`571-272-7822
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`Paper 9
`Entered: June 2, 2017
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`UNITED STATES PATENT AND TRADEMARK OFFICE
`____________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
`
`INTEL CORPORATION
`and
`QUALCOMM INCORPORATED, GLOBALFOUNDRIES INC.,
`GLOBALFOUNDRIES U.S. INC., GLOBALFOUNDRIES DRESDEN
`MODULE ONE LLC & CO. KG, GLOBALFOUNDRIES DRESDEN
`MODULE TWO LLC & CO. KG,
`Petitioner,
`
`v.
`
`DSS TECHNOLOGY MANAGEMENT, INC.,
`Patent Owner.
`____________
`
`Case IPR2016-002871
`Patent 6,784,552 B2
`
`
`
`Before BRYAN F. MOORE, BRIAN J. McNAMARA, and
`MINN CHUNG, Administrative Patent Judges.
`
`CHUNG, Administrative Patent Judge.
`
`
`
`FINAL WRITTEN DECISION
`35 U.S.C. § 318(a) and 37 C.F.R. § 42.73
`
`
`
`
`1 Case IPR2016-01311 has been joined with this proceeding.
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`IPR2016-00287
`Patent 6,784,552 B2
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`I. INTRODUCTION
`
`In this inter partes review, instituted pursuant to 35 U.S.C. § 314,
`Intel Corporation, Qualcomm Incorporated, Globalfoundries Inc.,
`Globalfoundries U.S. Inc., Globalfoundries Dresden Module One LLC &
`Co. KG, and Globalfoundries Dresden Module Two LLC & Co. KG
`(collectively, “Petitioner”) challenge the patentability of claims 1–7 (the
`“challenged claims”) of U.S. Patent No. 6,784,552 B2 (Ex. 1001, “the ’552
`patent”), owned by DSS Technology Management, Inc. (“Patent Owner”).
`The Board has jurisdiction under 35 U.S.C. § 6. This Final Written Decision
`is entered pursuant to 35 U.S.C. § 318(a) and 37 C.F.R. § 42.73. We base
`our decision on the preponderance of the evidence. 35 U.S.C. § 316(e); 37
`C.F.R. § 42.1(d). With respect to the grounds instituted in this trial, we have
`considered the papers submitted by the parties and the evidence cited
`therein. For the reasons discussed below, we determine Petitioner has
`shown by a preponderance of the evidence that claims 1–7 of the ’552 patent
`are unpatentable.
`
`A. Procedural History
`On December 8, 2015, Intel Corporation filed a Petition (Paper 2,
`“Pet.”) requesting inter partes review of claims 1–7 of the ’552 patent.
`Patent Owner filed a Preliminary Response (Paper 7, “Prelim. Resp.”). On
`June 8, 2016, we instituted an inter partes review of claims 1–7 of the ’552
`patent based on the following specific grounds (Paper 11, “Dec. on Inst.,”
`28–29).
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`Claim(s) Challenged
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`Statutory Basis
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`Reference(s)
`
`1, 2, and 4–7
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`3
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`§ 102(b)
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`§ 103(a)
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`Heath2
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`Heath, Hawley,3 and Chappell4
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`After institution, Qualcomm Incorporated, Globalfoundries Inc.,
`Globalfoundries U.S. Inc., Globalfoundries Dresden Module One LLC &
`Co. KG, and Globalfoundries Dresden Module Two LLC & Co. KG
`(collectively, “Qualcomm”) filed a petition requesting inter partes review of
`claims 1–7 of the ’552 patent on the same grounds asserted by Intel
`Corporation, accompanied by a timely motion seeking joinder with this
`proceeding. IPR2016-01311, Papers 3 (petition), 4 (motion for joinder).5
`Patent Owner did not oppose the joinder. We instituted an inter partes
`review and joined it with the present proceeding. Papers 18, 19.
`On September 7, 2016, Patent Owner filed a Patent Owner Response
`(Paper 20, “PO Resp.”) that contained no citations to evidence and no
`argument, other than noting that, in contrast to the standard applied in
`reaching a decision to institute (i.e., a reasonable likelihood Petitioner will
`prevail on its challenge to patentability of a claim), the standard for reaching
`
`
`2 Ex. 1003, U.S. Patent No. 4,686,000 (Aug. 11, 1987) (“Heath”).
`3 Ex. 1004, European Patent Application Publication No. 0592078 A1 (Apr.
`13, 1994) (“Hawley”).
`4 Ex. 1005, U.S. Patent No. 5,541,427 (July 30, 1996) (“Chappell”).
`5 Because Qualcomm’s petition in IPR2016-01311 is identical in all
`substantive aspects to the Petition in this proceeding (see Paper 18, 8–9), we
`cite only to the Petition throughout this Final Written Decision.
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`a final decision is whether the Petitioner proved unpatentability by a
`preponderance of the evidence. PO Resp. 2. Patent Owner then stated that it
`“defers to the Board to make this determination based on its impartial
`analysis of the prior art and Petitioners’ arguments.” Id.
`In its Reply (Paper 21, “Pet. Reply”) filed on December 7, 2016,
`Petitioner stated that Patent Owner has not cross-examined Petitioner’s
`expert, John C. Bravman, Ph.D., or provided any testimony that contradicts
`Dr. Bravman’s testimony, and that the challenged claims should be found
`unpatentable. Pet. Reply 1–2.
`No hearing was held because we determined oral argument is not
`necessary to render a final written decision in this proceeding. See Paper 24,
`2.
`
`B. Related Proceedings
`According to the parties, the ’552 patent is the subject of the
`following patent infringement cases: DSS Tech. Mgmt., Inc. v. Intel Corp.,
`Case No. 6:15-cv-130-JRG (E.D. Tex.); DSS Tech. Mgmt., Inc. v. Samsung
`Elec. Co., Ltd., Case No. 6:15-cv-690 (E.D. Tex.); DSS Tech. Mgmt., Inc. v.
`SK Hynix, Inc., Case No. 6:15-cv-691 (E.D. Tex.); and DSS Tech. Mgmt.,
`Inc. v. Qualcomm, Inc., Case No. 6:15-cv-692 (E.D. Tex.). Pet. 7; Paper 6,
`2–3. In related proceedings before the Board, we instituted inter partes
`reviews of claims 8–12 of the ’552 patent in IPR2016-00288 and IPR2016-
`01314.6 The ’552 patent is also the subject of an instituted trial proceeding
`Samsung Elec. Co., Ltd. v. DSS Tech. Mgmt., Inc., Case IPR2016-00782.
`
`
`6 Case IPR2016-01314 has been joined with IPR2016-00288.
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`Additionally, we instituted inter partes reviews of claims of U.S. Patent No.
`5,965,924 in Intel Corp. v. DSS Tech. Mgmt., Inc., Cases IPR2016-00289,
`IPR2016-00290, IPR2016-01312, and IPR2016-01313.7
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`II. THE ’552 PATENT
`A. Described Invention
`The ’552 patent describes a process of semiconductor device
`fabrication and a structure of a semiconductor device having “substantially
`rectangular” lateral insulating spacers adjacent to gate electrodes. Ex. 1001,
`Abstract. The ’552 patent defines the term “substantially rectangular” to
`mean that “a side of the spacer has an angle relative to the substrate surface
`of more than 85°.” Id. at col. 8, ll. 40–42.
`Figure 4(D) of the ’552 patent is reproduced below.
`
`
`Figure 4(D) illustrates a cross-sectional view of a series of gates 415 (also
`called conducting layers or polysilicon layers) completely encapsulated in
`insulating material 420, e.g., TEOS (tetraethyl orthosilicate glass), where
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`7 Cases IPR2016-01312 and IPR2016-01313 have been joined with
`IPR2016-00290 and IPR2016-00289, respectively.
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`spacers or spacer portions 435 of the insulating material adjacent to the gates
`have substantially rectangular profiles. Id. at col. 9, ll. 9–13; col. 11, ll. 40–
`46. As shown in Figure 4(D), gates 415 are insulated from sources or drains
`405 by insulating dielectric layers 410. See id. at col. 10, ll. 49–50. The
`’552 patent describes a process of making high quality contacts to the
`sources or drains, such as “self-aligned” contacts, by etching structures over
`substrate 400 and sources or drains 405. Id. at col. 7, ll. 19–22; col. 8, ll. 4–
`6.
`
`Figure 4(I) of the ’552 patent is reproduced below.
`
`
`Figure 4(I) illustrates additional structures deposited and etched over the
`structure described in Figure 4(D), such as second dielectric layer 440
`(called etch stop layer), blanket layer 450, and photoresist mask layer 455.
`Id. at col. 9, ll. 33–39; col. 11, ll. 63–65; col. 12, ll. 34–42. According to the
`’552 patent, etch stop layer 440, e.g., silicon nitride layer 440, depicted in
`Figure 4(I) is distinct or different from the underlying TEOS insulating
`layer. Id. at col. 12, ll. 10–11. The etch stop layer protects the underlying
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`TEOS layer when blanket layer 450 made of BPTEOS8 is etched away to
`create contact openings 460 and 465 above source or drain 445. See id. at
`col. 12, ll. 36–42; col. 4, ll. 41–59.
`A second etch is then performed to remove etch stop layer 440
`covering source or drain 445 in contact openings 460 and 465. Id. at col. 12,
`ll. 48–52; col. 7, ll. 43–45. The ’552 patent describes that the second etch is
`“almost completely anisotropic,” which means that the etchant etches in the
`vertical direction, or perpendicular relative to the substrate surface. Id. at
`col. 7, ll. 45–48; col. 12, ll. 55–58. Hence, the etch removes the etch stop
`material covering the area of the contact openings or contact regions 460 and
`465, but does not significantly etch the etch stop material adjacent to the
`spacer portions 435.9 Id. at col. 7, ll. 53–55; col. 12, ll. 58–61.
`
`
`8 BPTEOS is an acronym for borophosphosilicate tetraethyl orthosilicate
`glass. See Ex. 1001, col. 11, ll. 6–7.
`9 As discussed above, spacer portions 435 are illustrated in Figure 4(D) and
`the accompanying text. See Ex. 1001, col. 11, ll. 40–46, Fig. 4(D).
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`Figures 4(J) and 4(K) of the ’552 patent are reproduced below.
`
`
`Figures 4(J) and 4(K) illustrate the structure of the semiconductor device of
`the ’552 patent after the second etch for removing the etch stop layer from
`the contact regions 460 and 465 is completed. As shown in Figures 4(J) and
`4(K), due to the anisotropic or vertical nature of the second etch, only a
`small portion, i.e., portion 475, of the TEOS spacer portion 435 is removed
`during the etch. Id. at col. 13, ll. 6–9. Of primary significance, according to
`the ’552 patent, the spacer portion 435 of the TEOS insulating layer 420
`retains its substantially rectangular profile, in contrast to the conventional
`prior art method which transforms a substantially rectangular spacer into a
`sloped spacer. Id. at col. 13, ll. 9–10; col. 7, ll. 48–51; col. 5, ll. 4–14.
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`B. Illustrative Claim
`Claim 1 is illustrative of the challenged claims and is reproduced
`below with the key limitation (the “angle limitation”) emphasized in italics:
`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
`(e) 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°.
`
`III. CLAIM CONSTRUCTION
`As acknowledged by the parties, the ’552 patent has expired. Pet. 29;
`Prelim. Resp. 15. Thus, we construe the claims in accordance with the
`standard set forth in Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005)
`(en banc). See In re CSB-Sys. Int’l, Inc., 832 F.3d 1335, 1341 (Fed. Cir.
`2016) (“[W]hen an expired patent is subject to reexamination, the traditional
`Phillips construction standard attaches.”) (citing In re Rambus, 694 F.3d 42,
`46 (Fed. Cir. 2012)); Black & Decker, Inc. v. Positec USA, Inc., 646 Fed.
`App’x 1019, 1024 (Fed. Cir. 2016) (holding that in an inter partes review,
`“[c]laims of an expired patent are given their ordinary and customary
`meaning in accordance with our opinion in [Phillips]”).
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`In the Decision on Institution, applying the Phillips standard, we
`preliminarily interpreted the “angle limitation” set forth above—i.e., the
`limitation reciting “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°”—to mean “a side of the insulating spacer has an angle relative to the
`substrate surface that is greater than 85° and less than or equal to 90°.” Dec.
`on Inst. 8–14. Importantly, we were unpersuaded by Patent Owner’s
`argument that the angle of a side of the insulating spacer must be obtained
`“through the use of a low selectivity etch” (Prelim. Resp. 16–20) and
`determined that the challenged claims do not require the use of a low
`selectivity etch. Dec. on Inst. 9–12.
`The parties do not present additional claim construction arguments in
`their Patent Owner Response and Petitioner Reply. Upon considering the
`complete record, we discern no reason to deviate from our construction,
`which was adopted from the parties’ agreed construction at the district court
`(Dec. on Inst. at 13–14 (citing Ex. 1028 (Dist. Ct. Claim Construction
`Order), 7–8)), and maintain our construction of the “angle limitation” to
`mean “a side of the insulating spacer has an angle relative to the substrate
`surface that is greater than 85° and less than or equal to 90°.”
`No other claim terms need to be construed expressly for purposes of
`this Final Written Decision. See Wellman, Inc. v. Eastman Chem. Co., 642
`F.3d 1355, 1361 (Fed. Cir. 2011) (explaining that “claim terms need only be
`construed ‘to the extent necessary to resolve the controversy’” (quoting
`Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir.
`1999))).
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`IV. ANALYSIS OF PETITIONER’S PRIOR ART CHALLENGES
`As previously discussed, the Patent Owner Response does not contain
`any substantive argument or citations to evidence. Although it remains
`Petitioner’s burden to prove unpatentability by a preponderance of the
`evidence, in our Scheduling Order, we cautioned Patent Owner that “any
`arguments for patentability not raised in the response will be deemed
`waived.” See Paper 12, 4–5. Patent Owner elected not to respond
`substantively and, instead, “defers to the Board” to determine whether
`Petitioner has demonstrated the challenged claims are unpatentable by a
`preponderance of the evidence. PO Resp. 2. Under the particular
`circumstance of this case, for purposes of this Final Written Decision, we
`exercise our discretion to consider Patent Owner’s substantive patentability
`arguments in its Preliminary Response in reaching a decision as set forth
`below. See 37 C.F.R. § 42.5(a).
`A. Anticipation by Heath
`Petitioner asserts that claims 1, 2, and 4–7 are unpatentable under
`35 U.S.C. § 102(b) as anticipated by Heath. Pet. 36–46. Petitioner provides
`detailed explanations and specific citations to Heath indicating where in the
`reference the claimed features are disclosed. Id. In addition, Petitioner
`relies upon the Declaration of John C. Bravman, Ph.D. (“Bravman Decl.,”
`Ex. 1002) to support its position. Id. Upon review of all of the parties’
`papers and supporting evidence discussed in those papers, we are persuaded
`that Petitioner has demonstrated, by a preponderance of evidence, that
`claims 1, 2, and 4–7 are unpatentable under 35 U.S.C. § 102(b) as
`anticipated by Heath.
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`1. Principles of Law
`A claim is unpatentable under 35 U.S.C. § 102 only if a single prior
`art reference expressly or inherently describes each and every limitation set
`forth in the claim. See Perricone v. Medicis Pharm. Corp., 432 F.3d 1368,
`1375 (Fed. Cir. 2005); Verdegaal Bros., Inc. v. Union Oil Co., 814 F.2d 628,
`631 (Fed. Cir. 1987). Further, a reference cannot anticipate “unless [it]
`discloses within the four corners of the document not only all of the
`limitations claimed[,] but also all of the limitations arranged or combined in
`the same way as recited in the claim.” Net MoneyIN, Inc. v. VeriSign, Inc.,
`545 F.3d 1359, 1371 (Fed. Cir. 2008). Although the elements must be
`arranged in the same way as in the claim, “the reference need not satisfy an
`ipsissimis verbis test,” i.e., identity of terminology is not required. In re
`Gleave, 560 F.3d 1331, 1334 (Fed. Cir. 2009); In re Bond, 910 F.2d 831,
`832 (Fed. Cir. 1990). We analyze this asserted ground based on anticipation
`with the principles identified above in mind.
`
`2. Overview of Heath
`Heath describes a process for forming a self-aligned contact window
`in a semiconductor device, such as an integrated circuit. Ex. 1003, Abstract.
`Heath describes a two-step etching process which comprises the steps of first
`etching a dielectric layer down to a silicon nitride etch stop layer, and then
`etching the etch stop, leaving a “stick” of the etch stop material on the
`vertical sidewall of the layer to be protected. Id.
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`Figure 8B of Heath is reproduced below.
`
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`Figure 8B depicts a cross-sectional view of a semiconductor structure after
`the first etching step, including gate electrode 16 insulated from contact
`window 32 and source or drain 20 by silicon nitride layer 10. See id. at
`col. 9, ll. 50–67. In the second etching step, etch stop layer 10 is removed to
`open contact window 32 to source or drain 20. Heath describes that, because
`the nitride removal is anisotropic, vertical “stick” 10a of nitride layer 10 will
`remain on the side of gate electrode 16 so that no electrical short occurs
`between the gate electrode and the contact window or the source or drain
`region. Id. at col. 10, ll. 1–11.
`
`3. Discussion
`
`a. Claim 1
`Petitioner asserts that the embodiment depicted in Figure 8C of Heath
`discloses every limitation of claim 1. Pet. 36. According to Petitioner,
`Heath is directed to the same problem as the ’552 patent—i.e., avoiding a
`short-circuit between the contact and the gate electrode—and describes
`solving the problem in the same way—that is, through the use of a non-
`conductive sidewall spacer with vertical sides. Id. at 25 (citing Ex. 1003,
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`Abstract; Ex. 1002 ¶ 60). Petitioner references Figure 8C of Heath and
`asserts that Heath discloses a transistor structure consisting of the same
`components arranged in the same way as the invention of the ’552 patent.
`Id. at 25–26 (identifying various components depicted in Fig. 8C and citing
`Ex. 1003, Abstract, Fig. 8C, col. 5, ll. 26–30, col. 10, ll. 2–13; Ex. 1002
`¶¶ 61, 62).
`Figure 8C of Heath is reproduced below.
`
`
`Figure 8C above depicts a cross-sectional view of a semiconductor structure
`at the same stage of processing as Figure 8B (reproduced in Overview of
`Heath section above) combined with the addition of a sidewall spacer 16a.
`Ex. 1003, col. 10, ll. 14–19. Referencing Figure 8C, Petitioner provides
`detailed explanations and specific citations to Heath indicating where in the
`reference each limitation of claim 1 is disclosed. Pet. 36–43. For the
`reasons discussed below, we are persuaded that Heath discloses each
`limitation of independent claim 1 as arranged in the claim.
`
`i. Preamble and Elements (a), (b), (c), (d), and (e)
`Beginning with the preamble of claim 1, Petitioner cites Heath’s
`disclosure of a transistor structure in Figure 8C as disclosing a “structure”
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`recited in claim 1. Id. at 36 (citing Ex. 1003, col. 10, ll. 33–35, Fig. 8C;
`Ex. 1002 ¶ 85). We agree with Petitioner that Figure 8C of Heath discloses
`a “structure” recited in claim 1 because, as noted by Petitioner, Heath
`describes methods to “produce a transistor structure which has source/drain
`implants like those shown in FIG. 8C.” Id. (quoting Ex. 1003, col. 10,
`ll. 33–35); see also id. at 25–26 (Petitioner arguing that Figure 8C of Heath
`discloses a transistor structure consisting of the same components arranged
`in the same way as the invention of the ’552 patent). As discussed above,
`both the ’552 patent and Heath describe a process of forming a self-aligned
`contact structure in a semiconductor device. Ex. 1001, Abstract, col. 7,
`ll. 19–22, col. 8, ll. 4–6 (“The structure contemplated by the invention is an
`effective device for small feature size structures, particularly self-aligned
`contacts.”); Ex. 1003, Abstract.
`Petitioner next addresses the limitations recited in the body of claim 1.
`Claim 1 numbers from (a) to (e) the elements recited in the body of the claim
`and recites the numbered elements as follows: (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 (e) 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.
`Petitioner asserts that gate electrode 16 depicted in Figure 8C
`discloses “(a) a conductive layer disposed over a substrate,” as recited in
`claim 1. Id. at 36–37 (citing Ex. 1003, col. 8, ll. 8–11; col. 9, ll. 44–47, 50–
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`55; col. 7, ll. 36–38; Figs. 2–7, 8C). Petitioner notes that Heath discloses
`gate electrode 16 is made of polysilicon, which Petitioner argues citing the
`testimony of Dr. Bravman, a person of ordinary skill in the art would
`understand to be electrically conductive in a transistor structure. Id. at 37
`(citing Ex. 1003, col. 8, ll. 8–11; Ex. 1002 ¶ 86). Petitioner further argues
`that Figure 2 of Heath shows gate electrodes 14 and 16 are formed over
`substrate 12 as part of the same process of forming the structure depicted in
`Figure 8C. Id. (citing Ex. 1003, col. 7, ll. 36–38, Fig. 2).
`We credit Dr. Bravman’s testimony and are persuaded that polysilicon
`used to form gate electrode 16 of Heath is an electrically conductive
`material. We are also persuaded that Figure 2 of Heath showing gate
`electrode 16 formed over substrate 12 is part of the same process of forming
`the structure depicted in Figure 8C because both figures illustrate the process
`of forming a self-aligned contact window in a semiconductor device. See
`Ex. 1003, col. 2, ll. 28–32 (“FIG. 2 shows an illustrative semiconductor
`structure near the completion of processing according to the invented
`process applied illustratively for establishing a self-aligned contact window
`to a gate electrode or field-shield electrode edge.” (emphasis added)),
`col. 11, ll. 11–13 (“As a result of the process described with reference to
`FIGS. 8 and 9, the contact window to the active area will be self-aligned,
`i.e., it will be protected from shorting to an element nearby to which contact
`is not to be made.” (emphases added)). Therefore, we are persuaded by
`Petitioner’s argument and evidence that Heath discloses “(a) a conductive
`layer disposed over a substrate,” as recited in claim 1.
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`Petitioner next asserts that oxide layer 24b depicted in Figure 8C
`discloses “(b) a first insulating layer on the conductive layer” recited in
`claim 1. Pet. 37–38 (citing Ex. 1003, col. 9, ll. 52–55, Fig. 8C). Petitioner
`relies upon the testimony of Dr. Bravman and argues oxide is a common
`insulating material known to persons of ordinary skill in the art to be an
`insulating layer in a transistor structure. Id. at 38 (citing Ex. 1002 ¶ 87).
`As noted by Petitioner, Figure 8C plainly shows that oxide layer 24b
`is formed on gate electrode 16. Id. 37–38 (identifying oxide layer 24b
`formed on gate electrode 16 in Petitioner-annotated Fig. 8C (not reproduced
`herein)). We note that Heath describes oxide as an insulating material.
`Ex. 1003, col. 5, ll. 27–31 (“a self-aligned contact process which involves
`establishing gate electrodes . . . protecting the tops of these elements with an
`insulating oxide” (emphasis added)), col. 14, ll. 31–32 (“Oxide 87a . . . is
`grown as an insulator” (emphases added)). On the complete record, we
`credit the testimony of Dr. Bravman and are persuaded that oxide layer 24b
`on top of gate electrode 16 depicted in Figure 8C discloses “(b) a first
`insulating layer on the conductive layer,” as recited in claim 1.
`Figure 8C of Heath, as annotated by Petitioner, is reproduced below.
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`Pet. 40. Annotated Figure 8C above shows Petitioner’s identification of
`several limitations of claim 1 present in Heath.
`Petitioner asserts that contact window 32 (annotated in pink above) in
`oxide layer 24b (annotated in gray) shown in Figure 8C discloses “(c) a
`contact region in said first insulating layer” recited in claim 1. Id. at 38–39
`(citing Ex. 1003, col. 10, ll. 57–61; Fig. 8C). Citing the testimony of Dr.
`Bravman, Petitioner argues that contact window 32 (i.e., the claimed
`“contact region”) is created by removing material in insulating layers 24a
`and 24b (as well as portions of etch stop layer 10 and spacer 16a) in the area
`colored in pink in Annotated Figure 8C above. Id. (citing Ex. 1002 ¶ 88).
`Petitioner argues that the ’552 patent similarly describes the process of
`forming a contact region in the insulating layer above the gate by etching an
`opening through the insulating layer. Id. at 39 n.8 (citing Ex. 1001, col. 11,
`ll. 14–17, Fig. 4(B); Ex. 1002 ¶ 88 n.6). Petitioner further argues that
`contact window 32 forms an opening for electric contact that extends down
`to source/drain 20. Id. at 38 (citing Ex. 1003, col. 10, ll. 57–61; Fig. 8C).
`We are persuaded by Petitioner’s argument because Figure 8C shows
`contact window 32 has been formed by creating an opening in oxide layers
`24a and 24b, as indicated by the dotted lines 56 outlining the removed
`portions. Petitioner’s argument is consistent with the disclosure in Heath’s
`Figures 8A, 8B, 8C and their accompanying text, which describe in detail
`the process of forming contact window 32 by etching away materials in
`oxide layers 24a and 24b (as well as portions of etch stop layer 10 and oxide
`spacer 16a) along the dotted lines 56 and creating an opening that extends
`down to source/drain 20. Ex. 1003, Figs. 8A–C, col. 6, l. 67–col. 7, l. 3,
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`col. 9, l. 50–col. 11, l. 15. Petitioner’s cited evidence is part of this
`disclosure. Based on the complete record, we are persuaded that Heath
`discloses “(c) a contact region in said first insulating layer,” as recited in
`claim 1.
`Petitioner asserts that Figure 8C of Heath also discloses “(d) at least
`one insulating spacer in the contact region adjacent to the first insulating
`layer,” as recited in claim 1. Pet. 39–40 (citing Ex. 1003, col. 10, ll. 12–27,
`Fig. 8C). Petitioner identifies sidewall spacer 16a shown in Figure 8C
`(colored in brown in Annotated Figure 8C reproduced above) as the claimed
`“insulating spacer,” and argues that sidewall spacer 16a is in contact window
`32, i.e., the claimed “contact region,” and adjacent to oxide layer 24b, the
`claimed “first insulating layer.” Id. at 39. Citing the testimony of Dr.
`Bravman, Petitioner argues that sidewall spacer 16a is an insulating spacer
`because it is made of insulating oxide. Id. at 39–40 (citing Ex. 1003, col. 10,
`ll. 23–25; Ex. 1002 ¶ 89).
`We are persuaded by Petitioner’s argument that sidewall spacer 16a is
`“in” contact window 32 because Figure 8C shows, as indicated by dotted
`line 56, a portion of sidewall spacer 16a has been removed to create an
`opening and form contact window 32. We are also persuaded that oxide
`spacer 16a is an insulating spacer because, as discussed above, oxide is a
`common insulating material known to persons of ordinary skill in the art.
`Therefore, we are persuaded that Heath discloses “(d) at least one insulating
`spacer in the contact region adjacent to the first insulating layer,” as recited
`in claim 1.
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`Referencing Annotated Figure 8C reproduced above, Petitioner next
`asserts that Heath discloses “(e) 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,” as recited in claim 1.
`Pet. 40–41 (citing Ex. 1003, Abstract, col. 5, ll. 38–39, col. 9, ll. 2–4, 66–67,
`col. 10, ll. 12–27, Fig. 8C). Petitioner identifies etch stop layer 10 shown in
`Figure 8C (annotated in purple in Annotated Figure 8C above) as the
`claimed “etch stop material” and argues that, as shown in Figure 8C, etch
`stop layer 10 is over oxide layer 24b (i.e., the claimed “first insulating
`layer”) and adjacent to sidewall spacer 16a (i.e., the claimed “insulating
`spacer”). Id. at 40. Citing the testimony of Dr. Bravman, Petitioner asserts
`that etch stop layer 10 is a “different material” from sidewall spacer 16a
`because etch stop layer 10 made of silicon nitride whereas sidewall spacer
`16a is formed of oxide. Id. (citing Ex. 1003, Abstract, col. 5, ll. 38–39,
`col. 9, ll. 2–4, 66–67, col. 10, ll. 12–27; Ex. 1002 ¶ 90). Petitioner further
`argues that, in both the ’552 patent and Heath, a vertical “stick” of etch stop
`material remains adjacent to the sidewall spacer in the contact opening after
`the etching process forms the contact opening. Id. at 40–41 (citing Ex. 1001,
`col. 12, ll. 58–65; Ex. 1003, col. 10, ll. 1–11; Ex. 1002 ¶ 91).
`We are persuaded by Petitioner’s argument because Figure 8C plainly
`shows etch stop layer 10 is over oxide layer 24b and adjacent to sidewall
`spacer 16a on the right side of oxide layer 24b. As noted by Petitioner,
`sidewall spacer 16a is also adjacent to “vertical ‘stick’ 10a of layer 10” on
`the left side of oxide layer 24b, as illustrated in Figure 8C. Id. (quoting
`Ex. 1003, col. 10, ll. 1–11). In addition, we credit Dr. Bravman’s testimony
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`and are persuaded that silicon nitride which comprises etch stop layer 10 is a
`different material from oxide that makes up sidewall spacer 16a. Therefore,
`we are persuaded that Heath discloses “(e) 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,” as recited in
`claim 1.
`Patent Owner does not dispute specifically Petitioner’s contention that
`Heath discloses the preamble and numbered elements (a), (b), (c), (d), and
`(e) of claim 1. Upon considering the complete record, we determine
`Petitioner has demonstrated that Heath discloses the preamble and elements
`(a), (b), (c), (d), and (e) of claim 1.
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`ii. The “Angle Limitation”
`The last limitation of claim 1, the “angle limitation,” recites “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°.” Petitioner
`asserts that Figure 8C of Heath also discloses the “angle limitation” recited
`in claim 1. Pet. 41–43. According to Petitioner, Heath discloses a sidewall
`spacer 16a with a side that is at a right angle relative to the substrate surface
`because Heath describes the sidewall spacers as “vertical” with respect to the
`substrate. Id. at 41–42 (citing Ex. 1003, Abstract; col. 11, ll. 1–10; Fig. 8C).
`Pointing to Figure 8C of Heath, Petitioner argues Heath describes that the
`entire side of the sidewall spacer is at a 90° angle relative to the substrate
`surface, and, therefore, the sidewall spacer meets the “angle limitation”
`regardless of where along the side of the sidewall spacer—be it near the
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`bottom or near the top of the spacer—the angle is measured relative to the
`substrate surface. Id. at 42–43.
`Patent Owner asserts that Heath does not disclose the “angle
`limitation” recited in claim 1 because Heath does not describe using a low
`selectivity etch to obtain substantially rectangular insulating spacers.
`Prelim. Resp. 26–27. Patent Owner further asserts that Heath is merely
`cumulative of the prior art structure disclosed in the Background of the
`Invention section of the ’552 patent and that the vertical sidewall in Figure
`8C of Heath relied upon by Petitioner is the same as the prior art “vertical
`sidewall” that is shown in Figure 1(B) of the ’552 patent. Id. at 27–28.
`Patent Owner contends that both figures do not show actual