Ex Parte Dhar et alDownload PDFPatent Trial and Appeal BoardDec 27, 201613196994 (P.T.A.B. Dec. 27, 2016) 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. 13/196,994 08/03/2011 Sarit Dhar 5308-1323 4883 65106 7590 MYERS BIGEL, P.A. P.O. BOX 37428 RALEIGH, NC 27627 12/29/2016 EXAMINER NGUYEN, KHIEM D ART UNIT PAPER NUMBER 2823 NOTIFICATION DATE DELIVERY MODE 12/29/2016 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): u spto @ my ersbigel. com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte SARIT DHAR, SEI-HYUNG RYU, ANANT AGARWAL and JOHN ROBERT WILLIAMS, Appeal 2015-007573 Application 13/196,9941 Technology Center 2800 Before JEFFREY T. SMITH, MICHAEL P. COLAIANNI, and DEBRA L. DENNETT, Administrative Patent Judges. SMITH, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE This is an appeal under 35 U.S.C. § 134 from the November 19, 2014 Final rejection of claims 1, 2, 5—7, 9—15, 18—20, and 22—24. We have jurisdiction under 35 U.S.C. § 6. We AFFIRM. 1 The real party in interest is Cree, Inc. (App. Br. 1). Appeal 2015-007573 Application 13/196,994 Appellants’ invention relates to methods of forming a semiconductor structure comprising diffusing cesium ions into the insulation layer on a semiconductor layer from a cesium ion source outside the insulation layer. (Spec. 1 8). Claim 1 is illustrative of the subject matter on appeal and reproduced from the Brief below: 1. A method of forming a semiconductor structure, providing an insulation layer on a semiconductor layer; depositing a cesium ion source on the insulation layer; and diffusing cesium ions from the cesium ion source into the insulation layer, wherein diffusing cesium ions into the insulation layer comprises annealing the insulation layer, and wherein depositing the cesium ion source comprises boiling the insulation layer in a CsCl solution. The Examiner has maintained the following rejections: Claims 1, 2, 5, 9—12, 14, 15, 18, 22, and 23 under 35 U.S.C. § 103(a) as unpatentable over the combination of Glang et al., (US 4,048,350 Sept. 13, 1977) (“Glang”) and Lou et al. (US 2010/0123140 Al May 20, 2010) (“Lou”). Claims 6, 7, 19, and 20 under 35 U.S.C. § 103(a) as unpatentable over the combination of Glang and Lou in view of Das et al. (US 7,022,378 B2 Apr. 4, 2006) (“Das”). Claims 13 and 24 under 35 U.S.C. § 103(a) as unpatentable over the combination of Glang and Lou in view of Wu et al. (US 5,986,305, Nov. 16, 1999) (“Wu”). OPINION 2 Appeal 2015-007573 Application 13/196,994 Appellants present arguments specifically directed to the independent claims 1 and 14. (App. Br. 3—10). Therefore, the dependent claims will stand or fall with their parent independent claims.2 We sustain the Examiner’s rejection for the reasons expressed in the Final Action, the Answer, and below. We refer to the Examiner’s Final Action for a complete statement of the rejection. (Final Act. 2—14). In rejecting the independent claims, the Examiner found Glang discloses a method for forming a semiconductor structure comprising providing an insulation layer 22 on a semiconductor layer 14, depositing a cesium ion source on the insulation layer and diffusing cesium ions from the cesium ion source into the insulation 22 by annealing the insulation layer. (Final Act. 2—3). The Examiner found Glang did not disclose depositing the cesium ion source by boiling the insulation in CsCl solution. The Examiner found Glang discloses annealing at a temperature of 400-800° C to diffuse the cesium ions into the insulation layer 22. The Examiner found Lou discloses a method for forming a semiconductor structure comprising depositing the cesium ion source by boiling the insulation in CsCl solution. {Id.). Lou also discloses a known method of incorporating the desired additive into the oxidized SiC substrate involves placing the device in contact with a liquid comprising the desired additive, i.e., the process of Glang. (Lou 126). The Examiner concluded it would have been obvious to a person of ordinary skill in the art to utilize the known technique of boiling 2 We limit our discussion to independent claim 1 as representative of the subject matter on appeal. 3 Appeal 2015-007573 Application 13/196,994 the insulation in CsCl solution to deposit Glang’s cesium ion source. {Id. at 4). Appellants argue boiling in CsCl as described by Lou is not suitable for providing cesium ions to Glang. (App. Br. 6—7). Appellants specifically states Glang describes forming a layer of cesium chloride on a silicon dioxide surface by immersing the wafer in aqueous cesium chloride solution at room temperature and then annealing to drive cesium ions toward the silicon-silicon dioxide interface, while Lou describes boiling in CsCl to impregnate with cesium, and then growing silicon dioxide in the presence of cesium. Glang anneals to drive the cesium ions down into the existing silicon dioxide whereas Lou boils in CsCl to impregnate with cesium and then grows the silicon dioxide in the presence of cesium on top of the existing structure. Lou also teaches that post-growth annealing may be used to “reduce the concentration of, or eliminate, any additive present in the oxide layer.” (Lou, 10031.) Hence, it would not have been predictable that depositing cesium on an existing silicon dioxide layer by boiling in CsCl as taught by Lou would be a suitable method for providing cesium ions that are to be incorporated into the existing silicon dioxide layer by annealing as in Glang. {Id. at 7). Appellants’ arguments lack persuasive merit. The Examiner concluded that it would have been obvious to utilize the known technique of boiling a silicon dioxide layer in CsCl, as taught by Lou, to deposit Glang’s cesium ion source with predictable results. See KSR Int 7 Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007) (the predictable use of known prior art elements performing the same functions they have been known to perform is normally obvious; the combination of familiar elements is likely to be 4 Appeal 2015-007573 Application 13/196,994 obvious when it does no more than yield predictable results). For the reasons fully detailed by the Examiner, (Ans. 16—17) the proposed combination of Glang and Lou is not undermined by lack of predictability. Glang’s discussion of techniques to prevent the gaseous escape of cesium during annealing does not detract from Lou’s disclosure of techniques for depositing cesium. A person of ordinary skill in the art would have reasonably expected that the deposition technique disclosed by Lou would have been suitable for Glang. Accordingly, we affirm the Examiner’s decision to reject claims 1, 2, 5—7, 9—15, 18—20, and 22—24 for the reasons presented by the Examiner and given above. ORDER The Examiner’s obviousness rejections of claims 1, 2, 5—7, 9—15, 18— 20, and 22—24 are affirmed. No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a)(1). AFFIRMED 5 Copy with citationCopy as parenthetical citation