Semiconductor Energy Laboratory Co., Ltd.Download PDFPatent Trials and Appeals BoardNov 9, 20202020001804 (P.T.A.B. Nov. 9, 2020) 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. 15/263,997 09/13/2016 Shunpei YAMAZAKI 0756-11191 5988 31780 7590 11/09/2020 Robinson Intellectual Property Law Office, P.C. 3975 Fair Ridge Drive Suite 20 North Fairfax, VA 22033 EXAMINER KING, SUN MI KIM ART UNIT PAPER NUMBER 2813 NOTIFICATION DATE DELIVERY MODE 11/09/2020 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, HIDEKAZU MIYAIRI, AKIHARU MIYANAGA, KENGO AKIMOTO, and KOJIRO SHIRAISHI Appeal 2020-001804 Application 15/263,997 Technology Center 2800 Before ALLEN R. MACDONALD, JEAN R. HOMERE, and JASON V. MORGAN, 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 6, 7, 10–13, 16–19, 22, 23, 26, and 27, all of the claims pending.2 Claims App. Claims 1–5, 8, 9, 14, 15, 20, 21, 24, and 25 have been canceled. Id. We have jurisdiction under 35 U.S.C. § 6(b). 1 We refer to the Specification filed Set. 13, 2016(“Spec.”); the Final Office Action, mailed Oct. 19, 2018 (“Final Act.”); the Appeal Brief, filed July 3, 2019 (“Appeal Br.”); the Examiner’s Answer, mailed Dec. 10, 2019 (“Ans.”); and the Reply Brief, filed Jan. 7, 2020 (“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. Appeal 2020-001804 Application 15/263,997 2 An oral hearing was held in this appeal on October 29, 2020. 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 a semiconductor device having buffer layer (104a, 104b) between oxide semiconductor layer (103) and a conductive copper film (105a, 105b) thereby generating a blocking effect against oxygen so as to keep the oxygen concentration in oxide semiconductor layer (103) within an optimal range by heat treatment after film formation. Spec. ¶¶ 1, 18, 39. Figure 9B, reproduced and discussed below, is useful for understanding the claimed subject matter: Figure 9B above illustrates a semiconductor device including substrate (100) having stacked thereon conductive film/gate electrode layer (101), gate insulating layer (102), oxide semiconductor film (103) containing a first region and a channel region, buffer layer (104a, 104), and conductive copper layer (105a, 105b). Spec. ¶¶ 123–27. More specifically, as Figure 9B above illustrates, the semiconductor device includes substrate (100) having stacked thereon conductive film/gate Appeal 2020-001804 Application 15/263,997 3 electrode layer (101), gate insulating layer (102), oxide semiconductor film (103) containing a first region and a channel region. Id. ¶¶ 18, 39, 23–127. On the first region of oxide semiconductor film (103) is formed first conductive film/source electrode (105a) electrically connected thereto via buffer layer (104a) interposed therebetween, the buffer layer consisting of a conductive/oxide film containing indium-gallium-zinc-oxygen-titanium. Id. ¶¶ 18, 39. On the channel region of oxide semiconductor film (103) is formed second conductive film/drain electrode (105b) electrically connected thereto via buffer layer (104(b) interposed therebetween, the buffer layer consisting of a conductive/oxide film containing indium-gallium-zinc- oxygen-titanium. Id. An impurity element imparting n-type conductivity is contained in buffer layer (104a, 104b) to preserve the oxygen concentration in the oxide semiconductor layer (103) within an optimal range. Id. Claims 6, 12, 18, 26 and 27 are independent. Claim 6, reproduced below with disputed limitations emphasized, is illustrative: 6. A semiconductor device comprising: a conductive film; an oxide semiconductor film over the conductive film, the oxide semiconductor film comprising a first region and a channel region; a first conductive film electrically connected to the oxide semiconductor film with a first film comprising indium, gallium, zinc, oxygen, and titanium interposed therebetween; a second conductive film electrically connected to the oxide semiconductor film with a second film comprising indium, gallium, zinc, oxygen, and titanium interposed therebetween; and a pixel electrode electrically connected to the second conductive film, wherein the oxide semiconductor film comprises an end portion, a groove portion, and a portion between the groove portion and the end portion, Appeal 2020-001804 Application 15/263,997 4 wherein a thickness of the portion is larger than a thickness of the groove portion and larger than a thickness of the end portion, wherein the oxide semiconductor film extends beyond a side edge of one of the first film and the second film, the extended portion of the oxide semiconductor film being the end portion, and wherein the first region of the oxide semiconductor film is interposed between the conductive film and the first conductive film in a region where the conductive film and the first conductive film intersect each other. Appeal Br. 11 (Claims App.). III. REFERENCES The Examiner relies upon the following references.3 Name Reference Date Ono US 6,762,802 B2 July 13, 2004 Yamazaki US 2005/0012097 A1 Jan. 20, 2005 Kang US 6,900,872 B2 May 31, 2005 Sano US 2006/0108636 A1 May 25, 2006 Park US 2008/0258141 A1 Oct. 23, 2008 IV. REJECTIONS The Examiner rejects the claims on appeal as follows: Claims 26 and 27 are rejected under 35 U.S.C. § 103 as being unpatentable over the combined teachings of Park and Sano. Final Act. 2–4. Claims 6, 7 and 10 are rejected under 35 U.S.C. § 103 as being unpatentable over the combined teachings of Ono, Park, Kang, and Sano. Final Act. 4–7. 3 All reference citations are to the first named inventor only. Appeal 2020-001804 Application 15/263,997 5 Claim 11 is rejected under 35 U.S.C. § 103 as being unpatentable over the combined teachings of Ono, Park, Kang, Sano, and Yamazaki. Final Act. 7. Claims 12, 13, 16–19, 22, and 23 are rejected under 35 U.S.C. § 103 as being unpatentable over the combined teachings of Ono, Park, Yamazaki Kang, and Sano. Final Act. 8–16. V. ANALYSIS We consider Appellant’s arguments seriatim, as they are presented in the Appeal Brief, pages 8–13 and the Reply Brief, pages 1–8.4 We are unpersuaded by Appellant’s contentions. Except as otherwise indicated 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. 2–17; Ans. 3–5. However, we highlight and address specific arguments and findings for emphasis as follows. Appellant argues that the Examiner erred in finding that the combination of Park and Sano teaches or suggests “a first conductive film (or first copper film) electrically connected to an oxide semiconductor film with a first film comprising indium, gallium, zinc, oxygen and titanium interposed therebetween, and a second conductive film (or second copper film) electrically connected to the oxide semiconductor film with a second film comprising indium, gallium, zinc, oxygen and titanium interposed therebetween,” as recited in independent claims 6, 12, 18, 26 and 27. Appeal Br. 8. In particular, Appellant argues that there is insufficient 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 2020-001804 Application 15/263,997 6 evidence, absent impermissible hindsight, to support the Examiner’s conclusion that titanium, as disclosed in Sano, would be recognized as suitable element for doping the first and second films in Park to increase carrier mobility. Id. at 9 (citing Park ¶ 48, Sano ¶¶ 313). According to Appellant, although Park indicates that any element can change the semiconductor layer used in forming the channel layer to a conductive material layer, Park only recites Al, B, Si, and In as specific examples, which do not particularly include titanium. Id. at 10. Therefore, Appellant submits that because Park suggests that source and drain regions include a predetermined conductive impurity (not any impurity) as dopant to form a conductive material layer, only the exemplified impurity is predictably known to change the semiconductor layer into a conductive layer. Id. Accordingly, Appellant submits that Sano’s disclosure of adding titanium as an impurity to an amorphous oxide semiconductor thin film is intended to describe an amorphous oxide that is applicable to the channel layer of transistor or to form the semiconductor thin film; and there is insufficient evidence that titanium would predictably increase conductivity in the source and drain regions of Park’s semiconductor this film. Id. (citing Sano ¶¶ 313, 314). Appellant argues that Sano, at best, teaches that titanium may be used as an additive to an oxide in a channel region (but not necessarily in the source and drain) of a semiconductor layer to form a semiconductor thin film. Id. at 11–12. Appellant’s arguments are not persuasive of reversible Examiner error. As a preliminary matter, we note the disputed claim limitations recite a first film comprising indium, gallium, zinc, oxygen and titanium interposed between a first conductive film (or first copper film) and an oxide Appeal 2020-001804 Application 15/263,997 7 semiconductor film electrically connected thereto. The claim limitations further recite a second film comprising indium, gallium, zinc, oxygen and titanium interposed between a second conductive film (or second copper film) and the oxide semiconductor film electrically connected thereto. Therefore, the disputed claim limitations require a first film and a second film, each containing at least indium, gallium, zing, oxygen, and titanium. Each of said films being placed between a conductive film and the semiconductor film. Because the disputed claim limitations do not require changing the semiconductor layer into a conductive layer or adding titanium to the source and drain of the semiconductor layer to enhance the conductivity thereof, this argument is not commensurate with the scope of the claim. Park discloses source (52a) and drain (52b) formed on either side of an etch stopper (48) to cover corresponding portions of channel layer/ conductive oxide semiconductor (46), all having potentially the same basic composition of indium, zinc, and oxide (IZO). Park ¶ 48. Park indicates that a predetermined conductive impurity (e.g., Al, B, Si, In) may be added to the oxide semiconductor layer to form a conductive material layer, such as channel layer (46). Id. Park further discloses that source (52a) and drain (52b) can be another conductive oxide layer to form channel layer (46) including indium tin oxide (ITO) layer, TiO layer or GaO layer. Id. The Examiner relies upon Park for its teaching of adding a conductive impurity (aka dopant) to an oxide semiconductor to thereby increase the conductivity thereof. Ans. 4 (citing Park ¶¶ 48, 112). Sano discloses that Ti can be introduced as an impurity to an amorphous oxide semiconductor thin film to enhance the conductivity Appeal 2020-001804 Application 15/263,997 8 thereof. Sano ¶¶ 103, 112, 313. Sano also discloses adding Titanium as a predetermined impurity to increase the conductivity of an oxide semiconductor film. Id. at 4 citing Sano ¶¶ 112, 313). We find that the combination of the cited teachings of Park and Sano is no more than a simple arrangement of old elements with each performing the same function it had been known to perform, yielding no more than what one would expect from such an arrangement. See KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 416 (2007). Therefore, the ordinarily skilled artisan, being “a person of ordinary creativity, not an automaton,” would have been able to fit the teachings of the cited references together like pieces of a puzzle to predictably achieve a source electrically connected to a conductive oxide semiconductor film via a first film including indium, gallium, zinc, oxygen and titanium, and a drain electrically connected to the oxide semiconductor film via a second film including indium, gallium, zinc, oxygen and titanium. Appellant has not demonstrated that the Examiner’s proffered combination would have been “uniquely challenging or difficult for one of ordinary skill in the art.” Therefore, we agree with the Examiner that the proposed modification would have been within the capabilities of the ordinarily skilled artisan. See Leapfrog Enters., Inc. v. Fisher-Price, Inc., 485 F.3d 1157, 1162 (Fed. Cir. 2007) (citing KSR, 550 U.S. at 418). Although Sano’s disclosure of doping pertains to an additive to enhance the conductivity of semiconductor thin film, the modification proposed by the Examiner is not a bodily incorporation of Sano’s system into Park’s.5 Rather, it is directed to using titanium as a dopant to enhance 5 “The test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary Appeal 2020-001804 Application 15/263,997 9 the conductivity of the oxide semiconductor layer. Ans. 4–6. Further, we do not agree with the Appellant that adding such titanium to Park’s oxide semiconductor would change the principle of operation of Park’s system. Appeal Br. 12.6 Because Appellant has not proffered any portion of Sano or Park that discourages, criticizes or otherwise discredits the insertion of such addition of titanium into the Park’s oxide semiconductor, we agree with the Examiner that adding titanium to Park’s oxide semiconductor does not teach away from the claimed subject matter.7 Id. Consequently, we are satisfied reference …. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art.” In re Keller, 642 F.2d 413, 425 (CCPA 1981). “The obviousness analysis cannot be confined by the formalistic conception of the words teaching, suggestion, and motivation, or by overemphasis on the importance of … the explicit content of issued patents.” KSR, 550 U.S. at 402. 6 The argument that the proposed combination of references would render one of the references unsuitable for its intended purpose, or would change its principle of operation, is a teaching away argument. In re Gordon, 733 F.2d 900, 902 (Fed. Cir. 1984) (The court concluded that in effect, “French teaches away from the board’s proposed modification” because “if the French apparatus were turned upside down, it would be rendered inoperable for its intended purpose”) “If references taken in combination would produce a ‘seemingly inoperative device,’ . . . such references teach away from the combination and thus cannot serve as predicates for a prima facie case of obviousness.” McGinley v. Franklin Sports, Inc., 262 F.3d 1339, 1354 (Fed. Cir. 2001) (citation omitted); see also In re ICON Health & Fitness, Inc., 496 F.3d 1374, 1382 (Fed. Cir. 2007) (“a reference teaches away from a combination when using it in that combination would produce an inoperative result,” but the obviousness analysis must account for “modifications that one skilled in the art would make to a device borrowed from the prior art”). 7 The Federal Circuit has held “‘[a] reference may be said to teach away when a person of ordinary skill, upon reading the reference, would be discouraged from following the path set out in the reference, or would be led in a direction divergent from the path that was taken by the applicant.’” In Appeal 2020-001804 Application 15/263,997 10 that, on this record, the combination of Park and Sano would have taught or at least suggested a source electrically connected to a conductive oxide semiconductor film via a first film including indium, gallium, zinc, oxygen and titanium, and a drain electrically connected to the oxide semiconductor film via a second film including indium, gallium, zinc, oxygen and titanium. Ans. 4–6. Accordingly, we are not persuaded of error in the Examiner’s rejections of claims 6, 12, 18, 26, and 27 over the combined teachings of Park and Sano. Regarding the rejections of claims 7, 10–11, 13, 16, 17, 19, 22, and 23, Appellant has not presented separate patentability arguments or has reiterated substantially the same arguments as those previously discussed for the patentability of claims 6, 12, 18, 26, and 27. As such, claims 7, 10–11, 13, 16, 17, 19, 22, and 23 fall therewith. See 37 C.F.R. § 41.37(c)(1)(iv). VI. CONCLUSION We affirm the Examiner’s rejections of claims 6, 7, 10–13, 16–19, 22, 23, 26, and 27. re Kahn, 441 F.3d 977, 990 (Fed. Cir. 2006) (quoting In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994)) Appeal 2020-001804 Application 15/263,997 11 VII. DECISION SUMMARY In summary: Claims Rejected 35 U.S.C. § References Affirmed Reversed 26, 27 103 Park, Sano 26, 27 6, 7, 10 103 Ono, Park, Kang, Sano 6, 7, 10 11 103 Ono, Park, Kang, Sano, Yamazaki 11 12, 13, 16–19, 22, 23 103 Ono, Park, Yamazaki Kang, Sano 12, 13, 16–19, 22, 23 Overall Outcome 6, 7, 10–13, 16– 19, 22, 23, 26, 27 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 Copy with citationCopy as parenthetical citation