Hexatech, Inc.Download PDFPatent Trials and Appeals BoardSep 2, 20212020004985 (P.T.A.B. Sep. 2, 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. 15/077,057 03/22/2016 Raoul Schlesser H63978 1070US.1 (0031.6) 4374 26158 7590 09/02/2021 WOMBLE BOND DICKINSON (US) LLP ATTN: IP DOCKETING P.O. BOX 7037 ATLANTA, GA 30357-0037 EXAMINER QI, HUA ART UNIT PAPER NUMBER 1714 NOTIFICATION DATE DELIVERY MODE 09/02/2021 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): BostonDocket@wbd-us.com IPDocketing@wbd-us.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte RAOUL SCHLESSER and EDWARD A. PREBLE Appeal 2020-004985 Application 15/077,057 Technology Center 1700 Before JEFFREY T. SMITH, JAMES C. HOUSEL, and N. WHITNEY WILSON, 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 1–3 and 9 under 35 U.S.C. § 103 as unpatentable over Schowalter (US 2007/0101932 A1, pub. May 10, 2007) in view of Morgan (US 2007/0243653 A1, pub. Oct. 18, 2007) and Moody (US 2012/0021175 A1, pub. Jan. 26, 2012). Non-Final Office Action (“Non- Final Act.”) dated Aug. 23, 2019, at 4–9. The Examiner has withdrawn pending claims 18–20 from consideration as directed to a non-elected invention. Id. at 1. We have jurisdiction under 35 U.S.C. § 6(b). 1 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42. Appellant identifies HexaTech, Inc. as the real party in interest. Appeal Brief (“Appeal Br.”) filed Jan. 22, 2020, at 1. Appeal 2020-004985 Application 15/077,057 2 We AFFIRM. CLAIMED SUBJECT MATTER The invention recited in the claims on appeal relates to processes of physical vapor transport (“PVT”) growth of single crystal aluminum nitride (“AlN”) articles via transport of AlN source material through a temperature gradient for deposition onto a seed crystal in a deposition zone. Specification (“Spec.”) filed March 22, 2016, at 1:15–17.2 Appellant discloses that, in such processes, the starting and evolving conditions of the AlN source material is critical to the end result, such as purity, density, grain/particle size, porosity, and thermal conductivity. Id. at 1:17–21. Appellant further discloses that it is desirable to exclude certain polycrystalline AlN production processes that cause crystal growth defects when used as source material in single crystal AlN growth by PVT. Id. at 2:3–5. According to Appellant, sintered AlN powder, which can have improved purity (e.g., 99.9%) and higher densities (e.g., 60–72%), is inadequate for use as source material in such PCT growth of single crystal AlN. Id. at 8–11. Appellant, therefore, discloses processes for the preparation of polycrystalline AlN source material including vapor, liquid, solid, and plasma growth methods, in particular, hydride vapor phase epitaxy (“HVPE”) and physical vapor deposition (“PVD”). Id. at 3:6–9 and 4:10–12. Independent claims 1 and 9, reproduced below from the Claims Appendix to the Appeal Brief, are illustrative of the claimed subject matter: 1. A process for producing a single crystal aluminum nitride article, the process comprising physical vapor transport (PVT) 2 This Decision also cites to the Examiner’s Answer (“Ans.”) dated April 21, 2020 and the Reply Brief (“Reply Br.”) filed June 19, 2020. Appeal 2020-004985 Application 15/077,057 3 growth of the single crystal aluminum nitride article by providing an AlN source material and an AlN seed within a reactor in a spaced apart orientation and heating the AlN source material in a manner sufficient to form volatilized species from the AlN source material for transport to the AlN seed, wherein the AlN source material is a polycrystalline hydride vapor phase epitaxy (HVPE) grown aluminum nitride mass or a polycrystalline physical vapor deposition (PVD) grown aluminum nitride mass such that the source material is defined by each of the following: a carbon content of less than 300 ppm; a silicon content of less than 300 ppm; an oxygen content of less than 300 ppm; an N/Al molar ratio of about 1; a relative density of at least 98%; an aluminum nitride purity of at least 99.9% by weight. 9. A process for producing an aluminum nitride (AlN) single crystal via vapor phase transport (PVT), the process comprising: providing an AlN source material and an AlN seed within a reactor in a spaced apart orientation; and heating the AlN source material in a manner sufficient to form volatilized species from the AlN source material for transport to the AlN seed; wherein the AlN source material comprises a grown polycrystalline AlN mass that has been grown to have a thickness of about 2.5 cm or greater, to have at least one lateral dimension of about 3 cm or greater, to have an N/Al molar ratio of about 1, to have a relative density of at least 98%, to have an aluminum nitride purity of at least 99% by weight, to have a carbon content of less than 300 ppm, to have a silicon content Appeal 2020-004985 Application 15/077,057 4 of less than 300 ppm, and to have an oxygen content of less than 300 ppm. OPINION We review the appealed rejection for error based upon the issues Appellant identifies, and in light of the arguments and evidence produced thereon. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010) (precedential), cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011) (“[I]t has long been the Board’s practice to require an applicant to identify the alleged error in the examiner’s rejections.”). After considering Appellant’s arguments and the evidence of record, we are not persuaded of reversible error in the stated rejection. Therefore, we affirm the Examiner’s obviousness rejection based substantially on the fact findings, reasoning, and conclusions set forth in the Non-Final Office Action and the Examiner’s Answer, which we adopt as our own. We offer the following for emphasis. The Examiner rejects claims 1–3 and 9 under 35 U.S.C. § 103 as unpatentable over Schowalter in view of Morgan and Moody. Non-Final Act. 4–9. Appellant argues claims 1 and 9 together. However, Appellant does not argue claims 2 and 3 separately. Therefore, we restrict our discussion below to the limitations of claims 1 and 9 only; claims 2 and 3 stand or fall with claim 1. The Examiner finds that Schowalter teaches a process for producing a single crystal AlN article comprising physical vapor transport (“PVT”) growth of the article from a polycrystalline AlN source material spaced apart from an AlN seed within a reactor, wherein the AlN source material is heated to volatilize species therefrom for transport and deposition on the Appeal 2020-004985 Application 15/077,057 5 AlN seed. Id. at 4, 7. The Examiner further finds that Schowalter’s polycrystalline AlN source material is high purity having an impurity concentration of less than about 500 ppm and a density approaching theoretical density. Id. The Examiner finds that Morgan teaches that it is desirable to use a polycrystalline AlN source having a purity as high as possible for growing single crystal AlN articles, such that the concentration of oxygen and other impurities may be less than approximately 100 ppm. Id. at 5; Morgan ¶ 49. The Examiner reasons that the concentration of any or each impurity element in the high purity source material would be less than about 500 ppm, and thus overlaps the recited range of less than 300 ppm. Id. at 4. The Examinerconcludes that it would have been obvious to have modified Schowalter’s polycrystalline AlN source material so as to have an oxygen content as low as possible, and preferably less than 100 ppm. Id. at 5. The Examiner further finds Schowalter teaches that HVPE may be successfully employed to produce AlN material in the disclosed process. Non-Final Act. 4. The Examiner concludes that it would have been obvious to have employed HVPE in Schowalter’s process to produce the AlN material as a known deposition method for this purpose. Id. Alternatively, the Examiner finds that the method used to produce that polycrystalline AlN source material is a process limitation, and Appellant has not shown that a source material grown by HVPE or PVD is structurally distinct from Schowalter’s source material. Id. at 6. In addition, the Examiner finds that because Schowalter’s polycrystalline AlN source material has a very high-purity with a density approaching the theoretical density, the source material has an N/Al molar Appeal 2020-004985 Application 15/077,057 6 ratio of about 1. Id. at 5, 7. However, the Examiner acknowledges that Schowalter and Morgan fail to expressly teach that the source material has a relative density of at least 98%, an AlN purity of at least 99.9 wt.%, a thickness of about 2.5 cm or greater, and a lateral dimension of about 3 cm or greater. Id. For these features, the Examiner finds that Moody teaches a polycrystalline AlN material having a thickness and diameter of at least 5 cm, a relative density of at least 98%, and a purity of at least 99.5, or as close as possible to 100% pure. Id. at 6, 8. The Examiner concludes that it would have been obvious to have modified Schowalter’s source material to have the highest possible density and purity, and a thickness and diameter, as taught by Moody in order to improve the single crystal AlN article. Id. Appellant argues that Schowalter fails to teach a polycrystalline AlN source material formed by HVPE. Appeal Br. 6; see also Reply Br. 2, 4. Appellant contends Schowalter teaches that single crystal AlN articles may be grown by sublimation/recondensation, molecular beam epitaxy (“MBE”), or HVPE, but does not teach that the polycrystalline AlN source material may be formed by HVPE. Appeal Br. 6. Appellant asserts that Schowalter instead teaches reacting pure Al with pure nitrogen and using sublimation transport to achieve near theoretical density, very high purity polycrystalline AlN source material. Id. (citing the Declaration under 37 C.F.R. § 1.132 of Raoul Schlesser (“Decl.”), filed May 17, 2019). Appellant urges that an ordinary artisan would not predict that Schowalter’s AlN source material “could be replace[d] with a polycrystalline AlN source material that is an HVPE grown or PVD grown material.” Id. at 6–7. Appellant further asserts that an ordinary artisan would understand that HVPE is not capable of depositing large volumes of polycrystalline AlN material. Id. at 7 (citing the Appeal 2020-004985 Application 15/077,057 7 Decl.). Appellant further contends that the Examiner fails to point to any teaching suggesting that an HVPE-grown or PVD-grown polycrystalline mass is capable of exhibiting each and every one of the recited properties in claims 1 and 9. Id. at 9–10. Appellant’s argument is not persuasive of reversible error. To begin, we note that Appellant fails to address the Examiner’s finding that the recitation that the AlN source material is HPVE or PVD grown is a product- by-process limitation. In this regard, we further note that Appellant has not shown that a polycrystalline AlN source material grown by HPVE or PVD is structurally different from Schowalter’s polycrystalline AlN source material. Nor does Appellant assert that the HVPE process for growing the source material is somehow a positive step of the process of producing single crystal AlN articles using the HVPE grown source material. Moreover, there is no dispute that Schowalter teaches that reacting pure Al with pure nitrogen and using sublimation transport to achieve near theoretical density, very high purity polycrystalline AlN source material. Indeed, Schowalter teaches that this source material may be formed by sublimation/recondensation. Schowalter ¶ 94. Such a process is a PVD growth process, one of two processes recited in claim 1 for forming the source material used in the claimed process. As such, Schowalter teaches a PVD-grown polycrystalline AlN source material. Alternatively, given Schowalter’s teaching that HVPE and MBE are alternative processes to such sublimation/recondensation for growing AlN masses, one of ordinary skill in the art would have reasonably expected that HVPE and MBE could be used as alternative growth processes to Schowalter’s sublimation/recondensation process for growing the Appeal 2020-004985 Application 15/077,057 8 polycrystalline AlN source material. Although, as Declarant states (Decl. ¶ 3), that Schowalter’s discussion of HVPE and MBE as alternatives to sublimation/recondensation is directed to forming the single crystal AlN article from the polycrystalline AlN source material, Schowalter does not teach that HVPE and MBE cannot be used as alternative growth processes to the sublimation/recondensation process taught for growing the source material. In this regard, we note that Declarant fails to explain why HVPE “is incapable of depositing large volumes of (polycrystalline) AlN material needed for source material production.” See Decl. ¶ 4. We note that Declarant merely states that “[p]roduction of large volumes of polycrystalline material requires an entirely different reactor setup with vastly different flow rates, temperatures, etc.” (id.), Declarant fails to state that, much less explain why, such HVPE production of polycrystalline AlN would have been outside of or was unknown to the ordinary skill in the art. Appellant next argues that the Examiner improperly disregarded the recited ranges for component impurities in finding that Schowalter’s disclosed ranges overlap the recited ranges. Appeal Br. 8. Appellant notes that Schowalter teaches that the source material has an impurity concentration lower than 500 ppm by weight, but fails to teach that “material may be excluded by this range.” Id. Appellant asserts that Schowalter teaches that aluminum suboxides may be generated due to the presence of oxygen in the source material, indicating that Schowalter’s source material may have as much as 499 ppm oxygen (or 499 ppm silicon or 499 ppm carbon). Id. Appellant contends that Schowalter never suggests limiting any of oxygen, silicon, or carbon to less than 300 ppm. Id. Appeal 2020-004985 Application 15/077,057 9 This argument is not persuasive of reversible error because Schowalter’s impurity concentration range of less than 500 ppm overlaps a concentration range for any impurity of less than 500 ppm. In other words, Schowalter’s range of 0–500 ppm (less than 500 ppm) overlaps claim 1’s range of 0–300 ppm (less than 300 ppm). As the Examiner indicates, “a prima facie case of obviousness typically exists when the ranges of a claimed composition overlap the ranges disclosed in the prior art.” E.I. DuPont de Nemours & Co. v. Synvina C.V., 904 F.3d 996, 1006 (Fed. Cir. 2018) (quoting In re Peterson, 315 F.3d 1325, 1329 (Fed. Cir. 2003)). Indeed, Schowalter’s total impurity concentration range of less than 500 ppm is narrower than claim 1’s total impurity concentration range of less than 900 ppm. In addition, Schowalter teaches that the polycrystalline AlN source material should have as high a purity as possible. Schowalter ¶¶ 94, 103. Morgan teaches production of high-purity, high-density polycrystalline AlN material, wherein sources of contaminants such as oxygen, water vapor, and hydrocarbons are reduced to less than 10 ppb to achieve impurity concentrations of less than 100 ppm. Morgan ¶¶ 41, 45, 49. Thus, Morgan suggests that it is not only possible, but even desirable, to achieve impurity concentrations of less than 100 ppm. Appellant fails to address either the Examiner’s findings regarding Morgan or the Examiner’s reasoning for combining the teachings of Schowalter and Morgan to achieve impurity concentrations less than 100 ppm. Appellant next argues that Moody has been improperly combined with Schowalter because Moody is incapable of providing Schowalter’s purity level (impurity concentration less than 500 ppm), much less the Appeal 2020-004985 Application 15/077,057 10 claimed purity level. Appeal Br. 10 (citing the Decl.) Appellant asserts that Moody teaches a polycrystalline AlN material with at least 98% purity by weight. Id. Appellant also contends that Moody’s product is sintered and allows up to 0.5% impurities (or 5000 ppm). Reply Br. 3–4. As such, Appellant contends that an ordinary artisan would not seek to combine Moody with Schowalter because Schowalter teaches away from Moody’s materials. Appeal Br. 10. This argument is also not persuasive of reversible error because it misapprehends the Examiner’s reliance on Moody’s teachings in the rejection. It is well established that the obviousness inquiry does not ask “whether the references could be physically combined but whether the claimed inventions are rendered obvious by the teachings of the prior art as a whole.” In re Etter, 756 F.2d 852, 859 (Fed. Cir. 1985) (en banc); see also In re Keller, 642 F.2d 413, 425 (CCPA 1981) (stating “[t]he test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference”). Although the argument and the Schlesser Declaration presume that the Examiner proposes to substitute Moody’s material for Schowalter’s in the process of producing single crystal AlN articles, the rejection instead relies on Moody in conjunction with Schowalter and Morgan to suggest that Schowalter’s polycrystalline AlN source material have a density as close as possible to theoretical density, such as at least about 98% thereof, and a purity as close to 100% as possible, such as 99.5% (or even the 99.95% Schowalter teaches when impurity concentration is less than 500 ppm, or even the 99.99% Morgan teaches when impurity concentration is less than 100 ppm). Appeal 2020-004985 Application 15/077,057 11 In addition, Declarant fails to establish via persuasive technical reasoning or sufficient supporting data that Moody is incapable of producing an AlN source material having an oxygen content less than 300 ppm. See Decl. ¶ 7. Declarant premises this conclusion on Moody’s disclosure that residual impurities are mostly related to oxygen originating from surface oxides in the starting powder. Id. However, Moody explains that choice of particle surface area influences product purity such that greater surface area can increase oxidation potential and oxygen content in the final product. Moody ¶ 34. As such, Moody suggests that product purity may be controlled by reducing particle surface area and teaches that product density can be balanced against product purity. Id.; see also id. ¶ 42. Neither Appellant nor Declarant directs our attention to any teaching in Moody suggesting that product purities close to 100% and product densities of at least 98% of theoretical density cannot be achieved. Accordingly, we sustain the Examiner’s obviousness rejection of claims 1–3 and 9 over the combined teachings of Schowalter, Morgan, and Moody. CONCLUSION Upon consideration of the record and for the reasons set forth above and in the Non-Final Office Action and the Examiner’s Answer, the Examiner’s decision to reject claims 1–3 and 9 under 35 U.S.C. § 103 as unpatentable over Schowalter in view Morgan and Moody is affirmed. Appeal 2020-004985 Application 15/077,057 12 DECISION SUMMARY In summary: Claim(s) Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 1–3, 9 103 Schowalter, Morgan, Moody 1–3, 9 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) (2019). AFFIRMED Copy with citationCopy as parenthetical citation