AIR PRODUCTS AND CHEMICALS, INC.

Patent Trials and Appeals BoardAug 27, 2021

2020005461 (P.T.A.B. Aug. 27, 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. 14/661,652 03/18/2015 Anupama Mallikarjunan 07812ZP USA 9175 143749 7590 08/27/2021 Versum Materials US LLC 7350 Tilghman St., Suite 104 Allentown, PA 18106-9000 EXAMINER HORNING, JOEL G ART UNIT PAPER NUMBER 1712 NOTIFICATION DATE DELIVERY MODE 08/27/2021 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): MerckKGaA_PAIR@firsttofile.com VersumPatents@emdgroup.com lisa.hoffmann@emdgroup.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte ANUPAMA MALLIKARJUNAN, HARIPIN CHANDRA, MANCHAO XIAO, XINJIAN LEI, KIRK SCOTT CUTHILL, and MARK LEONARD O’NEILL Appeal 2020-005461 Application 14/661,652 Technology Center 1700 Before JEFFREY B. ROBERTSON, JULIA HEANEY, and MERRELL C. CASHION, JR., Administrative Patent Judges. ROBERTSON, Administrative Patent Judge. DECISION ON APPEAL1 1 This Decision includes citations to the following documents: Specification filed March 18, 2015 (“Spec.”); Final Office Action mailed July 31, 2019 (“Final Act.”); Appeal Brief filed January 30, 2020 (“Appeal Br.”); Examiner’s Answer mailed May 15, 2020 (“Ans.”), and Reply Brief filed July 15, 2020 (“Reply Br.”). Appeal 2020-005461 Application 14/661,652 2 STATEMENT OF THE CASE Pursuant to 35 U.S.C. § 134(a), Appellant2 appeals from the Examiner’s decision to reject pending claims 11, 13, 14, 16, 17, 19, and 22. Appeal Br. 2. We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. CLAIMED SUBJECT MATTER Appellant states the invention relates to a method for forming a silicon oxide film. Spec. ¶ 2. Claim 11, reproduced below, is illustrative of the claimed subject matter (Appeal Br., Claims Appendix, 11): 11. A method to deposit a silicon oxide film, the method comprising steps of: a. providing the substrate in a reactor; b. introducing into the reactor at least one silicon precursor comprising at least one selected from the group consisting of bis(secbutylamino)methylsilane, bis(tert- butylamino)methylsilane, and bis(cyclohexylamino)methylsilane; c. purging the reactor with a purge gas; d. introducing an oxygen-containing source into the reactor; and e. purging reactor with purge gas, f. wherein steps b through e are repeated until a desired thickness of the film is deposited, 2 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R. § 1.42(a). Appellant identifies the real party in interest as Versum Materials, Inc. Appeal Br. 1. Appeal 2020-005461 Application 14/661,652 3 wherein the method is conducted at one or more temperatures ranging from about 25 °C to about 300 °C, and wherein the deposited silicon oxide film exhibits at least one of the following characteristics: a density of about 2.1 g/cc or greater, a wet etch rate that is less than <2.5 Å/s as measured in a solution of 1:100 dilute HF acid, and a hydrogen impurity of about 5 e20 at/cc or less as measured by SIMS. REFERENCES The prior art relied upon by the Examiner is: Name Reference Date Mallikarjunan et al. (“Mallikarjunan”) US 2010/0291321 A1 Nov. 18, 2010 Manchao Xiao et al. (“Xiao”) WO 2012/167060 A2 Dec. 6, 2012 REJECTION The Examiner rejected claims 11, 13, 14, 16, 17, 19, and 22 under 35 U.S.C. § 103 as unpatentable over Xiao and Mallikarjunan. Final Act. 2– 4. OPINION Appellant does not present separate arguments with respect to the claims subject to the rejection appealed. See Appeal Br. 3–10. We select claim 11 as representative for disposition of this rejection. 37 C.F.R. § 41.37(c)(1)(iv)(2019). Appeal 2020-005461 Application 14/661,652 4 The Examiner’s Rejection The Examiner found Xiao discloses a method for forming a carbon doped silicon oxide film by atomic layer deposition as recited in claim 11, but found that even though Xiao discloses it is desirable to produce higher density films, Xiao does not exemplify the density recited in claim 11. Final Act. 2–4, citing Xiao ¶¶ 11, 21, 29, 46. The Examiner found Mallikarjunan discloses oxygen silicon carbide films where density is an important property for barrier properties, exemplifying densities of 1.8 to 2 g/cc. Id. at 3, citing Mallikarjunan ¶¶ 44, 46, 47. The Examiner determined it would have been obvious to have chosen the claimed range of 2.1 g/cc or greater as a matter of optimization because the general conditions of the claim were disclosed in the prior art, and discovering the optimum or workable ranges would have involved only routine skill. Id. Appellant’s Contentions Appellant contends that Xiao discloses a carbon-doped silicon oxide film such that one of ordinary skill in the art would have recognized that the only way to achieve higher densities would be to remove the carbon from Xiao’s films, which reduces the density. Appeal Br. 3, 6; Reply Br. 2–4. Based on this premise, Appellant argues that one of ordinary skill in the art would not have removed the carbon dopants from Xiao’s films because doing so would increase the wet etch rate, and the Examiner has not explained why one of ordinary skill in the art would have been motivated to remove carbon dopants at the expense of wet etch rate. Id. at 6–7. Appellant argues the Examiner’s position is based on hindsight because removing carbon dopant would fundamentally change the chemistry of Xiao. Appeal 2020-005461 Application 14/661,652 5 Id. at 9–10. Thus, Appellant argues the Examiner’s position that the density recited in claim 11 would have been obtained by routine optimization is not sufficiently supported. Id. at 7–8. Issue Has Appellant demonstrated reversible error in the Examiner’s position that the method recited in claim 11, where the deposited silicon oxide film exhibits a density of about 2.1 g/c or greater, would have been obvious over Xiao and Mallikarjunan? Discussion We are not persuaded by Appellant’s arguments. Initially, we, like the Examiner (Ans. 3–4), find no evidentiary support for Appellant’s argument that removing all carbon from Xiao’s film would be required in order to achieve the density recited in claim 11. See Reply Br. 2–3. Xiao discloses effective control of the carbon content in carbon-doped silicon- containing films produces films including “one or more of the following attributes: lower relative etch rates . . . higher density, compared to films deposited using the individual precursors alone.” Xiao ¶ 11. Xiao does not disclose any particular limit to the density based on the carbon content of the carbon-doped silicon-containing film. Thus, Appellant’s argument that one of ordinary skill in the art would have to remove the carbon in Xiao’s carbon-doped silicon-containing films is not supported by Xiao. Nor does Mallikarjunan support Appellant’s arguments. Mallikarjunan discloses carbon-containing silicon films that include densities of 1.8 cc/g or greater including a density range of 1.6 – 2.2 g/cc, Appeal 2020-005461 Application 14/661,652 6 which overlaps the range in claim 11. Mallikarjunan ¶¶ 33, 44, 46. Thus, Mallikarjunan itself contradicts Appellant’s arguments. In addition, even Appellant’s Specification describes silicon oxide films “without limitation” including carbon-doped silicon oxide films having a density of about 2.1 g/cc or greater. Spec. ¶¶ 12, 13, 67. Thus, Appellant’s basic premise that complete removal of carbon from the films of Xiao would be required to achieve the density in claim 11 is not persuasive. Appellant’s argument that one of ordinary skill in the art would not have removed the carbon from the films of Xiao due to the effect on the etch rate is also unpersuasive because it is based on the same flawed premise that all of the carbon in Xiao must be removed in order to achieve the density in claim 11. In addition, as pointed out by the Examiner (Ans. 5) and discussed above, Xiao does not require films that have particular etch rates. Rather, Xiao discloses films having “one or more” attributes including higher density or lower relative etch rates. Xiao ¶ 11. We are also not persuaded by Appellant’s argument that the Examiner’s routine optimization rationale is not sufficiently supported. We find that Xiao’s disclosure of a desired “higher density” (¶ 11) in combination with Mallikarjunan’s discussion of the importance of density for adequate barrier properties (¶¶ 44, 46) provides sufficient support for the Examiner’s determination that it would have been obvious for one skilled in the art to have optimized Xiao’s films to have a density within the range recited in claim 11. See also Mallikarjunan, ¶¶ 33, 58, 59 (discussing a density range within the range recited in claim 11 and that deposition parameters may be optimized to change film properties). Appeal 2020-005461 Application 14/661,652 7 Accordingly, we affirm the Examiner’s rejection of claim 11, as well as the claims dependent therefrom, as unpatentable over Xiao and Mallikarjunan. DECISION SUMMARY In summary: Claims Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 11, 13, 14, 16, 17, 19, 22 103 Xiao, Mallikarjunan 11, 13, 14, 16, 17, 19, 22 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). See 37 C.F.R. § 1.136(a)(1)(iv). AFFIRMED