Ex Parte Visokay et alDownload PDFPatent Trial and Appeal BoardSep 9, 201611549375 (P.T.A.B. Sep. 9, 2016) Copy Citation UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE 111549,375 10/13/2006 23494 7590 09/13/2016 TEXAS INSTRUMENTS IN CORPORA TED P 0 BOX 655474, MIS 3999 DALLAS, TX 75265 FIRST NAMED INVENTOR Mark R. Visokay 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 ATTORNEY DOCKET NO. CONFIRMATION NO. TI-35227.2 6873 EXAMINER HAN, JONATHAN ART UNIT PAPER NUMBER 2818 NOTIFICATION DATE DELIVERY MODE 09/13/2016 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): uspto@ti.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte MARK R. VISOKA Y, LUIGI COLOMBO, JAMES J. CHAMBERS, ANTONIO L.P. ROTONDARO, and HAOWEN BU 1 Appeal 2015-001314 Application 11/549,375 Technology Center 2800 Before PETER F. KRATZ, WESLEY B. DERRICK, and CHRISTOPHER C. KENNEDY, Administrative Patent Judges. DERRICK, Administrative Patent Judge. DECISION ON APPEAL This is a decision on an appeal under 35 U.S.C. § 134 from the Examiner's rejection under§ 103(a) of claims 33-43 and 67 over Wallace2 in view of Maiti. 3 We have jurisdiction pursuant to 35 U.S.C. § 6. We AFFIRM. 1 Appellants identify Texas Instruments Incorporated as the real party in interest. Appeal Br. 3. 2 Wallace et al., US 6,020,243, issued February 1, 2000. 3 Maiti et al., US 5,885,870, issued March 23, 1999. Appeal2015-001314 Application 11/549,375 Appellants' claimed invention relates to methods for treating gate dielectric materials including one or more non-oxidizing anneals to densify the material, one or more oxidizing anneals to mitigate material defects, and a nitridation process to introduce nitrogen into the gate dielectric. Spec. Abstract. The independent claims-reproduced below-are illustrative: 33. A method for treating a deposited high-k gate dielectric layer during fabrication of a semiconductor device, the method compnsmg: performing a first anneal of a deposited high-k dielectric layer in a non-oxidizing ambient prior to forming a gate electrode to form a densified high-k dielectric layer; performing a second anneal of the densified high-k dielectric in an oxidizing ambient prior to forming a gate electrode; and thereafter, nitriding the densified high-k gate dielectric layer prior to forming a gate electrode to form a nitrided high-k dielectric layer. 67. A method of treating a high-k gate dielectric layer, the method comprising: performing one or more pre-nitridation anneal processes of a deposited high-k gate dielectric prior to forming a gate electrode to form a densified high-k dielectric layer; performing a nitridation process on the densified high-k dielectric layer_after the pre-nitridation anneal processes to form a nitrided high-k dielectric layer; and performing one or more post-nitridation anneal processes of a nitrided_high-k gate dielectric after the nitridation process and prior to forming a gate electrode. Appeal Br. (Claims Appendix) 9-10. 2 Appeal2015-001314 Application 11/549,375 DISCUSSION4 Upon consideration of the evidence and opposing contentions of the Appellants and the Examiner, we are unpersuaded of harmful error in the Examiner's decision rejecting the claims as unpatentable. To prevail in an appeal to this Board, Appellant must adequately explain or identify reversible error in the Examiner's rejection. See 37 C.F.R. § 41.37(c)(l)(iv) (2012); see also In re Jung, 637 F.3d 1356, 13 65---66 (Fed. Cir. 2011) (explaining that even if the Examiner had failed to make a prima facie case, it has long been the Board's practice to require an Appellant to identify the alleged error in the examiner's rejection); In re Chapman, 595 F.3d 1330, 1338 (Fed. Cir. 2010) ("[T]he burden of showing that the error is harmful normally falls upon the party attacking the agency's determination." (quoting Shinseki v. Sanders, 556 U.S. 396, 409 (2009))). The Examiner relies on Wallace for its disclosure of a method for treating a deposited high-k dielectric layer during fabrication of a semiconductor device. Final Act. 2; Ans. 3. As found by the Examiner, Wallace discloses nitriding a deposited high-k gate dielectric layer, a first anneal of a deposited high-k dielectric layer in a non-oxidizing (inert or reducing) environment to densify the substrate, and a second anneal in an oxidizing environment. Ans. 3 (citing Wallace col. 7, 11. 56-58, col. 8, 11. 4- 14). In Wallace, a deposited high-k dielectric layer is nitrided and oxidized to form a silicon-oxynitride layer, which Wallace teaches can then first be annealed in a non-oxidizing environment to densify the substrate and then be annealed in an oxidizing environment (oxygen) to improve dielectric 4 We refer to the Final Office Action mailed May 9, 2013, the Appeal Brief filed January 13, 2014, and the Examiner's Answer mailed April 11, 2014. 3 Appeal2015-001314 Application 11/549,375 properties of the silicon-oxynitride layer. See, e.g., Wallace col. 7, 11. 56-58, col. 8, 11. 4-14. The Examiner relies on Maiti for its disclosure of a method of treating a dielectric layer including annealing the dielectric layer in a non-oxidizing environment and annealing in an oxidizing environment prior to nitriding the dielectric layer. Ans. 3 (citing Maiti col. 3, 11. 15-19), Ans. 7 (citing Maiti col. 3, 11. 42-64). As determined by the Examiner, the disclosed sequential treatment of a semiconductor substrate with a first oxidation ambient, a non- oxidizing ambient, and a second oxidizing ambient prior to nitridation constitutes disclosure of a method comprising a first anneal in a non- oxidizing ambient and a second anneal in an oxidizing ambient prior to nitridation. 5 The Examiner concludes that one of ordinary skill in the art at the time of invention would have found it obvious to apply the anneal order of Maiti to the high-k dielectric of Wallace thereby arriving at the method of claim 33. Ans. 3. In concluding claim 67 is unpatentable for obviousness, the Examiner relies on Wallace's disclosure of a nitridation of a high-k gate dielectric layer followed by a post-nitridation anneal process and on Maiti's disclosure of a pre-nitridation anneal process. Ans. 5-6. Appellants contend the combination of Wallace and Maiti fails to provide the method of claim 33. Appeal Br. 4-7. 5 The method comprising the recited first anneal in a non-oxidizing ambient followed by a second anneal in an oxidizing ambient is open to one or more additional anneals, including that in an oxidizing ambient preceding the relied on non-oxidizing anneal. 4 Appeal2015-001314 Application 11/549,375 On this record, however, we do not find Appellants' arguments persuasive of reversible error in the Examiner's determination that claim 33 is unpatentable for obviousness over Wallace and Maiti. Appellants argue that the combination of non-oxidizing anneals of silicon dioxide layers of Maiti with post-nitridation anneals of the high-k dielectric in Wallace does not accomplish the claimed invention. Appeal Br. 4-5. The argument is unpersuasive because the rejection is based on the suggestion from the combined teachings to use the sequential non-oxidizing anneal, oxidizing anneal, and nitridation ofMaiti to treat the high-k dielectric of Wallace, not on literal bodily incorporation of silicon dioxide layers of Maiti into the high-k dielectric of Wallace. See In re Keller, 642 F.2d 413, 425 (CCPA 1981) ("The test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference . . . . Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art."). Appellants contend Maiti provides no rationale for modifying the anneal order of Wallace and argue that the Examiner erred in relying on the advantages cited in Maiti of improved process throughput and minimized process induced defectivity because these advantages in Maiti are due to using an in-situ process rather than the anneal order. Appeal Br. 5. Having considered the record, we are unpersuaded of any harmful error because Maiti discloses the order of annealing and nitridation, as discussed above, and Appellants fail to provide any persuasive evidence that one of ordinary skill in the art would not have found Maiti' s process treating a silicon dioxide layer to form a nitrided oxide dielectric layer also 5 Appeal2015-001314 Application 11/549,375 applicable to treating a high-k dielectric layer. Rather, Appellants merely contend that "because Maiti performs its anneals on silicon dioxide (non- high-k) rather than a high-k dielectric as in Wallace, one of ordinary skill in the art would not find it obvious to apply the anneal order of Maiti to the high-k dielectric process of Wallace." Appeal Br. 5. Appellants have not, accordingly, set forth a persuasive, substantiated argument that the Examiner erred in concluding it would have been obvious to use Maiti's process to treat a high-k dielectric layer. In re Pearson, 494 F.2d 1399, 1405 (CCPA 1974) ("Attorney's argument ... cannot take the place of evidence."). Appellants' further arguments grounded on differences in the steps performed (Appeal Br. 6, contrasting Maiti col. 1, 1. 66 to col. 2, 1. 33 with Wallace col. 7, 1. 32 to col. 8, 1. 14) fail to address Maiti's disclosure of the steps in the order according to claim 33 (Ans. 7, citing Maiti col. 3, 11. 42- 64). In contrasting the specific materials formed in Maiti's process using a silicon oxide dielectric layer with those formed in Wallace's process using a high-k dielectric layer, Appellants fail to squarely address the basis of the rejection grounded on applying a process used for one dielectric layer to another, albeit, a high-k dielectric layer. As to Appellants' point that Wallace and Maiti "are not annealing to densify the same material" and do not "form[] the same layer" (Appeal Br. 7), it too is unpersuasive of harmful error because it likewise fails to address Maiti' s disclosure of the steps in the order according to claim 3 3 (Ans. 7, citing Maiti co 1. 3, 11. 4 2-64) or exp lain why those steps in that order would not be considered applicable to Wallace's high-k dielectric layer. While not necessary to sustain the Examiner's rejection, we note deficiencies in Appellants' argument as to differences in the product formed 6 Appeal2015-001314 Application 11/549,375 when the order of processing steps are changed. Appeal Br. 7. Appellants contend there are differences in the products, but do not present any persuasive evidence or argument that changing the order of process steps results in a different product when using the same substrate. Appeal Br. 7. In regard to Appellants' reliance on the Specification's disclosure of improved/modified tailoring of nitrogen content and profile in the high-k dielectric layer (Appeal Br. 7; Spec. 16, 11. 27-30), the Specification merely sets forth that "nitridation [] itself may be facilitated by densification of the high-k material through annealing ... which may improve tailoring of the nitrogen content and profile in the high-k material." (Spec. 16, 11. 27-28) (emphasis added). It follows that even if it were necessary to rely on the Examiner's alternative reasoning that the "selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results" (Ans. 3, citing In re Gibson, 39 F.2d 975 (CCPA 1930); see also In re Burhans, 154 F .2d 690 ( CCP A 1946) ), Appellants have failed to establish error that would necessitate reversal. 6 Appellants contend the relied on combination of Wallace and Maiti fails to provide the method of claim 67. Appeal Br. 7-8. In addition to relying on the arguments as to claim 33, Appellants argue that the fact densification occurs in both Wallace and Maiti is no rationale for performing the anneals of a high-k dielectric both before and after nitridation. Appeal Br. 7-8. 6 Gibson and Burhans are applicable to situations where one of ordinary skill in the art would have reasonably expected from the steps described in the applied prior art that changing the order of steps would produce substantially the same result. 7 Appeal2015-001314 Application 11/549,375 On this record, we are unpersuaded of reversible error. As discussed above, Appellants fail to provide any persuasive evidence that one of ordinary skill in the art would not have found Maiti's process treating a silicon dioxide layer to form a nitrided oxide dielectric layer also applicable to treating a high-k dielectric layer. It then follows that we discern no reversible error where it is not disputed that Maiti discloses a process including a non-oxidizing, densifying anneal prior to nitriding, nitriding, and an optional anneal following nitridation. See, e.g., Appeal Br. 6; Maiti col. 2, 11. 6-9, 26-33, 45-51. Likewise, because Maiti discloses a pre-nitridation anneal that "densities and relieves stress" (Maiti col. 2, 11. 6-9) and that a pre-nitridation anneal improves the reliability of the resulting nitride oxide dielectric layer (Ans. 7; Maiti col. 3, 11. 42-64), we discern no reversible error the Examiner's conclusion it would have been obvious at the time of the invention to have included a pre-nitridation anneal in the process of Wallace. See, e.g., In re Preda, 401 F.2d 825, 826 (CCPA 1968) ("[I]t is proper to take into account not only specific teachings of the reference but also the inferences which one skilled in the art would reasonably be expected to draw therefrom."). Critically, Appellants direct us to no evidence and/or persuasive logic indicating that the skilled artisan would not reasonably infer that a high-k dielectric would not similarly be improved by a pre-nitridation anneal. See generally Appeal Br. For the reasons above, Appellants have failed to persuade us that the Examiner erred reversibly in concluding that one of ordinary skill in the art, armed with the teachings of Wallace and Maiti, would have been led to the subject matter of claims 33 and 67. 8 Appeal2015-001314 Application 11/549,375 Accordingly, we sustain the Examiner's obviousness rejection of claims 33--43 and 67. CONCLUSION The Examiner's rejection of claims 33--43 and 67 is AFFIRMED. No time period for taking any subsequent action in connection with this appeal maybe extended under 37 C.F.R. § 1.136(a)(l). AFFIRMED 9 Copy with citationCopy as parenthetical citation