Case: 17-2474
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`Document:68
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`Page:1_
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`Filed: 06/12/2019
`
`Gnited States Court of Appeals
`for the Federal Circuit
`
`SAMSUNG ELECTRONICSCO., LTD., MICRON
`TECHNOLOGY,INC., SK HYNIX INC.,
`Appellants
`
`Vv.
`
`ELM 3DS INNOVATIONS, LLC,
`Appellee
`
`2017-2474, 2017-2475, 2017-2476, 2017-2478, 2017-2479,
`2017-2480, 2017-2482, 2017-2483, 2018-1050, 2018-1079,
`2018-1080, 2018-1081, 2018-1082
`
`Appeals from the United States Patent and Trademark
`Office, Patent Trial and Appeal Board in Nos. JPR2016-
`00386, IPR2016-00387, IPR2016-00388, IPR2016-00390,
`IPR2016-00391,
`IPR2016-00393,
`IPR2016-00394,
`IPR2016-00395,
`IPR2016-00687,
`IPR2016-00691,
`IPR2016-00708, IPR2016-00770, IPR2016-00786.
`
`Decided: June 12, 2019
`
`RUFFIN B. CORDELL, Fish & Richardson PC, Washing-
`ton, DC, argued for all appellants. Appellants Micron
`Technology,
`Inc., SK Hynix Inc. also represented by
`CHRISTOPHER DRYER, TIMOTHY W. RIFFE, ROBERT ANDREW
`SCHWENTKER, ADAM SHARTZER; CRAIG E. COUNTRYMAN,
`RYAN LYNN FREI, OLIVER RICHARDS, San Diego, CA.
`
`

`

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`2
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`SAMSUNGELECTRONICSCO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
`
`NAVEEN MODI, Paul Hastings LLP, Washington, DC,
`for appellant Samsung Electronics Co., Ltd. Also repre-
`sented by PHILLIP W. CITROEN, ALLAN SOOBERT.
`
`WILLIAM MEUNIER, Mintz, Levin, Cohn, Ferris, Glovsky
`and Popeo, P.C., Boston, MA, argued for appellee. Also rep-
`resented by KEVIN AMENDT, SANDRA BADIN, MATTHEW
`STEPHEN GALICA, MICHAEL NEWMAN, MICHAEL TIMOTHY
`RENAUD, JAMES M. WODARSKI.
`
`Before MOORE, REYNA, and CHEN, Circuit Judges.
`
`MOORE, Circuit Judge.
`
`Samsung Electronics Co., Ltd., Micron Technology,
`Inc., and SK Hynix Inc. (collectively, “Petitioners”) appeal
`from the final written decisions of the Patent Trial and Ap-
`peal Board in thirteen inter partes reviews holding that
`they did not establish the unpatentability of 105 claims
`across eleven patents (“Challenged Patents”). Given that
`each challenged claim requires a low-tensile-stress dielec-
`tric, and substantial evidence supports the Board’s finding
`that a person of ordinary skill in the art would not have
`reasonably expected success in combining theprior art to
`meetthis limitation, we affirm.
`
`

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`SAMSUNG ELECTRONICSCO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
`
`3
`
`BACKGROUND
`
`Appellee Elm 3DS Innovations LLC (“Elm”) is the
`ownerof the Challenged Patents, which share a specifica-
`tion and all relate to “stacked integrated circuit memory.”
`672 patent at 1:7-8. The Challenged Patents are the sub-
`ject of co-pending litigation between Elm andPetitioners.
`
`The Boardinstituted inter partes review based on thir-
`teen petitionsfiled by Petitioners. Amongothersnotatis-
`sue on appeal,
`the petitions challenged the following
`claims: claims 17-18, 22, 84, 95, 129-32, 145-46, and 152
`of the 672 patent (TPR2016-00386); claims 1-2, 8, 14, 31—
`32, 44, 46, and 52—54 of the ’778 patent (IPR2016-00387);
`claims 10-12, 18-20, 60-63, 67, 70—73, and 77 of the ’239
`patent (PR2016-00388 and IPR2016-00393); claims 1-3,
`30-31, 33, 40-41, and 44 of the ’542 patent (PR2016-
`00390); claims 30, 34, 36, 135-138, and 147 of the ’862 pa-
`tent IPR2016-00391); claims 36 and 51 of the ’617 patent
`(PR2016-00394); claims 1, 10-11, and 13-14 of the ’732
`patent IPR2016-00395); claims 1, 7, 17-18, and 33 of the
`119 patent (PR2016-00687); claims 1 and 20—23 of the
`004 patent (PR2016-00691); claims 1, 12-13, 24, 36-38,
`53, 83, 86-87, and 132 of the 499 patent TPR2016-00708
`and IPR2016-00770); and claims 58, 60-61, and 67 of the
`570 patent (IPR2016-00786). Each ground challenging the
`claims was based on obviousness andasserted either U.S.
`Patent No. 5,202,754 (“Bertin”) or a 1996 article by Kee-Ho
`Yu, et. al.,
`titled “Real-Time Microvision System with
`Three-Dimensional Integration Structure” (“Yu”) as the
`
`issue are U.S. Patent Nos.
`The patents at
`1
`8,653,672; 8,841,778; 7,193,239; 8,629,542; 8,796,862;
`8,410,617; 7,504,732; 8,928,119; 7,474,004; 8,907,499; and
`8,933,570.
`2
`For simplicity, this opinion cites only to the specifi-
`cation of the ’672 patent.
`
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`° SAMSUNG ELECTRONICS CO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
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`primary reference in combination with, relevant here, U.S.
`Patent No. 5,354,695 (““Leedy”).
`
`The Board held that Petitioners had not mettheir bur-
`den of demonstrating that the claims were unpatentable.
`Specifically, it found that the prior art did not disclose the
`“substantially flexible” limitation. It also found that Peti-
`tioners did not demonstrate a motivation to combine Bertin
`or Yu with Leedy or a reasonable expectation of success in
`doing so. Petitioners timely filed notices of appeal, and the
`appeals were consolidated. We havejurisdiction pursuant
`to 28 U.S.C. § 1295(a)(4)(A).
`
`DISCUSSION
`
`I. Claim Construction
`
`“We review the Board’s constructions based on intrin-
`sic evidence de novo andits factual findings based on ex-
`trinsic evidence for substantial evidence.” HTC Corp. v.
`Cellular Comme’ns Equip., LLC, 877 F.3d 1361, 1367 (Fed.
`Cir. 2017). The Board construes claims in an unexpired
`patent according to their broadest reasonable interpreta-
`tion in light of the specification.
`37 C.F.R. § 42.100(b)
`(2017).4 Claimsof an expired patent are construed accord-
`ing to the standard applied by district courts. See In re
`CSB-Sys. Intl, Inc., 832 F.3d 1335, 13841 (Fed. Cir. 2016)
`(referencing Phillips v. AWH Corp., 415 F.3d 1303 (Fed.
`
`Claim 1 of the ’499 patent was challenged based on
`3
`U.S. Patent No. 5,731,945, which contains the same disclo-
`sure as Bertin and addsdetails not relevant to this appeal.
`4
`The Board’s decisions issued prior to the effective
`date of the U.S. Patent and Trademark Office’s change to
`the claim construction standard applied in interpartes re-
`view. See Changes to the Claim Construction Standardfor
`Interpreting Claims in Trial Proceedings Before the Patent
`Trial and Appeal Board, 83 Fed. Reg. 51,340 (Oct. 11,
`2018).
`
`

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`SAMSUNGELECTRONICS CO., LTD. v. ELM 3DS INNOVATIONS,
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`Cir. 2005) (en banc)). While some patents were expired at
`the time of the Board’s final written decision and others
`were not, the parties agree that the different claim con-
`struction standards do not impact the outcome. Appel-
`lants’ Br. 44; Appellee’s Br. 41. The parties have not
`contested the Board’s application of the Phillips claim con-
`struction standard.
`
`All challenged claims except for claims 1 and 14 of the
`°778 patentuse “substantially flexible” in at least one of two
`ways. Thefirst is to modify the term “semiconductor sub-
`strate.” Claim 129 of the ’672 patent illustrates the use in
`this context (emphasis added):
`
`An integrated circuit structure comprising:
`
`a first substrate comprising a first surface
`supporting interconnect contacts;
`
`a substantially flexible semiconductor sec-
`ond substrate comprising a first surface
`and a second surface at least one of which
`supports interconnect contacts, wherein
`the second surfaceis opposite the first sur-
`face and wherein the second surface of the
`second substrate is formed by removal of
`semiconductor material from the second
`substrate and is smoothedorpolished after
`removal of the semiconductor material; and
`
`conductive paths between the interconnect
`contacts supported by the first surface. of
`the first substrate and of the interconnect
`contacts supported by the second sub-
`strate;
`
`wherein thefirst substrate and the second
`substrate overlap fully or partially in a
`stacked relationship; and
`
`

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`SAMSUNG ELECTRONICSCO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
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`wherein the integrated circuit structure
`further comprises a low-stress_ silicon-
`based dielectric material having a stress of
`5x108 dynes/cm? tensile or less.
`
`“Substantially flexible” is also used to modify “circuit lay-
`ers,” and other similar terms.’ Claim 30 of the 862 patent
`illustrates how “substantially flexible” is used in this con-
`text (emphasis added):
`
`A stacked circuit structure comprising:
`
`a plurality of stacked, thin, substantially
`flexible circuit layers at least one of which
`comprises a thinned, substantially flexible
`monocrystalline semiconductor -substrate
`of one piece;
`
`wherein at least one of the substantially
`flexible circuit layers comprises at least one
`memory array comprising memory cells
`and a low stress silicon-based dielectric .
`material; and
`
`at least one vertical interconnection that
`passes throughat least one of the plurality
`of stacked, thin, substantially flexible cir-
`cuit layers.
`
`See, eg., 239 patent at Claim 60 (“substantially
`5
`flexible” die); 004 patent at Claim 1 (“substantially flexible
`integrated circuits”); ’732 patent at Claim 1 (“substantially
`flexible integrated circuit layer”). The parties do nottreat
`this difference in terminology as affecting the construction
`of “substantially flexible.” Accordingly, our construction of
`“substantially flexible” applies acrossall its uses.
`
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`q
`
`In each context, the Boardrelied on a general-purpose dic-
`tionary to construe “substantially flexible” to mean “largely
`able to bend without breaking.” E.g., J.A. 31.
`
`“Claim terms generally are construed in accordance
`with the ordinary and customary meaning they would have
`to one of ordinary skill in the artin light of the specification
`and the prosecution history.” Aventis Pharma S.A. v. Hos-
`pira, Inc., 675 F.3d 1324, 1329 (Fed. Cir. 2012) (citing Phil-
`lips, 415 F.3d at 1812). Extrinsic evidence may also be
`considered in construing a claim, though “it is less signifi-
`cant than the intrinsic record in determining the legally
`operative meaning of claim language.” Phillips, 415 F.3d
`at 1317 Gnternal quotation marks omitted). Wewill devi-
`ate from a claim term’s ordinary meaning “whena patentee
`sets out a definition and acts as its own lexicographer”or
`“when the patentee disavowsthe full scope of a claim term
`either in the specification or during prosecution.” Aventis,
`675 F.3d at 1330 (quoting Thorner v. Sony Computer
`Enim’t Am. L.L.C., 669 F.3d 1362, 1365 (Fed. Cir. 2012)).
`
`The parties dispute the meaning of “substantially flex-
`ible.” “Where multiple patents derive from the same par-
`ent application and share many common terms, we must
`interpret the claims consistently across all asserted pa-
`tents.” SightSound Techs., LLC v. Apple Inc., 809 F.3d
`1307, 1316 (Fed. Cir. 2015) Gnternal quotation marks omit-
`ted). The parties do not argue that the definition of “sub-
`stantially flexible” depends on the patent or claim in which
`itis used. Because the Challenged Patents derive from the
`same parent application and use “substantially flexible”
`throughout, we construe that term the same way for each
`Challenged Patent.
`
`Petitioners argue the intrinsic record supports a con-
`struction of “substantially flexible” substrate as a “sub-
`strate that has been thinned to a thickness of less than 50
`uum and subsequently polished or smoothed.” Appellants’
`
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`SAMSUNG ELECTRONICSCO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
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`Br. 36. Specifically, they rely on the specification’s disclo-
`sure of step “2A” in a fabrication sequence for a “3DS
`memory circuit,” which states: “Grind the backsideor ex-
`posed surface of the secondcircuit substrate to a thickness
`of less than 50 pm and then polish or smooth the surface.
`The thinned substrate is now a substantially flexible sub-
`strate.” 672 patent at 9:3-6; see also id. at 2:66-67, 3:5-8
`(stating that a feature of the stacked circuit assembly tech-
`nology includes “[t]hinning of the memory circuit to less
`than about50 pm in thickness forming a substantially flex-
`ible substrate”). Though these disclosuresrefer to the sub-
`strate being substantially flexible, Petitioners argue they
`apply with equalforce to the claimsreciting “substantially
`flexible” circuit layers, and similar limitations, because the
`prosecution history requires that a substantially flexible
`circuit layer includes a substantially flexible substrate.
`
`Elm responds that the Board’s construction is con-
`sistent with the ordinary meaning of “substantially flexi-
`ble” and the specification’s distinction between flexible and
`rigid substrates.
`It criticizes Petitioners’ proposed con-
`struction as departing from the ordinary meaning, since
`the flexibility of a material depends on more than how thin
`andpolished it is. Citing the declaration of Petitioners’ ex-
`pert Dr. Paul Franzon, Elm arguesthe flexibility of a sem-
`iconductor substrate depends on the substrate’s elastic
`modulus, crystal orientation, and dimensions. Appellee’s
`Br. 48—49 (citing J.A. 2191-92 4 71).
`
`Neither party’s construction is quite right. We begin
`our analysis with the claim language. The claimsindicate
`that, at least in some situations, thinning and polishing a
`substrate is one way of forming a substantially flexible sub-
`strate. For example, claim 31 of the ’778 patent recites “the
`semiconductor substrate is
`thinned and polished or
`smoothed such that the semiconductor substrate is sub-
`stantially flexible.” See also ’862 patent at Claim 147 (re-
`citing “the polished or smoothed backside [of a thinned,
`monocrystalline semiconductor substrate] enables the...
`
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`substrate to be substantially flexible, and the polished or
`smoothed backside reduces the vulnerability of the .
`.
`. sub-
`strate to fracture as a result of flexing”). But that does not
`meanthis is the only way to achieve substantialflexibility.
`The claim on which claim 31 dependsrecites “the semicon-
`ductor substrate is substantially flexible,” ’778 patent at
`Claim 2, implying that it covers substantially flexible sub-
`strates formed in ways other than the onerecited in claim
`31, Clearstream Wastewater Sys., Inc. v. Hydro-Action,
`Inc., 206 F.3d 1440, 1446 (Fed. Cir. 2000) (“Under the doc-
`trine of claim differentiation, it is presumed that different
`words used in different claims result in a difference in
`meaning and scope for each of the claims.”). Claim 51 of
`the ’617 patent recites “the bottomside of the first substrate
`is polished to make the substrate substantially flexible,”
`with nospecific “thinned” limitation. Conversely, claim 8
`of the ’778 patent lacks a polishing limitation, reciting a
`substrate that “is formed from a semiconductor wafer and
`is thinned and substantially flexible.” The claims alone do
`not supportlimiting “substantially flexible” to Petitioners’
`proposed construction.
`
`The prosecution history, on the other hand, shows that
`“substantially flexible” is narrower than the Board’s con-
`struction of “largely able to bend without breaking.”
`E.g., J.A. 31. During prosecution of the application that
`led to the ’499 patent, the examiner objected to the use of
`the term “substantially flexible” because it rendered the
`claim’s scope unclear. J.A. 10260. Elm responded that “the
`meaningof [substantially flexible] as used in the claimsis
`clearly explained in the specification,” citing to step 2A in
`the fabrication sequence. J.A. 10275. “As described in this
`passage,” Elm continued, “a semiconductor substrate is
`causedto be substantially flexible by thinning it to 50 m1-
`cronsor less and polishing or smoothing the thinned semi-
`conductor
`substrate to relieve
`stress.
`The phrase
`‘substantially flexible’ is used in the claims consistent with
`this description, which is unambiguous.” Id. To overcome
`
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`SAMSUNG ELECTRONICS CO., LTD. v. ELM 3DS INNOVATIONS,
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`the examiner’s objection, Elm clearly and unambiguously
`disclaimed claim scope. For a semiconductor substrate to
`be “substantially flexible” according to the claims, it must
`be thinned to 50 microns or less and polished or smoothed.
`
`This definition of “substantially flexible” applies to all
`its uses. In responseto a rejection of claims reciting a sub-
`stantially flexible circuit layer in an application related to
`the Challenged Patents, Elm stated that “a substantially
`flexible semiconductor substrate is a necessary but not a
`sufficient condition for a substantially flexible circuit
`layer.” J.A. 10316 (emphasis in original). Reinforcing this
`point, Elm in a response involving anotherrelated applica-
`tion explained:
`
`Two features are required to achieve substantial
`flexibility. One is that the semiconductor material
`must be sufficiently thin, e.g., 50 microns or
`less.... The other is that the dielectric material
`used in processing the semiconductor material
`must be sufficiently low stress. Otherwise, sub-
`stantial flexibility is defeated. As set forth in the
`present specification, stress of 5 x 108 dynes/cm?2or
`less has been demonstratedto satisfy this require-
`ment.
`
`J.A. 16038 (emphasis added). See also J.A. 10314 (“[A] cir-
`cuit layer requires one or more dielectric layers.... For a
`circuit layer to be substantially flexible, Applicant has
`found that the dielectric material must have low tensile
`stress, for example, 5 x 108 dynes/cm? tensile.”). Consid-
`ered in its entirety, the prosecution history clearly and un-
`ambiguously demonstrates that a substantially flexible
`circuit layer, and similar terms, must contain a substan-
`tially flexible semiconductor substrate and a sufficiently
`low tensile stress dielectric material. We see nothingin the
`specification or prosecution history that limits the dielec-
`tric to a particular stress value. Both merely provide as an
`
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`example that a tensile stress of 5 x 108 dynes/cm?is suffi-
`cient.
`
`This is not, however, the end of the construction. The
`prosecution history makes clear that “substantially flexi-
`ble” cannot be read to coverrigid substrates and circuit lay-
`ers.
`See J.A. 15397 (criticizing the prior art substrate
`because it is “rigid”); J.A. 16039 (stating the prior art “de-
`scribe[s] a stacked integrated circuit formed on a rigid car-
`rier ..., suggesting that the stacked integrated circuit is
`in fact inflexible” (emphasis in original)). Based on expert
`testimony from Dr. Franzon, the Board found that “there
`are a numberof factors that, within the context of semicon-
`ductor processing, determine the flexibility of a semicon-
`ductor substrate,” including the type of semiconductor
`substrate, the crystal orientation of the material, and the
`physical dimensions of the substrate. E.g., J.A. 27 (citing
`J.A. 2191-92 § 71). This suggests thinning the semicon-
`ductor substrate to 50 pm and subsequently polishing or
`smoothing it is necessary but not necessarily sufficient to
`make the substrate substantially flexible. To ensure that
`the construction of “substantially flexible” cannot be read
`to cover a rigid substrate or circuit layer, we interpret a
`substantially flexible semiconductor substrate as a semi-
`conductor substrate that is thinned to 50 um and subse-
`quently polished or smoothed such that it is largely able to
`bend without breaking. Likewise, we interpret a substan-
`tially flexible circuit layer as a circuit layer that is largely
`able to bend without breaking and contains a substantially
`flexible semiconductor substrate and a sufficiently low ten-
`sile stress dielectric material.
`
`II. Obviousness
`
`We review the Board’s legal determinations de novo
`and its underlying factual findings for substantial evi-
`dence. Belden Inc. v. Berk-Tek LLC, 805 F.3d 1064, 1073
`(Fed. Cir. 2013). Obviousnessis a question of law based on
`underlying facts. Id. Whether there was a motivation to
`
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`combine references and a reasonable expectation of success
`in doing so to meetthe limitations of the claimed invention
`are questionsof fact. Intelligent Bio-Sys., Inc. v. Illumina
`Cambridge Litd., 821 F.3d 1359, 1367-68 (Fed. Cir. 2016).
`
`Each ground of unpatentability relied on either Bertin
`or Yu in combination with Leedy, along with other refer-
`ences not relevant on appeal. Bertin discloses “[a] fabrica-
`tion method and resultant three-dimensional multichip
`package having a densely stacked array of semiconductor
`chips interconnected at least partially by meansof a plu-
`rality of metallized trenches.”
`J.A.1206 at Abstract.
`“{P]rocessing begins with a semiconductor device 50 (pref-
`erably comprising a wafer) having a substrate 52 and an
`active layer 54, which is typically positioned at least par-
`tially therein.” J.A. 1216 at 3:50-53. A dielectric layer is
`grownover the active layer. Id. at 3:60-62.6 Yu discloses
`a fabrication process for a 3D integration structure in
`whicha silicon waferis glued to quartz glass, thinned and
`polished, and bonded to a thick wafer. The structure in-
`cludes a “field oxide,” depicted in two figures as silicon di-
`oxide. J.A. 1350. Leedy discloses a methodof fabricating
`“integrated circuits from flexible membranes formed of
`very thin low stress dielectric materials, such as silicon di-
`oxide or
`silicon nitride,
`and semiconductor
`layers.”
`J.A. 1229 at Abstract.
`
`Regarding the Bertin-Leedy combinations, Petitioners
`proposed depositing a low-stress dielectric material using |
`plasma-enhanced chemical vapor deposition (“PECVD”), as
`disclosed in Leedy, instead of growing the dielectric layer,
`as disclosed in Bertin. The Board found that a person of
`ordinary skill in the art would not have been motivated to
`make such a combination and would not have had a rea-
`sonable expectation of success in doing so. It credited the
`
`6 A dielectric is an insulator used inelectric circuits.
`J.A. 2375 J 33.
`
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`testimony of Elm’s expert Dr. Alexander Glew that PECVD
`was incompatible with Bertin’s integrated circuit. Given
`the complexity involved in integrated circuit fabrication,it
`found Dr. Franzon’s testimony that PECVD had certain
`benefits and that Leedy and Bertin are in the same techno-
`logical field was insufficient to meet Petitioners’ burden.
`As a result, it found Petitioners failed to adequately ex-
`plain “how [Bertin’s] fabrication process would be changed
`to use [Leedy’s] dielectric material, which is formed in a
`quite different manner than [Bertin’s] dielectric layer.”
`J.A. 77. The Board’s finding as to a lack of reasonable ex-
`pectation of success is supported by substantial evidence.
`
`Bertin discloses that “[a] dielectric layer 60, for exam-
`ple, [silicon dioxide], is grown over active layer 54 of device
`50.” J.A. 1216 at 3:60-62. Dr. Glew testified that a silicon
`dioxide dielectric that is grown directly over circuit compo-
`nents must be high-purity to not damage thecircuit com-
`ponents. J.A. 2415 § 128. Asaresult, one of ordinary skill
`in the art would have knownfrom Bertin’s description that
`the dielectric layer 60 “was grown at high temperatures us-
`ing thermal oxidation.”
`J.A. 2415-16 { 128; see also
`J.A. 1527 (acknowledging in the Petition that Bertin dis-
`closes “thermally grown oxides”). Thermal oxidation is a
`process in which silicon at the surface of a wafer is con-
`verted to high-purity silicon dioxide by exposingit to oxy-
`gen at high temperatures, typically between 900 °C and
`1200 °C. J.A. 2387-88 {| 66-67.
`
`Substantial evidence supports the Board’s finding that
`Petitioners did not adequately explain how Bertin’s fabri-
`cation process would be changed to use Leedy’s dielectric
`material. The Petition asserted that Leedy’s dielectric ma-
`terial could “easily be used in place of’ Bertin’s dielectric
`using PECVD.
`J.A. 1527.
`In support of this argument,
`Dr. Franzontestified that PECVD “was a commonly avail-
`able deposition technique that could have been used in
`place of’ Bertin’s
`technique for growing dielectrics.
`J.A. 2207 J 101. He also testified that Leedy explains that
`
`

`

`Case: 17-2474
`
`Document:68
`
`Page:14
`
`Filed: 06/12/2019
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`14
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`SAMSUNG ELECTRONICSCO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
`
`“its dielectric deposition processes are compatible with con-
`ventional
`integrated
`circuit
`fabrication methods.”
`J.A. 2206-07 § 101. For example, Leedy states that “[t]he
`dielectric membrane is compatible with most higher tem-
`perature
`[integrated circuit]
`processing techniques.”
`J.A. 1296 at 5:32-33.
`
`Evidence shows that selecting a dielectric and a
`methodof forming that dielectric is more complicated than
`Petitioners suggest. A specific dielectric, like silicon diox-
`ide, can have “vastly different characteristics and behav- °
`iors” depending on how it
`is made.
`J.A.2386 { 63.
`Dr. Glew identified eighteen factors to be considered when
`selecting a dielectric and method of formation. Those fac-
`tors include:
`
`field
`(2)breakdown
`constant,
`(1) dielectric
`(4) surface
`conductance,
`-strength,
`(3) leakage,
`(5) moisture absorption or permeability to mois- '
`ture, (6) stress, (7) adhesion to aluminum, (8) ad-
`hesion to dielectric
`layers
`above or below,
`(9) stability, (10) etch rate, (11) permeability to hy-
`’ drogen,
`(12) amount of
`incorporated electrical
`charge or dipoles,
`(13)amount of
`impurities,
`(14) quality of step coverage, (15) the thickness and
`uniformity of the film, (16) ability to provide good
`doped uniformity across a wafer, (17) defect den-
`sity,
`[and]
`(18) amount of residual constituents
`that outgas during later processing.
`
`J.A. 2421 § 139. Dr. Glew stated that most of these factors
`are unknown here with respect to Leedy’s dielectric, so a
`person of ordinary skill in the art could not conclude that
`it would have been obvious to make the proposed substitu-
`tion.
`In light of the complexity of semiconductor fabrica-
`tion, the Board found Petitioners’ explanation lacking.
`
`The Board’s finding that PECVD is “quite different”
`from thermal oxidation is supported by substantial evi-
`
`

`

`Case: 17-2474
`
`Document:68
`
`Page:15
`
`Filed: 06/12/2019
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`SAMSUNG ELECTRONICS CO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
`
`15
`
`dence. J.A. 77. As the name suggests, PECVD is a deposi-
`tion process, unlike thermal oxidation, which is a growth
`process. PECVD is performed at 400 °C or less and uses
`plasma to create a reaction between the surface of a wafer
`and chemical vapors that include the atomsor molecules to
`be deposited.
`In contrast to thermal oxidation, which
`yields a high-purity dielectric, Dr. Glew testified that die-
`lectrics deposited using PECVD “include impurities that
`make them unusable for a variety of applications requiring
`higher purity.” J.A. 2392 § 77. According to Dr. Glew,this
`creates a problem when attempting to implement Leedy’s
`dielectric into Bertin using PECVD becausethe dielectric
`layer of Bertin must be highly pure to not damage thecir-
`cuit components. J.A. 2415-16 § 128. The dielectric pro-
`duced using PECVD would not be sufficiently pure.
`J.A. 2416 J 130. He also testified that PECVD “cannot be
`used becausepositive ions present in the plasmacanstrike
`and damage the wafer and the exposed active components
`in and on its surface.” J.A. 2423 { 142.
`
`Petitioners argue the Board erred whenit declined to
`resolve a dispute about front-end-of-line and back-end-of-
`line processing steps,
`especially when it
`relied on
`Dr. Glew’s testimony that assumed Bertin’s dielectric was
`grown during the front-end-of-line phase of the fabrication
`process. Dr. Glew’s testimony wasthat if Leedy’s dielectric
`replaced Bertin’s at the same phasein the fabrication pro-
`cess, PECVD could not be used “because the resulting die-
`lectric would not
`(1) be sufficiently pure;
`(2) have the
`ability to adhere sufficiently to the semiconductor wafer;
`and (3) be able to withstand high temperaturesof the re-
`maining [front-end-of-line] steps,” which generally occur at
`higher
`temperatures than the back-end-of-line steps,
`“without changing its form.” J.A. 2422-23 4 142. We see
`no legal error in the Board’s decision. First, the Board
`found that even assuming Petitioners’ contentions were ac-
`curate, their explanation was lacking. Second, we under-
`stand the Board’s opinion as finding it unnecessary to
`
`

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`Case: 17-2474
`
`Document:68
`
`Page: 16
`
`Filed: 06/12/2019
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`16
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`SAMSUNG ELECTRONICSCO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
`
`decide this issue because, at least as to Dr. Glew’s first two
`points, the timing would not matter. Though Petitioners
`disputed these facts in their Reply below, they did so based
`on attorney argument without premising that argument on
`the timing of applying PECVD. J.A. 1811-12. Moreover,
`“t]he possibility of drawing two inconsistent conclusions
`from the evidence does not prevent an administrative
`agency’s finding from being supported by substantial evi-
`dence.” In re Applied Materials, Inc., 692 F.3d 1289, 1294
`(Fed. Cir. 2012).
`
`Petitioners also argue the Board improperly required
`proof that unclaimed elements were combinable.
`“It is
`well-established that a determination of obviousness based
`on teachings from multiple references does not require an
`actual, physical substitution of elements.” In re Mouttet,
`686 F.3d 1322, 1332 (Fed. Cir. 2012). “What matters in the
`§ 103 nonobviousness determination is whethera person of
`ordinary skill in the art, having all the teachingsoftheref-
`erences before him, is able to produce the structure defined
`by the claim.” Orthopedic Equip. Co., Inc. v. United States,
`702 F.2d 1005, 1013 (Fed. Cir. 1983). The Board did not
`require unclaimed elements be combinable. Rather,it re-
`peatedly stated that integrated-circuit technology is com-
`plex and, as such, looked for specific evidence that a person
`of ordinary skill in the art would have reasonably expected
`success in combining Bertin’s fabrication process and
`Leedy’s dielectric material. Petitioners specifically argued
`in its Petition that “PECVD ... could have been used in
`place of the dielectric growing techniques described in Ber-
`tin to obtain the predictable result of stacked [integrated
`circuits] having low tensile stress dielectrics.” J.A. 1528.
`The Board ultimately determined that Petitioners’ evi-
`dence in support of that combination wasinsufficient. We
`will not fault the Board for analyzing Petitioners’ obvious-
`ness grounds in the way presented in the Petition.
`
`

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`Case: 17-2474
`
`Document:68
`
`Page:17
`
`Filed: 06/12/2019
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`SAMSUNG ELECTRONICSCO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
`
`17
`
`Finally, Petitioners argue there was a reasonable éx-
`pectation of success because the Challenged Patents incor-
`porate Leedy by reference.
`The patents state that
`“dielectrics in low stress .
`.
`. such as low stress silicon diox-
`ide and silicon nitride ... are discussed at length in
`[Leedy], incorporated herein by reference.” ’672 patent at
`8:46—-53. Petitioners argue that the failure to mention any
`technical problems with using Leedy’s dielectrics indicates
`that doing so wastrivial. The Board considered this argu-
`ment and rejected it. We find the Petitioners’ argument too
`speculative to warrant a conclusion that the Board’s fac-
`tual finding lacked substantial evidence.
`
`The arguments related to the Yu-Leedy combinations
`were substantially similar to the Bertin-Leedy combina-
`tions. According to the Petition, it would have been obvious
`to replace Yu’s silicon dioxide and processes for formingit
`with the dielectric and deposition process taught by Leedy.
`“Using [Leedy’s] dielectric materials and deposition tech-
`niques in the manufacture of Yu’s 3D LSI results in” the
`combination disclosing the low-tensile-stress-dielectric
`limitation. J.A. 1558. Dr. Franzen’s testimony in support
`of this combination wasidentical to the combination in the
`Bertin-Leedy grounds. See J.A. 2206-08 {J 99-103. The
`Board found that Petitioners failed to meet their burden for
`substantially the same reasons.
`
`The evidence discussed as to why a personof ordinary
`skill in the art would not have reasonably expected success
`in making the proposed combination applies equally here.
`Dr. Glewtestified that Yu identifies its dielectric as a “field
`oxide,” which one of ordinary skill in the art would have
`understoodis a highly pure dielectric grown directly on the
`silicon substrate at high temperatures using thermal oxi-
`dation. J.A. 2418-19 Jf 134-35 (citing J.A. 1350). His tes-
`timony about why a person of ordinary skill in the art
`would not have reasonably expected success using PECVD
`to deposit Leedy’s dielectric was likewise the same. Peti-
`tioners raise no argumenton appeal that distinguishes the
`
`

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`Case: 17-2474
`
`Document:68
`
`Page: 18
`
`Filed: 06/12/2019
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`18
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`SAMSUNG ELECTRONICS CO., LTD. v. ELM 3DS INNOVATIONS,
`LLC
`
`Bert