Petition for Inter Partes Review of U.S. 7,060,360
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`UNITED STATES PATENT AND TRADEMARK OFFICE
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`———————
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`———————
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`
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`General Electric Company,
`Petitioner,
`
`v.
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`United Technologies Corporation,
`Patent Owner
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`———————
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`
`
`
`
`PETITION FOR INTER PARTES REVIEW
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`OF
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`U.S. PATENT NO. 7,060,360
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`Petition for Inter Partes Review of U.S. 7,060,360
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`Table of Contents
`I. MANDATORY NOTICES ............................................................................. 1
`A.
`Real Party-in-Interest ............................................................................ 1
`B.
`Related Matters ...................................................................................... 1
`C.
`Lead and Back-up Counsel and Service Information ........................... 1
`II. GROUNDS FOR STANDING ........................................................................ 1
`III.
`INTRODUCTION ........................................................................................... 2
`A.
`Technology Overview ........................................................................... 4
`1.
`Engine Materials: High-Temperature Oxidation
`Resistance ......................................................................... 4
`Engine Materials: Environmental Barrier Coatings ................... 7
`2.
`Prosecution History of the 360 Patent ................................................... 9
`B.
`The 360 Patent Claims ........................................................................ 12
`C.
`IV. STATUTORY GROUNDS FOR THE CHALLENGES .............................. 14
`V.
`CLAIM CONSTRUCTION .......................................................................... 16
`A.
`“refractory metal disilicide/silicon eutectic” (claim 1 et al.) .............. 16
`B.
`“bond layer” (claims 1, 5, 7, and 9) .................................................... 17
`IDENTIFICATION OF HOW THE CLAIMS ARE
`UNPATENTABLE ........................................................................................ 18
`A. Overview of the Prior Art .................................................................... 18
`1.
`Terentieva .................................................................................. 18
`2.
`Eaton 456 .................................................................................. 20
`3. Webster ..................................................................................... 21
`4.
`Suzuki ........................................................................................ 21
`B. Ground 1: Claims 1-14 of the 360 Patent are rendered obvious
`under 35 U.S.C. § 103 by Terentieva in view of Eaton 456 ............... 22
`1.
`Claim 1 ...................................................................................... 22
`2.
`Claims 2 and 3 ........................................................................... 30
`3.
`Claim 4 ...................................................................................... 31
`4.
`Claim 5 ...................................................................................... 32
`
`VI.
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`Petition for Inter Partes Review of U.S. 7,060,360
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`Claim 6 ...................................................................................... 33
`5.
`Claim 7 ...................................................................................... 34
`6.
`Claim 8 ...................................................................................... 35
`7.
`Claim 9 ...................................................................................... 35
`8.
`Claim 10 .................................................................................... 36
`9.
`10. Claims 11-14 ............................................................................. 36
`C. Ground 2: Claims 1-14 of the 360 Patent are rendered obvious
`under 35 U.S.C. § 103 by Terentieva in view of Webster,
`Suzuki and Admitted Prior Art............................................................ 39
`1.
`Claim 1 ...................................................................................... 39
`2.
`Claims 2 and 3 ........................................................................... 44
`3.
`Claim 4 ...................................................................................... 44
`4.
`Claim 5 ...................................................................................... 45
`5.
`Claim 6 ...................................................................................... 45
`6.
`Claim 7 ...................................................................................... 46
`7.
`Claim 8 ...................................................................................... 46
`8.
`Claim 9 ...................................................................................... 46
`9.
`Claim 10 .................................................................................... 47
`10. Claims 11-14 ............................................................................. 47
`VII. CONCLUSION .............................................................................................. 48
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`Petition for Inter Partes Review of U.S. 7,060,360
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`Table of Exhibits
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`GE-1001
`
`U.S. Patent No. 7,060,360 to Eaton et al.
`
`GE-1002
`
`Prosecution File History of U.S. Patent No. 7,060,360.
`
`GE-1003
`
`Declaration of Dr. Andreas M. Glaeser Under 37 C.F.R. § 1.68.
`
`GE-1004
`
`Curriculum Vitae of Dr. Andreas M. Glaeser.
`
`GE-1005
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`U.S. Patent No. 5,677,060 to Terentieva et al.
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`GE-1006
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`U.S. Patent No. 6,387,456 to Eaton et al.
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`GE-1007
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`GE-1008
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`GE-1009
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`GE-1010
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`GE-1011
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`GE-1012
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`GE-1013
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`GE-1014
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`GE-1015
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`A.K. Vasudévan & J.J. Petrovic, A Comparative Overview of
`Molybdenum Disilicide Composites, Materials Science and
`Engineering, vol. A155, Nos. 1-2 (Jun. 1992), pp. 1-17.
`European Patent App. No. 1142850 A1 to Wang et al.
`(“Wang”).
`U.S. Patent No. 6,517,341 to Brun et al. (“Brun”).
`
`D.R. Clarke & C.G. Levi, Materials Design for the Next
`Generation Thermal Barrier Coatings, 33 Annu. Rev. Mater.
`Res., Apr. 18, 2003, pp. 383-417.
`K.N. Lee, Current Status of Environmental Barrier Coatings for
`Si-Based Ceramics, Surface and Coatings Technology, vols.
`133-134 (Nov. 2000) pp. 1-7.
`N. Bornstein, Oxidation of Advanced Intermetallic Compounds,
`Journal de Physique IV, vol. 3, No. C9 (Dec. 1993), pp. C9-367-
`73.
`U.S. Patent No. 5,985,470 to Spitsberg et al. (“Spitsberg”).
`
`K.N. Lee et al., Environmental Barrier Coatings for Silicon-
`Based Ceramics, High Temperature Ceramic Matrix
`Composites, 4th Int’l Conf. on High Temp. Ceramic Matrix
`Composites (HT-CMC4), Oct. 1-3, 2001.
`R. Gibala et al., Mechanical behavior and interface design of
`MoSi2-based Alloys and Composites, Materials Science and
`Engineering, vol. A155, No. 1-2 (Jun. 1992) pp.147-158.
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`iii
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`GE-1016
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`GE-1017
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`GE-1018
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`GE-1019
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`GE-1020
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`GE-1021
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`GE-1022
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`GE-1023
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`GE-1024
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`GE-1025
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`GE-1026
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`Petition for Inter Partes Review of U.S. 7,060,360
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`Dilip M. Shah, MoSi2 and Other Silicides as High Temperature
`Structural Materials, Superalloys (1992) pp. 409-422.
`J.-C. Zhao & J. H. Westbrook, Ultrahigh-Temperature
`Materials for Jet Engines, MRS Bulletin, vol. 28, No. 9 (Sep.
`2003) pp. 622-626.
`M. Tsirlin et al., Experimental Investigation of Multifunctional
`Interphase Coatings on SiC Fibers for Non-Oxide High
`Temperature Resistant CMCs, High Temperature Ceramic
`Matrix Composites, 4th Int’l Conf. on High Temp. Ceramic
`Matrix Composites (HT-CMC4), Oct. 1-3, 2001.
`Nathan S. Jacobson, Corrosion of Silicon-Based Ceramics in
`Combustion Environments, J. Am. Ceram. Soc., vol. 76, No. 1
`(Jan. 1993) pp. 3-28.
`Paul J. Jorgensen et al., Effects of Water Vapor on Oxidation of
`Silicon Carbide, J. Am. Ceram. Soc., vol. 44, No. 6 (Jun. 1961)
`pp. 258-261.
`Yongdong Xu et al., Oxidation Behavior and Mechanical
`Properties of C/SiC Composites with Si-MoSi2 Oxidation
`Protection Coating, J. Mater. Sci., vol. 34, No. 24, pp. 6009-14
`(Dec. 1999).
`S. Kamakshi Sundaram et al., Molten Glass Corrosion
`Resistance of Immersed Combustion-Heating Tube Materials in
`E-Glass, J. Am. Ceram. Soc., vol. 78, No. 7 (Jul. 1995) pp.
`1940-46.
`Y. L. Jeng, E. J. Lavernia, Processing of Molybdenum
`Disilicide, J. Mater. Sci., vol. 29, No. 10, pp. 2557-2571 (Jan.
`1994).
`Yoshikazu Suzuki et al., Improvement in Mechanical Properties
`of Powder-Processed MoSi2 by the Addition of Sc2O3 and Y2O3,
`J. Am. Ceram. Soc., vol. 81, No. 12 (Dec. 1998) pp. 3141-49.
`J. D. Webster et al., Oxidation Protection Coatings for C/SiC
`Based on Yttrium Silicate, J. Eur. Cer. Soc., vol. 18, No. 16
`(Dec. 1998) pp. 2345-50.
`J.J. Petrovic et al., Molybdenum Disilicide Materials for Glass
`Melting Sensor Sheaths, 25th Annual Conf. on Composites,
`Advanced Ceramics, Materials, and Structures: A, Ceramic
`Engineering and Science Proceedings, vol. 22, No. 3 (Jan. 2001)
`pp. 59-64.
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`GE-1027
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`GE-1028
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`GE-1029
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`Petition for Inter Partes Review of U.S. 7,060,360
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`H. Kahn et al., Fracture toughness of polysilicon MEMS
`devices, Sensors and Actuators, vol. 82, No. 1-3 (May 2000) pp.
`274-80.
`C.L. Muhlstein et al., A reaction-layer mechanism for the
`delayed failure of micron-scale polycrystalline silicon structural
`films subjected to high-cycle fatigue loading, Acta Materialia,
`vol. 50, No. 14 (Aug. 2002) pp. 3579-95.
`S. Kamakshi Sundaram et al., Molten Glass Corrosion
`Resistance of Immersed Combustion-Heating Tube Materials in
`Soda-Lime-Silicate Glass, J. Am. Ceram. Soc., vol. 77, No. 6
`(Jun. 1994) pp. 1613-23.
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`Petition for Inter Partes Review of U.S. 7,060,360
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`I. MANDATORY NOTICES
`A. Real Party-in-Interest
`The real parties-in-interest are General Electric Company (Petitioner),
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`
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`Snecma S.A., CFM International S.A., CFM International, Inc., and Safran S.A.
`
`B. Related Matters
`As of the filing of this Petition and to the best knowledge of the Petitioner,
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`
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`U.S. Patent No. 7,060,360 (“the 360 Patent”) is not involved in litigation.
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`C. Lead and Back-up Counsel and Service Information
`Petitioner designates Anish Desai (Reg. No. 73,760), available at 1300 Eye
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`
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`Street NW, Suite 900, Washington, DC 20005 (T: 202-682-7103) as lead counsel,
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`and Brian E. Ferguson (Reg. No. 36,801) (T: 202-682-7103) and Megan H.
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`Wantland (Reg. No. 64,423) (T: 202-682-7271), available at the same address, as
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`back-up counsel. Please address all correspondence to both lead and back-up
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`counsel. Petitioner consents to service by electronic email at the following email
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`address: GE.360.IPR@weil.com.
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`II. GROUNDS FOR STANDING
`Petitioner certifies that the 360 Patent is available for inter partes review and
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`that Petitioner is not barred or estopped from requesting inter partes review
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`challenging the patent claims on the grounds identified in this Petition.
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`III.
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`Petition for Inter Partes Review of U.S. 7,060,360
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`INTRODUCTION
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`The 360 Patent is entitled “Bond Coat for Silicon Based Substrates” and
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`describes the invention as “an improved bond layer for use on a silicon based
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`substrate.” GE-1001 at 1:52-53. According to the specification, the bond layer of
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`the invention “comprises an alloy comprising a refractory metal disilicide/silicon
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`eutectic.” Id. at 1:53-54. The originally filed claims (1-15) were directed to this
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`alleged invention, i.e., a refractory metal disilicide/silicon eutectic layer on a
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`silicon substrate. GE-1002.066. However, these claims were rejected as
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`anticipated by U.S. 5,677,060 (“Terentieva”). See id. at .045-.048 (finding
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`Terentieva’s refractory silicide coating Ti(0.4-0.95)Mo(0.6-0.05)Si2 and healing eutectic
`
`phase anticipated the claimed bond layer refractory metal disilicide/silicon
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`eutectic). The Patent Owner amended the claims to require an additional “barrier
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`layer” on top of the refractory metal disilicide/silicon eutectic layer. GE-1002.036-
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`.043. But, these first amended claims were again rejected as anticipated by
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`Terentieva. GE-1002.029-.033. In response, the Patent Owner amended the
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`claims a second time to require an “environmental barrier layer selected from the
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`group consisting essentially of an alkaline earth aluminosilicate based on barium
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`and strontium, and yttrium silicate.” GE-1002.020-.026. The claims were allowed
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`without further rejection. Id. at .009-.015. Thus, the Patent Owner was able to
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`gain allowance by adding the requirement of an environmental barrier layer
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`Petition for Inter Partes Review of U.S. 7,060,360
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`consisting of a barium-strontium aluminosilicate or yttrium silicate.
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`
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`The 360 Patent, however, acknowledges in the “Background of the
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`Invention” that prior art systems disclose a bond layer between a silicon substrate
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`and an environmental barrier layer such as an alkaline earth aluminosilicate based
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`on barium and strontium, or yttrium silicate. GE-1001 at 1:19-24 (“With reference
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`to FIGS. 1a and 1b, prior art environmental barrier coatings form a composite 10
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`comprising a silicon based substrate 12, a bond coat or layer 14 such as a dense
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`continuous layer of silicon metal, a barrier layer 16 such as either an alkaline earth
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`aluminosilicate based on barium and strontium, or yttrium silicate”). Indeed, the
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`use of such environmental barrier layers was well known in the art to protect
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`underlying silicon-containing components from volatizing in the high temperature,
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`aqueous environments found in gas turbine engines. GE-1003 at ¶¶ 23-26.
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`As explained in detail in this Petition, the second amended claims should not
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`have been allowed because it would have been obvious to combine an
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`environmental barrier layer consisting of alkaline earth aluminosilicate based on
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`barium and strontium or yttrium silicate with a refractory metal disilicide/silicon
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`eutectic layer. The prior art discloses a clear motivation to combine an
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`environmental barrier layer consisting of an alkaline earth aluminosilicate based on
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`barium and strontium or yttrium silicate with the silicon-containing materials
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`disclosed in Terentieva in order to protect those silicon-containing materials from
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`Petition for Inter Partes Review of U.S. 7,060,360
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`water vapor attack in high temperature applications. The prior art also discloses
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`that one of ordinary skill would have had a reasonable expectation of success in
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`adding a known environmental barrier layer to the silicon-containing materials
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`disclosed in Terentieva. Accordingly, the amended claims of the 360 Patent
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`simply claim the application of a known technique (an environmental barrier layer)
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`to a known article (silicon-containing materials) that yields a predictable result
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`(protecting the silicon containing materials from water vapor attack in high
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`temperature applications). Petitioner accordingly requests that the Board institute
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`inter partes review of claims 1-14, and cancel these claims as invalid as obvious.
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`A. Technology Overview1
`1.
`Engine Materials: High-Temperature Oxidation Resistance
`Engine efficiency and performance are largely dependent on the
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`
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`temperatures reached in the combustion and turbine sections of a gas turbine
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`engine. GE-1017.003; see also GE-1008 at 1:10-12 (“Higher operating
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`temperatures for gas turbine engines are continuously sought in order to increase
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`their efficiency.”). For example, “[t]o achieve higher thrust, higher operating
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`1 This section is based on prior art to the 360 Patent. The expert declaration of Dr.
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`Andreas Glaeser includes a more in-depth overview of the technology. GE-1003 at
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`¶¶ 19-26, 44-59.
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`temperatures must be realized.” GE-1017.003-.004. Accordingly, the high
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`temperature capabilities of hot section components are critical. See, e.g., GE-
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`1007.001 (directly relating engine maintenance costs with “the selection of reliable
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`high temperature materials”); see also GE-1008 at 1:12-14 (“[A]s operating
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`temperatures increase, the high temperature durability of the components of the
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`engine must correspondingly increase.”).
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`
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`The need for components with high temperature capabilities initially led to
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`the development of nickel-based superalloys, which have excellent oxidation
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`resistance and mechanical properties for applications up to around 1000ºC. GE-
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`1007.002. However, the high density of these superalloys led to the proposal of
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`silicon-based ceramic materials for high temperature section components. Id.
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`Silicon-based ceramics are less dense and exhibit excellent oxidation resistance at
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`temperatures between 1000ºC and 1600ºC. Id.; see also GE-1009 at 1:25-28
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`(“These silicon-containing materials are particularly appealing because of their
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`excellent high temperature properties and lower density.”); GE-1009 at 1:47-55
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`(“A primary advantage then of silicon-containing ceramics or silicon-containing
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`composites . . . over metals is their superior high temperature durability which
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`enable higher turbine rotor inlet temperatures. [Additionally], they exhibit low
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`coefficient of thermal expansion and lower density in comparison to nickel-base
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`superalloys.”).
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`In addition to silicon-based ceramics, materials based on aluminide and
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`silicide compositions were also actively investigated for use in high temperature
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`engine applications. GE-1007.002 (describing the low densities, high melting
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`points, and high thermal conductivities of aluminide and silicide matrix composites
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`as attractive characteristics for use in high temperature environments). In
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`particular, material composites designed around MoSi2 were found to have high
`
`melting points and excellent high temperature oxidation resistance. GE-1007.005-
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`.006. As described in the prior art, the intermetallic compound molybdenum
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`disilicide (MoSi2) was first considered as a high temperature coating material for
`
`protecting ductile metal components in commercial heating applications. GE-
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`1007.003. By the 1970s, silicides such as MoSi2 were also being considered as
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`coating materials for gas turbine engines. GE-1007.003; see also GE-1005 at 2:48-
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`67 (disclosing a protective coating containing MoSi2 to protect against oxidation at
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`surface temperatures as high as 1850º C).
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`
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`Despite its excellent oxidation resistance, the low temperature brittleness of
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`MoSi2 limited its structural applications. GE-1007.007 (“The major problem
`
`impeding the use of MoSi2 is its mechanical properties.”). One known way to
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`overcome this problem was to create a MoSi2 composite material with a second-
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`phase thermodynamically compatible reinforcement. GE-1007.007, .010; see also
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`GE-1016.003 (“Here the major driver for compositing [silicides] is lack of room
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`temperature toughness rather than strength.”); GE-1003 at ¶ 23. “Many important
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`ceramic reinforcements are thermodynamically stable with MoSi2.” GE-1007.005.
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`Such ceramic reinforcements have been shown to improve the fracture toughness
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`of MoSi2. GE-1007.011. Prior to the filing of the 360 Patent, “[c]ontinual
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`improvements were made in the mechanical properties of SiC-MoSi2 composites,
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`through a number of generations of composite materials.” GE-1007.004
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`(describing that in the 1980s researchers began examining SiC-MoSi2 composites
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`for aerospace applications).
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`Engine Materials: Environmental Barrier Coatings
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`2.
`To survive high temperature, highly oxidative environments, silicon-based
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`
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`materials form a dense protective silica (SiO2) scale on the surface, which acts as a
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`barrier for the underlying silicon-containing material to prevent diffusion of O2.
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`GE-1011.001 (“Silicon-based ceramics exhibit excellent oxidation resistance in
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`clean, dry oxygen, by forming a slow-growing, dense silica scale [1].”); see also
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`GE-1009 at 2:17-19. Unfortunately, this protective scale deteriorates in the
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`presence of water or water vapor such as steam. See, e.g., GE-1011.001 (“[T]he
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`normally protective silica scale can be severely degraded by reacting with
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`impurities, such as alkali salts [2] or water vapor [3].”); GE-1014.022 (“Silicon-
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`based ceramics, however, suffer from rapid surface recession in combustion
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`environments due to volatilization of the silica scale via reaction with water
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`vapor.”); GE-1010.005 (describing the presence of steam as “partly a direct result
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`of the generation of water during the combustion process, but in a number of
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`designs it is a consequence of the use of steam injection to enhance turbine
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`efficiency”). In particular, silica volatilizes in the presence of steam to form
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`gaseous SiO and Si(OH)x, ultimately resulting in the recession and material loss of
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`the silicon-containing material itself. See GE-1003 at ¶¶ 23-24. The use of barrier
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`coatings to protect the underlying silicon-containing component from the harsh
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`environments found in gas turbine engines is well established in the prior art. See
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`GE-1014.022 (“[Environmental barrier coatings] are absolute necessity for the
`
`protection of Si-based ceramics from water vapor.”); GE-1011.001 (describing key
`
`issues for selecting an environmental barrier coating for silicon-based ceramics
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`used in the hot section of gas turbine engines); GE-1013 at 1:53-58 (“[S]uch
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`coatings can provide environmental protection by inhibiting the major mechanism
`
`for degradation of silicon carbide in a corrosive environment, namely, the
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`formation of volatile silicon monoxide (SiO) and silicon hydroxide (Si(OH)4)
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`products.”); GE-1019.001 (indicating the same issues apply to “SiO2-forming
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`alloys, such as molybdenum disilicide (MoSi2)”); see also GE-1003 at ¶¶ 25-26,
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`74.
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`The 360 Patent admits that environmental barrier coatings made of
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`composites of various protective layers—often with each layer having different
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`chemical and mechanical properties—which, together, work to protect the
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`underlying silicon-containing substrate from accelerated oxidation in high
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`temperature, aqueous environments were known in the prior art. GE-1001 at 1:10-
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`34. In particular, the 360 Patent describes prior art environmental barrier coatings
`
`as comprising a barrier layer “such as either an alkaline earth aluminosilicate based
`
`on barium and strontium, or yttrium silicate.” GE-1001 at 1:19-24. The use of a
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`barrier layer made of barium-strontium-aluminosilicate (“BSAS”) or yttrium
`
`silicate is also described in multiple prior art references. See, e.g., GE-1006 at
`
`2:42-46, 3:8-13 (describing BSAS as a preferred barrier layer capable of
`
`“inhibit[ing] the formation of gaseous species of silicon when the article is exposed
`
`to a high temperature, aqueous environment”); GE-1011.004 (“The improved
`
`water vapor durability with the composite bond coat and the BSAS top coat was
`
`attributed to the excellent crack resistance of these coatings.”); GE-1013 at 2:61-54
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`(“[T]he BSAS bond coat will continue to provide a level of environmental
`
`protection to the underlying SiC-containing substrate.”); GE-1025.004 (“The
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`development of protective coatings based on a SiC bonding layer combined with
`
`an outer yttrium silicate erosion resistant layer and oxygen barrier is described.”).
`
`Prosecution History of the 360 Patent
`
`B.
`The 360 Patent issued from U.S. Patent Application No. 10/443,342 (“the
`
`
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`342 Application”), filed on May 22, 2003, and does not claim priority to any other
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`patent applications.
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`Petition for Inter Partes Review of U.S. 7,060,360
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`
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`Claim 1 as originally filed required “[a]n article comprising a silicon based
`
`substrate and a bond layer, the bond layer comprises an alloy comprising a
`
`refractory metal disilicide/silicon eutectic.” GE-1002.066. This claim, as well as
`
`dependent claims 2-15, was rejected as anticipated by Terentieva. GE-1002.045-
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`.048.
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` The Patent Owner subsequently amended claim 1 to include a barrier layer:
`
`“[a]n article comprising a silicon based substrate, at least one barrier layer, and a
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`bond layer between the substrate and the barrier layer, the bond layer comprises an
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`alloy comprising a refractory metal disilicide/silicon eutectic.” GE-1002.037. In
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`addition, Patent Owner argued that the claimed system “addresses the problem of
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`accelerated oxidation of silica and silica formers in high temperature steam
`
`environments,” and that “this accelerated oxidation problem is not at all
`
`understood or considered by the teachings of [Terentieva].” GE-1002.040-.043.
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`Claims 1-15 were once again rejected as anticipated by Terentieva. GE-1002.029-
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`.033.
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`
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`In response to the Final Rejection, Patent Owner amended claim 1 as
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`follows: “[a]n article comprising a silicon based substrate, at least one
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`environmental barrier layer selected from the group consisting essentially of an
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`alkaline earth aluminosilicate based on barium and strontium, and yttrium silicate,
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`and a bond layer between the substrate and the environmental barrier layer, the
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`Petition for Inter Partes Review of U.S. 7,060,360
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`bond layer comprises an alloy comprising a refractory metal disilicide/silicon
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`eutectic.” GE-1002.021. Following an interview with the examiner, claims 1-14
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`were allowed. GE-1002.012-.015, .024. Below is an illustration showing the
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`structures2 that were rejected and allowed by the examiner:
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`The requirement for an environmental barrier layer consisting of BSAS or
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`yttrium silicate came, not from any description of the invention of the 360 Patent,
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`but rather, from the description of the prior art in the “Background of the
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`Invention.” GE-1001 at 1:19-26. There is no discussion in the file history
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`addressing the obviousness of combining an environmental barrier layer with a
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`2 The layer above the “bond layer” in the structure on the left is shown with dashed
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`lines because the originally filed claims did not include any limitation for a third
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`layer. However, the use of the term “bond layer” implies the use of a third layer,
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`such that the bond layer is between the third layer and the silicon substrate. GE-
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`1003 at ¶ 43.
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`refractory metal disilicide/silicon eutectic layer.
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`Petition for Inter Partes Review of U.S. 7,060,360
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`C. The 360 Patent Claims
`Claim 1 of the 360 Patent is reproduced below:
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`1. An article comprising a silicon based substrate,
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`at least one environmental barrier layer selected from the group
`consisting essentially of an alkaline earth aluminosilicate based on
`barium and strontium, and yttrium silicate, and
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`a bond layer between the substrate and the environmental
`barrier layer, the bond layer comprises an alloy comprising a
`refractory metal disilicide/silicon eutectic.
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`Dependent claims 2 and 3 require that the refractory metal disilicide is
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`selected from the group consisting of disilicides of “molybdenum, chromium,
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`hafnium, niobium, rhenium, tantalum, titanium, tungsten, uranium, vanadium,
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`yttrium and mixtures thereof.” GE-1001 at 2:63-3:5.
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`Dependent claim 4 requires that the refractory metal disilicide/silicon
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`eutectic have a melting point of greater than 1300ºC. Id. at 3:6-8.
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`Dependent claim 5 requires that the bond layer comprise a multiphase
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`microstructure of the refractory metal disilicide/silicon eutectic and silicon. Id. at
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`3:9-11. Dependent claim 6 further requires that the article of claim 5 have a
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`fracture toughness greater than 1MPa·m½. Id. at 3:12-13.
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`Dependent claim 7 requires that the bond layer comprise a multiphase
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`microstructure of the refractory metal disilicide/silicon eutectic and refractory
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`metal disilicide. Id. at 3:14-17. Dependent claim 8 further requires that the article
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`Petition for Inter Partes Review of U.S. 7,060,360
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`of claim 7 have a fracture toughness greater than 1MPa·m½. Id. at 3:18-19.
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`Dependent claim 9 requires that the bond layer comprise a multiphase
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`microstructure of the refractory metal disilicide/silicon eutectic and one of silicon
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`and refractory metal disilicide. Id. at 4:1-4. Dependent claim 10 further requires
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`that the article of claim 9 have a fracture toughness greater than 1MPa·m½. Id. at
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`4:5-6.
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`Dependent claims 11 and 12 require the article of claims 1 and 9,
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`respectively, to have silicon present in an amount greater than or equal to 66.7
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`atomic percent. Id. at 4:7-12.
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`Dependent claims 13 and 14 require the article of claims 1 and 9,
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`respectively, to have silicon present in an amount greater than or equal to 80
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`atomic percent. Id. at 4:13-18.
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`As discussed in further detail herein, environmental barrier coatings,
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`including the environmental barrier layer and bond layer recited in the 360 Patent
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`claims, were disclosed in prior art and obvious to use for silicon based substrates.
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`Petition for Inter Partes Review of U.S. 7,060,360
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`IV. STATUTORY GROUNDS FOR THE CHALLENGES
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`This Petition provides the following challenges:
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`Ground 1 Obviousness of claims 1-14 under 35 U.S.C. § 103 based U.S. Patent
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`No. 5,677,060 (“Terentieva”) (GE-1005) in view of U.S. Patent No.
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`6,387,456 (“Eaton 456”) (GE-1006).
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`Ground 2 Obviousness of claims 1-14 under 35 U.S.C. § 103 based U.S. Patent
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`No. 5,677,060 (“Terentieva”) (GE-1005) in view of J.D. Webster et
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`al., Oxidation Protection Coatings for C/SiC Based on Yttrium
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`Silicate (“Webster”) (GE-1025), Yoshikazu Suzuki et al.,
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`Improvement in Mechanical Properties of Powder-Processed MoSi2
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`by the Addition of Sc2O3 and Y2O3 (“Suzuki”) (GE-1024), and the
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`Admitted Prior Art in the 360 Patent.
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`Terentieva is a U.S. Patent that issued on October 14, 1997, and is prior art
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`under § 102(b). GE-1005. Eaton 456 is a U.S. Patent that issued on May 14, 2002,
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`and is prior art under § 102(b). GE-1006.
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`Webster is a report published in the December 1998 issue of the Journal of
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`the European Ceramic Society, from Corrosion of Ceramics, 5th Conference of the
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`European Ceramic Society in Versailles, France, 1997, and is prior art under
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`§102(b). GE-1025. As shown by the date stamps on the face of GE-1025, the
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`periodical containing the Webster report was received by the Engineering Library
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`at the University of Washington on March 11, 1999. GE-1025.001. Suzuki is an
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`Petition for Inter Partes Review of U.S. 7,060,360
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`article published in the December 1998 issue of the Journal of the American
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`Ceramic Society, and is prior art under § 102(b). GE-1024. As shown by the date
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`stamps on the face of GE-1024, the periodical containing Suzuki was received by
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`the Engineering Library at the University of Washington on January 8, 1999. GE-
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`1024.001. As noted by Dr. Glaeser, both the Journal of the American Ceramic
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`Society and the Journal of the European Ceramic Society are published monthly.
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`GE-1003 at ¶¶ 64, 66.
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`While Terentieva was previously before the USPTO during the prosecution
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`of the 360 Patent, Petitioner respectfully requests that Terentieva be considered
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`anew in combination with Eaton 456 or with Webster and Suzuki—none of which
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`were previously cited to the examiner during prosecution of the 360 Patent. Thus,
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`Terentieva in combination with either Eaton 456 or Webster and Suzuki form
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`combinations which have never been considered and which are not substantially
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`the same as those previously presented to the examiner during prosecution.
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`Petitioner notes that Grounds 1 and 2 are not redundant, and therefore,
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`requests institution on both grounds. Specifically, the Grounds separately show the
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`obviousness of the two different environmental barrier layers claimed in the 360
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`Patent.
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`Petition for Inter Partes Review of U.S. 7,060,360
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`V. CLAIM CONSTRUCTION
`In an inter partes review, “[a] claim in an unexpired patent shall be given its
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`broadest reasonable construction in light of the specification of the patent in which
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`it appears.” 37 C.F.R. § 42.100(b). Petitioner has applied this standard in
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`proposing constructions for the terms “refractory metal disilicide/silicon