Ex Parte Knoll

Patent Trial and Appeal BoardAug 29, 2017

13482685 (P.T.A.B. Aug. 29, 2017)

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. 13/482,685 05/29/2012 Heiko Knoll IXYS-01313 5900 47713 7590 08/29/2017 IMPERIUM PATENT WORKS P.O. BOX 607 Pleasanton, CA 94566 EXAMINER PATEL, DEVANG R ART UNIT PAPER NUMBER 1735 MAIL DATE DELIVERY MODE 08/29/2017 PAPER 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. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________ Ex parte HEIKO KNOLL ____________ Appeal 2016-008002 Application 13/482,6851 Technology Center 1700 ____________ Before TERRY J. OWENS, WESLEY B. DERRICK, and JEFFREY R. SNAY, Administrative Patent Judges. DERRICK, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE This is a decision on an appeal under 35 U.S.C. § 134 from the Examiner’s decision rejecting claims 1, 2, 4‒10, 12, and 16‒24.2 We have jurisdiction pursuant to 35 U.S.C. § 6. We REVERSE. 1 Appellant identifies IXYS Semiconductor GmbH as the real party in interest. Appeal Brief filed January 31, 2016 (“Appeal Br.”), 1. 2 Pending claims 3 and 11 stand withdrawn from examination. Appeal 2016-008002 Application 13/482,685 2 THE INVENTION Appellant’s appealed claims relate to a method of joining a metal- ceramic substrate having metallization to a metal body having a thickness of less than 1.0 mm using an aluminum-containing metal alloy having a liquidus temperature of greater than 450 °C. Specification filed May 29, 2012 (“Spec.”), Abstract. The Specification discloses that “[t]o join the metal-ceramic substrate and the metal body, the assembly comprising the metal-ceramic substrate, the metal alloy and the metal body is heated to a temperature of greater than 450 °C” (Spec. ¶ 63) and that “[t]he joining of ceramic substrate and metal body is advantageously carried out under an inert atmosphere” (Spec. ¶ 64). Each independent claim includes that “at least one metallized side” of the metal-ceramic substrate “contacts an inert gas atmosphere” during the joining of the metal-ceramic substrate and the metal body, as independent claims 1 and 21 require this during the recited heating and independent claim 16 requires this during the recited bonding. Claim 8, depending from claim 1, further requires that “the assembly [formed by the joining of the metal-ceramic substrate and the metal body] is at least partly coated with at least one of nickel, gold, and silver.” Claim 1 is representative. 1. A method of joining a metal-ceramic substrate to a metal body using a metal alloy, where the metal-ceramic substrate has metalization on at least one side, the method comprising: providing the metal body with a thickness of less than 1 mm; placing the metal alloy which contains aluminum and has a liquidus temperature of greater than 450°C between the metal- ceramic substrate and the metal body to form an assembly, Appeal 2016-008002 Application 13/482,685 3 wherein the metal-ceramic substrate is adapted to have a semiconductor component disposed on at least one metalized side of the metal-ceramic substrate, and wherein the metal- ceramic substrate includes a ceramic substrate and no more than two metal layers; and heating the assembly to a temperature of greater than 450°C such that the at least one metalized side of the metal- ceramic substrate contacts an inert gas atmosphere during heating. Appeal Br. 28 (Claims Appendix). THE REJECTIONS Claim 8 stands rejected under 35 U.S.C. § 112, second paragraph as being indefinite. Claims 1, 4‒7, 10, 12, 16‒18, and 24 stand rejected under 35 U.S.C. § 103(a) as unpatentable over Nagase ′7873 in view of Hirashima,4 as evidenced by Cusano.5 Claims 1, 2, 4‒7, 9, 10, 12, 16‒20, and 24 stand rejected under 35 U.S.C. § 103(a) as unpatentable over Nagase ′4816 in view of Sakuraba7 and Hirashima, as evidenced by Cusano. Claims 21‒23 stand rejected under 35 U.S.C. § 103(a) as unpatentable over Nagase ′481 in view of Yamashita,8 Sakuraba, and Hirashima, as evidenced by Cusano. 3 Nagase et al., US 6,033,787, issued March 7, 2000. 4 Hirashima et al., US 6,309,737 B1, published October 30, 2001. 5 Cusano et al., US 3,994,430, issued November 30, 1976. 6 Nagase et al., US 7,532,481 B2, issued May 12, 2009. 7 Sakuraba et al., US 6,054,762, issued April 25, 2000. 8 Yamashita et al., US 2010/0219228 A1, published September 2, 2010. Appeal 2016-008002 Application 13/482,685 4 DISCUSSION9 Having considered the Examiner’s rejections in light of Appellant’s arguments, we are persuaded that the Examiner has failed to meet the Office’s burden of establishing the unpatentability of the claims on appeal. For any ground of rejection, “the Examiner bears the initial burden . . . of presenting a prima facie case of unpatentability.” In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992). Indefiniteness The Examiner maintains that claim 8 is indefinite because “the limitation of coating another metal layer of nickel, gold or silver is conflicting in scope with previous claim 1, which recites the metal-ceramic substrate has no more than two metal layers,” and “it is ambiguous where exactly this metal coating is applied.” Final Act. 2. The Examiner further maintains that “[t]he ‘assembly’ is not a distinct element but rather a combination of the substrate, metal alloy and the metal body” and that, because of this, “it is ambiguous whether an additional metal layer (as required by claim 8) can be applied to the substrate.” Reply Br. 3‒4. Appellant argues, inter alia, that there is no conflict in scope because “the ‘metal-ceramic substrate’ and the ‘assembly’ are separate claim elements” and “that one of ordinary skill in the art would have understood with reasonable certainty . . . where the at least partial coating of nickel, gold, or silver recited in claim 8 is to be applied.” Appeal Br. 6‒7; see also Reply Br. 4‒6. 9 We refer to the Specification, the Final Office Action issued October 27, 2015 (“Final Act.”), the Appeal Brief, the Examiner’s Answer issued June 10, 2016 (“Ans.”), and the Reply Brief filed August 15, 2016 (“Reply Br.”). Appeal 2016-008002 Application 13/482,685 5 We do not sustain the Examiner’s rejection because we discern no conflict in scope or ambiguity that renders claim 8 indefinite. While claim 1 requires that the metal-ceramic substrate to be joined in the assembly has no more than two metal layers, it is silent as to coatings applied to the formed assembly, that is, to coatings applied once the metal-ceramic substrate has been joined to the metal body. It follows that claim 8, providing that “the assembly is at least partly coated,” does not conflict with claim 1 because the restriction to no more than two metal layers in the metal-ceramic substrate only applies to what is joined together to form the assembly, and does not bar further coating of the assembly, even when the further coating is applied to the portion of the assembly formed from the metal-ceramic substrate. The Examiner’s concern regarding where the metal coating is applied relates merely to breadth in the patterns of applied coatings, and breadth is not indefiniteness. See, e.g., In re Miller, 441 F.2d 689, 693 (CCPA 1971) (“Breadth is not . . . indefiniteness.”). Rejection over Nagase ′787 in view of Hirashima The Examiner relies on Nagase ′787 for its disclosure of a method of joining a metal-ceramic substrate to a metal body using a metal alloy where, referring to, inter alia, Figure 4, the Examiner relies on the metal-ceramic substrate formed of metallization 71 and 72 and ceramic substrate 73 as the metal-ceramic substrate, the plating 76A as the metal body, and aluminum foil 77/77A as the recited metal alloy containing aluminum positioned between the metal-ceramic substrate and the metal body, and for the heating of these components so arranged to a temperature of greater than 450 °C to join the metal-ceramic substrate and the metal body. Final Act. 3‒4 (citing, inter alia, Nagase ′787 col. 6, l. 25‒col. 7, l. 25, col. 8, ll. 30‒33, Figs. 4‒8). Appeal 2016-008002 Application 13/482,685 6 Figure 8, likewise, is cited for its metal layers 91 and 92 on ceramic substrate 93. Final Act. 3‒4. The Examiner also relies on Nagase ′787 for its disclosure relating to the joining of metal layers to ceramic substrate to form a metal-ceramic substrate in which the layers are “join[ed] by heating in an N2 atmosphere” (col. 6, ll. 50‒54) and for its disclosure relating to the joining of the metal-ceramic substrate to a heat sink by heating in a vacuum (col. 7, ll. 15‒16). In both joining processes, the structures to be joined are subjected to a load, i.e., force, pressing them together. Nagase ′787 col. 6, ll. 41‒42, 52‒54, col. 7, ll. 15‒17. The Examiner further finds that providing an inert atmosphere during heating was well-known in the bonding art to prevent oxidation, taking official notice, citing Hirashima for teaching bonding under vacuum or nitrogen atmosphere, and relying on Cusano as evidence. Final Act. 4 (citing Hirashima, Table 1, Cusano Abstract). The Examiner concludes that “it would have been obvious to a person of ordinary skill in the art at the time of the invention to provide an inert atmosphere during heating the multilayer assembly in the method of Nagase ′787 since such technique is conventional in the art and doing so would prevent oxidation” and that “at least portions of the metallizations 71/72 or 91/92 in Nagase ′787 would be in contact with inert gas since the entire assembly is exposed to the inert atmosphere.” Final Act. 4‒5. Addressing Appellant’s argument that the method of Nagase ′787 does not meet the recited limitation “that the at least one metalized side of the metal-ceramic substrate contacts an inert gas atmosphere” during the heating used to bond the metal-ceramic substrate to the metal body because there is a load applied to the assembly, and neither Hirashima nor Cusano Appeal 2016-008002 Application 13/482,685 7 remedies this deficiency (Appeal Br. 10‒13), the Examiner maintains that “[t]he vertical side surfaces of plate 72 (metallized side) in Nagase ′787 contacts the inert gas” and that the reference does not “state that the [applied] load is applied by physical contact of some object that covers the top surface.” Ans. 6. The Examiner further maintains that “even surrounding gas pressure can act as a load and thus, assembly exposed to inert gas of certain predetermined pressure would apply load, wherein the metallized sides of the substrate would contact the inert gas.” Ans. 6. Contrary to the Examiner’s position, the recited “at least one metalized side of the metal-ceramic substrate” does not encompass the edge of a metallization layer on the side of a metal-ceramic substrate because by the plain meaning of the terms the edge of such a metallization layer is not the metallized side. Rappaport v. Dement, 254 F.3d 1053, 1059 (Fed. Cir. 2001) (In interpreting the meaning of claims, turn first to the claims themselves.). Further, as highlighted by Appellant, the plain meaning of the independent claims “requires that the side of the metal-ceramic substrate that can receive a semiconductor component must contact the inert gas atmosphere during heating” and there is no basis for the vertical side surfaces being so adapted. Reply Br. 8‒10, 12. As to the Examiner’s position that a physical structure not covering the entire surface is not foreclosed by Nagase ′787 and that the load could be provided by exposure to inert gas of predetermined pressure, we find the Examiner has failed to proffer sufficient reasoning why less than complete coverage would be sufficient, or how gas pressure itself could provide the necessary force. On this record, accordingly, the Examiner’s articulated reasoning falls short of that necessary for a prima facie case. See In re Appeal 2016-008002 Application 13/482,685 8 Warner, 379 F.2d 1011, 1017 (CCPA 1967) (“The Patent Office has the initial duty of supplying the factual basis for its rejection. It may not . . . resort to speculation, unfounded assumptions or hindsight reconstruction to supply deficiencies in its factual basis.”); In re Sporck, 301 F.2d 686, 690 (CCPA 1962); see also Oetiker, 977 F.2d at 1445. We decline to scour the record in the first instance for facts that might support the rejection, as our primary role is review, not examination de novo. Rejection over Nagase ′481 in view of Sakuraba and Hirashima The Examiner relies on Nagase ′481 for its disclosure of a method of joining a metal-ceramic substrate to a metal body using a metal alloy where, referring to, inter alia, Figure 8, the Examiner relies on the metal-ceramic substrate formed of metallization 12 and 13 and ceramic substrate 11 as the metal-ceramic substrate, heat releasing element 31 as the metal body, and brazing material 33 as the recited metal alloy containing aluminum positioned between the metal-ceramic substrate and the metal body, and for the heating of these components so arranged to a temperature of greater than 450 °C to join the metal-ceramic substrate and the metal body. Final Act. 7 (citing Nagase ′481 col. 10, l. 44‒col. 11, l. 8, Fig. 8). While not relied on for disclosing an inert gas atmosphere during bonding by heating (Final Act. 8), Nagase ′481 manifestly discloses such a bonding process where power module base plate 32 can be the metal-ceramic substrate of metallization 12 and 13 and ceramic substrate 11 (Nagase ′481 col. 10, l. 61‒col. 11, l. 8). As in the rejection grounded on Nagase ′787, the Examiner finds that it was well-known to provide an inert atmosphere during heating to prevent oxidation, concludes that “it would have been obvious to a person of ordinary skill in the art at the time of the invention to provide an inert Appeal 2016-008002 Application 13/482,685 9 atmosphere during bonding the multilayer assembly in the method of Nagase ′481 since such technique is conventional in the art and doing so would prevent oxidation,” and further determines that “at least portions of the metallizations 12‒13 Nagase ′481 would be in contact with inert gas since the entire assembly is exposed to the inert atmosphere.” Final Act. 8‒9. Addressing Appellant’s argument that the method of Nagase ′481 does not meet the recited limitation “that the at least one metalized side of the metal-ceramic substrate contacts an inert gas atmosphere” because, as in Nagase ′787, the disclosed method applies a load during the heating (Appeal Br. 18‒19), the Examiner again maintains that “the vertical side surfaces of plate 12 also contact the inert gas,” that the reference does not “state that the load is applied by physical contact of some object,” and that “even surrounding gas pressure can act as a load and thus, assembly exposed to inert gas of certain predetermined pressure would apply load, wherein the metallized sides of the substrate would contact the inert gas.” Ans. 11. Further, the Examiner maintains that portions of the upper surface of plate 12 in Figure 8 of Nagase ′481 would still contact the inert gas during heating because chip 35 does not cover the entire surface. Ans. 11. On this record, the Examiner’s positions mirroring those set forth in the rejection over Nagase ′787 as to exposure to a vertical side surface, i.e., an edge, being sufficient, that nothing in the reference limits the applied load to that applied by physical contact, and that gas pressure could provide the load, are inadequate for the same reasons. As to the further reasoning grounded on the fact that chip 35 does not cover the entire surface, we find no sound basis articulated for heating any structure that includes chip 35 to greater than 450 °C. We further note that Appeal 2016-008002 Application 13/482,685 10 Nagase ′481 distinguishes between the attachment of the chip 35 to the power module base plate 32 from the joining of the power module base plate 32 to the heat releasing element 31 in that the former relies on a solder 34 and the latter a brazing material 33. Nagase ′481 col. 10, ll. Fig. 8. The Examiner’s reasoning provides no accounting of this difference. On this record, accordingly, the Examiner’s articulated reasoning falls short of that necessary for a prima facie case. See Warner, 379 F.2d at 1017; Sporck, 301 F.2d at 690; See also Oetiker, 977 F.2d at 1445. We decline to scour the record in the first instance for facts that might support the rejection, as our primary role is review, not examination de novo. Rejection over Nagase ′481 in view of Yamashita, Sakuraba, and Hirashima The Examiner relies on Nagase ′481 in the same manner as above in the rejection over Nagase ′481 in view of Sakuraba and Hirashima, and relies on Yamashita for its disclosure relating to a reflow furnace having a conveyor. Final Act. 13‒16. The Examiner likewise maintains the same positions as to the requirement that “the at least one metalized side of the metal-ceramic substrate contacts an inert gas atmosphere.” Final Act. 15‒16; Ans. 17‒18. On this record, accordingly, the Examiner’s articulated reasoning for the rejection of claims 21‒23 also falls short of that necessary for a prima facie case. Warner, 379 F.2d at 1017; Sporck, 301 F.2d at 690; see also Oetiker, 977 F.2d at 1445. We decline to scour the record in the first instance for facts that might support the rejection, as our primary role is review, not examination de novo. Appeal 2016-008002 Application 13/482,685 11 CONCLUSION The Examiner’s decision rejecting claims 1, 2, 4‒10, 12, and 16‒24 is REVERSED. REVERSED