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Patent Trials and Appeals Board

Nov 26, 2019

13927306 - (D) (P.T.A.B. Nov. 26, 2019)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/927,306 06/26/2013 Yuval Saado 010829-9175.US00 1074
46844 7590 11/26/2019
PERKINS COIE LLP - Micron
PATENT-SEA
PO BOX 1247
SEATTLE, WA 98111-1247
EXAMINER
JORDAN, ANDREW
ART UNIT PAPER NUMBER
2883
NOTIFICATION DATE DELIVERY MODE
11/26/2019 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
patentprocurement@perkinscoie.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte YUVAK SAADO
Appeal 2019-002140
Application 13/927,306
Technology Center 2800
Before MARK NAGUMO, KAREN M. HASTINGS, and
JEFFREY W. ABRAHAM, Administrative Patent Judges.

ABRAHAM, Administrative Patent Judge.

DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1, 3, 4, 6–29, 31–40, and 43–48. We
have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42(a). Appellant identifies the real party in interest as Micron
Technology, Inc. Appeal Br. 2.
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Application 13/927,306

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CLAIMED SUBJECT MATTER
The claims are directed to photonic devices fabricated over
semiconductor substrates. Spec. ¶ 1. Claim 1, reproduced below from the
Claim Appendix (App. Br. 13), is illustrative of the claimed subject matter:
1. An integrated structure comprising:
a semiconductor substrate having a silicon material;
optical cladding formed in the substrate, the cladding
comprising a plurality of spaced trenches formed in the
silicon material, wherein the trenches are filled with oxide,
and wherein the depth (d) of the trenches is less than the
thickness of the silicon material;
and a waveguide comprising a core, the core being formed as
a continuous slab of core material over the optical cladding
and in direct contact with the silicon material and the oxide
of the optical cladding.
REJECTIONS ON APPEAL
On appeal, the Examiner maintains several rejections:
A. Claims 1, 3, 4, 6, 7, 10–12, 19–21, and 25 under 35 U.S.C. § 103
as unpatentable over Block2 in view of Barrios;3
B. Claims 26–29, 31, 33–40, 43–46, and 48 under 35 U.S.C. § 103 as
unpatentable over Block in view of Allan4 and Barrios;
C. Claims 8 and 9 under 35 U.S.C. § 103 as unpatentable over Block
in view of Mouli5 and Barrios;
D. Claims 13–17 and 22–24 under 35 U.S.C. § 103 as unpatentable
over Block in view of Allan and Barrios; and

2 Block et al., US 6,993,212 B2, issued Jan. 31, 2006.
3 Barrios et al., US Pub. No. 2010/0142877 A1, published June 10, 2010.
4 Allan et al., US 6,674,949 B2, issued Jan. 6, 2004.
5 Mouli, US Pub. No. 2005/0281524 A1, published Dec. 22, 2005.
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E. Claims 18, 32, and 47 under 35 U.S.C. § 103 as unpatentable over
Block in view of Allan and Barrios, and further in view of
Applicant-Admitted Prior Art.
Final Act. 3–28; Ans. 2.
OPINION
Appellant presents arguments for independent claims 1, 26, and 38,
but does not present any arguments for the dependent claims that depend
from these claims. App. Br. 4–12. Therefore, we limit our discussion to
independent claims 1, 26, and 38, which we select as representative under 37
C.F.R. § 41.37(c)(1)(iv). By this rule, claims 3, 4, and 6–25 stand or fall
with claim 1, claims 27–29 and 31–37 stand or fall with claim 26, and
claims 39, 40, and 43–48 stand or fall with claim 38.
Claim 1
Claim 1 recites an integrated structure comprising “a semiconductor
substrate having a silicon material,” and “an optical cladding formed in the
substrate.” App. Br. 13. The optical cladding comprises “a plurality of
spaced trenches formed in the silicon material,” wherein the depth of the
trenches is less than the thickness of the silicon material. Id. Claim 1 also
requires a waveguide comprising a core, the core being formed over the
optical cladding. Id.
The Examiner contends that silicon substrate 101 and oxide lower
cladding 140 of Block correspond to the semiconductor substrate recited in
claim 1. Final Act. 4. The Examiner further contends that Block discloses
an optical cladding formed in the substrate. Id. (citing Block, 3:53–59 and
the “first cladding layer 140” in Figure 1 of Block). The Examiner
acknowledges that Block does not disclose a cladding comprising a plurality
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of spaced trenches in the silicon material, or that the depth of the trenches is
less than the thickness of the silicon material. Id.
The Examiner indicates that Barrios discloses a waveguide made of
multiple silicon layers, having cladding comprising spaced trenches in its top
silicon layer, wherein the depth of the trenches is less than the thickness of
the silicon material because the trenches are only in the top silicon layer.
Final Act. 5. According to the Examiner, it would have been obvious to
include the trenched cladding structure of Barrios as the cladding in Block’s
system. Id.
Appellant argues that Block and Barrios fail to disclose or suggest
each feature of claim 1, including a cladding formed in the substrate having
trenches with required thickness. App. Br. 7–8. With reference to Figure 1
of Block, Appellant contends that Block includes a cladding layer 140
formed on the substrate. Id. at 5. With reference to Figure 1 of Barrios,
Appellant contends that Barrios discloses a modulator formed on a buried
oxide layer which is supported by a silicon substrate. Id. at 6. Appellant
also argues that the portion of Barrios having trenches is not the optical
cladding formed in the substrate, as claim 1 requires, but is instead part of
the waveguide of claim 1 that is formed over the optical cladding. Id. at 6–
7.
The Examiner bears the initial burden of presenting a prima facie case
of obviousness. In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992).
“[R]ejections on obviousness grounds cannot be sustained by mere
conclusory statements; instead, there must be some articulated reasoning
with some rational underpinning to support the legal conclusion of
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obviousness.” In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006), quoted with
approval in KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007).
After review of the respective positions provided by Appellant and the
Examiner, we conclude that the preponderance of the evidence supports
Appellant’s position that the Examiner has not established a prima facie case
of obviousness.
The Examiner takes the position that the “substrate” in Block and
Barrios is comprised of multiple layers. Final Act. 4–5. In particular, the
Examiner contends that a substrate is not just the layer expressly identified
as the “substrate” in the references, but includes additional layers on top of
the substrate. Id. (referencing layers 101 and 140 in Fig. 1 of Block and
layers 140, 110, and 115 in Fig. 1 of Barrios). The broadest reasonable
interpretation of “substrate” as recited in claim 1 and consistent with the
Specification, however, does not encompass the Examiner’s purported
expansion of “substrate” in Block and Barrios to include other layers formed
on the layer expressly identified as the substrate in those references.
“[D]uring examination proceedings, claims are given their broadest
reasonable interpretation consistent with the specification.” In re Translogic
Tech., Inc., 504 F.3d 1249, 1256 (Fed. Cir. 2007) (quoting In re Hyatt, 211
F.3d 1367, 1372 (Fed. Cir. 2000)). See also In re America Acad. of Sci.
Tech Ctr., 367 F.3d 1359, 1364 (Fed. Cir. 2004) (The scope of the claims in
patent applications is not determined solely on the basis of the claim
language, but upon giving claims their broadest reasonable construction in
light of the specification as it would be interpreted by one of ordinary skill in
the art.). As stated in In re Smith,
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The correct inquiry in giving a claim term its broadest
reasonable interpretation in light of the specification is not
whether the specification proscribes or precludes some broad
reading of the claim term adopted by the examiner. And it is not
simply an interpretation that is not inconsistent with the
specification. It is an interpretation that corresponds with what
and how the inventor describes his invention in the specification,
i.e., an interpretation that is “consistent with the specification.”
In re Smith Int’l, Inc., 871 F.3d 1375, 1382–83 (Fed. Cir. 2017) (quoting In
re Morris, 127 F.3d 1048, 1054 (Fed. Cir. 1997)).
The Specification, referring to Figure 1(A), describes a structure
having a lower cladding formed in a substrate, and distinguishes, by name,
the substrate from other layers formed over the substrate. Spec. ¶ 13.
Figure 1(A) of the present application is reproduced below.

Figure 1(A) of the present application shows photonic device 100 formed on
substrate 101, having waveguide core 105, and lower cladding formed by
crystal 103 in substrate 101. Spec. ¶ 13. As shown in Figure 1(A), trenches
109 of photonic crystal 103 are formed in the single-layer substrate 101. Id.
¶ 14. By contrast, the waveguide core 105 is depicted as a separate layer
over the cladding that is in the single-layer substrate 101, consistent with the
language in claim 1,
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In other places, the Specification consistently identifies the substrate
as an independent layer, distinguished from other layers formed over it. For
example, with reference to Figures 3(A) and 3(B), the Specification
describes a process of forming the photonic device wherein mask 113 is
formed over substrate 101. Figure 3(B) is reproduced below.

Figure 3(B) shows the patterned mask 113 formed over the single-layer
substrate 101.
In light of the Specification and claims differentiating between
elements formed in the substrate and over/on the substrate, the Examiner’s
reliance on elements formed on the substrate in Block and Barrios as being
formed in the substrate, as recited in claim 1, is unfounded.
Figure 1 of Block is reproduced below.

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Figure 1 shows a cross sectional view of an integrated waveguide device,
having oxide lower cladding 140 on substrate 101. Block’s description of
Figure 1 confirms that “a first cladding layer 140 is formed on the substrate
101.” Block, 3:49–54, Fig. 1. Thus, we agree with Appellant that Block
shows a cladding on the substrate, not in the substrate as the Examiner
contends, and claim 1 requires. App. Br. 5; Final Act. 4.
The Examiner’s reliance on Barrios does not cure this deficiency.
Figure 1 of Barrios is reproduced below:

Figure 1 shows an electro-optic modulator 100 having top silicon layer 140
on buried oxide (BOX) layer 110 and silicon substrate 115. Barrios, Fig. 1,
¶¶ 16–17. Although Barrios discloses a structure having trenches in silicon
layer 140, that silicon layer is formed over a separate BOX layer (110),
which is formed on another layer expressly identified as the “Si Substrate”
(115). See Barrios ¶ 16 (stating that the modulator is formed on a buried
oxide (BOX) layer 110 supported by a silicon substrate 115”). Thus, to the
extent a person of ordinary skill in the art would consider layer 140 of
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Barrios to be an optical cladding, a matter on which we make no finding,
that layer is formed on a BOX layer, which is itself formed on a separately-
identified substrate. As a result, layer 140 does not satisfy the requirement
in claim 1 that the optical cladding is formed in the substrate.
Thus, the Examiner fails to show that Block and/or Barrios disclose or
suggest each limitation of claim 1, namely a cladding formed in the
substrate. Moreover, the Examiner’s discussion of reasons why a person of
ordinary skill in the art would have combined the teachings of Block and
Barrios does not cure this deficiency. Final Act. 5–6; Ans. 2–3. Even if a
person of ordinary skill in the art would have been motivated to use the
“cladding” of Barrios in place of any cladding layer of Block, it is not clear
how that modified Block structure would provide an optical cladding layer
formed in the substrate, as claim 1 requires. See Final Act. 5–6.
Because the Examiner fails to demonstrate sufficiently that Block and
Berrios disclose or suggest each limitation of claim 1, we reverse the
Examiner’s rejection of claim 1, and claims 3, 4, and 6–25, which depend
therefrom.
Claim 26
Similar to claim 1, claim 26 is drawn to an integrated structure, and
recites “a lower cladding formed as a photonic crystal within a silicon
substrate,” having trenches of a depth less than the thickness of the substrate.
App. Br. 16 (emphasis added). Claim 26 further requires a core formed on
the lower cladding. Id.
As with the rejection of claim 1, the Examiner relies on the
combination of Block and Barrios as disclosing a lower cladding comprising
a plurality of trenches formed within the silicon substrate. Final Act. 10–12.
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The Examiner relies on Allan for its disclosure of an active photonic crystal
waveguide. Id. at 11.
Appellant’s arguments regarding claim 26 are similar to those
presented in response to the rejection of claim 1. App. Br. 8–10. For
example, Appellant argues that the combined teachings of Block, Barrios,
and Allen fail to disclose every feature of claim 26, including, inter alia, a
lower cladding formed as a photonic crystal within a silicon substrate,
having the trenches recited in claim 26. Id. at 9.
In view of the similar arguments made by the Examiner and
Appellant, we reverse the rejection of claim 26 for the same reasons
discussed above regarding claim 1. In particular, the Examiner fails to
demonstrate adequately that Block and Barrios disclose a lower cladding
formed within a silicon substrate, and a core formed on the lower cladding,
as claim 26 requires. Nor does the Examiner demonstrate adequately that
Allan cures this deficiency.
Because the Examiner fails to prove that Block, Barrios, and Allan
disclose or suggest each limitation of claim 26, we reverse the Examiner’s
rejection of claim 26, and claims 27–29 and 31–37, which depend therefrom.
Claim 38
Claim 38 recites a method for forming an integrated structure,
comprising “forming a photonic crystal on a silicon substrate wherein the
photonic crystal is formed by positioning spaced trenches within a silicon
layer, the depth (d) of the spaced trenches is less than the thickness of the
substrate.” App. Br. 17.
The Examiner contends that Allen and Block together disclose
forming a photonic crystal on a silicon substrate, and that Barrios discloses
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that the depth of the trenches is less than the thickness of the substrate,
relying on an analysis similar to the analysis provided for claims 1 and 26.
Final Act. 17 (“In achieving the structure as set forth in claims 1 and 26,
above, Block in view of Allan and Barrios as set forth above would achieve
the method of claim 38.”). Appellant disputes that Allan, Block, and Barrios
disclose these features, and argues that a person of ordinary skill in the art
would not be motivated to modify the teachings of the references to arrive at
a structure having these features. App. Br. 11.
Unlike claim 26, Claim 38 recites a photonic crystal formed on a
silicon substrate, not within the substrate. Similar to claim 26, however,
claim 38 still requires that the depth of the trenches of the photonic crystal is
less than the thickness of the substrate. We agree that the combined
disclosure of Block, Allen, and Barrios discloses trenches in a layer formed
on a substrate. The Examiner, however, does not direct us to evidence
sufficient to determine whether the depth of the trenches in Barrios is less
than the thickness of the substrate. The Examiner relies on Figures 1 and 2
of Berrios (Final Act. 17), which show trenches in layer 140, situated above
the Si Substrate layer 115. The figures do not contain any quantitative
values from which a person of ordinary skill in the art could determine
relative depths of the trenches compared to the thickness of the substrate.
Nor are we persuaded by the Examiner’s reasoning (provided with
regard to the rejection of claim 1) that the depth of the trenches in Barrios is
less than the thickness of the silicon material of the substrate because the
trenches are only in the top silicon layer 140. Final Act. 5. This argument is
based on the Examiner’s position that the silicon layer 140 is in the
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substrate, not on the substrate. For the reasons discussed above, however,
this position is unfounded.
As a result, we find the Examiner has failed to demonstrate adequately
that the combined teachings of Block, Barrios, and Allan disclose or suggest
“forming a photonic crystal on a silicon substrate wherein the photonic
crystal is formed by positioning spaced trenches within a silicon layer, the
depth (d) of the spaced trenches is less than the thickness of the substrate.”
App. Br. 17. Moreover, the Examiner’s discussion of reasons why a person
of ordinary skill in the art would have combined the teachings of Block,
Barrios, and Allan does not cure this deficiency. Final Act. 5–6, 11; Ans.
2–6.
Because the Examiner failed to prove that Block, Barrios, and Allan
disclose or suggest each limitation of claim 38, we reverse the Examiner’s
rejection of claim 38, and claims 39, 40, and 43–48, which depend
therefrom.
CONCLUSION
The Examiner’s rejections are reversed.
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1, 3, 4, 6, 7,
10–12, 19–
21, 25
103 Block, Barrios 1, 3, 4, 6, 7,
10–12, 19–
21, 25
26–29, 31,
33–40, 43–
46, 48
103 Block, Barrios,
Allan
26–29, 31,
33–40, 43–
46, 48
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8, 9 103 Block, Mouli,
Barrios
8, 9
13–17, 22–
24
103 Block, Allan,
Barrios
13–17, 22–
24
18, 32, 47 103 Block, Allan,
Barrios, AAPA
18, 32, 47
Overall
Outcome
1, 3, 4, 6–
29, 31–40,
43–48

REVERSED