Marsh, Eugene P. et al.Download PDFPatent Trials and Appeals BoardJul 29, 202012235147 - (D) (P.T.A.B. Jul. 29, 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. 12/235,147 09/22/2008 Eugene P. Marsh MI22-3787 5513 21567 7590 07/29/2020 Wells St. John P.S. 601 W. Main Avenue Suite 600 Spokane, WA 99201 EXAMINER DEHGHAN, QUEENIE S ART UNIT PAPER NUMBER 1741 NOTIFICATION DATE DELIVERY MODE 07/29/2020 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): docketing@wellsip.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________ Ex parte EUGENE P. MARSH, TIM QUICK, STEFAN UHLENBROCK, and BRENDA KRAUS ____________ Appeal 2019-005267 Application 12/235,147 Technology Center 1700 ____________ Before JAMES C. HOUSEL, MICHELLE N. ANKENBRAND, and JULIA HEANEY, Administrative Patent Judges. ANKENBRAND, Administrative Patent Judge. DECISION ON APPEAL Appellant1 appeals under 35 U.S.C. § 134(a) from the Examiner’s decision2 finally rejecting claims 63–70. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. 1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R. § 1.42. Appellant identifies Micron Technology, Inc. as the real party in interest. Appeal Brief, filed Mar. 23, 2018 (“Appeal Br.”) 3. 2 Final Action, mailed August 17, 2017 (“Final Act.”). Appeal 2019-005267 Application 12/235,147 2 STATEMENT OF THE CASE Background The subject matter on appeal relates to deposition systems and methods, including chemical vapor deposition (CVD) systems and methods. Specification, filed September 22, 2008 (“Spec.”) ¶ 1. The Specification explains that some reactive materials used for CVD are much more expensive than others, with precursor compounds (e.g., complex molecules, such as metallorganic compositions) being more expensive than reactants (e.g., simple molecules). Id. ¶ 5. Precursor compounds may comprise precious metals and may be several times more expensive than their constituent precious metals. Id. ¶ 6. In addition, some precursor compounds used in CVD processes will remain unreacted and subsequently be exhausted from the CVD reaction chamber. Id. ¶ 12. Thus, “[i]t would be desirable to develop systems and methods which reduce expenses associated with precursor materials.” Id. ¶ 7. To that end, the Specification discloses methods for reclaiming unreacted precursor material so the precursor material may be reintroduced into a deposition process. Id. ¶ 12. Specifically, the Specification discloses a deposition process for recycling trapped precursor material that includes, among other things, a pair of precursor traps configured to trap precursor under a first condition and to release the trapped precursor under a second condition. Id. ¶¶ 13, 17. Of the appealed claims, claim 63 is independent. Claim 63 is representative of the subject matter on appeal, and is reproduced below. Appeal 2019-005267 Application 12/235,147 3 63. A CVD method, the method comprising: flowing a mixture of materials into a reaction chamber, the mixture comprising deposition precursor (CH3)3(CH3C5H4)Pt and reactants; reacting the reactants with the (CH3)3(CH3C5H4)Pt to form a deposit, some of the (CH3)3(CH3C5H4)Pt remaining unreacted; after the reacting, exhausting the reaction chamber, the exhaust from the reaction chamber comprising remaining unreacted (CH3)3(CH3C5H4)Pt and reactants; flowing the exhaust across at least one of at least two parallel traps; trapping at least a portion of unreacted (CH3)3(CH3C5H4)Pt relative to other components of the exhaust in the one trap while maintaining the one trap at less than about 0°C; while trapping at least a portion of unreacted (CH3)3(CH3C5H4)Pt relative to other components of the exhaust in the one trap, releasing trapped precursor from the other of the two parallel traps while maintaining the other trap at greater than 25°C; and transferring the released trapped precursor directly from the other of the two parallel traps to the reaction chamber to form part of the mixture of materials. Appeal Br. 19 (Claims App’x). The References Peck et al. US 2008/0206445 A1 Aug. 28, 2008 Schmitt et al. US 6,402,806 B1 June 11, 2002 Li et al. US 6,921,710 B2 July 26, 2005 Kodas et al., The Chemistry of Metal CVD, John Wiley & Sons, p. 336 (2008). Appeal 2019-005267 Application 12/235,147 4 The Rejection The Examiner maintains the rejection of claims 63–70 under 35 U.S.C. § 103(a) as unpatentable over Peck in view of Schmitt, Li, and Kodas. Final Act. 2–6. OPINION Appellant presents arguments for claim 63. Appeal Br. 5–17. Appellant does not present separate arguments for claims 64–70. Id. at 18. Therefore, claims 64–70 stand or fall with claim 63. See 37 C.F.R. § 41.37(c)(1)(iv). The Examiner finds Peck discloses a CVD method that includes flowing a mixture of precursor material and a reactant into a reaction chamber, flowing exhaust across a precursor trap, and releasing trapped precursor to transfer it directly back into the reaction chamber. Final Act. 2. The Examiner finds Peck does not suggest at least two parallel traps and alternating between them, but finds Schmitt discloses a CVD process that uses parallel cold traps. Id. at 2–3. The Examiner concludes it would have been obvious to modify Peck in view of Schmitt to use parallel traps that would allow one trap to trap precursor while the other trap releases precursor and that this would provide a continuous and efficient deposition process. Id. at 3–4. The Examiner finds Peck discloses a platinum precursor material and Li discloses the use of methylcyclopentadienyl (trimethyl) platinum ((CH3)3(CH3C5H4)Pt) as a precursor in a CVD process. Id. at 4. The Examiner concludes it would have been obvious to modify Peck to use (CH3)3(CH3C5H4)Pt as a precursor because it allows for better coverage during deposition. Id. at 4. Appeal 2019-005267 Application 12/235,147 5 The Examiner further finds Peck discloses a low operating trap temperature, such as -50°C or -100°C. Id. at 4. The Examiner reasons that a higher temperature would have been necessary to release trapped precursor and finds that Kodas discloses higher vapor pressures for (CH3)3(CH3C5H4)Pt at above 25°C. Id. at 4–5. In view of this, the Examiner concludes it would have been obvious to use cold trap temperatures to trap unreacted precursor and to set Peck’s trap temperature above 25°C in order to release trapped (CH3)3(CH3C5H4)Pt precursor. Id. at 5. Appellant addresses the Examiner’s modification of Peck in view of Schmitt, arguing that the Examiner uses a skewed interpretation of Schmitt’s teachings because Schmitt uses a single hot trap for unreacted precursors and multiple cold traps for trapping organic breakdown products, which are not recycled back to a reaction chamber. Appeal Br. 8–12, 15, 17; Reply Brief, filed June 30, 2019 (“Reply Br.”), 3–6. Thus, Appellant argues that one of ordinary skill in the art would have reviewed Schmitt and would have used a hot trap for precursors, not a cold trap, and that one of ordinary skill in the art would not have combined Peck and Schmitt. Appeal Br. 11; Reply Br. 6–7. “The test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference.” In re Keller, 642 F.2d 413, 425 (CCPA 1981). “Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art.” Id. Appellant’s arguments are not persuasive because they fail to consider what Peck’s and Schmitt’s combined teachings would have taught or suggested to one of ordinary skill in the art. Appeal 2019-005267 Application 12/235,147 6 Peck teaches that precursors in CVD can be used at a rate as low as 10% or less and, therefore, most of the introduced organometallic compound may be exhaust gas. Peck ¶ 3. Peck also recognizes that “[o]rganometallic compounds are generally expensive” and expresses a need in the art for selectively recovering unreacted organometallic compounds from the exhaust gases of CVD processes. Id. ¶¶ 4, 6–7. Specifically, Peck discloses controlling the temperature of a variable temperature condenser to recover unreacted organometallic compounds. Id. ¶¶ 8–10. According to Peck, the organometallic compounds to be used in Peck’s invention are not particularly limited and can be a platinum compound. Id. ¶ 60. In addition, content recovered in Peck’s process may be conveyed directly back to the input of the process. Id. ¶ 70. Therefore, Peck’s disclosure supports the Examiner’s findings discussed above and in the Final Action. Schmitt discloses a process that recovers compounds from a CVD process for depositing copper layers. Schmitt, 1:11–15. Schmitt also recognizes that some precursor material does not react, which in the case of copper precursor can lead to deposition on a hot vacuum pump. Id. at 2:4–6. In view of this, Schmitt discloses using a hot trap to remove unreacted precursor from the exhaust of a CVD process and removing a metal-organic reaction byproduct via a cold trap. Id. at 2:17–28, 3:8–18, 5:66–6:6. Schmitt further teaches the use of a bypass cold trap in parallel with a primary cold trap so one cold trap can be removed and replaced while the other is in use without disrupting product flow through a processing chamber. Id. at 6:22–25, 6:36–7:13. In response to Appellant’s arguments regarding the combination of Peck and Schmitt, the Examiner explains that Schmitt was relied upon for Appeal 2019-005267 Application 12/235,147 7 the general teaching of parallel traps. Examiner’s Answer, mailed April 30, 2019 (“Ans.”), 5. Nonetheless, the Examiner also finds that Schmitt teaches the use of parallel traps for its hot trap. Id. (quoting Schmitt, 6:22–28). In other words, the Examiner explains how Schmitt not only teaches using parallel traps to recapture compounds from CVD exhaust gas (and that one trap can be used to trap material while the other does not), but also teaches using parallel traps to recapture precursor compounds from CVD exhaust gas. Schmitt’s disclosure further supports the Examiner’s rationale for modifying Peck in view of Schmitt because it teaches that parallel traps avoid disrupting product flow through the processing chamber of a CVD process. Schmitt, 6:22–28. Appellant next contends that Schmitt is directed to using a specific copper organometallic precursor and does not suggest that its process can be used for other organometallic precursors. Appeal Br. 11; Reply Br. 6, 8–9. In view of this, Appellant argues that a combination of Peck and Schmitt would have required improper picking and choosing of teachings rather than viewing each of the references as a whole. Appeal Br. 11–12. Appellant also argues that because Schmitt discloses purification before transfer of trapped materials, the combination of Peck and Schmitt would not have resulted in direct transfer of trapped material to a reaction chamber. Appeal Br. 12–13; Reply Br. 9. These arguments are also unpersuasive because they do not properly consider what the combined disclosures of Peck and Schmitt would have suggested to one of ordinary skill in the art. As noted above, Peck discloses using various organometallic precursors, including platinum compounds, and also discloses that recovered content may be conveyed directly back to Appeal 2019-005267 Application 12/235,147 8 the input of the CVD process. Peck ¶¶ 60, 70. Appellant’s argument that Schmitt does not suggest that its process can be used for other precursors appears to rely on the bodily incorporation of Schmitt’s process into Peck’s, which is not the proper basis for determining obviousness. Further, to the extent Schmitt discloses purification before transferring captured material back to a reaction chamber, Appellant’s arguments fail to explain sufficiently why the direct transfer process Peck discloses would not have been obvious when modifying Peck in view of Schmitt. Appellant further asserts that Peck discloses “a broad swath of organometallics,” Peck does not mention what metal the organometallics contain or what the organic portion is, and Peck discloses only one complete organometallic but it is a rhodium organometallic. Appeal Br. 5–7. Appellant acknowledges that Li discloses (CH3)3(CH3C5H4)Pt as a precursor compound, but argues “Li makes no mention of trapping and/or capturing (CH3)3(CH3C5H4)Pt.” Id. at 14; Reply Br. 7. These arguments do not properly address the Examiner’s rejection, which finds that Peck discloses trapping precursor material that can be a platinum organometallic compound. Final Act. 2; Peck ¶¶ 10, 60. Although Peck does not specifically disclose using (CH3)3(CH3C5H4)Pt, Li teaches using this compound as a precursor in a CVD process and that this compound allows for better step coverage during deposition. Li, 3:11–24, 4:45–55. Therefore, Li’s disclosure supports the Examiner’s rationale for modifying Peck to include (CH3)3(CH3C5H4)Pt as a precursor. Appellant further asserts that although the Examiner opines (CH3)3(CH3C5H4)Pt is expensive and this would have provided a reason to trap that compound, “there are many other techniques that may be used to Appeal 2019-005267 Application 12/235,147 9 more efficiently use the compound and thereby forego the expense of lost or unreacted compound.” Reply Br. 7. This argument is unpersuasive because it is mere attorney argument that fails to explain what these other techniques may be or why it would not have been obvious to modify Peck, which contemplates platinum organometallic precursors, to use Li’s specific platinum organometallic precursor, which Li describes as advantageous. As to the trapping temperatures, Appellant argues that organometallics other than the one Peck discloses “may require different temperatures and/or additional separations; none of which are predictable.” Appeal Br. 7. Appellant also contends that Peck discloses only one specific organometallic, Peck’s trapping temperatures regard that specific organometallic, and it is unreasonable to ignore Peck’s teachings “and simply plug in the physical parameters of the (CH3)3(CH3C5H4)Pt and opine that it will yield predictable results.” Id. at 16–17; Reply Br. 10–11. According to Appellant, the proposed modification to use (CH3)3(CH3C5H4)Pt as a precursor also involves a mixture that contains process gases and reaction byproducts, which would impact selecting the trapping and releasing temperatures. Appeal Br. 17. Thus, Appellant argues the rejection relies upon “a sizeable leap that can only be attributed to hindsight reconstruction.” Id. As noted above, Peck discloses the use of various organometallic precursors, including platinum organometallic compounds. Peck ¶¶ 10, 60. The Examiner also finds that Peck discloses a low temperature (e.g., -50°C) for its condenser to trap material. Final Act. 4; Peck ¶¶ 8, 17, 68. Therefore, Peck contemplates temperatures for trapping various compounds, including Appeal 2019-005267 Application 12/235,147 10 platinum organometallic compounds, and such temperatures can be less than about 0°C, as claim 63 recites. Claim 63 also recites that another trap is maintained at greater than 25°C to release trapped precursor. The Examiner does not find that Peck discloses this operating temperature for its condenser. However, Appellant acknowledges “Peck is clear that it is the vapor of the process gas that is most important when determining trapping temperatures.” Appeal Br. 16. Indeed, Peck teaches that when experimental data is not available, “vapor pressure data can be used to determine the optimum temperature which maximizes both retention of the desired component and separation selectivity.” Peck ¶ 25. The Examiner’s rejection appears to follow this reasoning, finding that Kodas teaches relatively high vapor pressure values for (CH3)3(CH3C5H4)Pt above 25°C. Final Act. 5; Kodas, 336. In other words, Kodas demonstrates temperatures at which (CH3)3(CH3C5H4)Pt would have a relatively high vapor pressure, which indicates a suitable temperature for releasing (CH3)3(CH3C5H4)Pt from a trap. In view of the above, Appellant does not identify a reversible error in the Examiner’s rejection of claim 63. Accordingly, we affirm the Examiner’s rejection of claims 63–70 under 35 U.S.C. § 103(a). Appeal 2019-005267 Application 12/235,147 11 CONCLUSION The Examiner’s rejection of claims 63–70 under 35 U.S.C. § 103(a) over Peck, Schmitt, Li, and Kodas is affirmed. In summary: Claims Rejected 35 U.S.C. § References/Basis Affirmed Reversed 63–70 103(a) Peck, Schmitt, Li, Kodas 63–70 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 Copy with citationCopy as parenthetical citation