Case IPR2016-00782
`U.S. Patent No. 6,784,552
`Attorney Docket No. ________
`
`
`Filed on behalf of DSS TECHNOLOGY MANAGEMENT, INC.
`By:
`James C. Gumina (gumina@mbhb.com)
`
`Michael D. Clifford (clifford@mbhb.com)
`
`Michael D. Anderson (andersonm@mbhb.com)
`
`McDonnell Boehnen Hulbert & Berghoff LLP
`
`300 South Wacker Drive
`
`Suite 3200
`
`Chicago, Illinois 60606
`
`Tel.: (312) 913-0001
`
`Fax: (312) 913-0002
`
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`____________________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`____________________
`
`SAMSUNG GROUP
`Petitioner,
`
`
`
`
`
`v.
`
`DSS TECHNOLOGY MANAGEMENT, INC.,
`Patent Owner.
`
`_____________
`
`Case IPR2016-00782
`Patent 6,784,552
`
`______________
`
`PATENT OWNER RESPONSE TO PETITION
`FOR INTER PARTES REVIEW OF U.S. PATENT NO. 6,784,552
`
`
`
`

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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
`Attorney Docket No. ________
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`Page(s)
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`
`
`TABLE OF CONTENTS
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`
`
`I.
`II.
`
`Introduction ...................................................................................................... 7
`Background ...................................................................................................... 9
`A.
`The ‘552 Patent ..................................................................................... 9
`Overview ..................................................................................... 9
`1.
`2.
`Prosecution History ................................................................... 13
`3.
`Illustrative Claims ..................................................................... 14
`4.
`Claim Construction ................................................................... 15
`5.
`Grounds in Petition ................................................................... 16
`Kuesters ............................................................................................... 17
`B.
`Havemann ............................................................................................ 18
`C.
`D. Heath.................................................................................................... 19
`III. The Petition Fails to Identify Objective Evidence of Unpatentability
`and Instead Relies Upon the Conclusory Declaration of Richard Fair ......... 22
`IV. Neither Claim 1 Nor Claim 8 of the ‘552 Patent Is Anticipated by
`Kuesters ......................................................................................................... 25
`A.
`Claim 1 of the ‘552 Patent Is Not Anticipated by Kuesters ................ 27
`Claim 8 of the ‘552 Patent Is Not Anticipated by Kuesters ................ 34
`B.
` V. Claims 2, 4-7, and 9-12 of the ‘552 Patent Are Also Anticipated by
`Kuesters ......................................................................................................... 35
`VI. Neither Claim 1 Nor Claim 8 of the ‘552 Patent Is Obvious Over the
`Combinations of Kuesters and Heath ............................................................ 35
`A.
`Claim 1 of the ‘552 Patent Is Not Obvious Over the
`Combinations of Kuesters and Heath .................................................. 36
`VII. Claims 2 and 4-7 of the ‘552 Patent Are Also Not Obvious Over the
`Combinations of Kuesters and Heath ............................................................ 43
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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
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`VIII. Claim 3 of the ‘552 Patent Is Not Obvious Over the Combinations of
`Kuesters, Heath, and Havemann .................................................................... 44
`IX. Conclusion ..................................................................................................... 46
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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
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`TABLE OF AUTHORITIES
`
`
`
`Page(s)
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`Cases
`Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (en banc). ...................... 15
`In re Rambus, 694 F.3d 42, 46 (Fed. Cir. 2012) .................................................... 15
`Dynamic Drinkware, LLC v. National Graphics, Inc., 800 F.3d 1375, 1378
`(Fed. Cir. 2015). ................................................................................................ 25
`In re Omeprazole Patent Litigation, 281 Fed. Appx. 974, 979 (Fed. Cir.
`2008) ................................................................................................................. 26
`Medtronic, Inc. v. Norred, M.D., Case IPR2014-00111, 2015 WL 1906726,
`at *9 (PTAB Apr. 23, 2015) ............................................................................. 26
`Verdegaal Bros. v. Union Oil Co., 814 F.2d 628, 631 (Fed. Cir. 1987) ............... 26
`Richardson v. Suzuki Motor Co., 868 F.2d 1226, 1236 (Fed. Cir. 1989) .............. 26
`Net MoneyIN, Inc. v. VeriSign, Inc., 545 F.3d 1359, 1371 (Fed. Cir. 2008) ......... 26
`Biodelivery Scis. Int’l, Inc., Petitioner, IPR2014-00325, 2014 WL 3767600,
`at *3 (July 29, 2014) ......................................................................................... 28
`Allergan, Inc. v. Barr Labs., Inc., 501 F. App’x 965, 972 (Fed. Cir. 2013) .......... 28
`InTouch Techs., Inc. v. VGO Commc’ns, Inc., 751 F.3d 1327, 1347 (Fed.
`Cir. 2014) .................................................................................................... 35, 36
`Graham v. John Deere Co.
`383 U.S. 1 (1966) .............................................................................................. 35
`Intelligent Bio-Systems, Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359,
`1366 (Fed. Cir. 2016) ........................................................................................ 36
`
`Statutes
`35 U.S.C. § 102 .............................................................................................. passim
`35 U.S.C. § 103 .............................................................................................. passim
`35 U.S.C. § 361 .............................................................................................. passim
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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
`Attorney Docket No. ________
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`Secondary Sources
`Kuesters et al., Self Aligned Bitline Contact For 4 Mbit dRAM, Proceedings
`of the First International Symposium on Ultra Large Scale Integration
`Science and Technology, 640-49 (1987) .................................................. passim
`Federal Circuit Bar Association Model Patent Jury Instruction A.5 (Feb.
`2012) ................................................................................................................. 26
`Office Patent Trial Practice Guide, 77 Fed. Reg. 48,756, 48,763 (Aug. 14,
`2012) ................................................................................................................. 28
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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
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`Exhibit List
`
`DSS
`Exhibit #
`DSS.2001 U.S. Patent No. 6,784,552 (“552 Patent”), 8/31/2004
`
`Description
`
`DSS.2002 Decision Instituting Review, 9/23/2016
`
`DSS.2003
`
`‘552 Patent Original Application, 3/31/2000
`
`DSS.2004 Amendment to ‘552 Patent, 3/31/2004
`
`DSS.2005 Notice of Allowance, 4/20/2004
`
`DSS.2006 Request for Reconsideration and Amendment, 2/6/2004
`
`DSS.2007
`
`DSS.2008
`
`Petition for Inter Partes Review, 3/18/2016
`Kuesters et al., “Self Aligned Bitline Contact For 4 Mbit dRAM,”
`Proceedings of the First International Symposium on Ultra Large
`Scale Integration Science and Technology, 1987, pp. 640-649
`(“Kuesters”)
`DSS.2009 U.S. Patent No. 4,686,000 (“Heath”), 8/11/1987
`
`DSS.2010 U.S. Patent No. 5,482,894 (“Havemann”), 1/9/1996
`
`DSS.2011 Declaration of Dr. Richard Fair (“Fair Declaration”), 3/18/2016
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`
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`I.
`
`Introduction
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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
`Attorney Docket No. ________
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`Patent owner DSS Technology Management, Inc., a wholly owned
`
`subsidiary of Document Security Systems, Inc., (“Patent Owner” or “DSS”)
`
`respectfully files this Patent Owner Response to the Petition (“Response”) in
`
`opposition to the Petition filed for inter partes review (“Petition”) of U.S. Patent
`
`No. 6,784,552 (the “‘552 Patent”) (Ex. 2001).
`
`Put simply, the prior art cited in the Petition, either alone or in combination,
`
`does not teach the structure claimed in the ‘552 Patent. The combination of cited
`
`art does not expressly teach or suggest a semiconductor device with a lateral
`
`insulative spacer portion that: 1) is “boxy”; 2) has a side with “an angle relative to
`
`the substrate surface that is either a right angle or an acute angle of more than 85°”;
`
`3) retains a portion of the etch stop material adjacent to the spacer portion to ensure
`
`increased insulation for the polysilicon layer from the conductive contact; and 4)
`
`has only a small portion removed during the etch. See ’552 Patent, figure 4(k)
`
`(annotated, provided below).
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`Furthermore, the cited art does not teach or suggest the specific low-selectivity
`
`etching method of manufacture taught in the ‘552 Patent to achieve the structure
`
`recited in claims 1 and 8 of the ‘552 Patent.
`
`To the contrary, Kuesters,1 the sole reference cited in Petitioner’s § 102(b)
`
`argument, teaches a different structure that is made with a highly-selective etch
`
`process. Moreover, contrary to Petitioner’s § 103(a) assertions, the combination of
`
`references does not address the deficiencies of Kuesters and does not teach one
`
`skilled in the art at the time of invention each and every element claimed in the
`
`‘552 Patent.
`
`In an effort to cure the deficiencies of the art, the Petitioner relies heavily on
`
`the conclusory and result-oriented analysis of Dr. Richard Fair. As discussed in
`
`detail below, however, the cited references which are, at best, merely cumulative
`
`of the prior-art figures already cited in the Background of the Invention portion of
`
`the ‘552 Patent, do not support the conclusions of Dr. Fair or render the claims of
`
`the ‘552 Patent invalid.
`
`
`1 Kuesters et al., Self Aligned Bitline Contact For 4 Mbit dRAM, Proceedings of the
`
`First International Symposium on Ultra Large Scale Integration Science and
`
`Technology, 640-49 (1987) (“Kuesters”).
`
`8
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`Accordingly, since the subject matter claimed in the ‘552 Patent is not taught
`
`in the prior art, whether read alone or in combination, the Petitioner has not made a
`
`prima facie showing of anticipation or obviousness for any of the claims in the
`
`‘552 Patent.
`
`II. Background
`
`
`
`A. The ‘552 Patent
`
`United States Patent No. 6,784,552 Patent, entitled Structure Having
`
`Reduced Lateral Spacer Erosion, was issued to James E. Nulty et al., on August
`
`31, 2004, and was a division of application No. 08/577,751, filed on December 22,
`
`1995, which is now U.S. Patent No. 6,066,555.
`
`
`
`1. Overview
`
`The teachings of the ‘552 Patent’s specification is generally directed to “a
`
`process of semiconductor device fabrication and a structure of a semiconductor
`
`device having ‘substantially rectangular’ lateral insulating spacers adjacent to gate
`
`electrodes.2 Decision Instituting Review, at 3 (Ex. 2002) (citing ’552 Patent, at
`
`
`2 As the Board also notes, the ’552 Patent recites: “The phrase ‘substantially
`
`rectangular’ means that a side of the spacer has an angle relative to the substrate
`
`surface of more than 85°.” See Decision Instituting Review, at 3; (quoting ’552
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`Patent, at col. 8, ll. 40–42).
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`Abstract). The claims of the ‘552 Patent are, however, directed to a semiconductor
`
`device with a particular structure. In particular, a structure wherein a side of an
`
`insulating spacer has an angle relative to the substrate surface that is either a right
`
`angle or an acute angle of more than 85°. See ‘552 Patent, at 14:29-31 (claim 1)
`
`and 14:65-67 (claim 8). Of significant importance, however, the ‘552 Patent
`
`details that such a structure is not obtainable by ordinary method and that a low-
`
`selectivity etch allows one to obtain the claimed structural features.
`
`This teaching is evidenced when comparing the figures 4(I) and 4(J),
`
`with a close-up of the differences in the figures being highlighted in figure 4(k).
`
`
`
`
`The ‘552 Patent describes that after utilizing the low-selectivity etch: 1) “a[n]
`
`[insulating] layer spacer portion [] retains a rectangular or ‘boxy’ profile,” ’552
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`10
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`Patent, at 13:4-6;3 2) “a side of the insulating spacer has an angle relative to the
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`Case IPR2016-00782
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`substrate surface that is either a right angle or an acute angle of more than 85°,” id.
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`at 14:29-31; 3) “does not remove all of the etch stop material adjacent to the spacer
`
`portion,” id. at 12:59-60;4 and 4) removes “a small portion [] (illustrated in ghost
`
`lines) of the [insulating] layer spacer portion,” id. at 13:7-8. For reference, an
`
`annotated version of figure 4(k), highlighting these differences, is provided below.
`
`
`
`
`3 See also ‘552 Patent, at 13:11-14 (“It is to be appreciated that the described etch
`
`stop layer etch conditions (i.e., low selectivity, low bombardment/high neutral
`
`flux) are exemplary of etch conditions that result in the retention of a boxy
`
`spacer.”).
`
`4 Retaining this portion of the etch stop material through low-selectivity etching
`
`provides an “additional spacer material to insulate the polysilicon layer [] from a
`
`conductive contact that will subsequently be added to the contact opening.” Id. at
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`11
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`63-65.
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`The structure of the ‘552 Patent obtained with a low-selectivity etch is at
`
`least in part distinct from the prior because, when utilizing such a highly-selective
`
`etch (as used in the prior art), the spacer portion adjacent to the contact region is
`
`almost always transformed into a sloped spacer. See, e.g., ‘552 Patent, at 4:61-
`
`5:17; compare id. at figure 2(A) with id. at figure 2(B) (both provided below).
`
`
`Thus the prior art’s highly-selective etch does not result in the claimed angle
`
`
`
`
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`between the insulating spacer and the substrate. Moreover, as described in the
`
`prior art, after the high selectivity etching was completed, the contact opening was
`
`cleaned with a sputter etchant, which further eroded a critical portion of the sloped
`
`insulating spacer even further increasing the possibility of a short circuit. Id. at
`
`5:35-41; compare id. at figure 2(B) with id. at figure 3 (both provided below).
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`
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`Thus, in the prior art cited in the ‘552 Patent for creating self-aligned contact
`
`structures, the diagonal thickness of the spacer, rather than the vertical thickness of
`
`the insulating layer, determined the minimum insulating layer thickness for the
`
`gate, which negatively impacts the number, integrity, and insulative effectivity of
`
`the structures created therefrom. Id. at 6:8-12.
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`
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`2. Prosecution History
`
`As originally filed, the claims of the ‘552 Patent were directed to a transistor
`
`structure with a “substantially rectangular” lateral spacer portion adjacent to a
`
`contact opening. See Ex. 2003, at 28-32. Over the course of the prosecution,
`
`however, the applicants made clear that: “The phrase ‘substantially rectangular’
`
`means that a side of the spacer has an angle relative to the substrate surface of
`
`more than 85°.” See, e.g., Ex. 2004, at 2.
`
`Furthermore, the applicants amended the independent claims to reflect this
`
`aspect of the invention, further requiring: “wherein a side of the insulating spacer
`
`has an angle relative to the substrate surface that is either a right angle or an acute
`
`angle of more than 85°.” Id. at 3-4.
`
`In light of these amendments, the claims were allowed. See Ex. 2005.
`
`Moreover, the applicants explained that the prior art methods “use[d] etchants with
`
`high selectivity” that, in contrast to the claims of the ‘552 Patent, would
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`“transform a substantially rectangular spacer adjacent to the contact region into a
`
`sloped spacer.” Ex. 2006, at 4 (emphasis added).
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`
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`3. Illustrative Claims
`
`Petitioner challenges the validity of all 12 of the claims contained in the ‘552
`
`Patent; but, of these claims only claims 1 and 8 are independent. Claim 1, reads:
`
`1. A structure, comprising:
`(a)
`a conductive layer disposed over a substrate;
`(b)
`a first insulating layer on the conductive layer:
`(c)
`a contact region in said first insulating layer;
`(d)
`at least one insulating spacer in the contact region adjacent to the first
`insulating layer; and
`an etch stop material over said first insulating layer and adjacent to the
`insulating spacer, the etch stop material being a different material
`from the insulating spacer,
`wherein a side of the insulating spacer has an angle relative to the substrate
`surface that is either a right angle or an acute angle of more than 85°.
`
`Claims 2–7 depend directly or indirectly from claim 1. Claim 8 also recites the
`
`(e)
`
`final and distinguishing element of claim 1:
`
`8. A structure, comprising . . .
`wherein a side of the electrically insulative spacer has an angle relative to
`the substrate surface that is either a right angle or an acute angle of
`more than 85°.
`Claims 9-12 depend directly or indirectly from claim 8.
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`Case IPR2016-00782
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`4. Claim Construction
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`As correctly identified by the Board, the ’552 Patent has expired, and thus
`
`
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`
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`the claims should be construed in accordance with the standard set forth in Phillips
`
`v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (en banc). See also In re Rambus,
`
`694 F.3d 42, 46 (Fed. Cir. 2012) (“While claims are generally given their broadest
`
`possible scope during prosecution, the Board’s review of the claims of an expired
`
`patent is similar to that of a district court’s review.”).
`
`In the Board’s decision instituting inter partes review, when construing the
`
`claims of the ‘552 Patent, the claim construction issue presented in the Petition was
`
`to “construe a pair of related claim terms, which are ‘contact region’ and ‘contact
`
`opening’ recited in claims 1 and 8, respectively.” Decision Instituting Review at 7-
`
`9 (citing Petition for Inter Partes Review, 13-14 (Ex. 2007)). Specifically, the
`
`Petitioner asserted “that a person of ordinary skill in the art would have understood
`
`that the ordinary and customary meaning of ‘contact region’ or ‘contact opening’ is
`
`‘contact opening or via’ in the context of the ’552 Patent because the ’552 Patent
`
`expressly defines the terms as ‘contact openings and/or via[s].’” Id. at 8 (citing
`
`Petition for Inter Partes Review, at 14 and the ‘552 Patent, at 1, 2:38-41).
`
`Without adopting or accepting any of Petitioners’ accompanying arguments,
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`DSS does not dispute the ultimate claim constructions proposed by Petitioner as to
`
`the meaning of “contact region” versus “contact opening” for purposes of this
`
`proceeding.
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`5. Grounds in Petition
`
`The Petitioner challenges all of the claims of the ‘552 Patent on the
`
`following grounds:
`
`a. Claims 1, 2, 4-12 are allegedly anticipated by Kuesters (Ex. 2008);
`b. Claims 1, 2, 4-7 are allegedly obvious over Kuesters and U.S. Patent No.
`4,686,000 (“Heath”) (Ex. 2009); and
`c. Claim 3 is allegedly Claim 3 is allegedly obvious over Kuesters, Heath,
`and U.S. Patent No. 5,482,894 (“Havemann”) (Ex. 2010).5
`
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`
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`5 As the Board noted, Petitioner also claims that Claim 3 is allegedly obvious over
`
`Kuesters and Havemann; but, the Petitioner has also argued that “the reasons for
`
`combining Kuesters with Heath or Havemann individually discussed above are
`
`equally applicable to the three-way combination of Kuesters, Heath, and
`
`Havemann.” See Board Decision at 26 (citing Petition for Inter Partes Review, at
`
`30-31 (citing Fair Declaration, at ¶¶ 121-123)). Thus, DSS finds no compelling
`
`reason to address the allegedly obviousness of Claim 3 over the combination of
`
`Kuesters and Havemann separately from the analysis concerning the combination
`
`of Kuesters, Heath, and Havemann addressed below.
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`B. Kuesters
`
` Kuesters describes “a process of fabricating a 4 Mbit dRAM semiconductor
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`
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`device with a 25% reduction in cell size, ‘achieved by a self aligned bitline
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`contact.’” Decision Instituting Review, at 12 (citing Kuesters, at 3). For the
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`purposes of this proceeding, however, the relevant teaching of Kuesters is
`
`contained in two figures.
`
`First, figure 2 of Kuesters, provides an idealized illustration of the structure
`
`resulting from the dry etch utilized to create the contact hole. Specifically, at
`
`figure 2-2, a layer of “thin oxide/nitride/oxide” is shown, in which the nitride layer
`
`functions as the etch stop material for the dry etch. See Kuesters, at 5, 8, and figure
`
`2-2 (provided below). Then, after the dry etch is complete, the finalized contact
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`hole is shown at figure 2-3. Id. at 5, 8, and figure 2-3 (provided below).
`
`
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`After the formation of the finalized contact hole, a conductive material is deposited
`
`in the contact hole, which does not alter the structure of the finalized contact hole
`
`as detailed as illustrated in figure 2-4 (provided below).
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`Second, figure 4 of Kuesters purports to provide an SEM (scanned electron
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`
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`microscopy) image of the actual finalized contact hole structure resulting from the
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`process described in Kuesters. See id. 5, 9, and figure 4a (provided below).
`
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`This image, although difficult to interpret, is the primary basis for Petitioner’s
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`arguments surrounding the final element of independent claims 1 and 8 of the ‘552
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`Patent.
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`
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`C. Havemann
`
`The invention disclosed in Havemann is generally “directed at the
`
`fabrication of semiconductor devices and more particularly to the formation of
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`self-aligned contacts on such devices.” See Havemann at 1:23-25.
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`In relevant part, Havemann discloses a process in which two conductive
`
`gates are covered with a thermally-grown oxide layer comprising an insulating cap
`
`and sidewall spacers. See Havemann, at 2:40-45, 5:10-15, 6:11-14. Next, a silicon
`
`nitride etch stop material is deposited over the insulating cap and the sidewall
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`spacers and a dielectric layer is deposited over the etch stop material. See
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`Havemann at 2:46-49 and 2:52-54. Havemann then discloses a method for
`
`creating finalized contact openings through, “anisotropic etch[ing] by known
`
`methods to remove conformal dielectric [] (and possibly gate oxide []) from
`
`horizontal exposed surfaces.” See id. at 24 (citing Havemann at 5:6-9).
`
` Havemann also discloses an “O2 plasma etch” that is utilized “to remove
`
`organic-containing material from insulated gap 29” due to its “extremely high
`
`selectivity,” resulting in the finalized contact hole disclosed in figures 2C and 2D
`
`(provided below). See Havemann at 5:19-21 and 5:39-41 (emphasis added);
`
`figures 2C and 2D.
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`
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`Once the contact opening has been formed, conductive material is then
`
`deposited in the contact hole, which does not alter the finalized structure of the
`
`contact hole whatsoever. See id. at 5:40-45.
`
`D. Heath
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`The invention disclosed in Heath, generally, is an “improved process for
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`self-aligned contact window formation in an integrated circuit.” See Heath, at
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`Abstract. In relevant part, Heath discloses a process in which an insulative layer
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`24 is formed above (24b, which is “relatively thick”) and below (24a, which is
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`“relatively thin”) a conductive gate layer 16. See Heath, at 9:52-55. Furthermore,
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`in the embodiment addressed by the Petitioner, Heath discloses “a sidewall spacer .
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`. . formed illustratively of oxide,” that “remains in the structure after completion of
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`the circuit,” Heath 10:18-25, and which is overlaid with an “[e]tch stop material 10
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`. . . composed of nitride,” Heath, at 9:63-67.This structure is most easily observed
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`in figure 8C of Heath (provided below).
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`Following the formation of this structure, an “anisotropic dry etch is
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`performed to open a contact window,” with the “part of [etch stop] layer 10
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`between dashed lines 56 [] removed” as well as “the then-exposed parts of oxide
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`24a and 24b.” Heath, at 10:1-5.
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`The ultimate structure taught in Heath has a lateral spacer portion (16a) that
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`“is 0.1-0.3 pm thick.”6 See Heath, at 10:23-30. Furthermore, Heath teaches that
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`6 It is also worth noting that Heath, discloses a large, conventional sidewall
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`spacer—on the order of 0.1-0.3μm (1000-3000 Å)—which is one of the exact
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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
`Attorney Docket No. ________
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`the spacer “may or may not be thick enough to provide reliable insulation between
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`gate electrode 16 and metal subsequently deposited in [the] contact window.” Id.
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`(emphasis added). Indeed, Heath teaches that the finalized structure “may be
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`formed in such a way that the [insulative] spacer is removed . . . leaving no
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`material on the side wall of gate electrode . . . because the present invention in its
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`preferred form provides adequate insulation between gate electrode 16 and
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`subsequently deposited [conductive contact] by leaving the ’stick’ 10a of layer 10
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`issues the ‘552 Patent addresses. Specifically, the ‘552 patent states that
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`“eliminating alignment sensitivity for conventional small feature size structures,
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`including self-aligned contact structures, requires a final [] minimum insulating
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`spacer of more than 500 Å and preferably on the order of 1000-1500 Å or greater
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`to fulfill requirements for an adequate process margin, complete gap fill, and
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`device reliability.” ’552 Patent, at 2 (emphasis added). The ‘552 Patent, on the
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`other hand, in a preferred embodiment, discloses a sidewall spacer having a
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`thickness of 400 Å and “substantially rectangular portions.” Id. at 13:53-58.
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`Therefore, the structure disclosed in Heath falls into the conventional category of
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`structures that the invention described in the ‘552 Patent remedies by yielding a
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`smaller, lateral, and more uniformly shaped 400 Å spacer.
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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
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`of protect the side wall of the gate electrode.” See id. at 10:30-41 (emphasis
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`added); see also id. at figure 8C (provided below).
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`Thus, the need for any sidewall portion is obviated by the process taught in
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`Heath because “the sidewall of the gate electrode [is] not determinative of the
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`isolation of the gate electrode from the subsequently deposited metal,” due to the
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`stick layer of etch stop material left post-etching. Id. at 10:41-44.
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` Finally, once the contact opening has been formed, conductive material is
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`deposited in the contact hole, which does not alter the finalized structure of the
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`contact hole whatsoever. See id. at 12:42-43.
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`III. The Petition Fails to Identify Objective Evidence of Unpatentability and
`Instead Relies Upon the Conclusory Declaration of Richard Fair
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`
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`The prior art cited in the Petition does not disclose the elements of the
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`claimed structure of the ‘552 Patent. For example, the prior art never provides any
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`express discussion of an insulative lateral spacer portion that has “a side” with “an
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`angle relative to the substrate surface that is either a right angle or an acute angle
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`of more than 85°” as disclosed in the ‘552 Patent. Indeed, Petitioners never point
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`to any such discussion in the art. Instead, the Petition relies heavily on the
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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
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`declaration of Dr. Richard Fair. However, a review of Dr. Fair’s Declaration
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`makes clear that pivotal portions consist of little more than conclusory statements
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`on the key issues. Such unsupported statements should not be considered as
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`objective evidence sufficient to meet Petitioner’s burden.
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`For example, in discussing the relative angle of the insulative lateral spacer
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`portion, Dr. Fair cited figure 4(a) of Kuesters.
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`In this discussion, he superimposed color on figure 4a of Kuesters purportedly
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`
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`corresponding with the layers in the structure in figure 4(a) and added his own
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`lines allegedly showing the key interface between the substrate and the insulating
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`spacer (provided below). See Fair Declaration, at 35-36 (Ex. 2011).
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`Dr. Fair then posited (without any guidance from the art itself) that “[t]he angle of
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`a side of the insulating spacer relative to the substrate surface can be measured
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`where it contacts the pale green of the substrate,” and that he “measured this angle
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`for the left sidewall spacer (as annotated below) and found that the angle was
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`between 86° and 87°.” Id. at 38.
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`Finally, based on his own annotations, Dr. Fair concluded that “the SEM in Figure
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`
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`4a clearly discloses an angle of a side of the sidewall spacer relative to the
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`substrate of greater than 85°.” Id. (emphasis added). Petitioner relies on this
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`statement, alone, to support its argument that this element of claims 1 and 8 is
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`disclosed in the lone prior art cited.
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`The problems created by Dr. Fair’s analysis, however, are manifest. First,
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`Kuesters nowhere discloses a preferred angle for the insulative space portion to the
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`substrate surface. Thus, Dr. Fair’s analysis is based on review of angle from one
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`lone figure, figure 4a in Kuesters, that was not intended to relate, much less teach,
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`the information Dr. Fair attempts to pull from the figure.
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`Second, as the parameters or methods for obtaining figure 4(a) are not
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`disclosed in Kuesters, Dr. Fair is reduced to employing a seemingly arbitrary
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`Case IPR2016-00782
`U.S. Patent No. 6,784,552
`Attorney Docket No. ________
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`coloring exercise to clarify these structures, and their significance, in his annotated
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`version of the figure.
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`Third, and perhaps most significant, Dr. Fair then superimposed his own
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`angle graphic over the “left sidewall spacer,” which he, unsurprisingly, found to be
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`“between 86° and 87°.” The glaring omission in his declaration, however, was that
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`Dr. Fair did not provide any substantive basis for the angle he drew or how he
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`measured it. This omission is especially curious because, as Dr. Fair
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`acknowledges, the SEM he relies upon was not taken at a 90° angle to the
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`structure. See Fair Declaration, at 37. Thus there is no clear perspective of the
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`angle at which the insulator side wall meets the substrate. Dr. Fair’s analysis
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`appears, at best, to be a rough approximation by Dr. Fair, and at worst, a result-
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`oriented analysis intended to invalidate the ‘552 Patent.
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`IV. Neither Claim 1 nor Claim 8 of the ‘552 Patent Is Anticipated by
`Kuesters
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`“The burden of proof is on the Petitioner to prove ‘unpatentability by a
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`preponderance of the evidence,’ 35 U.S.C. § 316(e), and that burden never shifts to
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`the patentee.” Dynamic Drinkware, LLC v. National Graphics, Inc., 800 F.3d
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`1375, 1378 (Fed. Cir. 2015) (emphasis added). “A pr