Vlsi Technology LLC v. Intel Corporation

Case: 21-1826 Document: 54 Page: 1 Filed: 11/15/2022

United States Court of Appeals
for the Federal Circuit
______________________

VLSI TECHNOLOGY LLC,
Appellant

v.

INTEL CORPORATION,
Appellee
______________________

2021-1826, 2021-1827, 2021-1828
______________________

Appeals from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in Nos. IPR2019-
01198, IPR2019-01199, IPR2019-01200.
______________________

Decided: November 15, 2022
______________________

NATHAN NOBU LOWENSTEIN, Lowenstein & Weather-
wax LLP, Santa Monica, CA, argued for appellant. Also
represented by KENNETH J. WEATHERWAX.

S. CALVIN WALDEN, Wilmer Cutler Pickering Hale and
Dorr LLP, New York, NY, argued for appellee. Also repre-
sented by JEFFREY ANDREW DENNHARDT; MARK
CHRISTOPHER FLEMING, JOHN V. HOBGOOD, STEPHANIE LIN,
Boston, MA; RONALD GREGORY ISRAELSEN, Washington,
DC.
______________________
Case: 21-1826 Document: 54 Page: 2 Filed: 11/15/2022

2 VLSI TECHNOLOGY LLC v. INTEL CORPORATION

Before CHEN, BRYSON, and HUGHES, Circuit Judges.
BRYSON, Circuit Judge.
Appellee Intel Corporation filed three petitions for in-
ter partes review (“IPR”) of U.S. Patent No. 7,247,552 (“the
’552 patent”), which is owned by appellant VLSI Technol-
ogy LLC. The Patent Trial and Appeal Board instituted
the IPR proceedings, and in a combined Final Written De-
cision, the Board found all of the challenged claims of the
’552 patent to be unpatentable. For the reasons set forth
below, we affirm in part, reverse in part, and remand.
I
A
The ’552 patent is directed to “[a] technique for allevi-
ating the problems of defects caused by stress applied to
bond pads” of an integrated circuit. ’552 patent, Abstract.
An integrated circuit, sometimes referred to as a “chip”
or “die,” contains numerous electronic circuits that are in-
tegrated on a flat piece of semiconductor called a “sub-
strate.” The specification of the ’552 patent discloses an
integrated circuit that includes several metal “interconnect
layers” positioned above the substrate and frequently sur-
rounded by “dielectric” or insulating material. See id. at
col. 3, ll. 1–10 & Fig. 1. The integrated circuits described
in the ’552 patent also include one or more “bond pads” that
sit above the interconnect layers and are used to attach the
chip to another electronic component, such as a computer
motherboard. See id. at col. 3, ll. 22–25.
When a chip is attached to another electronic compo-
nent, forces are exerted on the chip’s bond pad. Id. at Ab-
stract & col. 5, ll. 53–57. Those forces can result in damage
to the interconnect layers and to the dielectric material
that surrounds those layers. See id. at Abstract & col. 1, ll.
39–42. As such, dedicated support structures made of
metal layers and vias are connected to and provide support
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VLSI TECHNOLOGY LLC v. INTEL CORPORATION 3

for the bond pad. See id. at col. 1, ll. 53–61. In the prior
art, these metal support layers were linked to the bond pad,
and thus were not “functionally independent,” i.e., they
could not be “used for wiring or interconnects unrelated to
the pad.” Id. at col. 1, ll. 58–64.
The ’552 patent discloses improvements to the struc-
tures of an integrated circuit that reduce the potential for
damage to the interconnect layers and dielectric material
when the chip is attached to another electronic component
while also “permit[ing] each of the interconnect layers un-
derlying [the pad] to be functionally independent in the cir-
cuit if desired.” See id. at col. 3, line 64 through col. 4, line
7. Specifically, the ’552 patent discloses that only “a pre-
determined minimum amount of metal or a minimum den-
sity” is needed to “adequately support” the bond pad. See
id. at col. 3, line 64 through col. 4, line 4. If the function-
ally independent interconnect layers underneath the pad
are insufficient to reach a predetermined minimum den-
sity, “dummy metal lines”—i.e., metal lines that do not
serve any electrical purpose—may be added to increase the
metal density of the interconnect layers. See id. at col. 4,
ll. 13–56; see also id. at Fig. 3.
Claim 1 is the only independent apparatus claim of the
’552 patent and is representative of the claimed invention.
It recites as follows:
1. An integrated circuit, comprising:
a substrate having active circuitry;
a bond pad over the substrate;
a force region at least under the bond pad char-
acterized by being susceptible to defects due to
stress applied to the bond pad;
a stack of interconnect layers, wherein each in-
terconnect layer has a portion in the force region;
and
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4 VLSI TECHNOLOGY LLC v. INTEL CORPORATION

a plurality of interlayer dielectrics separating
the interconnect layers of the stack of interconnect
layers and having at least one via for interconnect-
ing two of the interconnect layers of the stack of in-
terconnect layers;
wherein at least one interconnect layer of the
stack of interconnect layers comprises a functional
metal line underlying the bond pad that is not elec-
trically connected to the bond pad and is used for
wiring or interconnect to the active circuitry, the at
least one interconnect layer of the stack of inter-
connect layers further comprising dummy metal
lines in the portion that is in the force region to ob-
tain a predetermined metal density in the portion
that is in the force region.
’552 patent, claim 1. Claim 2 depends from claim 1, and
claim 11 is a method claim generally similar to claim 1.
Claim 20 also plays a role in this appeal. It recites as
follows:
20. A method of making an integrated circuit hav-
ing a plurality of bond pads, comprising:
developing a circuit design of the integrated
circuit;
developing a layout of the integrated circuit ac-
cording to the circuit design, wherein the layout
comprises a plurality of metal-containing intercon-
nect layers that extend under a first bond pad of
the plurality of bond pads, at least a portion of the
plurality of metal-containing interconnect layers
underlying the first bond pad and not electrically
connected to the bond pad as a result of being used
for electrical interconnection not directly connected
to the bond pad;
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VLSI TECHNOLOGY LLC v. INTEL CORPORATION 5

modifying the layout by adding dummy metal
lines to the plurality of metal-containing intercon-
nect layers to achieve a metal density of at least
forty percent for each of the plurality of metal-con-
taining interconnect layers; and
forming the integrated circuit comprising the
dummy metal lines.
’552 patent, claim 20.
B
In 2018, VLSI brought suit in the United States Dis-
trict Court for the District of Delaware, charging Intel with
infringing the ’552 patent. The district court subsequently
conducted a claim construction hearing. In the course of
the hearing, the court construed the term “force region,”
which appears in independent claims 1 and 11 of the ’552
patent. Citing a passage from the ’552 patent, the district
court construed “force region” to mean a “region within the
integrated circuit in which forces are exerted on the inter-
connect structure when a die attach is performed.” J.A.
6017, 6356; see also ’552 patent, col. 3, ll. 49–52.
In June 2019, after the district court action was filed
but before the claim construction proceedings in that ac-
tion, Intel filed its petitions for IPR, challenging the valid-
ity of claims 1, 2, 11, and 20 of the ’552 patent. In the
petition directed to claims 1 and 2, Intel proposed a con-
struction of “force region” that was consistent with the
claim construction that Intel subsequently offered to the
district court and that the district court adopted, i.e., a “re-
gion within the integrated circuit in which forces are ex-
erted on the interconnect structure when a die attach is
performed.” J.A. 6588–89.
VLSI did not oppose Intel’s proposed construction be-
fore the Board. It soon became evident, however, that al-
though the parties purported to agree on the construction
to be given to the term “force region,” their agreement was
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6 VLSI TECHNOLOGY LLC v. INTEL CORPORATION

merely apparent, because they disagreed as to the meaning
of the term “die attach.”
Intel argued that the term “die attach” refers to any
method of attaching the chip to another electronic compo-
nent, and that the term “die attach” therefore includes at-
tachment by a method known as wire bonding. J.A. 6594
(Petition in IPR2019-1198); J.A. 6789–93 (Petitioner’s Re-
ply to Patent Owner’s Preliminary Response); J.A. 7063–
70 (Petitioner’s Reply); J.A. 7286–87 (Oral Hearing before
the Board). VLSI, on the other hand, argued that the term
“die attach” refers to a method of attachment known as “flip
chip” bonding, and does not include wire bonding. See J.A.
6720–29 (Patent Owner’s Preliminary Response); J.A.
7005–14 (Patent Owner’s Response); J.A. 7100–05 (Patent
Owner’s Sur-Reply to Petitioner’s Reply to the Patent
Owner’s Response); see also J.A. 7299–7300 (Oral Hearing
before the Board in which counsel for Intel noted that alt-
hough the parties agreed on the construction of “force re-
gion,” they disagreed on the meaning of the term “die
attach”).
Applying its proposed restrictive definition of “die at-
tach,” VLSI distinguished Intel’s principal prior art refer-
ence for the “force region” limitation, U.S. Patent
Publication No. 2004/0150112 (“Oda”). That reference dis-
closes attaching a chip to another component using wire
bonding. Based on its contention that the term “die attach”
does not encompass attachment by wire bonding, VLSI ar-
gued that Oda does not disclose a “force region” within the
meaning of the claims of the ’552 patent as construed by
the district court.
In its Institution Decisions, the Board stated that
“based on the current record,” it disagreed with VLSI that
the method of performing a “die attach” cannot include the
method of wire bonding. J.A. 6846, 20006. The Board
pointed out that Intel had provided argument and evidence
that wire bonding is a type of die attach, and that Oda
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VLSI TECHNOLOGY LLC v. INTEL CORPORATION 7

therefore disclosed a “force region” under Intel’s claim con-
struction, i.e., a region within the integrated circuit in
which forces are exerted on the interconnect structure
when a die attach is performed. J.A. 6846–47, 20006–07.
In addition, the Board noted that Intel asserted that the
“force region” includes regions directly under the bond pad,
and that VLSI’s proposed construction during the district
court proceeding also included regions directly under the
bond pad. J.A. 6845, 20005–06. The Board then stated
that a construction of “force region” that includes regions
at least under the bond pad “is consistent with the plain
language of claim[s] 1” and 11. See J.A. 6845, 20005.
In its Final Written Decision, unlike in the Institution
Decisions, the Board did not resolve the parties’ dispute re-
garding the meaning of the term “die attach.” Instead, the
Board construed the term “force region” as “including at
least the area directly under the bond pad.” Intel Corp. v.
VLSI Tech. LLC, Nos. IPR2019-01198, IPR2019-01199,
IPR2019-01200, 2021 WL 388740, at *6 (P.T.A.B. Feb. 3,
2021). The Board also found that the ’552 patent specifica-
tion made clear in several places that the term “force re-
gion” was not limited to flip chip bonding, but could include
wire bonding as well. Id. at *7. Based on that finding, the
Board concluded that Oda disclosed the “force region” ele-
ment of claims 1, 2, and 11, and that those claims were un-
patentable for obviousness. Id. at *12–13.
With respect to claim 20 of the ’552 patent, the parties
disagreed over the construction of the limitation providing
that the “metal-containing interconnect layers” are “used
for electrical interconnection not directly connected to the
bond pad.” VLSI argued that the phrase requires a connec-
tion to active circuitry or the capability to carry electricity.
Id. at *8. Intel argued that the claim does not require that
the interconnection actually carry electricity. See id. The
Board sided with Intel; it found that “[c]laim 20 does not
recite ‘active circuitry’” and declined “to import [that] limi-
tation into claim 20.” Id. at *9. The Board therefore
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8 VLSI TECHNOLOGY LLC v. INTEL CORPORATION

construed the phrase to encompass interconnect layers
that are “electrically connected to each other but not elec-
trically connected to the bond pad.” Id. at *10.
Intel relied principally upon U.S. Patent No. 7,102,223
(“Kanaoka”) as teaching the “used for electrical intercon-
nection” limitation in claim 20 as construed by the Board.
Figure 45 of Kanaoka discloses a die that has a series of
interconnect layers, some of which are connected to each
other by vertical metal structures called “vias.” J.A. 7655;
see also Appellee’s Br. 6–7. Because the interconnect layers
disclosed in Kanaoka were electrically connected to one an-
other but not to the bond pad, the Board found that Ka-
naoka disclosed the “used for electrical interconnection”
limitation of claim 20. Intel, 2021 WL 388740, at *28.
Based on its analysis, the Board concluded that all the
challenged claims (claims 1, 2, 11, and 20) of the ’552 pa-
tent were unpatentable. Id. at *29. VLSI appealed.
II
VLSI raises two principal issues on appeal. First, VLSI
argues that the Board erred in its treatment of the “force
region” limitation of claims 1, 2, and 11. Second, VLSI ar-
gues that the Board erred in construing the phrase “used
for electrical interconnection” in claim 20 to encompass a
metallic structure that is not connected to active circuitry.
We affirm with respect to the first issue, and we reverse
and remand with respect to the second.
A
1
With regard to the “force region” limitation, VLSI ar-
gues that the Board erred in declining to adopt the con-
struction of “force region” that was proposed by Intel and
adopted by the district court. Specifically, VLSI argues
that the Board failed to acknowledge and give appropriate
weight to the district court’s claim construction. VLSI
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VLSI TECHNOLOGY LLC v. INTEL CORPORATION 9

bases its argument principally on the Patent and Trade-
mark Office procedures that require the Board to “con-
sider” prior claim construction determinations by a district
court and give such prior constructions appropriate weight.
See 37 C.F.R. § 42.100(b); see also Power Integrations, Inc.
v. Lee, 797 F.3d 1318, 1326–27 (Fed. Cir. 2015); Patent
Trial and Appeal Board, Consolidated Trial Practice Guide
46–47 (Nov. 2019); Changes to the Claim Construction
Standard for Interpreting Claims in Trial Proceedings Be-
fore the Patent Trial and Appeal Board, 83 Fed. Reg.
51,340, 51,354 (Oct. 11, 2018).
We reject VLSI’s argument regarding the asserted reg-
ulatory violation for several reasons. First, while it is true
that the Board did not specifically mention the district
court’s claim construction in its Final Written Decision, the
Board was clearly well aware of that construction, as the
district court’s construction was the subject of repeated and
extensive discussion in the briefing and in the oral hearing
before the Board. See J.A. 6720 (Patent Owner’s Prelimi-
nary Response); J.A. 6954, 7001 (Patent Owner’s Re-
sponse); J.A. 7099–7100 (Patent Owner’s Sur-reply); J.A.
7328, 7333–35 (Oral Hearing).
Second, the Board did not reject the district court’s con-
struction. Instead, in light of the arguments made by the
parties before the Board, it was clear that the apparent
agreement as to the district court’s construction concealed
a fundamental disagreement between the parties as to the
proper construction of “force region.” The Board recognized
that simply adopting Intel’s proposed construction would
not resolve the true dispute between the parties, which
turned on whether the term “force region,” as used in the
’552 patent, was limited to flip chip bonding or covered wire
bonding as well. See J.A. 6838, 6846–47. Although the dis-
trict court defined the term “force region” with reference to
“die attach” processes, the district court did not decide—
and was not asked to decide—whether the term “die at-
tach,” as used in the patent, included wire bonding or was
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10 VLSI TECHNOLOGY LLC v. INTEL CORPORATION

limited to flip chip bonding. See generally VLSI Tech. LLC
v. Intel Corp., No. 18-cv-966, Dkt. No. 228 (D. Del. Aug. 19,
2019) (Joint Claim Construction Brief). Thus, the Board
addressed an argument not made to the district court, and
it reached a conclusion not at odds with the conclusion
reached by the district court. See Consolidated Trial Prac-
tice Guide 47 (noting that the “facts and circumstances of
each case will be analyzed as appropriate”).
Finally, we conclude that the Board’s treatment of the
term “force region” was not erroneous, for the reasons we
address below. Because the parties’ positions before the
Board made it clear that the Board needed to go beyond the
district court’s claim construction in order to resolve the
parties’ dispute, it was unnecessary for the Board to advert
to the district court’s claim construction. Therefore, even
if it might have been useful for the Board to begin by ex-
pressly acknowledging the district court’s claim construc-
tion, the Board was not required to do so, and any failure
to do so was at most harmless error.
2
As to the merits of the Board’s claim construction, we
conclude that the Board’s claim construction of “force re-
gion” and its application of that construction to the Oda
reference were not inconsistent with the proper construc-
tion of “force region.”
Both Intel and the district court relied on a passage
from column 3 of the ’552 patent as providing support for
Intel’s proposed construction of the term “force region.”
That passage explains that “[t]he force region 64 is a region
within the integrated circuit 10 in which forces are exerted
on the interconnect structure when a die attach is per-
formed.” ’552 patent, col. 3, ll. 49–52. Like the Board, we
conclude that the passage in column 3 is directed to the
embodiment disclosed in Figures 1 and 2 of the ’552 patent.
See Intel, 2021 WL 388740, at *7. Thus, even if the term
“die attach,” as used in the ’552 patent, were construed to
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VLSI TECHNOLOGY LLC v. INTEL CORPORATION 11

include only flip chip bonding, that would not affect the
construction of the term “force region.” As we have repeat-
edly cautioned, claims should not be limited “to preferred
embodiments or specific examples in the specification.” Te-
leflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313, 1328
(Fed. Cir. 2002) (quoting Comark Commc’ns, Inc. v. Harris
Corp., 156 F.3d 1182, 1186 (Fed. Cir. 1998)). It was there-
fore unnecessary for the Board to determine whether the
term “die attach,” as used in column 3 of the ’552 patent,
excludes wire bonding.
Even if the term “die attach,” as used in column 3 of the
’552 patent, is understood to refer to flip chip bonding in
particular and not to other forms of attachment such as
wire bonding, other portions of the specification make clear
that the invention is not limited to flip chip bonding. The
specification specifically calls out wire bonding mecha-
nisms, stating that examples of an interconnect pad within
the scope of the invention “include, but are not limited to,
a wire bond pad, a probe pad, a flip-chip bump pad, a test
point or other packaging or test pad structures that may
require underlying structural support.” ’552 patent, col. 2,
ll. 42–45.
In addition, as the Board noted, other language in the
specification indicates that the claimed “force region” is not
limited to attachment processes that use flip chip bonding.
See Intel, 2021 WL 388740, at *7. For example, with re-
spect to another embodiment of the invention, the specifi-
cation states that “[i]n another form the force region is a
region in which the interconnect layers . . . are susceptible
to stress from the bond pad due to assembly or other pro-
cesses.” ’552 patent, col. 6, ll. 25–29 (emphasis added).
Likewise, the specification elsewhere states that a force re-
gion “is identified around and under the bond pad charac-
terized by being susceptible to defects due to contacts to the
bond pad.” Id. at col 5, ll. 55–57. Based on those portions
of the specification, the Board found that the Oda reference
reads on the “force region” limitation.
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12 VLSI TECHNOLOGY LLC v. INTEL CORPORATION

We conclude that the correct construction of the term
“force region” is the definition provided in column 6 of the
’552 patent. That is, “force region” is construed to mean “a
region in which the interconnect layers are susceptible to
stress from the bond pad due to assembly or other pro-
cesses.” See ’552 patent, col. 6, ll. 25–29. Under that con-
struction, stresses on the interconnect layers resulting
from any assembly process, including wire bonding, would
fall within the scope of the term “force region.” The Board’s
treatment of that limitation is not inconsistent with our
construction. In fact, the Board relied on the same lan-
guage from column 6 of the ’552 patent in concluding that
the Oda reference discloses the “force region” of claim 1.
Intel, 2021 WL 388740, at *13.
The Board was able to resolve the case by construing
the term “force region” to include at least the area directly
under the bond pad and by not limiting the term to situa-
tions in which the flip chip bonding method is used. That
construction is not inconsistent with our construction. The
Board therefore properly found that the Oda reference, in
combination with other references cited to the Board, made
claims 1, 2, and 11 unpatentable.
3
VLSI raises two other challenges to the Board’s con-
struction of the term “force region.” First, it contends that
defining “force region” to mean a region at least directly
under the bond pad is legally flawed because the definition
restates a requirement that is already in the claims, which
refer in the case of claim 1 to a “force region at least under
the bond pad” and in the case of claim 11 to “a force region
at least under the first bond pad of the plurality of bond
pads.” That construction, according to VLSI, would violate
the principle that construing claims to include features of
the term that are already recited in the claims “would
make those expressly recited features redundant,” and that
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VLSI TECHNOLOGY LLC v. INTEL CORPORATION 13

“[i]deally” such constructions should be avoided. Apple,
Inc. v. Ameranth, 842 F.3d 1229, 1237 (Fed. Cir. 2016).
While a construction that introduces redundancy into
a claim is disfavored, it is not foreclosed. See SimpleAir,
Inc. v. Sony Ericsson Mobile Commc’ns AB, 820 F.3d 419,
429 (Fed. Cir. 2016). That is particularly true where, as in
this case, intrinsic evidence makes it clear that the “redun-
dant” construction is correct. To be sure, the claim lan-
guage in question could have been drafted more precisely.
But the meaning of the claim limitation referring to the
force region is clear: The claim identifies a region that is
“at least under the bond pad” and is “characterized by be-
ing susceptible to defects due [to] stress applied to the bond
pad,” and it refers to that region as the “force region.”
Thus, the “force region” limitation is best understood as
containing a definition of the force region, just as would be
the case if the language of the limitation had read “a region,
referred to as a force region, at least under the bond
pad . . .” or “a force region, i.e., a region at least under the
bond pad . . . .” As such, that language from the claims is
best viewed not as redundant, but merely as clumsily
drafted.
VLSI’s second argument is that when the parties to an
IPR proceeding agree to a particular construction of a claim
term, the Board is bound by that construction, regardless
of whether the construction to which the parties agree is
actually the proper construction of that term. See Oral Ar-
gument at 14:22–22:04; see also Appellant’s Reply Br. 12–
14. In support of its argument regarding that prohibition,
VLSI cites the Supreme Court’s decision in SAS Institute
v. Iancu, 138 S. Ct. 1348 (2018), and our decisions in Kon-
inklijke Philips N.V. v. Google LLC, 948 F.3d 1330 (Fed.
Cir. 2020), and In re Magnum Oil Tools International, Ltd.,
829 F.3d 1364 (Fed. Cir. 2016).
We disagree with VLSI’s reading of those cases. In
SAS, the Court held that the petition “guide[s] the life of
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14 VLSI TECHNOLOGY LLC v. INTEL CORPORATION

the litigation” in an IPR proceeding. SAS, 138 S. Ct. at
1356. In Koninklijke, we reaffirmed the principle that “it
is the petition, not the Board’s discretion, that defines the
metes and bounds of an [IPR].” Koninklijke, 948 F.3d at
1336. And in Magnum Oil, we held that “the Board must
base its decision on arguments that were advanced by a
party, and to which the opposing party was given a chance
to respond.” Magnum Oil, 829 F.3d at 1381. Each of those
cases stands for the proposition that the petition defines
the scope of the IPR proceeding and that the Board must
base its decision on arguments that were advanced by a
party and to which the opposing party was given a chance
to respond. None of those cases prohibits the Board from
construing claims in accordance with its own analysis. To
the contrary, we have held that the Board is not limited to
the claim constructions proffered by the parties, but may
adopt its own claim construction of a disputed claim term.
See, e.g., WesternGeco LLC v. ION Geophysical Corp., 889
F.3d 1308, 1328–29 (Fed. Cir. 2018); Uniloc 2017 LLC v.
Facebook Inc., 989 F.3d 1018, 1032–33 (Fed. Cir. 2021).
Although the parties may have agreed to apply the lan-
guage of the district court’s construction of “force region,”
this was not a case in which the parties actually agreed on
the proper claim construction. As we explained above, it is
true that Intel proposed to construe “force region” as “a re-
gion within the integrated circuit in which forces are ex-
erted on the interconnect structure when a die attach is
performed,” and that VLSI did not oppose that construc-
tion. But the parties’ purported agreement concealed a
fundamental disagreement about the meaning of that con-
struction. Because of the parties’ very different under-
standings of the meaning of the term “die attach,” it was
clear in the Board proceedings that there was no real
agreement on the proper claim construction. In that
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VLSI TECHNOLOGY LLC v. INTEL CORPORATION 15

situation, it was proper for the Board to adopt its own con-
struction of a disputed claim term. 1
For the foregoing reasons, we conclude that the Board’s
analysis of the “force region” limitation was not erroneous.
Because VLSI raises no other challenges to the Board’s de-
cision that claims 1, 2, and 11 are unpatentable, 2 we affirm
the Board’s decision with respect to those claims.
B
VLSI next argues that the Board erred in construing
the phrase “used for electrical interconnection not directly
connected to the bond pad,” which appears in claim 20 of
the ’552 patent. The Board held that this phrase encom-
passes interconnect layers that are “electrically connected
to each other but not electrically connected to the bond pad”
or to any other active circuitry. Id. at *10. VLSI argues
that the Board should have construed the phrase to require

1 In its reply brief, VLSI argues that judicial estoppel
and waiver preclude Intel from advocating for the Board’s
claim construction. Given that the proceedings before the
Board revealed that the parties disagreed as to the mean-
ing of the term “die attach,” it was appropriate for the
Board to adopt, and Intel to advocate for, a construction
that captured the essence of Intel’s position, i.e., that the
term “force region” referred to a region at least under the
bond pad that was susceptible to defects due to stress ap-
plied to the bond pad, regardless of the type of bonding that
was responsible for causing that stress.
2 We note that VLSI has expressly waived any due
process challenge to the Board’s construction of “force re-
gion.” See Oral Argument at 18:47–18:53. In particular,
VLSI has not suggested that it lacked notice of the Board’s
construction of that term or an opportunity to contest that
construction.
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16 VLSI TECHNOLOGY LLC v. INTEL CORPORATION

that the interconnect layers be connected to active circuitry
or have the capability to carry electricity.
VLSI argues that under its proposed construction, the
Kanaoka reference does not disclose the “used for electrical
interconnection” limitation of claim 20, because the metal-
lic layers are connected by the vias only to one another;
they do not carry electricity and are not electrically con-
nected to any other components.
We agree with VLSI that the Board’s construction of
the phrase “used for electrical interconnection not directly
connected to the bond pad” was too broad. Two aspects of
the claims make this point clear. First, the use of the words
“being used for” in the claim imply that some sort of actual
use of the metal interconnect layers to carry electricity is
required. Second, the recitation of “dummy metal lines”
elsewhere in claim 20 implies that the claimed “metal-con-
taining interconnect layers” are capable of carrying elec-
tricity; otherwise, there would be no distinction between
the dummy metal lines and the rest of the interconnect
layer.
The file history of the ’552 patent provides further sup-
port for that conclusion. The phrase “used for electrical in-
terconnection not directly connected to the bond pad” was
added to claim 20 during prosecution of the ’552 patent.
The underlined language below was added to claim 20 at
that time:
20. A method of making an integrated circuit hav-
ing a plurality of bond pads, comprising:
developing a circuit design of the integrated
circuit;
developing a layout of the integrated circuit ac-
cording to the circuit design, wherein the layout
comprises a plurality of metal-containing intercon-
nect layers that extend under a first bond pad of
the plurality of bond pads, at least a portion of the
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VLSI TECHNOLOGY LLC v. INTEL CORPORATION 17

plurality of metal-containing interconnect layers
underlying the first bond pad and not electrically
connected to the first bond pad as a result of being
used for electrical interconnection not directly con-
nected to the bond pad;
modifying the layout by adding dummy metal
lines to the plurality of metal-containing intercon-
nect layers to achieve a metal density of at least
forty percent for each of the plurality of metal-con-
taining interconnect layers; and
forming the integrated circuit comprising the
dummy metal lines.
J.A. 272–73 (emphasis added). The Board observed that
the amendment to claim 20 appeared to address what “the
metal interconnect layers could not be attached to (i.e., the
bond pad), rather than limiting what [they] must be con-
nected to.” Intel, 2021 WL 388740, at *9.
The problem with that observation is that it does not
explain the addition of the phrase “as a result of being used
for electrical interconnection not directly to the bond pad.”
That phrase could be eliminated from the inventor’s pro-
posed amendment and the claim would still require that
the interconnect layers not be electrically connected to the
bond pad. Presumably, that phrase was meant to serve
some purpose and should be construed to have some inde-
pendent meaning. See Merck & Co. v. Teva Pharms. USA,
Inc., 395 F.3d 1364, 1372 (Fed. Cir. 2005) (“A claim con-
struction that gives meaning to all the terms of the claim
is preferred over one that does not do so.”). Indeed, the ap-
plicant argued in the context of claim 1 that “none of the
area under the [prior art] bond pad may be used for wiring
or interconnect[ion] unrelated to the pad,” J.A. 8176, and
argued that claim 20 was allowable for the same reason,
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18 VLSI TECHNOLOGY LLC v. INTEL CORPORATION

J.A. 8178. 3 In context, that independent meaning of “as a
result of being used for electrical interconnection not di-
rectly to the bond pad” would seem to require that the in-
terconnect layers be used for conducting electricity to
components other than the bond pad.
In support of the Board’s construction, Intel points out
that VLSI’s expert admitted that two interconnect layers
can be “electrically connected” even if they do not carry
electricity and even if they are not connected to any struc-
ture other than each other. See J.A. 8555–56. The problem
with that argument is that the claim does not use the words
“electrically connected.” Instead, it recites the phrase “be-
ing used for electrical interconnection.” And, as noted, the
words “being used for” imply that the interconnect layers
are at least capable of carrying electricity.
We therefore adopt VLSI’s proposed construction of
“used for electrical interconnection.” That is, the phrase
requires the interconnect layers to be capable of carrying
electricity or be connected to active circuitry. The Board’s
construction of that phrase must therefore be reversed. We
remand the patentability determination of claim 20 to the
Board to assess Intel‘s obviousness arguments regarding
that claim in light of our construction of the “used for elec-
trical interconnection” limitation.
III
In summary, the Board’s treatment of the term “force
region” was not erroneous, and its decision that claims 1,
2, and 11 are unpatentable is therefore affirmed. Because
the Board erred in construing the phrase “used for electri-
cal interconnection,” we reverse the Board’s construction of

3 Claim 1 was amended, in part, to recite: “a func-
tional metal line underlying the bond pad that is not elec-
trically connected to the bond pad and is used for wiring or
interconnect to active circuitry.” J.A. 8171.
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VLSI TECHNOLOGY LLC v. INTEL CORPORATION 19

that phrase and remand for further proceedings regarding
claim 20.
No costs.
AFFIRMED-IN-PART, REVERSED-IN-PART, AND
REMANDED