "d") (Ans. 4--5 (citing Schwab i-fi-130-31)). For these reasons, we agree with the Examiner that Miyazaki does not teach away from removing 0.3 to 0.8 µm per wafer side during the alkali cleaning step as urged by Appellant (id.). We also agree with the Examiner that it would have been obvious to remove such an amount of wafer with the goal of optimizing removal of damaged, but not undamaged, wafer material (id. at 5). 3 Appeal2014-009518 Application 12/916,695 Appellant contends that "a person of ordinary skill in the art would have no reason to make a combination [of Schwab and Miyazaki] that ignores Miyazaki' s teaching to perform a subsequent acid etching" (Reply Br. 2). Appellant's contention is not persuasive because it is not accompanied by any explanation why an artisan would consider the subsequent acid etching step of Miyazaki to be desirable or even possible in Schwab's method of etching with sodium hydroxide. Appellant also argues that "a person of ordinary skill in the art would have no reason to combine the alkaline cleaning solution to remove material from the wafer, as described in Miyazaki, with a subsequent alkaline etching step, as described in Schwab" (id. at 3). This argument was not, but could have been, raised in the Appeal Brief. For this reason and because Appellant has not shown good cause, we will not consider the newly presented argument. See 3 7 CPR § 41.41 (b )(2) (2013). The decision of the Examiner is affirmed. TIME PERIOD FOR RESPONSE No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). 4 Copy with citationCopy as parenthetical citation