APPLIED MATERIALS, INC.Download PDFPatent Trials and Appeals BoardMay 3, 20212020003004 (P.T.A.B. May. 3, 2021) 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. 14/599,831 01/19/2015 ALAN A. RITCHIE 20784USA 3377 55649 7590 05/03/2021 Moser Taboada / Applied Materials, Inc. 1030 Broad Street Suite 203 Shrewsbury, NJ 07702 EXAMINER BAND, MICHAEL A ART UNIT PAPER NUMBER 1794 NOTIFICATION DATE DELIVERY MODE 05/03/2021 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): ataboada@mtiplaw.com docketing@mtiplaw.com llinardakis@mtiplaw.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte ALAN A. RITCHIE, ZHENBIN GE, JENN YUE WANG, and SALLY LOU Appeal 2020-003004 Application 14/599,831 Technology Center 1700 Before JEFFREY B. ROBERTSON, JAMES C. HOUSEL, and CHRISTOPHER C. KENNEDY, Administrative Patent Judges. HOUSEL, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the Examiner’s decision to reject claims 1–5 and 7–19. We have jurisdiction under 35 U.S.C. § 6(b). We REVERSE. 1 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42. Appellant identifies Applied Materials, Inc. as the real party in interest. Appeal Brief (“Appeal Br.”) filed August 16, 2019, at 3. Appeal 2020-003004 Application 14/599,831 2 CLAIMED SUBJECT MATTER The invention relates to methods of depositing a material in features of a substrate disposed in a processing chamber by sputtering a target using a plasma formed from a first gas, and etching the deposited material in the process chamber using a plasma formed by a second gas, different from the first gas, to partially reduce overhang of material in the feature. Specification (“Spec.”) filed January 19, 2015, ¶¶ 6–7.2 In some embodiments, the atomic mass of the second gas is greater than the atomic mass of the first gas. Id. ¶ 6. In addition, the first gas may have a mass ratio to the deposited material of less than or equal to 1:1, and the second gas may have an atomic mass ratio to the deposited material of greater than 1:1. Id. ¶ 7. Claim 1, reproduced below from the Claims Appendix to the Appeal Brief, is illustrative of the claimed subject matter: 1. A method for depositing a material in a feature of a substrate, comprising: depositing the material in the feature of the substrate disposed in a process chamber by sputtering a target using a plasma formed from a first gas; and etching the deposited material in the process chamber using a plasma formed from a second gas, different than the first gas, to at least partially reduce overhang of the material in the feature, wherein an atomic mass of the second gas is greater than an atomic mass of the first gas, and wherein an atomic mass ratio of the second gas to the deposited material is greater than 1:1. 2 This Decision also cites to the Final Office Action (“Final Act.”) dated October 5, 2018, the Examiner’s Answer (“Ans.”) dated January 13, 2020, and the Reply Brief (“Reply Br.”) filed March 12, 2020. Appeal 2020-003004 Application 14/599,831 3 Independent claim 9 recites a method for depositing a compound material in a feature of a substrate similar to that of claim 1, wherein the first gas may have a mass ratio to the deposited material of less than or equal to 1:1, and the second gas may have an atomic mass ratio to the deposited material of greater than 1:1. REFERENCES The Examiner relies on the following prior art: Name Reference Date Ishibashi US 6,365,009 B1 Apr. 2, 2002 Ding et al. (“Ding197”) US 6,605,197 B1 Aug. 12, 2003 Rozbicki et al. (“Rozbicki”) US 8,298,936 B1 Oct. 30, 2012 Robison et al. (“Robison”) US 2004/0188239 A1 Sept. 30, 2004 Ding et al. (“Ding151”) US 2006/0030151 A1 Feb. 9, 2006 REJECTIONS The Examiner maintains, and Appellant requests our review of, the following rejections under 35 U.S.C. § 103: 1. Claims 1–5 and 9–13 as unpatentable over Rozbicki in view of Ding151; 2. Claims 7, 8, 14, 18, and 19 as unpatentable over Rozbicki in view of Ding151, and further in view of Robison; 3. Claim 15 as unpatentable over Rozbicki in view of Ding151, and further in view of Ishibashi; and 4. Claims 16 and 17 as unpatentable over Rozbicki in view of Ding151, and further in view of Ding197. Appeal 2020-003004 Application 14/599,831 4 OPINION The Examiner has the initial burden of establishing a prima facie case of obviousness based on an inherent or explicit disclosure of the claimed subject matter under 35 U.S.C. § 103. In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992) (“[T]he examiner bears the initial burden, on review of the prior art or on any other ground, of presenting a prima facie case of unpatentability”). To establish a prima facie case of obviousness, the Examiner must show that each and every limitation of the claim is described or suggested by the prior art or would have been obvious based on the knowledge of those of ordinary skill in the art. In re Fine, 837 F.2d 1071, 1074 (Fed. Cir. 1988). The Examiner finds that Rozbicki discloses a method of depositing a metal layer into a feature of a substrate, the method comprising deposition of the metal layer by sputtering the metal in a process chamber using a plasma formed from a gas selected from inert gases (Ne, Kr, Ar, Xe), and redistribution of the metal layer to reduce overhang in the feature by resputtering with etching in the process chamber using plasma formed from another gas selected from the inert gases (Ne, Kr, Ar, Xe). Final Act. 2. The Examiner acknowledges that Rozbicki fails to suggest selecting the second gas having an atomic mass greater than an atomic mass of the first gas. Id. However, the Examiner finds that Ding151 teaches sputter depositing a material in a feature of a substrate followed by etching, wherein the deposition uses a first inert gas and the etching uses a second gas of one or more inert gases to at least partially reduce an overhang, and the deposited material is at least one of Cu, Ta, Al, or Ti. Id. at 3. The Examiner also finds that Ding151’s second gas has an atomic mass greater than an atomic mass Appeal 2020-003004 Application 14/599,831 5 of the first gas for selective etching with uniformizing, reducing overhangs, and improving sidewall uniformity and smoothness. Id. Therefore, the Examiner concludes that it would have been obvious to select first and second gases in Rozbicki’s method such that the second gas has a greater atomic mass than the first gas in order to provide selective etching with uniformizing, reduced overhangs, and improved sidewall uniformity and smoothness. Id. The Examiner determines that the combination of Rozbicki and Ding151 teaches that the metal layer is Cu etched with a second gas of at least Ar, He, and Ne, wherein Cu has an atomic mass of 63.55 and Ar, He, and Ne have a combined atomic mass of 64.128, such that the atomic mass ratio of the second gas to the deposited material is greater than 1:1. Id. at 3– 4. Appellant argues that Rozbicki does not teach or suggest use of a different gas for the deposition and etching steps, but teaches that the same gas, Ar, is typically used for both steps. Appeal Br. 6. Appellant contends that Rozbicki does not teach any importance or benefit of using any particular inert gas for either step, nor any relationship between the gases used in each step. Id. Appellant further argues that Ding151 teaches that high selectivity is desired for an etchant gas in order to reduce overhang without etching other surfaces of the substrate, and provides that the atomic mass of the second gas must be less than the atomic mass of the deposited material. Id. at 6–7. Appellant contends that the Examiner’s determination that the atomic mass of Ding151’s two or more combination of gases is 64.128 is in error because the atomic mass is based on the mass of an atom of an element, and asserts that the atomic mass of a combined gas of Ar, He, and Ne would be based on the atomic mass of Ar. Id. at 8–9. Appeal 2020-003004 Application 14/599,831 6 Appellant’s arguments are persuasive of reversible error. Although the Examiner acknowledges that Rozbicki fails to suggest selecting the second gas having an atomic mass greater than an atomic mass of the first gas, the Examiner nonetheless determines that merely selecting various inert gases of Ar, Ne, Kr, and Xe that are known to be functionally similar and usable in different steps of deposition and etching (as taught by Rozbicki . . . ) would be obvious to one of ordinary skill in the art to attain predictable results of depositing material and then etching the deposited material to reduce/reshape the overhang. Ans. 4. The Examiner does not appear to rely on Ding151’s teachings in this determination, contrary to the rejection statement. However, as Appellant contends, Rozbicki fails to teach or suggest that the first and second gases must be different or that the second gas must have an atomic mass greater than that of the first gas and the deposited material. Nor does the Examiner provide any reasoning or logical inference based on Rozbicki’s teaching for determining that an ordinary artisan would have found such selections to have been obvious. Further, as Appellant argues, Ding151 specifically teaches that the atomic mass of the second gas must be less than the atomic mass of the deposited material—opposite of what claims 1 and 9 require. Appeal Br. 6– 7; Ding151 ¶ 12. We also agree that the Examiner erred in determining that the atomic mass of Ding151’s combined He, Ne, and Ar gases equals the sum of the atomic mass of each individual gas. An atomic mass of a mixture of inert gases cannot have a value greater than the largest atomic mass of any one inert gas. We, therefore, find no support for the Examiner’s finding that Ding151’s second gas has an atomic mass greater than an atomic mass of the first gas and the deposited material. Absent such, the Examiner’s Appeal 2020-003004 Application 14/599,831 7 conclusion that the methods of claims 1 and 9 would have been obvious lacks sufficient rational underpinning. In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006) (“[R]ejections on obviousness grounds cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.”), quoted with approval in KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007). The Examiner does not rely on Robison, Ishibashi, and Ding197 to remedy the deficiencies identified above in the combination of Rozbicki and Ding151. Accordingly, we will not sustain the Examiner’s obviousness rejections of claims 1 and 9, and claims 2–5, 7, 8, and 10–19, which depend therefrom. CONCLUSION Upon consideration of the record and for the reasons set forth above and in the Appeal and Reply Briefs, the Examiner’s decision to reject claims 1–5 and 7–19 under 35 U.S.C. § 103 is reversed. Appeal 2020-003004 Application 14/599,831 8 DECISION SUMMARY In summary: Claim(s) Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 1–5, 9–13 103 Rozbicki, Ding151 1–5, 9–13 7, 8, 14, 18, 19 103 Rozbicki, Ding151, Robison 7, 8, 14, 18, 19 15 103 Rozbicki, Ding151, Ishibashi 15 16, 17 103 Rozbicki, Ding151, Ding197 16, 17 Overall Outcome 1–5, 7–19 REVERSED Copy with citationCopy as parenthetical citation