Seoul Semiconductor Co., Ltd.

Patent Trials and Appeals Board

Jun 25, 2021

IPR2020-00146 (P.T.A.B. Jun. 25, 2021)

Trials@uspto.gov Paper 44
571-272-7822 Entered: June 25, 2021

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

SATCO PRODUCTS, INC.,
Petitioner,

v.

SEOUL SEMICONDUCTOR CO, LTD.,
Patent Owner.
____________

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Patent 7,667,225 B1
____________

Before ERICA A. FRANKLIN, JEFFREY W. ABRAHAM, and
ELIZABETH M. ROESEL, Administrative Patent Judges.

ABRAHAM, Administrative Patent Judge.
JUDGMENT
Final Written Decision
Determining No Challenged Claims Unpatentable
35 U.S.C. § 318(a)

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I. INTRODUCTION
Satco Products, Inc. (“Petitioner”), filed a Corrected Petition (Paper 6,
“Pet.”) requesting inter partes review of claims 1, 4–7, 10, 11, and 16–19 of
U.S. Patent No. 7,667,225 B1 (Ex. 1001, “the ’225 patent”). Seoul
Semiconductor Co., Ltd. (“Patent Owner”), filed a Preliminary Response to
the Petition (Paper 8, “Prelim. Resp.”).
On July 2, 2020, we instituted inter partes review of all of the
challenged claims based on all of the grounds identified in the Petition.
Paper 9 (“Inst. Dec.”). Subsequently, Patent Owner filed a Response (Paper
18, “PO Resp.”), Petitioner filed a Reply (Paper 27, “Reply”), and Patent
Owner filed a Sur-reply (Paper 34, “Sur-reply”). We held an oral hearing on
April 8, 2021, and a transcript of the hearing has been entered into the
record. Paper 43 (“Tr.”).
We have jurisdiction under 35 U.S.C. § 6. This Final Written
Decision is issued pursuant to 35 U.S.C. § 318(a). For the reasons that
follow, we determine that Petitioner has not shown by a preponderance of
the evidence that claims 1, 4–7, 10, 11, and 16–19 of the ’225 patent are
unpatentable.
A. Related Proceedings
The parties identify Seoul Semiconductor Co., Ltd. v. Satco Products,
Inc., No. 2:19-cv-04951 (E.D.N.Y.), and Seoul Semiconductor Co., Ltd. v.
The Factory Depot Advantages, Inc., No. 2:19-cv-05065 (C.D. Cal.). Pet.
58–59; Paper 4, 1. Patent Owner additionally identifies Seoul
Semiconductor Co., Ltd. v. Vividgro, Inc., No. 6:19-cv-02263 (M.D. Fla.),
and Seoul Semiconductor Co., Ltd., v. Healthe, Inc., No. 6:19-cv-02264
(M.D. Fla.). Paper 4, 1.
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B. The ’225 Patent
The ’225 patent, titled “Light Emitting Device,” issued on February
23, 2010. Ex. 1001, codes (45), (54). The ’225 patent is directed to a light
emitting device configured to improve the crystal quality of a multi-quantum
well structure and to “prevent a reduction in internal quantum efficiency
which is caused by crystal defects such as dislocations in an active region.”
Ex. 1001, 2:6–12. The devices of the ’225 patent can be used in light
emitting diodes (LEDs) and laser diodes. Ex. 1001, 1:16–18.
The ’225 patent explains that LEDs generally include an n-type
semiconductor layer, a p-type semiconductor layer, and an active region
disposed between the semiconductor layers. Ex. 1001, 1:35–38. “The n-
type and p-type semiconductor layers may be formed of Group-III nitride
semiconductor layers, for example, (Al, In, Ga)N-based compound
semiconductor layers . . . .” Ex. 1001, 1:38–41. According to the ’225
patent, when Group-III nitride semiconductor layers are grown on a
heterogeneous substrate having a hexagonal structure, such as sapphire or
silicon carbide, “the semiconductor layer undergoes cracking or warpage
and dislocations due to differences in lattice constant and thermal expansion
. . . coefficient between the semiconductor layer and the substrate.” Ex.
1001, 1:50–58. “Further, the crystal defects such as dislocations in the
active region trap carriers introduced into the active region and do not emit
light, thereby acting as a non-radiative center and significantly deteriorating
internal quantum efficiency of the LED.” Ex. 1001, 1:65–2:2.
To prevent the deterioration of internal quantum efficiency, the ’225
patent includes at least one carrier trap portion in at least one layer of the
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active region. Ex. 1001, 4:11–14. The term carrier trap portion in the ’225
patent refers to
a structure capable of using carriers which can be trapped and
lost by the dislocations. Such a structure is not limited to a
physical shape. In other words, according to embodiments of the
invention, the carrier trap portion . . . may be a physical shape or
a quantum-mechanical energy state capable of efficiently using
the carriers which can be trapped and lost by the dislocations.
Ex. 1001, 4:40–47.
According to the ’225 patent, the carrier trap portions improve
internal quantum efficiency by trapping carriers that otherwise would be
trapped by dislocations in the multi-quantum well structure so that the
carriers can be used for light emission. Ex. 1001, 6:8–15. “For this purpose,
the carrier trap portion . . . is configured to have a band-gap energy that
gradually decreases from a periphery of the carrier trap portion . . . to the
center thereof . . . .” Ex. 1001, 4:16–19. The ’225 patent teaches that this
can be accomplished “by controlling the temperature, pressure and flow rate
of a source gas in a chamber during growth of the well layer.” Ex. 1001,
4:30–32. As one example, the ’225 patent discloses that for a well layer
composed of InGaN, “when the indium content exceeds 5% and the growth
temperature exceeds 600° C., indium is subjected to phase separation in the
layer and exhibit[s] an intensive tendency to form the carrier trap portion . . .
according to the embodiments of the invention.” Ex. 1001, 4:57–5:7.
Additionally, applying a pressure of 300 torr or more can result in a carrier
trap cluster formed by clustering of at least two carrier trap portions. Ex.
1001, 2:61–62, 5:59–62.
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C. Illustrative Claim
Petitioner challenges claims 1, 4–7, 10, 11, and 16–19 of the ’225
patent. Independent claim 1, the only independent claim challenged, is
illustrative and is reproduced below:
1. A light emitting device, comprising:
a substrate;
a first semiconductor layer on the substrate;
a second semiconductor layer on the first semiconductor
layer; and
a multi-quantum well structure comprising at least one
well layer and at least one barrier layer between the first
and second semiconductor layers, at least one layer
within the multi-quantum well structure comprising at
least one carrier trap portion formed therein, the at least
one carrier trap portion having a band-gap energy
decreasing from a periphery of the carrier trap portion to
a center of the carrier trap portion.
Ex. 1001, 6:42–55.
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D. Reviewed Unpatentability Challenges
Claim(s) Challenged 35 U.S.C. §1 Reference(s)/Basis
1, 4–7, 10, 11, 17–19 102(b) Lin2
4 103(a) Lin, Schley3
16 103(a) Lin, Lin II4
1, 5–7, 10, 11, 17–19 102(b) Gerthsen5
16 103(a) Gerthsen, Lin II

II. ANALYSIS
A. Claim Construction
In an inter partes review, we construe claim terms according to the
standard set forth in Phillips v. AWH Corp., 415 F.3d 1303, 1312–17 (Fed.
Cir. 2005) (en banc). See 37 C.F.R. § 42.100(b) (2019). Under Phillips,

1 The Leahy-Smith America Invents Act (“AIA”), Pub. L. No. 112-29, 125
Stat. 284, 287–88 (2011), amended 35 U.S.C. § 103, effective March 16,
2013. Because the application from which the ’225 patent issued was filed
before this date, the pre-AIA version of §§ 102 and 103 apply.
2 Lin et al., Effects of post-growth thermal annealing on the indium
aggregated structures in InGaN/GaN quantum wells, J. of Crystal Growth,
Vol. 242, 35–40 (2002) (Ex. 1025).
3 Schley et al., Dielectric function and Van Hove singularities for In-rich
InxGa1-xN alloys: Comparison of N- and metal-face materials, Physical
Review B 75, 205204 (2007) (Ex. 1055).
4 Lin et al., Dependence of composition fluctuation on indium content in
InGaN/GaN multiple quantum wells, Appl. Phys. Lett., Vol. 77, No. 19,
2988–2990 (Nov. 6, 2000) (Ex. 1016).
5 Gerthsen et al., Indium distribution in epitaxially grown InGaN layers
analyzed by transmission electron microscopy, Phys. Stat. Sol (c), Vol. 0,
No. 6, 1668–1683 (2003) (Ex. 1026).
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claim terms are afforded “their ordinary and customary meaning.” Phillips,
415 F.3d at 1312. “[T]he ordinary and customary meaning of a claim term
is the meaning that the term would have to a person of ordinary skill in the
art in question at the time of the invention . . . .” Id. at 1313. “Importantly,
the person of ordinary skill in the art is deemed to read the claim term not
only in the context of the particular claim in which the disputed term
appears, but in the context of the entire patent, including the specification.”
Id.
Petitioner proposes an express construction for the term “carrier trap
portion[s]” and contends that the remaining terms of the ’225 patent should
be interpreted according to their ordinary and customary meaning.6 Pet. 19–
21. With regard to “carrier trap portion,” Petitioner contends the ’225 patent
explicitly defines the term in the following passage:
Herein, the carrier trap portion 27 refers to a structure capable of
using carriers which can be trapped and lost by the dislocations.
Such a structure is not limited to a physical shape. In other
words, according to embodiments of the invention, a carrier trap
portion 27 may be a physical shape or a quantum-mechanical
energy state capable of efficiently using carriers which can be
trapped and lost by the dislocations.
Ex. 1001, 4:40-47. Petitioner further contends that a person of ordinary skill
in the art “would have understood that ‘quantum-mechanical energy state[s]
capable of efficiently using carriers which can be trapped and lost by the
dislocations’ are often called ‘quantum dots’ in the literature.” Pet. 20.

6 Petitioner states that “[t]here are problems with the way that the ‘multi-
quantum well structure’ is recited in claim 1,” but does not propose an
express construction for the term. Pet. 20–21.
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Patent Owner does not dispute Petitioner’s assertions regarding the
meaning of “carrier trap portion.” Patent Owner argues, however, that the
preamble of claim 1, which recites a “light emitting device,” is limiting and
requires a semiconductor device that emits light when electric current passes
through it. PO Resp. 11–19. Petitioner disagrees. Reply 3–7.
After reviewing the parties’ arguments and evidence, we determine
that we do not need to expressly construe any terms for purposes of this
Decision, and we do not need to determine whether the preamble is limiting.
See Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co., 868 F.3d
1013, 1017 (Fed. Cir. 2017) (citing Vivid Techs., Inc. v. Am. Sci. & Eng’g,
Inc., 200 F.3d 795, 803 (Fed. Cir. 1999) (“[O]nly those terms need be
construed that are in controversy, and only to the extent necessary to resolve
the controversy.”)).
B. Level of Ordinary Skill in the Art
Petitioner contends that a person of ordinary skill in the art in the field
of the ’225 patent would have had “a Master’s Degree in chemical
engineering, materials engineering, or electrical engineering (with a focus on
semiconductor materials), or similar advanced post-graduate education in
this area, with roughly two years of experience in researching nitride-based
light emitting devices.” Pet. 18–19 (citing Ex. 1002 ¶ 27). Petitioner also
contends that someone “with less education but more relevant practical
experience, depending on the nature of that experience and degree of
exposure to nitride-based light emitting semiconductor materials and their
chemistry and physics, could also qualify as a person of ordinary skill in the
art in the field of the ’225 patent.” Pet. 19.
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Patent Owner contends that a person of ordinary skill in the art
“would have had an undergraduate degree in chemical engineering, material
science, electrical engineering, applied physics, or an equivalent field of
study, and at least two years of professional experience in fabricating Group-
III nitride LEDs or laser diodes,” or, alternatively, “a graduate degree in one
of those fields and at least one year of professional experience.” PO Resp.
21.
We discern only a slight difference between the parties’ proposed
definitions. Moreover, the parties agree that the level of skill in the art
would not materially impact the outcome of this proceeding. PO Resp. 21
(“The challenged claims should be upheld under any of the proposed levels
of ordinary skill in the art.”); Tr. 54:2–13, 59:20–60:12 (counsel for
Petitioner stating that “we have not briefed [the level of ordinary skill in the
art] as materially impacting the outcome of this case”).
In view of the foregoing, we adopt Petitioner’s proposal regarding the
level of one of ordinary skill in the art. The level of ordinary skill in the art
is also reflected by the prior art of record. See Okajima v. Bourdeau, 261
F.3d 1350, 1355 (Fed. Cir. 2001). We, however, also agree with the parties
that the level of skill in the art does not materially impact the outcome of this
proceeding.
C. Overview of Asserted Art
1. Lin (Ex. 1025)
Lin studied the formation of quantum dots (QDs) in InGaN/GaN
quantum well (QW) structures by post-growth thermal annealing. Ex. 1025,
36. Lin grew the quantum well sample used in its study with a low-pressure
metal-organic chemical-vapor deposition reactor. Ex. 1025, 36. The
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InGaN/GaN quantum well sample consisted of ten periods of InGaN wells,
and the quantum well layers were positioned between a GaN buffer layer
formed on a sapphire substrate and a GaN cap layer. Ex. 1025, 36. Lin
subjected the samples to thermal annealing at different temperatures and
used high-resolution transmission electron microscopy (HRTEM) and
energy filter transmission electron microscopy (EFTEM) to characterize the
material properties of test samples. Ex. 1025, 36.
Lin observed the formation of sphere-like, indium-rich quantum dots
after annealing. Ex. 1025, 37. In particular, Lin observed quantum dots
“with [a] size of 2–5 nm were regularly distributed within the designated
InGaN QW layers after annealing treatment at 900° C.” Ex. 1025, 37. Lin
provided results from EFTEM observation of the samples annealed at
900° C in Figure 2, reproduced below.

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Figure 2 of Lin provides indium map and indium composition profiles
along and across the quantum well layers of the sample after annealing at
900 degrees C. Ex. 1025, 37–38. Lin states that these figures show
“[r]egularly arrayed QDs with nearly the same indium concentration at the
cores of the QDs.” Ex. 1025, 37.
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2. Gerthsen (Ex. 1026)
Gerthsen describes an investigation of the structural properties and
composition of InGaN quantum wells embedded in Ga(Al)N barriers.
Ex. 1026, 1668. Gerthsen used HRTEM to investigate a variety of samples
produced by molecular beam epitaxy and metal-organic vapor phase epitaxy.
Ex. 1026, 1668. According to Gerthsen, “[t]he effect of the deposition
temperature, growth rate, strain and high-temperature annealing treatments
on the average In concentration and In distribution was studied to assess the
influence of phase separation, In surface segregation, and In desorption.”
Ex. 1026, 1668.
Gerthsen shows the results of the analysis of an InGaN/GaN quantum
well structure in Figure 4, reproduced below.

Figure 4 shows a color-coded map of the indium distribution in the
InGaN/GaN multiple quantum well structure and the average indium
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concentration along the horizontal direction of the wells. Ex. 1026, 1673.
Gerthsen observed a “strongly inhomogeneous In distribution in all QWs,”
including “small In-rich clusters with lateral extensions below 4 nm, which
are present at an extremely high density.” Ex. 1026, 1673–1674.
3. Schley (Ex. 1055)
Schley describes a study of the optical properties of InGaN alloy films
using spectroscopic ellipsometry. Ex. 1055, 205204-1. As part of its study,
Schley provides the following equation that allows for the calculation of
bandgap energy (ECP) as a function of composition:

Ex. 1055, 205204-5. In this equation, b is a bowing parameter, ECP,InN is the
bandgap energy for pure InN, ECP,GaN is the bandgap energy for pure GaN,
and x is the indium concentration from the expression InxGa1-xN. Ex. 1055,
205204-5.
4. Lin II (Ex. 1016)
Lin II notes that “[i]n many articles, it was proposed that nanoscale
indium composition fluctuations, due to indium aggregation of phase
separation, acted as quantum dots (QDs) in optical characteristics.”
Ex. 1016, 2988. Lin II explains that “[i]n the QDs, carriers are deeply
localized and their migration toward nonradiative defects (dislocations) is
hindered. Therefore, high-luminescence efficiency is expected if the density
of QDs is much higher than that of dislocations.” Ex. 1016, 2988. In view
of this, Lin II describes a study of the effects of nominal indium content on
the composition fluctuation/QD formation and structural defects in
InGaN/GaN multiple quantum wells. Ex. 1016, 2988.
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D. Claims 1, 4–7, 10, 11, and 17–19 — Alleged Anticipation by Lin
Petitioner contends Lin anticipates claims 1, 4–7, 10, 11, and 17–19.
Pet. 26–41. Petitioner relies on declarations from Dr. Dupuis (Ex. 1002
(“First Declaration”) and Ex. 1071 (“Second Declaration”)) and Dr. Ponce
(Ex. 1066) to support its arguments.
1. Claim 1
Independent claim 1 of the ’225 patent recites a light emitting device
comprising a substrate, a first semiconductor layer on the substrate, a second
semiconductor layer on the first semiconductor layer, and multi-quantum
well structure comprising at least one well layer and one barrier layer
between the first and second semiconductor layers. For these limitations,
Petitioner directs us to Lin’s disclosure of an “InGaN/GaN QW sample
consist[ing] of ten periods of InGaN wells,” wherein the quantum well
layers “were sandwiched between a 1.5 µm GaN buffer layer on a (0 0 0 1)
sapphire substrate and a 50 nm GaN cap layer.” Ex. 1025, 36; Pet. 27–28.
According to Petitioner, the “(0 0 0 1) sapphire substrate” in Lin corresponds
to the claimed substrate, the “1.5 µm GaN buffer layer” corresponds to the
claimed first semiconductor layer, the “50 nm GaN cap layer” corresponds
to the second semiconductor layer, and the InGaN/GaN quantum wells
sandwiched between the layers correspond to the claimed multi-quantum
well structure. Pet. 27–28.
Claim 1 of the ’225 patent further requires “at least one layer within
the multi-quantum well structure comprising at least one carrier trap portion
formed therein.” Ex. 1001, 6:50–52. Petitioner contends that Lin’s InGaN
well layers include indium-rich quantum clusters that become sphere-like
shaped after annealing. Pet. 28–29 (citing Ex. 1025, 36–37). Petitioner
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directs us to Lin’s HRTEM images of its samples, and Lin’s statement that
“one can observe that fine indium-rich QDs with size 2–5 nm were regularly
distributed within the designated InGaN QW layers.” Pet. 28–29 (quoting
Ex. 1025, 37). According to Petitioner, “[t]his regular distribution of
quantum dots within the InGaN well layer describes a number of ‘carrier
trap portions’ within the layer.” Pet. 29 (citing Ex. 1002 ¶¶ 89–90).
Patent Owner does not dispute that Lin’s quantum dots correspond to
the carrier trap portions recited in claim 1. See, e.g., PO Resp. 24, 31–33.
The parties’ positions are consistent with Lin’s introductory disclosure that
“[i]ndium-rich clusters near InGaN quantum well (QW) layers in an
InGaN/GaN QW structure are closely related to the photon emission
efficiency of such a compound. . . . The localized energy states formed at
these clusters can trap carriers for photon emission and reduce non-radiative
recombination rate.” Ex. 1025, 35 (citation omitted).
Claim 1 next recites “the at least one carrier trap portion having a
band-gap energy decreasing from a periphery of the carrier trap portion to a
center of the carrier trap portion.” Ex. 1001, 6:52–55 (referred to herein as
the “bandgap energy profile” limitation). Petitioner asserts that “Lin’s
quantum dots” satisfy this limitation and relies on the known inverse
relationship between indium concentration and bandgap energy, namely a
higher indium content means lower bandgap energy. Pet. 30–31. Petitioner
also directs us to Figure 2(d) of Lin, reproduced below. Pet. 30.
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Figure 2d shows the indium composition amplitude profile along a quantum
well layer in Lin’s sample. Ex. 1025, 38.
Petitioner argues
The distribution of indium within the indium-rich quantum dots
for the sample annealed at 900°C is shown in [Lin Figure 2(d)].
. . . As can be seen from this graph, the indium concentration
increases from one minima to a maxima and then returns to an
adjacent minima periodically. A POSA reviewing this graph
would have understood that the center of each of the quantum
dots is defined by the point with a maximum indium
composition. Ex. 1002, ¶ 92. On either side of each maxima, the
concentration of indium decreases until it hits a local minima.
Id., ¶ 91. Therefore, regardless of where the precise bounds of
carrier trap portion are defined—something that the ’225 patent
says need not have “a physical shape,” Ex. 1001, 4:42-47—a
POSA would have recognized that the indium concentration
increases from the outer periphery of the carrier trap portion to
the maxima for each quantum dot. Ex. 1002, ¶ 92; Ex. 1025,
p.38 (Fig. 2(d)).
Pet. 30–31.
Petitioner thus concludes that, “because Lin teaches that the indium
concentration increases within the carrier trap portion, Lin teaches that the
bandgap energy decreases from the periphery of the carrier trap portion to its
center.” Pet. 31–32 (citing Ex. 1002 ¶¶ 91–93).
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Patent Owner contends that Lin does not disclose how indium
concentration changes within any individual alleged carrier trap portion. PO
Resp. 21–22. Patent Owner argues Figure 2(d) of Lin, which forms the basis
of Petitioner’s anticipation argument, is derived from TEM measurements.
PO Resp. 27. According to Patent Owner, it is undisputed that TEM images
“are based on the average of what electrons experience as they travel
through the sample thickness.” PO Resp. 27, 31 (emphasis omitted) (citing
Ex. 2014, 124:18–125:16, deposition testimony from Dr. Dupuis
acknowledging that Lin’s measurements in Figure 2(d) are “clearly . . . an
average of the scan”). Patent Owner asserts that Lin describes its QDs as
regularly distributed within the quantum well layers, and having a size
between 2–5 nm. PO Resp. 28 (citing Ex. 1025, 37). Patent Owner
contends that because Lin discloses nothing about the thickness of the
sample used to generate the data in Lin Figure 2(d), it is “it is impossible to
know how many ‘QDs with size 2-5 nm’ electrons encountered as they
traveled through the sample thickness.” PO Resp. 32 (quoting Ex. 1025, 37;
citing Ex. 2016 ¶132; Ex. 2014, 127:11–17); see also PO Resp. 31–32
(arguing it is “impossible to know how many QDs (or portions thereof) were
encountered by the electrons that traveled through the sample to yield Figure
2(d)”); PO Resp. 24–25 (emphasis omitted) (contending that Lin discloses
“indium distributions averaged through the sample thickness, which includes
an unknown number of indium-rich QDs (or portions thereof) and relatively
indium-poor regions around them”).
Patent Owner thus argues that the averaged TEM measurements
reported in Lin Figure 2(d) “cannot be attributed to any particular QD.” PO
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Resp. 27.7 In this regard, Patent Owner directs us to testimony from
Petitioner’s declarant, Dr. Dupuis, indicating that the regions inside Lin’s
quantum dots are “not directly imageable.” PO Resp. 31 (quoting Ex. 2014,
126:10–21). Accordingly, Patent Owner argues that “[t]here is simply no
way to determine how indium is distributed within any QDs from Lin’s
Figure 2(d).” PO Resp. 32.
After considering both parties’ arguments and evidence, we determine
that Petitioner has not met its burden of proof to show that Lin discloses the
bandgap energy profile limitation of claim 1. We recognize that the ’225
patent indicates that the claimed carrier trap portion is “not limited to a
physical shape.” Ex. 1001, 4:40–43. Petitioner, however, argues Lin’s
quantum dots correspond to the claimed carrier trap portions. Pet. 28–29.
Accordingly, the relevant inquiry for purposes of anticipation is whether
Petitioner has shown that Lin’s quantum dots have the bandgap energy
profile recited in claim 1.
We are persuaded by Patent Owner’s arguments that the TEM data
presented in Lin Figure 2(d) cannot be attributed to any particular quantum
dot in Lin, and, therefore, does not constitute evidence sufficient to support

7 Patent Owner also presents illustrations and hypothetical examples to
explain why TEM measurements do not necessarily reveal granular
information about local regions within a sample, and, therefore, it is
improper to interpret TEM measurements as showing the indium
concentration inside a single quantum dot. PO Resp. 25–27, 34–38.
Petitioner contends that Patent Owner relies on these hypotheticals to
“attack” Lin’s conclusions. Reply 17. We disagree. Patent Owner relies on
these hypotheticals to show the limitations of TEM measurements and the
reasons why Petitioner’s attempt to draw a conclusion regarding the
composition profile within Lin’s quantum dots from TEM’s averaged
measurements is flawed.
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Petitioner’s contention that “Lin’s quantum dots” (Pet. 30) satisfy the
bandgap energy profile limitation in claim 1. Declarants from both parties
agree that TEM measurements report an average indium composition over
the thickness of the sample. Ex. 2016 (Doolittle Decl.) ¶ 132; Ex. 2014
(Dupuis Deposition Tr.), 17:7–13; 124:18–125:22, 126:10–21; Ex. 2019
(Ponce Deposition Tr.), 41:3–14. Lin states its quantum dots range in size
between 2–5 nm, and, it is undisputed that Lin does not disclose the
thickness of its sample. Ex. 1025, 37; Ex. 2014: 127:11–17; Ex. 2016 ¶ 132.
We thus agree with Patent Owner that “it is impossible to know how many
‘QDs with size 2-5 nm’ electrons encountered as they traveled through the
sample thickness.” PO Resp. 32.
In view of Dr. Dupuis’ deposition testimony (e.g., Ex. 2014,
124:18–125:22, referring to “an average of the scan”), we do not credit his
declaration testimony that Lin Figure 2(d) shows the “distribution of indium
within the indium-rich quantum dots,” wherein “the center of each of the
quantum dots is defined by the point with a maximum indium composition.”
Ex. 1002 ¶¶ 91–92 (emphasis added). Because we do not find this testimony
from Dr. Dupuis’ declaration to be credible, there is insufficient basis for
Petitioner’s argument that Lin discloses “at least one carrier trap portion
having a band-gap energy decreasing from a periphery of the carrier trap
portion to a center of the carrier trap portion.” Pet. 30–31.
In its Reply, Petitioner maintains that it has provided evidence that
Lin’s “quantum dots” have the bandgap energy profile recited in claim 1.
Reply 16–23. Petitioner, however, appears to shift from its original position
in the Petition that Figure 2(d) shows the “distribution of indium within the
indium-rich quantum dots.” Pet. 30 (emphasis added). Instead, Petitioner
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acknowledges in the Reply that Figure 2(d) “shows variations in indium
content within an InGaN well layer.” Reply 20 (emphasis added); see also
Reply 1 (Petitioner noting that Lin “describes well layers with periodically
varying indium content” (emphasis added)). Petitioner also states that
“Lin’s . . . conclusions do not rest solely on TEM” (Reply 19) and Lin’s
analysis, “including the TEM images” provides a “reliable indication[ ] of
changes in indium composition within QDs” (Reply 23). Petitioner’s Reply
includes arguments based on the natural behavior of indium clusters, the
assertion that “InGaN exhibits complex growth processes,” and evidence
purporting to establish that InGaN quantum wells naturally have a variation
in indium composition. Reply 17–22 (citing Ex. 1071 ¶¶ 12–15; Ex. 1066
¶¶ 27, 58, 61); Tr. 19:14–20:4 (referring to “how indium behaves”).
Patent Owner argues Petitioner raises new arguments in its Reply that
we should not consider, citing the Federal Circuit’s holding in Wasica Fin.
GmbH v. Cont’l Auto. Sys. Inc., 853 F.3d 1272, 1286 (Fed. Cir. 2017), that a
petitioner cannot “cure the petition’s deficiencies in its subsequent briefing.”
Sur-reply 4. We find this argument persuasive.
As discussed above, in the Petition, Petitioner argued Figure 2(d)
shows Lin’s quantum dots have an indium composition that varies from its
periphery to its core. Pet. 30–31. In its Patent Owner Response, Patent
Owner presented undisputed evidence that TEM measurements provide an
average value over the thickness of a sample, demonstrating a flaw in
Petitioner’s argument. PO Resp. 24–39. Rather than explaining why its
original argument in the Petition was correct, e.g., that Patent Owner’s
criticism of TEM was wrong and/or that the TEM data presented in Lin
Figure 2(d) can be attributed to a particular quantum dot in Lin, Petitioner
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shifted its argument and improperly relied on new evidence that was absent
from the Petition.
For example, in the Reply, in addition to Figure 2(d), Petitioner relies
on Lin’s x-ray diffraction (XRD) experiments (Reply 21–22) and contends
that InGaN’s “complex growth processes” (Reply 17) as well as “the
understanding that indium-rich clusters allowed InGaN LEDs to be highly
luminescent despite their high levels of dislocations” (Reply 19) support its
conclusion that a person of ordinary skill in the art “would have understood
that Lin[’s] . . . indium composition measurements represent changes in
bandgap energy that meet the claims” (Reply 18–19). We discern no
reference to or meaningful discussion of XRD in the Petition or Dr. Dupuis’
First Declaration (Ex. 1002). Nor do these documents contain any
meaningful discussion of the behavior of indium or the InGaN growth
process. Instead, these topics appear for the first time in Dr. Dupuis’ Second
Declaration and Dr. Ponce’s Declaration, both filed in support of Petitioner’s
Reply. See, e.g., Ex. 1071 ¶ 12 (referring to “the way that the InGaN alloys
were understood to behave”); ¶¶ 14–15 (discussing Lin’s XRD
measurements); Ex. 1066 ¶ 61 (referring to “the physics of the InGaN lattice
structure and its formation”). Petitioner thus did not rely on this evidence to
support anticipation in the Petition. See Intelligent Bio-Sys., Inc. v. Illumina
Cambridge Ltd., 821 F.3d 1359, 1369 (Fed. Cir. 2016) (“Illumina”).
In Wasica, the Federal Circuit stated that “[i]t is of the utmost
importance that petitioners in the IPR proceedings adhere to the requirement
that the initial petition identify with particularity the evidence that supports
the grounds for the challenge to each claim.” Wasica, 853 F. 3d at 1286
(quoting Illumina, 821 F.3d at 1369). Similar to the petitioner in Wasica,
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instead of relying on the evidence and arguments presented in the Petition,
namely that Figure 2(d) shows Lin’s quantum dots have the required
bandgap properties, Petitioner directs us, in the Reply, to a different portion
of Lin (e.g., Figure 4 and the corresponding discussion of Lin’s XRD data)
along with other new evidence regarding the natural behavior of InGaN
alloys during the growth of InGaN (e.g., Ex. 1071 ¶¶ 12–15; Ex. 1066 ¶ 61),
and shifts its position to argue that it’s evidence “including the TEM
images” in Lin Figure 2(d) demonstrates a person of ordinary skill in the art
would have understood Lin discloses carrier trap portions having the
required bandgap energy profile. Reply 16–22; Wasica, 853 F.3d at 1286.
As the Federal Circuit found in Wasica, Petitioner’s actions reveal an
attempt to cure the deficiencies in the Petition, and are “foreclosed by
statute, [Federal Circuit] precedent, and Board guidelines.” Wasica, 853
F.3d at 1286–87 (citing Illumina, 821 F.3d at 1369–70, 35 U.S.C.
§ 312(a)(3), and the Board’s Trial Practice Guide, 77 Fed. Reg. 48,756,
48,767 (Aug. 14, 2012)8).
Under these circumstances the Federal Circuit has indicated that we
may decline to consider Petitioner’s new arguments and evidence. Id. at
1287. Doing so here results in weighing Petitioner’s reliance on Lin
Figure 2(d) as the basis for its argument that Lin discloses a carrier trap
portion having the required bandgap energy profile against Patent Owner’s
largely undisputed evidence that the TEM data presented in Lin Figure 2(d)
cannot be attributed to any particular quantum dot in Lin. For the reasons

8 Our Consolidated Trial Practice Guide (“CTPG,” available at
https://www.uspto.gov/TrialPracticeGuideConsolidated), issued November
2019, contains similar guidelines. CTPG, 73.
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discussed above, namely the inability to attribute the indium composition
variation in Figure 2(d) to a particular quantum dot in Lin, the evidence
Petitioner presents in the Petition is not sufficient to support Petitioner’s
contention that “Lin’s quantum dots” satisfy the bandgap energy profile
limitation in claim 1.
Nor are we persuaded by Petitioner’s argument in the Reply that
Patent Owner’s declarant, Dr. Doolittle, admitted that the bandgap energy in
InGaN quantum dots or carrier traps is not constant. Reply 16–17. To
arrive at this purported admission, Petitioner pieces together answers from
different questions during the deposition of Dr. Doolittle. Reply 16–17.
Notably, Petitioner relies upon Dr. Doolittle’s testimony that there are “other
materials . . . that have substantially flatter quantum wells than perhaps in
the indium gallium nitride case.” Reply 17 (quoting Ex. 1064, 93:10–22).
During the deposition, however, counsel for Petitioner noted that Dr.
Doolittle’s answer referred to quantum wells, not carrier traps. Ex. 1064,
93:23–25. After clarifying that point, counsel for Petitioner asked the same
question again, and Dr. Doolittle provided a different answer. Ex. 1064,
93:23–94:20. Furthermore, as Patent Owner points out, Dr. Doolittle
testified that “it is possible to grow . . . quantum well structures that are
abrupt and have a flat region inside what would be then a portion of the
material that could capture carriers.” Ex. 1064, 96:16–21; Sur-reply 6.
Nevertheless, even if Dr. Doolittle’s testimony does amount to an
admission that the bandgap energy in InGaN quantum dots or carrier trap
portions is not constant, such an admission does not demonstrate that InGaN
quantum dots have the specific bandgap energy profile required in claim 1.
The burden of proving Lin discloses a quantum dot having a bandgap energy
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that decreases from its periphery to its center remains with Petitioner, and an
admission that the bandgap energy in InGaN quantum dots is not constant
does not satisfy that burden.
For all of the foregoing reasons, we find Petitioner has failed to
demonstrate sufficiently that Lin discloses all limitations in claim 1, and,
therefore, has not demonstrated by a preponderance of evidence that Lin
anticipates claim 1.
While we decline to consider Petitioner’s new evidence and
arguments that go beyond Lin Figure 2(b) because Petitioner presented them
for the first time in the Reply, we further note that the outcome here would
not change even if we were to consider the merits of the new arguments and
evidence. For example, Petitioner directs us to several portions of Lin in
support of its Reply arguments. Reply 19–20. We agree with Petitioner that
Lin teaches that indium-rich clusters “can trap carriers for photon emission
and reduce non-radiative recombination rate.” Ex. 1025, 35; Reply 19. Lin
also teaches that post-growth annealing “led to better confinement of
indium-rich clusters,” “[t]he QDs become sphere-like shaped and their
average size becomes smaller after annealing treatment,” and “[t]he
originally shaped cluster boundaries became sharpened after post-growth
thermal annealing.” Ex. 1025, 37; Reply 19. Lin also states that it
performed EFTEM measurements “[t]o further understand the composition
variation” in the InGaN QW structure, and “[i]ndium map and indium
composition profiles along and across QW layers of the sample after 900°C
annealing are shown in Figure 2.” Ex. 1025, 37; Reply 19–20. Lin reports
that, based on the EFTEM measurements, it observed “[r]egularly arrayed
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QDs with nearly the same indium concentration at the cores of the QDs.”
Ex. 1025, 37.
None of these statements in Lin, however, demonstrate sufficiently
that Lin discloses quantum dots having the bandgap energy profile recited in
the claims. At best, these statements demonstrate that Lin understood
quantum dots can trap carriers, and that Lin was able to grow an InGaN
quantum well structure having quantum dots that are sphere-like in shape,
have nearly the same indium content at their cores, and form sharper
boundaries after annealing. Ex. 1025, 37. These statements also
demonstrate Lin used TEM to map indium composition across and along
quantum well layers and provided an indium composition amplitude profile
along a QW in Figure 2(d). Ex. 1025, 37–38.
Referring to Figure 2(d), Petitioner argues that “Patent Owner cannot
credibly deny that Lin shows local variations of indium through the cross-
section of the sample.” Reply 20 (emphasis added). According to
Petitioner, “Patent Owner’s expert agrees that on average the region shown
at 5 nm in Lin’s Figure 2(d) and the region shown at 10 nm have a different
indium composition.” Id. (emphasis added; citing Ex. 1064, 88:8–89:9). As
discussed above, however, averages across an unknown sample thickness are
not sufficient to show a variation within the 2–5 nm sphere-like quantum
dots Petitioner identifies as the carrier traps in Lin. We are persuaded by
Patent Owner’s argument that the nature of TEM measurement, namely
averaging indium concentration through the sample thickness, means the
data from Figure 2(d) cannot be attributed to any particular quantum dot.
E.g., PO Resp. 39.
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Petitioner’s argument that the indium is not uniformly distributed
through the sample because InGaN creates “clusters which act to confine the
carriers and prevent non-radiative recombination,” as opposed to “neat
quantum wires,” is unavailing. Reply 20 (citing Ex. 1071 ¶¶ 12–13).
Petitioner admits that it is not asserting an inherency argument – so the fact
that InGaN forms clusters that confine carriers, i.e., carrier trap portions,
does not constitute evidence sufficient to demonstrate that Lin’s carrier trap
portions have the required bandgap energy profile for purposes of
anticipation. See Tr. 27:1–10; 42:16–17. The relevant inquiry here is not
whether Lin discloses clusters that confine carriers, but whether Petitioner
has shown, by a preponderance of evidence, that Lin’s carrier trap portions
(i.e., its quantum dots) have the specific bandgap energy profile recited in
claim 1. See Pet. 30 (Petitioner arguing “Lin’s quantum dots have a band-
gap energy that decreases from a periphery of the quantum dot (where the
concentration of indium is lower) to the center of the quantum dot (where
the concentration of indium is higher)”). A “periodic arrangement of indium
rich regions” in an InGaN well layer (Reply 20) is not sufficient to meet the
bandgap energy profile limitation, which requires Petitioner to show a
bandgap energy gradient within the carrier trap portions (i.e., Lin’s quantum
dots).
Petitioner next directs us to Lin’s XRD experiments. Reply 21.
Referring to Figure 4b of Lin, Petitioner contends Lin’s XRD data shows
pronounced peaks for InN and GaN, and “subtle peaks . . . in the angular
range for InGaN.” Reply 21. Petitioner presents an annotated version of Lin
Figure 4(b) with red arrows indicating the purported InGaN peaks.
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Figure 4(b) of Lin shows XRD spectra of Lin’s sample annealed at 900°C.
Ex. 1025, 39.
Dr. Dupuis states that Lin’s XRD measurements “show that there is a
gradual change in the indium composition within the InGaN QWs.”
Ex. 1071 ¶ 14. Dr. Dupuis’ opinion is based on a comparison between
Figure 4 in Lin and “similar XRD scans of other InGaN/GaN MQW
samples” from Lin II (Ex. 1016), a 2000 article written by Lin. Ex. 1071
¶ 14. Dr. Dupuis testifies that Lin Figures 4(a) and (b) show peaks for InN
and GaN, along with “some shoulders and lower-intensity XRD signals.”
Ex. 1071 ¶ 14. Dr. Dupuis states that the XRD scans in Lin II show peaks
for GaN and InN, as well as a distinct peak that “indicates the existence of a
distinct local ‘region’ of InGaN ternary alloy material” corresponding to
In0.09Ga0.91N material, which is not the intended In0.20Ga0.80N alloy
composition. Ex. 1071 ¶ 14. Again referring to Lin II’s XRD scans,
Dr. Dupuis identifies “a shoulder” due to a region having a graded InxGa1-xN
alloy composition. Ex. 1071 ¶ 14.
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From the XRD data in Lin II (Ex. 1016), Dr. Dupuis concludes that
“there has been spinodal decomposition taking place in the InGaN layers
during the growth of this MQW region and the InxGa1-xN QWs, intended to
be pure In0.20Ga0.80N, have decomposed during MOCVD growth into InN
regions, In0.09Ga0.91N regions, and InxGa1-xN regions having a graded In alloy
composition.” Ex. 1071 ¶ 14. Dr. Dupuis then testifies that, similar to the
decomposition observed in the samples in Lin II, Lin’s XRD spectra in
Figure 4(b) shows “very subtle ripples” that suggest a
high degree of decomposition has occurred during MQW growth
such that instead of QWs having a constant InxGa1-xN alloy
composition, there are regions of InN—that would have a
relatively smaller energy gap—and InxGa1-xN regions having
relatively larger energy gap, and a gradual variation in the alloy
composition of InxGa1-xN between the GaN material in the barrier
and the localized InN regions in the QWs.
Ex. 1071 ¶ 15. According to Dr. Dupuis, a structure with this type of
gradual variation in indium composition “would, necessarily, have quantum
states in the MQW region defined by the smaller-bandgap InN regions and
the larger-bandgap graded-composition InxGa1-xN regions that surround
these InN regions.” Ex. 1071 ¶ 15.
Based on Dr. Dupuis’ testimony, Petitioner argues that
In comparison to [Lin II], the absence of defined peaks of InGaN
shows that there are few defined regions of a specific indium
composition within the InGaN. Ex. 1071, ¶ 15. Instead, the
XRD simulation is consistent with a curved bandgap profile for
the QDs as they approach an InN phase region.
Reply 21–22. Petitioner also contends that the XRD data confirms Lin’s
“conclu[sion] that by annealing, indium diffused in an ‘uphill manner,’ i.e.,
‘diffusion in the opposite direction of the composition gradient,’ thus
producing a ‘stronger InN peak and sharper interfaces between InN and
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surrounding matrix.’” Reply 22 (quoting Ex. 1025, 38 and citing Ex. 1071 ¶
15).
Patent Owner argues this evidence does not support a conclusion that
Lin’s quantum dots have the claimed bandgap energy profile because it
“reveals nothing about how, if at all, the indium distribution changes within
any QD.” Sur-reply 8. We agree with Patent Owner.
First, Dr. Dupuis’ conclusions regarding the distribution of indium in
the sample in Lin Figure 4 are based largely on XRD data in Lin II, which
was generated from different samples in a different study conducted by Lin.
Ex. 1071 ¶¶ 14–15 (discussing XRD data in Lin and Lin II), ¶ 16 (stating
that the decomposition that occurs in the sample in Lin Figure 4 is “similar
to the InGaN decomposition Lin describes in his earlier paper, Ex. 1016”).
The XRD scans in Lin II (Ex. 1016), however, are noticeably different than
those in Lin Figure 4. For example, as Dr. Dupuis discusses, Figure 1(b) in
Lin II contains a distinct peak that “indicates the existence of a distinct local
‘region’ of InGaN ternary alloy material of a specific alloy composition.”
Ex. 1071 ¶ 14 (referring to the peak labeled (C) in Figure 1 of Ex. 1016).
No such distinct peak for an InGaN ternary alloy material appears in Lin
Figure 4. Ex. 1025, 39. Additionally, the InN peak in Lin II (designated (A)
in Figure 1(b)) is significantly smaller than the InN peak in Lin Figure 4.
Compare Ex. 1025, 38 (Figure 4(b)) with Ex. 1016, 2989 (Figure 1(b)).
Nevertheless, Petitioner and Dr. Dupuis assert that the sample in Lin
Figure 4 would decompose during growth just as the samples in Lin II
Figure 1(b) did, to also produce InN regions and InxGa1-xN regions having a
graded In alloy composition. Ex. 1071 ¶¶ 15–16; Reply 21–22. The
differences in the XRD scans between the samples in Lin Figure 4 and Lin II
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(Ex. 1016), and the failure of Petitioner and Dr. Dupuis to account for these
differences, diminishes the weight we are willing to assign to Dr. Dupuis’
opinion. See 37 C.F.R. § 42.65 (a).
Setting the aforementioned deficiency aside, and assuming that
Petitioner and Dr. Dupuis are correct that the XRD data shows the sample in
Lin Figure 4(b) has a “graded InxGa1-xN alloy composition,” we remain
unpersuaded by Petitioner’s argument. Dr. Dupuis and Dr. Ponce
acknowledge that the XRD data in Lin provides no information about where
in the sample certain material is located. Ex. 2019, 95:14–16; Ex. 2020,
146:17–20; Sur-reply 9 n.4. Thus, it is impossible to tell from the XRD data
exactly where in the sample the purported graded alloy composition is
present, and likewise impossible to conclude that the sample “would,
necessarily, have quantum states in the MQW region defined by the smaller-
bandgap InN regions and the larger-bandgap graded-composition InxGa1-xN
regions that surround these InN regions.” Ex. 1071 ¶ 15 (emphasis added).
Indeed, Dr. Dupuis testified “the features of InGaN aren’t revealed in [Lin’s
Figure 4 XRD] data.” Ex. 2014, 117:6–7. Thus, we are not persuaded that
Lin’s XRD data, even when considered with the average indium distribution
shown Figure 2(d), provides sufficient evidence regarding the indium
distribution within Lin’s quantum dots.
Nor are we persuaded by Petitioner’s reliance on Lin’s disclosure that
“[p]ost growth thermal annealing facilitates indium-rich phase to grow
gradually . . . via the ‘uphill’ diffusion mechanism, i.e., diffusion in the
opposite direction to the composition gradient.” Ex. 1025, 38; Reply 22.
Lin’s statement that indium moves from areas of low indium concentration
to areas of high indium concentration during growth does not provide
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sufficient information about where there areas of low indium concentration
exist within the sample in relation to Lin’s quantum dots. As a result, we are
not persuaded Lin’s description of the general movement of indium provides
information about how, if at all, the indium composition varies within any
quantum dot.
Petitioner also relies on Dr. Ponce’s testimony that Lin’s results
“clearly indicate that compositional inhomogeneities exist in as-grown
InGaN QWs.” Ex. 1066 ¶ 60; Reply 22. According to Dr. Ponce, Lin
attributes the formation of QDs to “clustering of indium atoms along the
[0001] direction and anti-clustering of indium atoms in the (0001) plane . . .
due to dipole interaction energy.” Ex. 1066 ¶ 60. Referring to “the physics
of the InGaN lattice structure and its formation,” Dr. Ponce states that “[t]he
only reasonable conclusion from the data shown in Lin’s Fig. 2 is that the
bandgap” of Lin’s carrier trap portions “is not constant, and that it shows
indium-rich clusters in the quantum wells that due the ‘anti-clustering of
indium atoms in the (0001) plane’ have bandgap energies that decrease from
a periphery of the indium cluster towards the center of the cluster.”
Ex. 1066 ¶ 61.
Dr. Ponce, however, does not explain sufficiently what “anti-
clustering of indium atoms in the (0001) plane” means or how it allows a
person of ordinary skill in the art to conclude that the bandgap energy of
Lin’s carrier trap portions decrease from a periphery of the indium cluster to
the center of the cluster.9 Further, even if Dr. Ponce is correct that the

9 Additionally, Lin states that the formation of sphere-like quantum dots may
arise from a second mechanism—“a disk-like island with a small
height/width ratio is practically non-relaxed.” Ex. 1025, 37. Dr. Ponce does
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physics of the InGaN lattice structure and its formation lead to
“compositional variations” in InGaN quantum wells, the existence of such
variations alone is not sufficient to demonstrate that Lin’s quantum dots
have the bandgap energy profile required in claim 1. For example,
Dr. Ponce does not provide information about the location of any
compositional variation in Lin’s quantum wells such that a person of
ordinary skill in the art would be able to determine the indium distribution
within Lin’s quantum dots. As Patent Owner points out, Dr. Ponce
acknowledges that “Lin is not claiming to provide a distribution of indium
within the indium-rich clusters.” Sur-reply 4 (emphasis omitted); Ex. 2019,
112:8–21. Accordingly, we are not persuaded that Dr. Ponce has adequately
supported his opinion that “[t]he only reasonable conclusion from the data
shown in Lin’s Fig. 2” is that Lin’s carrier trap portions “have bandgap
energies that decrease from a periphery of the indium cluster towards the
center of the cluster.” Ex. 1066 ¶ 61.
Although Petitioner maps Lin’s quantum dots to the carrier trap
portion recited in claim 1 in its Petition, in its Reply Petitioner attempts to
rely on the purported composition gradient in the matrix surrounding Lin’s
quantum dots as evidence that Lin’s quantum dots have the bandgap energy
profile recited in claim 1. Pet. 30–31; Reply 16–22. As Patent Owner points
out, the evidence of a composition gradient in the matrix is not evidence of
indium composition within the quantum dot itself. Sur-reply 4. For
example, Petitioner’s evidence regarding the presence of a composition

not address this mechanism or explain how it may impact his conclusions
that appear to be based only on the first mechanism Lin describes, which
involves the anti-clustering effect Dr. Ponce discusses.
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gradient in Lin’s quantum wells is based on XRD data that does not provide
information regarding the location of the components within a sample.
Ex. 2019, 95:14–17; Ex. 2020, 146:17–20. Petitioner’s evidence regarding
the natural behavior of indium during growth suffers from the same
deficiency. Thus, the evidence does not demonstrate the presence of a
composition gradient in a location sufficient to identify a carrier trap portion
having the bandgap energy profile requirement in claim 1.
For all of the foregoing reasons, we find Petitioner has failed to
demonstrate, by a preponderance of evidence, that Lin discloses a carrier
trap portion having the bandgap energy profile claim 1 requires, and
therefore, anticipates claim 1.
2. Claims 4–7, 10, 11, and 17–19
Claims 4–7, 10, 11, and 17–19 depend directly or indirectly from
claim 1, and therefore contain all the limitations of claim 1. In its analysis of
these dependent claims, Petitioner does not present any additional
information regarding Lin’s disclosure of carrier trap portions having the
bandgap energy profile recited in claim 1. Pet. 32–41. Thus, for the same
reasons discussed above in connection with claim 1, we determine Petitioner
has failed to establish sufficiently that Lin teaches each limitation of claims
4–7, 10, 11, and 17–19. In view of this, we determine Petitioner has failed
to demonstrate, by a preponderance of evidence, that Lin anticipates claims
4–7, 10, 11, and 17–19 of the ’225 patent.
E. Obviousness Challenges Based on Lin
Petitioner argues dependent claim 4 is unpatentable as obvious in
view of the combined teachings of Lin and Schley (Pet. 42–44) and
dependent claim 16 is unpatentable as obvious in view of the combined
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teachings of Lin and Lin II (Pet. 44–45). Claims 4 and 16 depend from
claim 1, and therefore contain all of the limitations in claim 1. Petitioner
does not rely on Schley or Lin II to cure the deficiencies discussed above
regarding Petitioner’s assertion that Lin discloses all of the limitations in
claim 1. Pet. 42–45. As a result, for the same reasons discussed above, we
determine Petitioner has failed to demonstrate, by a preponderance of
evidence, that claim 4 is unpatentable as obvious in view of Lin and Schley,
or that claim 16 is unpatentable as obvious in view of Lin and Lin II.
F. Claims 1, 5–7, 10, 11, 15, and 17–19 — Alleged Anticipation by
Gerthsen
Petitioner contends Gerthsen anticipates claims 1, 5–7, 10, 11, 15, and
17–19. Pet. 46–56. Petitioner directs us to portions of Gerthsen that
purportedly disclose all the limitations of the challenged claims, and also
relies on declarations from Dr. Dupuis and Dr. Ponce to support its
arguments.
1. Claim 1
Independent claim 1 of the ’225 patent recites a light emitting device
comprising a substrate, a first semiconductor layer on the substrate, a second
semiconductor layer on the first semiconductor layer, and a multi-quantum
well structure comprising at least one well layer and one barrier layer
between the first and second semiconductor layers. For these limitations,
Petitioner directs us to Gerthsen’s disclosure of an “InGaN/GaN QW
structure, which contains 5 InGaN layers separated by 5 nm GaN spacers . . .
grown on a SiC(0001) substrate on Si-doped 380 nm AlGaN and 75 nm
GaN buffer layers,” and “capped by 75 nm GaN and 240 nm AlGaN doped
with Mg.” Ex. 1026, 1673; Pet. 46–47. According to Petitioner, the
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“SiC(0001) substrate” in Gerthsen corresponds to the claimed substrate, the
“Si-doped 380 nm AlGaN” corresponds to the claimed first semiconductor
layer, the “240 nm AlGaN doped with Mg” corresponds to the second
semiconductor layer, and the InGaN/GaN quantum well structure
corresponds to the claimed multi-quantum well structure. Pet. 46–47
(emphasis omitted).
Claim 1 of the ’225 patent further requires “at least one layer within
the multi-quantum well structure comprising at least one carrier trap portion
formed therein, the at least one carrier trap portion having a band-gap energy
decreasing from a periphery of the carrier trap portion to a center of the
carrier trap portion.” Ex. 1001, 6:48–55.
Petitioner directs us to Gerthsen’s statement that “composition
fluctuations are always present in InGaN. In particular, In-rich agglomerates
with sizes of only a few nm are a characteristic feature, which are often
suggested to act optically as quantum dots.” Pet. 47–48; Ex. 1026, 1669.
According to Petitioner, a person of ordinary skill in the art “would have
recognized that indium-rich quantum dots are carrier traps because an
increase in indium reduces the bandgap energy to create localized states.”
Pet. 48 (citing Ex. 1002 ¶¶ 33, 40, 46, 103; Ex. 1016, 2988).
Petitioner further argues that Gerthsen’s carrier trap portions have a
band-gap energy decreasing from a periphery of the carrier trap portion to a
center of the carrier trap portion based on the information presented in
Figure 4(a) of Gerthsen, reproduced below. Pet. 49.
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Figure 4(a) shows a color coded map of the indium distribution of an
InGaN multiple-quantum well structure. Ex. 1026, 1673. Petitioner argues
that a person of ordinary skill in the art would recognize that the indium
concentration increases from the outer periphery of the carrier trap portion to
the maxima for each indium-rich quantum dot because “the indium
concentration (XIn[%]) in, for example, the bottom most well-layer of the
MQW structure is nominally at 37% and increases in regions of the quantum
dots from 48% to a concentration of greater than 60%.” Pet. 49–50 (citing
Ex. 1002 ¶ 104). In view of this, and the well-known inverse relationship
between indium concentration and bandgap energy, Petitioner argues that
Gerthsen teaches the bandgap energy of the carrier trap portion decreases
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from the outer periphery of the carrier trap portion to the center, as claim 1
requires. Pet. 50 (citing Ex. 1002 ¶ 106).
Similar to the arguments presented regarding Lin, Patent Owner
argues that Petitioner failed to demonstrate that Gerthsen discloses a carrier
trap portion having a band-gap energy decreasing from its periphery to its
center because Gerthsen obtained Figure 4(a) using HRTEM. PO Resp. 28–
29. Patent Owner contends that Gerthsen Figure 4(a) shows “average
indium distribution through the sample thickness, which includes an
unknown number of purported indium-rich QDs (and portions thereof) and
relatively indium-poor regions around them.” PO Resp. 29 (citing Ex. 2016
¶¶ 126–136; Ex. 2014, 17:7–13). Patent Owner argues that Gerthsen’s
Figure 4(a) shows average indium concentration through the sample
thickness, not actual concentration at any particular location. PO Resp. 29
(citing Ex. 1026, 1674). Patent Owner relies on Gerthsen’s statements that
Figure 4(a) shows “an apparent In concentration,” and “[t]he measured In
concentrations are an averaged value determined by the composition of the
cluster and the embedding matrix along the electron-beam direction for
HRTEM sample thicknesses.” PO Resp. 29–30 (quoting Ex. 1026, 1674
(emphasis added by Patent Owner)). Patent Owner notes that Gerthsen does
not disclose the thickness of the sample analyzed in Figure 4, stating only
that it “typically range[s] between 5 and 20 nm.” PO Resp. 31 (quoting Ex.
1026, 1674). Patent Owner also argues that Gerthsen fails to disclose
enough information about the quantum dots to know their size, noting that
Gerthsen states that the quantum dots have “lateral extensions below 4 nm,”
but does not describe their depth. PO Resp. 31; Ex. 1026 at 1673–74. In
view of this, Patent Owner argues “[i]t is impossible to determine how
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indium is distributed within any particular QD from an average indium
distribution obtained using TEM.” PO Resp. 30.
In its Reply, Petitioner contends “Gerthsen describes samples that can
be as little as a QD thick,” and that “Gerthsen studied the effect of sample
thickness and concluded its variations (from 5 nm to 20 nm) had ‘negligible
influence.’” Reply 22 (citing Ex. 1026, 1673). Based on this, Petitioner
argues that Gerthsen itself does not support a finding that “averaging
through the sample played a potential dramatic effect on Gerthsen’s
conclusions.” Reply 22 (citing Ex. 1071 ¶¶ 18–21).
Patent Owner disputes this assertion, arguing that Gerthsen’s
statement regarding the “negligible influence of the sample thickness
variation” refers to “Gerthsen’s simulation modeling use of local lattice
parameter (LLP).” Sur-reply 10–11. Patent Owner argues Gerthsen does
not present information sufficient to evaluate whether samples of different
thicknesses yield similar TEM images. Sur-reply 11 (citing Ex. 2020
(Dupuis Second Deposition Tr.), 180:10–13).
We are not persuaded by Petitioner’s arguments that Gerthsen
discloses a carrier trap portion having the bandgap energy profile recited in
claim 1. Gerthsen expressly states that Figure 4 reflects averaging over the
sample thickness. Ex. 1026, 1674. Petitioner’s declarants, Dr. Dupuis and
Dr. Ponce, do not dispute this fact. Ex. 2014, 94:13–22; Ex. 2019,
184:14–18. Gerthsen also states that Figure 4(a) shows “an apparent In
concentration” of the clusters. Ex. 1026, 1674; Sur-reply 10.
With regard to sample size, although Petitioner contends “Gerthsen
describes samples that can be as little as a QD thick,” Petitioner does not
provide support for that statement. Reply 22. Even if Petitioner had
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provided support for this statement, its relevance is limited because it
demonstrates only the size the sample could have been, not the size of the
samples actually used. Similarly, Gerthsen states only that samples
“typically range between 5 and 20 nm.” Ex. 1026, 1674.
As to the size of Gerthsen’s clusters, Gerthsen states that “In-rich
agglomerates with sizes of only a few nm are a characteristic feature,” but
Gerthsen does not provide a specific value. Ex. 1026, 1669; Ex. 1071 ¶ 17.
As Patent Owner points out, Gerthsen states that its In-rich quantum dots
have “lateral extensions below 4 nm,” but does not describe their depth. PO
Resp. 31; Ex. 1026, 1673–74. Accordingly, we agree with Patent Owner
that Gerthsen fails to disclose enough information about the quantum dots to
know their size. PO Resp. 31; Ex. 2014, 98:17–99:15 (Dr. Dupuis testifying
that “the details are not revealed” regarding Gerthsen Figure 4); 97:15–98:3
(Dr. Dupuis acknowledging that the “number of indium-rich clusters that an
electron would encounter in going through the sample to form the image
that’s shown in Figure 4 would vary, or at least could vary, depending on the
thickness of the sample”).
Furthermore, Dr. Dupuis confirmed during his deposition that
Gerthsen’s statement regarding the “negligible influence” of sample
thickness variation referred to the influence of sample thickness on the local
lattice parameters that are calculated from the model being used in a
simulation. Ex. 2020, 184:10–13. Neither Petitioner nor Dr. Dupuis explain
adequately how Gerthsen’s conclusion, derived from its calculations of LLP
from a model being used in a simulation, affects actual TEM measurements.
For example, we note that Figure 3(e), which Petitioner and Dr. Dupuis rely
on to support its assertions, plots normalized (0002) distances vs. distance in
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the [0001] direction, whereas Figure 4 plots “averaged In concentration
along the [1120] direction . . . as a function of the (0002)-plane, number.”
Ex. 1026, 1672–1673; Ex. 1071 ¶¶ 18–21. In view of the foregoing, we
agree with Patent Owner that neither Gerthsen nor Petitioner present
sufficient evidence to support a conclusion that samples of different
thicknesses yield similar TEM images. Sur-reply 10–11.
Because Gerthsen reports average values over the entire sample and
does not specify sample size or the size of the quantum dots within the
samples, it is impossible to know how many quantum dots the electrons
encountered as they traveled through Gerthsen’s sample during the TEM
analysis that generated Figure 4. Accordingly, we agree with Patent Owner
that the TEM data presented in Gerthsen Figure 4(a) cannot be attributed to
any particular quantum dot in Gerthsen. This data undermines Petitioner’s
argument that “[t]he distribution of indium within the indium-rich quantum
dots for a MQW sample disclosed by Gerthsen is shown” in Figure 4. Pet.
49.
Similar to its challenge based on Lin, Petitioner, in its Reply, appears
to shift its arguments and present improper new evidence in attempt to
establish that Gerthsen discloses carrier trap portions having the bandgap
energy profile required in claim 1.10 For example, in the Reply Petitioner
states that “Gerthsen’s conclusions do not rest solely on TEM” and
“Gerthsen’s analysis should be interpreted in light of the understanding that

10 To the extent Petitioner presents proper arguments in the Reply
responding to Patent Owner’s assertions regarding the limitations of
Gerthsen’s TEM measurements, these properly responsive arguments have
been considered and addressed above.
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indium-rich clusters allowed InGaN LEDs to be highly luminescent despite
their high levels of dislocations, consistent with the known literature.”
Reply 19. Once again, Petitioner’s Reply includes arguments based on the
natural behavior of indium clusters, the assertion that “InGaN exhibits
complex growth processes,” and evidence purporting to establish that InGaN
quantum wells naturally have a variation in indium composition. Reply
17–23 (citing Ex. 1071 ¶¶ 12–21; Ex. 1066 ¶¶ 27, 58, 61); Tr. 19:14–20:4
(referring to “how indium behaves”).
For the same reasons discussed above, we decline to consider
Petitioner’s new arguments and evidence. Wasica, 853 F.3d at 1287. Doing
so here results in weighing Petitioner’s reliance on Gerthsen Figure 4 as the
basis for its argument that Gerthsen discloses a carrier trap portion having
the bandgap energy profile claim 1 requires against Patent Owner’s evidence
that the TEM data presented in Gerthsen Figure 4 cannot be attributed to any
particular indium-rich quantum dot in Gerthsen. For the reasons discussed
above, the evidence Petitioner has presented does not demonstrate, by a
preponderance of evidence, that Gerthsen Figure 4 shows quantum dots that
satisfy the bandgap limitation in claim 1. Additionally, Petitioner’s
arguments regarding Dr. Doolittle’s purported admission are no more
persuasive here than they were when we considered them in connection with
Lin’s disclosures, and they do not cure the deficiencies in Petitioner’s
evidence.
Even if we did consider Petitioner’s evidence and arguments
presented for the first time in the Reply, the outcome here would not change.
For example, in its Reply, Petitioner states “Gerthsen describes a ‘high
accuracy’ analytical technique that is used to show composition fluctuations
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which are ‘always present in InGaN’ and the presence of ‘In-rich
agglomerates’ which ‘act optically as quantum dots.’” Reply 22 (quoting
Ex. 1026, 1669 (emphasis added by Petitioner)). Petitioner also contends
that Gerthsen provides plots that “demonstrate that the indium composition
varies from one position within the sample to the next.” Reply 22 (citing
Ex. 1026, 1673).
Because Petitioner acknowledges it is not presenting an inherency
argument, the fact that Gerthsen discloses indium-rich clusters that act as
quantum dots does not demonstrate that Gerthsen’s indium-rich quantum
dots have the specific bandgap energy profile required in claim 1.
Furthermore, based on the limitations of TEM discussed above, we are not
persuaded that the presence of composition fluctuations throughout an
InGaN layer—detected using TEM—demonstrates a variation of indium
composition within a carrier trap portion, as argued by Petitioner.
Petitioner also argues that “Gerthsen’s discussion of the formation of
the QDs is consistent with a variation in bandgap energy in the manner
claimed because indium exhibits temperature-dependent phase separation
during growth.” Reply 23 (citing Ex. 1026, 1679–1681; Ex. 1066 ¶ 58).
Petitioner cites to paragraph 58 in Dr. Ponce’s declaration in support of this
assertion. Reply 23. Dr. Ponce, however, does not discuss temperature-
dependent phase separation during growth in this paragraph. Ex. 1066 ¶ 58.
Instead, he refers to the Stransky-Krastanov (“SK”) growth mode in support
of his opinion that “[t]he only reasonable conclusion from the data shown in
[Gerthsen’s] Fig. 4 is that there are regions of higher indium content in the
quantum wells that have bandgap energies that decrease from a periphery of
the indium cluster towards the center of the cluster.” Ex. 1066 ¶ 58. As
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Patent Owner points out, however, Gerthsen states that SK growth does not
explain the indium-rich clusters observed it its samples. Ex. 1026, 1679 (“It
is, however, quite obvious, that an SK transition cannot be responsible for
the In-rich clusters . . . .”); see also Ex. 1026, 1680 (Gerthsen stating that
“we observe small and large-scale fluctuations [which] are also incompatible
with the theory of spinodal decomposition,” whereas Dr. Dupuis (Ex. 1071
¶¶ 12–13) and Petitioner (Reply 17) rely on spinodal decomposition to
explain InGaN’s “complex growth processes”).
Petitioner also relies on paragraph 21 in Dr. Dupuis’ Second
Declaration, wherein Dr. Dupuis states that “Gerthsen’s study is consistent
with the depictions in the ’225 patent,” and compares Figures 3 and 4 of the
’225 patent with Figures 4(a) and 4(b), respectively, of Gerthsen. Reply
22–23. Dr. Dupuis’ comparison, however, is flawed. First, what Dr. Dupuis
identifies as Figure 3 in Exhibit 1071 is different from Figure 3 in Exhibit
1001, which is the copy of the ’225 patent submitted by Petitioner.
Compare Ex. 1071 ¶ 21 with Ex. 1001, Fig. 3. Instead of Figure 3, it
appears Dr. Dupuis has reproduced a version of Figure 7 from the ’225
patent in paragraph 21 of his Second Declaration. See Ex. 1001, Fig. 7. The
’225 patent describes Figure 7 as “a diagram illustrating compressive stress
generated in a carrier trap portion and tensile stress generated in a barrier
layer to offset the compressive stress.” Ex. 1001, 3:22–24. We fail to see,
and Dr. Dupuis does not explain, how this figure can properly be compared
with Gerthsen Figure 4(a) which shows a “[c]olor-coded map of the In
distribution of an InGaN/GaN multiple QW structure.” Ex. 1026, 1673.
Additionally, Dr. Dupuis attempts to compare Figure 4 of the ’225
patent, which is an “energy band diagram” with Gerthsen Figure 4(b) which
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shows “averaged In concentration along the [1120] direction plotted as a
function of the (0002)-plane number.” Ex. 1001, 3:12–15; Ex. 1026, 1673.
Dr. Dupuis does not address the differences between the figures or otherwise
explain why Gerthsen’s study is consistent with the depictions in the ’225
patent.
Although Petitioner maps Gerthsen’s quantum dots to the carrier trap
portion recited in claim 1 in its Petition, in its Reply it attempts to rely on the
purported composition gradient in the matrix surrounding Gerthsen’s
quantum dots as evidence that the quantum dots themselves have the
bandgap energy profile recited in claim 1. Pet. 48–49; Reply 16–23. But we
are not persuaded that Petitioner’s evidence regarding the natural behavior
of indium during growth to form a composition gradient somewhere in a
quantum well shows a specific variation of indium composition within one
of Gerthsen’s indium-rich quantum dots itself. Sur-reply 4. This is
especially true considering the only indium composition measurements in
Gerthsen are based on TEM, which undisputedly provides average values
across a sample of unspecified thickness. Ex. 1026, 1674 (stating that
samples “typically range between 5 and 20 nm”). Thus, the evidence does
not demonstrate the presence of a composition gradient in a location
sufficient to identify a carrier trap portion having the bandgap energy
requirements in claim 1.
For all of the foregoing reasons, we find Petitioner has failed to
demonstrate, by a preponderance of evidence, that Gerthsen discloses a
carrier trap portion having the bandgap energy profile claim 1 requires, and
therefore, that Gerthsen anticipates claim 1.
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2. Claims 5–7, 10, 11, and 17–19
Claims 5–7, 10, 11, and 17–19 depend directly or indirectly from
claim 1, and therefore contain all the limitations of claim 1. In its analysis of
these dependent claims, Petitioner does not present any additional
information regarding Gerthsen’s disclosure of carrier trap portions having
the bandgap energy profile recited in claim 1. Pet. 50–56. Thus, for the
reasons discussed above in connection with claim 1, we determine Petitioner
has failed to establish sufficiently that Gerthsen teaches each limitation of
claims 5–7, 10, 11, and 17–19. In view of this, we determine Petitioner has
failed to demonstrate, by a preponderance of evidence, that Gerthsen
anticipates claims 5–7, 10, 11, and 17–19 of the ’225 patent.
G. Claim 16 — Obvious in view of Gerthsen and Lin II
Petitioner argues dependent claim 16 is unpatentable as obvious in
view of the combined teachings of Gerthsen and Lin II (Pet. 57–58). Claim
16 depends from claim 1, and therefore contains all of the limitations in
claim 1. Petitioner does not rely on Lin II to cure the deficiencies discussed
above regarding Petitioner’s assertion that Gerthsen discloses all of the
limitations in claim 1. Pet. 57–58. As a result, for the reasons discussed
above, we determine Petitioner has failed to demonstrate, by a
preponderance of evidence, that claim 16 is unpatentable as obvious in view
of Gerthsen and Lin II.

III. CONCLUSION
For the foregoing reasons, Petitioner has not demonstrated, by a
preponderance of the evidence, that claims 1, 4–7, 10, 11, and 16–19 of the
’225 patent are unpatentable over the prior art of record.
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In summary:
Claim(s)
Challenged
35
U.S.C. § Reference(s)
Claims
Shown
Unpatentable
Claim(s) Not
Shown
Unpatentable
1, 4–7, 10,
11, 17–19 102(b) Lin
1, 4–7, 10, 11,
17–19
4 103(a) Lin, Schley 4
16 103(a) Lin, Lin II 16
1, 5–7, 10,
11, 17–19 102(b) Gerthsen
1, 5–7, 10, 11,
17–19
16 103(a) Gerthsen, Lin II 16
Overall
Outcome
1, 4–7, 10, 11,
16–19

IV. ORDER
It is hereby
ORDERED that, Petitioner has not shown, by a preponderance of the
evidence, that claims 1, 4–7, 10, 11, and 16–19 of the ’225 patent are
unpatentable; and
FURTHER ORDERED that, because this is a final written decision,
parties to this proceeding seeking judicial review of our Decision must
comply with the notice and service requirements of 37 C.F.R. § 90.2.

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For PETITIONER:

Andrew Sommer
Barry J. Schindler
Heath J. Briggs
GREENBERG TRAURIG, LLP
sommera@gtlaw.com
schindlerb@gtlaw.com
briggsh@gtlaw.com

For PATENT OWNER:

Charles H. Sanders
Jonathan M. Strang
LATHAM & WATKINS LLP
charles.sanders@lw.com
jonathan.strang@lw.com