Shunpei YAMAZAKI et al.

Patent Trials and Appeals BoardNov 5, 2021

2021003559 (P.T.A.B. Nov. 5, 2021)

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. 13/166,073 06/22/2011 Shunpei YAMAZAKI 0756-9368 5125 31780 7590 11/05/2021 Robinson Intellectual Property Law Office, P.C. 3975 Fair Ridge Drive Suite 20 North Fairfax, VA 22033 EXAMINER PIZARRO CRESPO, MARCOS D ART UNIT PAPER NUMBER 2814 NOTIFICATION DATE DELIVERY MODE 11/05/2021 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): ptomail@riplo.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte SHUNPEI YAMAZAKI, MASAHIRO TAKAHASHI, TAKUYA HIROHASHI, KATSUAKI TOCHIBAYASHI, YASUTAKA NAKAZAWA, and MASATOSHI YOKOYAMA Appeal 2021-003559 Application 13/166,073 Technology Center 2800 Before JEAN R. HOMERE, JASON V. MORGAN, and SHARON FENICK, Administrative Patent Judges. HOMERE, Administrative Patent Judge. DECISION ON APPEAL I. STATEMENT OF THE CASE1 Pursuant to 35 U.S.C. § 134(a), Appellant appeals from the Examiner’s rejection of claims 1–4, 6–14, and 16–20, all of the pending claims.2 Appeal Br. 3. Claims 5, 15, and 21 have been withdrawn from 1 We refer to the Specification filed June 22, 2011 (“Spec.”); the Final Office Action, mailed Dec. 10, 2019 (“Final Act.”); the Appeal Brief, filed Apr. 6, 2020 (“Appeal Br.”); the Examiner’s Answer, mailed Mar. 25, 2021 (“Ans.”); and the Reply Brief, filed May 13, 2021 (“Reply Br.”). 2 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42(a). Appellant identifies Semiconductor Energy Laboratory Co., Ltd., as the real party-in-interest. Appeal Br. 3. This appeal relates to Appeal 2021-003559 Application 13/166,073 2 consideration. Id. We have jurisdiction under 35 U.S.C. § 6(b). An oral hearing was held in this appeal on October 21, 2021. A transcript of the oral hearing will be entered into the record in due course. We affirm. II. CLAIMED SUBJECT MATTER According to Appellant, the claimed subject matter relates to manufacturing a semiconductor device having an oxide semiconductor layer within which nitrogen concentration is limited to 2 × 1019 atoms/cm3 or less to thereby inhibit bonding of oxygen and a metal included in the layer. Spec. ¶¶ 7–9. In particular, as nitrogen is entering the oxide semiconductor layer, the nitrogen concentration is kept low to reduce impurities therein such that heat resistant metals such as tungsten, platinum, or molybdenum included in the source electrode and the drain electrode are not oxidized. Id. Figure 1B, reproduced and discussed below, is useful for understanding the claimed subject matter: Appeal 2014-009520 (decided 8/16/2016) in which we reversed the Examiner’s rejection of claims 1–20. Dec. 4. Appeal 2021-003559 Application 13/166,073 3 Figure 1B above illustrates semiconductor device 550 including gate insulating layer 502 directly interposed between first gate electrode 511 and oxide semiconductor layer 513 overlapping therewith. Semiconductor device 550 further includes source electrode 515a, drain electrode 515b, and oxide insulating layer 507, which are in contact with oxide semiconductor layer 513 having a nitrogen concentration of 2 × 1019 atoms/cm3 or lower. Id. ¶¶ 27, 29, 35, 38, 49, 85. Claims 1 and 11 are independent. Claim 1, reproduced below with disputed limitations emphasized, is illustrative: 1. A semiconductor device comprising: a gate insulating layer; a first gate electrode in contact with one surface of the gate insulating layer; an oxide semiconductor layer in contact with the other surface of the gate insulating layer and overlapping with the first gate electrode; and a source electrode, a drain electrode, and an oxide insulating layer which are in contact with the oxide semiconductor layer, wherein a nitrogen concentration of the oxide semiconductor layer is 2 × 1019 atoms/cm3 or lower, Appeal 2021-003559 Application 13/166,073 4 wherein nitrogen entering the oxide semiconductor is counted in the nitrogen concentration of the oxide semiconductor, and wherein the source electrode and the drain electrode include at least one of tungsten, platinum, and molybdenum. Appeal Br. 13 (Claims App.) (emphasis added). III. REFERENCES The Examiner relies upon the following references.3 Name Reference Date Son US 2008/0299702 A1 Dec. 4, 2008 Shieh US 2010/0012932 A1 Jan. 21, 2010 Miyairi US 2010/0102313 A1 Apr. 29, 2010 IV. REJECTIONS The Examiner rejects the claims on appeal as follows: Claims 1–4, 6, 9–14, 16, 19, and 20 stand rejected under 35 U.S.C. § 102 (b) as being anticipated by Miyairi. Final Act. 2–4. Claims 7, 8, 17, and 18 stand rejected under 35 U.S.C. § 103 as being unpatentable over the combined teachings of Miyairi, Shieh, and Son. Final Act. 4–5. V. ANALYSIS We consider Appellant’s arguments seriatim, as they are presented in the Appeal Brief, pages 5–11 and the Reply Brief, pages 1–9.4 We are unpersuaded by Appellant’s contentions. Except as otherwise indicated 3 All reference citations are to the first named inventor only. 4 We have considered in this Decision only those arguments Appellant actually raised in the Briefs. Arguments not made are waived. See 37 C.F.R. § 41.37(c)(1)(iv). Appeal 2021-003559 Application 13/166,073 5 herein below, we adopt as our own the findings and reasons set forth in the Final Action, and the Examiner’s Answer in response to Appellant’s Appeal Brief. Final Act. 2–9; Ans. 3–16.5 However, we highlight and address specific arguments and findings for emphasis as follows. 1. Anticipation Rejection Appellant argues that the Examiner erred in finding that Miyairi describes “wherein a nitrogen concentration of the oxide semiconductor layer is 2 × 1019 atoms/cm3 or lower, wherein nitrogen entering the oxide semiconductor is counted in the nitrogen concentration of the oxide semiconductor” as recited in independent claim 1. Appeal Br. 5. In particular, Appellant argues that the Examiner erroneously finds Miyairi’s silence with respect to the oxide semiconductor layer containing nitrogen (i.e., reducing nitrogen impurities in making the oxide semiconductor layer) inherently describes the disputed limitations. Id. at 6–8 (citing Miyairi ¶¶ 67, 153). According to Appellant, although Miyairi does not list nitrogen among other impurities in making the oxide semiconductor layer, it is a logical fallacy to conclude from such silence that nitrogen is necessarily and completely absent from the oxide semiconductor layer. Id. at 7. Further, Appellant argues that even though Miyairi discloses forming the oxide semiconductor layer without being exposed to air, there is no indication that 5 See ICON Health and Fitness, Inc. v. Strava, Inc., 849 F.3d 1034, 1042 (Fed. Cir. 2017) (“As an initial matter, the PTAB was authorized to incorporate the Examiner’s findings.”); see also In re Brana, 51 F.3d 1560, 1564 n.13 (Fed. Cir. 1995) (upholding the PTAB’s findings, although it “did not expressly make any independent factual determinations or legal conclusions,” because it had expressly adopted the examiner’s findings). Appeal 2021-003559 Application 13/166,073 6 other layers are similarly not exposed. Reply Br. 7 (citing Miyairi ¶¶ 153– 61). More particularly, Appellant states the following: Next, although source and drain elements may not include nitrogen as a main component, it is particularly noted that this subsequent step (while the oxide semiconductor layer is still partially exposed) fails to state it is performed without exposure to air, which can contain large quantities of nitrogen ([0162]–[0166]). Possibly more importantly, subsequent desired heat and oxygen radical treatments ([0167]–[0168] expressly taught to be on the exposed channel region of the oxide semiconductor layer 103 are preferably performed in a nitrogen atmosphere. These clearly teach the desirable presence of nitrogen in a non-zero quantity that may "enter" the oxide semiconductor during manufacture. Id. Appellant’s arguments are not persuasive of reversible Examiner error. As a preliminary matter, we note the disputed claim limitations recite “a nitrogen concentration of the oxide semiconductor layer is 2 × 1019 atoms/cm3 or lower.” The claim limitations further recite “nitrogen entering the oxide semiconductor is counted in the nitrogen concentration of the oxide semiconductor.” We note, the cited claim language must be given its broadest reasonable interpretation consistent with Appellant’s disclosure, as explained in Morris: [T]he PTO applies to the verbiage of the proposed claims the broadest reasonable meaning of the words in their ordinary usage as they would be understood by one of ordinary skill in the art, taking into account whatever enlightenment by way of definitions or otherwise that may be afforded by the written description contained in the applicant’s specification. In re Morris, 127 F.3d 1048, 1054 (Fed. Cir. 1997); see also In re Zletz, 893 F.2d 319, 321 (Fed. Cir. 1989) (stating that “claims must be interpreted as Appeal 2021-003559 Application 13/166,073 7 broadly as their terms reasonably allow.”). Our reviewing court further states, “the proper … construction is not just the broadest construction, but rather the broadest reasonable construction in light of the specification.” In re Man Mach. Interface Techs. LLC, 822 F.3d 1282, 1287 (Fed. Cir. 2016). We agree with the Examiner that, under the broadest reasonable interpretation, the recitation of the oxide semiconductor layer having a nitrogen concentration of 2 × 1019 atoms/cm3 or lower interpretation encompasses a nitrogen concentration of zero (i.e., no nitrogen in the SiO layer) in which case no nitrogen enters the SiO layer, even though the claim also recites that “nitrogen entering the oxide semiconductor is counted in the nitrogen concentration of the oxide semiconductor.” A broad but reasonable interpretation of the claim in light of the specification would encompass no nitrogen entering the oxide semiconductor to be counted in the nitrogen concentration of the oxide semiconductor. As depicted in Figure 1A below, Miyairi forming an oxide semiconductor layer by using Ga2O3, ZnO, In2O3 alloys interposed between two gate electrodes selected from heat resistant metals such as aluminum, tungsten, copper, titanium, or molybdenum. Miyairi ¶¶ 65, 67, 76. 430 101 170 Appeal 2021-003559 Application 13/166,073 8 Fig. 1A depicts manufacturing a semiconductor device including oxide semiconductor layer 405 interposed between gate electrodes 401, 470. Further, Miyairi discloses that the silicon oxide film is made to a thickness of 100nm by a sputtering method and the gate insulating layer formed over the gate electrode has a thickness of 50nm to 100nm and it is formed using insulating films such as silicon oxide, silicon oxynitride, or silicon nitride to prevent impurity from the glass substrate from diffusing into and entering the oxide semiconductor. Id. ¶¶ 151. Likewise, Miyairi discloses that the formation of the oxide semiconductor film is based on non-crystal films without being exposed to air after plasma treatment. Id. ¶ 153. We agree with the Examiner that Miyairi’s disclosure of forming the oxide semiconductor layer in an air tight environment with specific alloys that do not include nitrogen describes an oxide semiconductor layer with no nitrogen concentration within which nitrogen is not entering. Ans. 6–11. While Appellant strenuously alleges that the Miyairi’s oxide semiconductor is not formed in a pure working environment and may be exposed to air or other impurities, we find no evidence on this record to support such conclusory argument. As noted in our claim construction above the claim does not require that nitrogen enter the oxide semiconductor layer. Rather, because the recitation of a nitrogen concentration between is 2 × 1019 atoms/cm3 or lower encompasses a concentration in which case no nitrogen enters the layer, we agree with the Examiner that on the record before us Miyairi’s cited disclosure describes the disputed limitations. Id. Regarding the rejections of claims 2–4, 6, 9–14, 16, 19, and 20, Appellant has not presented separate patentability arguments or has Appeal 2021-003559 Application 13/166,073 9 reiterated substantially the same arguments as those previously discussed for the patentability of claim 1. As such, claims 1–4, 6, 9–14, 16, 19, and 20 fall therewith. See 37 C.F.R. § 41.37(c)(1)(iv). 2. Obviousness Rejection Appellant argues that because neither Shieh nor Son cures the alleged deficiencies previously discussed regarding Miyairi, the proposed combination of Miyairi with the cited references does not render claims 7, 8, 17, and 18. Appeal Br. 11. As noted in our discussion of claim 1 above, we do not find such deficiencies in Miyairi for those references to cure. Accordingly, we sustain the Examiner’s rejection of claims 7, 8, 17 and 18 as being obvious over the combination of Miyairi, Shieh, and Son. VI. CONCLUSION We affirm the Examiner’s rejections of claims 1–4, 6–14, and 16–20. VII. DECISION SUMMARY In summary: Claims Rejected 35 U.S.C. § References Affirmed Reversed 1–4, 6, 9–14, 16, 19, 20 102 Miyairi 1–4, 6, 9–14, 16, 19, 20 7, 8, 17, 18 103 Miyairi, Shieh, Son 7, 8, 17, 18 Overall Outcome 1–4, 6–14, 16–20 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). See 37 C.F.R. § 1.136(a)(1)(iv). AFFIRMED