Ex Parte HEKMATSHOAR-TABARI et al

Patent Trial and Appeal Board

May 6, 2016

13163137 (P.T.A.B. May. 6, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/163,137 06/17/2011
49267 7590 05/10/2016
TUTUNJIAN & BITETTO, P,C
401 Broadhollow Road, Suite 402
Melville, NY 11747
FIRST NAMED INVENTOR
BARMAN HEKMATSHOAR-TABARI
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
ATTORNEY DOCKET NO.
YOR920110313US 1
(163-421)
CONFIRMATION NO.
9031
EXAMINER
MERSHON, JAYNE L
ART UNIT PAPER NUMBER
1758
NOTIFICATION DATE DELIVERY MODE
05/10/2016 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):
patents@tb-iplaw.com
sandy@tb-iplaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte BARMAN HEKMATSHOAR-TABARI,
DEVENDRA K. SADANA, GHA VAM G. SHAHID!, and
DA VOOD SHAHRJERDI
Appeal2014-006654
Application 13/163,137 1
Technology Center 1700
Before PETER F. KRATZ, RICHARD M. LEBOVITZ, and
KAREN M. HASTINGS, Administrative Patent Judges.
LEBOVITZ, Administrative Patent Judge.
DECISION ON APPEAL
This appeal involves claims directed to a method for fabricating a
photovoltaic device. Appellants appeal from the Examiner's final rejection
of claims 17-27 as obvious under 35 U.S.C. § 103. We have jurisdiction
under 35 U.S.C. § 134. The rejections under§ 103 are affirmed.
1 "The '137 Application."
Appeal2014-006654
Application 13/163,137
STATEMENT OF CASE
Claims 17-27 stand finally rejected by the Examiner as follows:
Claims 17-23, 26, and 27 stand rejected under 35 U.S.C. § 103(a)
(pre-AIA) as obvious in view of Tiedje et al. (US 4,598,164, issued July 1,
1986) ("Tiedje"). Final Rej. 3.
Claims 24 and 25 stand rejected under 35 U.S.C. § 103(a) (pre-AIA)
as obvious in view of Tiedje and Moslehi (US 2009/0301549 Al, published
Dec. 10, 2009) ("Moslehi"). Final Rej. 6.
Claims 26 and 27 stand rejected under 35 U.S.C. § 103(a) (pre-AIA)
as obvious in view of Tiedje and Varonides et al. (a-Si:H (Alloy) p-i-n
Superlattice Solar Cell Contacts, 39 IEEE Transactions on Electron Devices
2284--2289 (1992)) ("Varonides"). Final Rej. 7.
Claim 17 is the only independent claim on appeal. Claim 17 reads as
follows:
17. A method for fabricating a photovoltaic device,
compnsmg:
providing a substrate;
forming a plurality of layers including alternating wide
band gap and narrow band gap layers to form a superlattice to
provide a multilayer with an effectively increased band offset
with the substrate and/or effectively increased doping level over
a single material contact;
forming a conductive contact on the superlattice; and
forming a contact structure on the substrate on a side
opposite the superlattice.
DISCUSSION
Claim 17 is directed to a method of fabricating a photovoltaic device.
The method includes the step of "forming a plurality of layers including
alternating wide band gap and narrow band gap layers to form a
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superlattice." The Examiner found that Tiedje describes a superlattice of
alternating wide band and narrow band gap layers. Final Rej. 3.
Appellants acknowledge that "although Tiedje discusses alternating
layers of a superlattice material having different compositions from each [ ]
other in col. 2, lines 50-65, there is no discussion regarding layers with
alternating wide and narrow band gaps in Tiedje." Br. 10. Appellants argue
that "the e V of band gaps in narrow regions increases within the band gap
region itself .... Furthermore, all the band gaps in Tiedje are in the range of
1.2-2 e V, while the narrow band gaps in the present invention are in the
range of below 1 eV." Id. Appellants rely on paragraph 23 of the' 137
Application as defining the narrow band gap as having an e V of less than
one. Id. at 11.
We first tum to the interpretation of "narrow band gap" because,
before a claim can be compared to the prior art, it must be properly
interpreted.
Interpretation of the claim term "narrow band gap"
Appellants cited paragraph 23 of the '13 7 Application as defining
"narrow band gap" as having an e V of one or less and "wide band gap" as
larger than 1 or 2 e V. Paragraph 23 is reproduced below (emphasis added):
In accordance with the present principles, an emitter side 110 of
the substrate 102 includes a superlattice stack of layers 120.
The stack 120 of layers includes alternating wide band gap
(high band gap or wide gap) layers 122 (e.g., doped layers) and
narrow band gap (low band gap or narrow gap) layers 124 (e.g.,
intrinsic layers). The number of layers n is greater than 2. Wide
gap layers 122 include a wide band gap semiconductor, which
is a semiconductor material with an electronic band gap larger
than one or two electronvolts (e V). The narrow gap layers 124
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Application 13/163,137
include semiconducting materials with a band gap that is
comparatively small compared to silicon. Each wide-gap layer
and narrow-gap layer may include a doped layer (n+ dopants)
or an undoped layer, or an intrinsic layer (i-layer). An optional
intrinsic layer 126 may be interposed between the stack 120 and
the substrate 102. In one embodiment, the superlattices 120,
132 include alternating doped and intrinsic layers.
Paragraph 23 states that the wide band gap is "larger than one or two
electronvolts ( e V)" and the narrow band gap "is comparatively small
compared to silicon." Appellants state that "one of ordinary skill in the art
would know that the band gap of silicon is less than one e V." Br. 11.
The evidence does not support Appellants' argument that paragraph 23
defines the e V of the narrow band and broad band gaps. Paragraph 23
appears under the section titled "Detailed Description of Preferred
Embodiments." Based on this, paragraph 23 is reasonably presumed to be a
description of preferred examples ("embodiments") of narrow and broad
band gaps. "[A] particular embodiment appearing in the written description
may not be read into a claim when the claim language is broader than the
embodiment." SuperGuide Corp. v. DirecTV Enterprises, Inc., 358 F.3d
870, 875 (Fed. Cir. 2004). The claims recite "alternating wide band gap and
narrow band gap layers," but do not assign e V values to the gap layers or
provide a hook which would require the skilled worker to necessarily read
the claim terms to be limited to the preferred values of larger than one or two
for the broad band gap, and less than one for the narrow band gap.
Moreover, the '13 7 Application expressly states that the preferred
embodiments are not limiting:
Having described preferred embodiments for improved contact
for silicon heterojunction solar cells (which are intended to be
illustrative and not limiting), it is noted that modifications and
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Application 13/163,137
variations can be made by persons skilled in the art in light of
the above teachings.
'13 7 Application i-f 51. (Emphasis added.)
Accordingly, the narrow reading of the claim advanced by Appellants
is inconsistent with' 137 Application. The PTO must give claims their
broadest reasonable construction consistent with the specification. In re Am.
Acad. of Sci. Tech Ctr., 367 F.3d 1359, 1364 (Fed. Cir. 2004); In re Suitco
Surface, Inc., 603 F.3d 1255, 1259 (Fed. Cir. 2010); In re Abbott Diabetes
Care Inc., 696 F.3d 1142, 1148 (Fed. Cir. 2012).
We now tum to the rejections. The following facts are pertinent to the
obviousness determination.
Findings of Fact ("FF")
FPL Tiedje describes an amorphous superlattice which a
"multilayered material." Tiedje, col. 2, 11. 51-52. Tiedje teaches that "the
first and alternate layers 1, 3, 5 of the structure have the same given
composition while the second and alternate 2, 4, 6 ... have the same
composition different from the given composition of layers 1, 3, 5 .... " Id.
at col. 2, 11. 59---63.
FF2. Tiedje provides several examples of alternating layers,
including:
FF3. a-Si:H/a-Si1-xCx:H ("50"). Fig. 6; col. 5, 1. 37; col. 6, 1. 5; Fig.
11.
FF4. a-Si:H/a-Ge:H/ ("30"). Fig. 6; col. 5, 1. 35; col. 6, 1. 55; Fig. 9.
FF5. The Examiner found that Fig. 11 shows a-Si:H (about 1.5 eV)
and a Si1-xC:H (about 1.9 eV).
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FF6. The '137 Application discloses that the narrow gap layer (which
is an intrinsic or i-layer) can be a-Si:H. '137 App. i-f 23 ("narrow band gap
(low band gap or narrow gap) layers 124 (e.g., intrinsic layers)"); i-f 24
("Semiconducting material( s) forming passivation intrinsic layers or i-
layer(s) may include a-Si:H").
FF7. The '13 7 Application discloses that the wide gap layer can be a
SiC:H material. '137 App. i-f 23 ("wide band gap (high band gap or wide
gap) layers 122 (e.g., doped layers)"); i-f 24 ("The semiconducting
material( s) forming doped/undoped layer( s) may include amorphous,
nanocrystalline, microcrystalline or polycrystalline films(s) of ... SiCx ...
and may or may not contain hydrogen").
FF8. The' 137 Application discloses the narrow gap layer (which can
be an intrinsic or i-layer) can be a-Ge:H. '137 App. i-f 23 ("narrow band gap
(low band gap or narrow gap) layers 124 (e.g., intrinsic layers)"); i-f 24
("Semiconducting material( s) forming passivation intrinsic layers or i-
layer(s) may include ... a-Ge:H").
FF9. The' 137 Application disclose that the wide gap layer can be a-
Si:H material. '137 App. i-f 23 ("wide band gap (high band gap or wide gap)
layers 122 (e.g., doped layers)"); i-f 24 ("The semiconducting material(s)
forming doped/undoped layer( s) may include amorphous, nanocrystalline,
microcrystalline or polycrystalline films( s) of ... Si ... and may or may not
contain hydrogen").
Discussion
The Examiner found that Tiedje describes a photovoltaic device a
superlattice comprising alternating band gaps of different materials which
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have different eV values. Final Rej. 3; FFI. The Examiner found that
Tiedje describes a superlattice of alternating layers of Si and SiC materials
(Final Rej. 3; FF3), the same materials described in the Specification as
suitable for narrow and broad band gap layer (FF6, FF7, respectively). The
Examiner also found that Tiedje describes a second superlattice of
alternating layers of Ge and Si materials (Final Rej. 4; FF4), the same
materials described in the Specification as suitable for narrow and broad
band gap layer (FF8, FF9, respectively). Based on these teachings, the
Examiner found that Tiedje describes a photovoltaic device within the scope
of the claim. Final Rej. 3--4.
Appellants contend that "Tiedje discusses alternating layers of a
superlattice material having different compositions from each - other in col.
2, lines 50-65, there is no discussion regarding layers with alternating wide
and narrow band gaps in Tiedje." Br. 10, 11.
It is true that Tiedje does not describe alternating layers of narrow and
broad gap band materials, but Tiedje describes alternating layers of materials
in which the materials are the same as the materials for the narrow and broad
gap bands disclosed in the '137 Application (FF6-FF9). Because the
materials in Tiedje and the '137 Application are the same, the Examiner had
reasonable basis to find the claim limitations met inherently by Tiedje. See
In re Best, 562 F.2d 1252, 1255 (CCPA 1977).
Appellants attempt to distinguish Tiedje by arguing that that the
narrow band gap material must have an e V of less than one. Br. 10.
However, we considered their interpretation of "narrow gap" material, and
found it to be unreasonable.
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Appellants state, that as discussed in column 7, lines 25-30 of Tiedje,
"the e V of band gaps in narrow regions increases within the band gap region
itself, and there is no mention of alternating narrow and wide band gaps in
Tiedje in any way whatsoever." Br. 10. The claim does not exclude
changes in the e V within the band gap layers. Tiedje, as found by the
Examiner expressly describes alternating layers of two band gap materials.
FF 1. Figures 9 and 11 of Tiedje show that the two different materials having
different e V characteristics, with one higher than the other. Thus,
Appellants' statement that the materials "may have equivalent band gaps" is
not supported by a preponderance of the evidence because Figures 9 and 10
clearly show non-equivalent band gaps utilized by Tiedje. Br. 10. Even if
true that there are certain embodiments where the alternating materials can
have equivalent e Vs (id. at 11 ), Figs. 9 and 11 clearly show instances where
they are not equivalent and therefore non-equivalent alternating materials
were considered by Tiedje to be suitable for a superlattice.
For the foregoing reasons, we affirm the rejection of claim 17.
Appellants did not provide separate arguments for the remaining claims or
rejections. Consequently, claims 18-27 fall with claim 17. See 37 C.F.R.
§ 41.37(c)(iv).
TIME PERIOD
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(l )(iv).
AFFIRMED
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