Ex Parte Xue et al

Patent Trial and Appeal Board

Jul 15, 2013

10910371 (P.T.A.B. Jul. 15, 2013)

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.
10/910,371 08/04/2004 Jiangeng Xue Y3422-91302 7798
111687 7590 07/15/2013
Duane Morris LLP (UDC)
30 South 17th Street
Philadelphia, PA 19103
EXAMINER
DICKEY, THOMAS L
ART UNIT PAPER NUMBER
2826
MAIL DATE DELIVERY MODE
07/15/2013 PAPER
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.
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte JIANGENG XUE, SOICHI UCHIDA,
BARRY P. RAND, and
STEPHEN FORREST
___________

Appeal 2010-011610
Application 10/910,371
Technology Center 2800
____________

Before JOSEPH F. RUGGIERO, ERIC B. CHEN, and
DANIEL N. FISHMAN, Administrative Patent Judges.

FISHMAN, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134(a) from the final rejection of
claims 1-12, 14-18, 21-23, 32-35, 42, and 43.
1
App. Br. 2. Claim 13 is
objected to as dependent on rejected claim but is deemed otherwise

1
Claim 13 was rejected under 35 U.S.C. § 101 and § 112 in the Final Office
Action mailed Sept. 25, 2009 from which this appeal was taken. However,
the Examiner withdrew the rejections of claim 13 in the Answer leaving
claim 13 merely objected to as dependent from rejected claim 1. Ans. 2-3.
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Application 10/910,371

2

allowable. Ans. 2. Claims 19, 20, 24-31, and 36-41 are cancelled. We have
jurisdiction under 35 U.S.C. § 6(b).
We reverse.

STATEMENT OF THE CASE
Appellants’ invention relates to a device having a photoactive region
disposed between two electrodes. The photoactive region includes a first
organic photoactive layer having a thickness not greater than 0.8
characteristic charge transport lengths and a second organic photoactive
layer having a thickness not less than about 0.1 optical absorption lengths.
See generally Abstract.
Claim 1 is illustrative, with disputed limitations in italics:
1. A device for generating photocurrent by absorbing
photons, comprising:
a first electrode;
a second electrode;
a photoactive region disposed between the first electrode
and the second electrode, the photoactive region further
comprising:
a first photoactive organic layer for generating excitons
by absorbing photons comprising a mixture of a small molecule
organic acceptor material and a small molecule organic donor
material, wherein the first organic layer has a thickness not
greater than 0.8 characteristic charge transport lengths; and
a second photoactive organic layer for generating
excitons by absorbing photons in direct contact with the first
photoactive organic layer, wherein: the second photoactive
organic layer comprises an unmixed layer of the small molecule
organic acceptor material of the first photoactive organic layer,
and the second photoactive organic layer has a thickness not
less than about 0.1 optical absorption lengths,
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wherein excitons generated by absorption of photons by
the first and second photoactive organic layers dissociate into
electrons and holes that contribute to the photocurrent.

THE REJECTIONS
Claims 1-12, 17, 22, 23, 32, 34, 35, and 42 are rejected under 35
U.S.C. § 102(b) as anticipated by Drechsel (High Efficiency Organic Solar
Cells Based On Single Or Multiple PIN Structures; Thin Solid Films 451-
453, pp. 515-517 (2004)). Ans. 4-11.
Claim 18 is rejected under 35 U.S.C. § 103(a) as unpatentable over
Drechsel and Uchida (U.S. Patent No. 5,587,444; issued Dec. 24, 1996).
Ans. 11-16.
Claims 14-16 and 21 are rejected under 35 U.S.C. § 103(a) as
unpatentable over Drechsel and Forrest (U.S. Patent Publication No.
2003/0042846 A1; published Mar. 6, 2003). Ans. 17.
Claims 1-12, 14-18, 21-23, 32-35, 42, and 43 are rejected under 35
U.S.C. § 112, first paragraph, as failing to provide enablement
commensurate with the scope of the claims. Ans. 17-24.
Claims 1-12, 14-18, 21-23, 32-35, 42, and 43 are rejected under 35
U.S.C. § 101 as directed to non-statutory subject matter. Ans. 25-27.

THE § 102 REJECTION
The Examiner finds that Drechsel teaches all elements of claim 1 and
specifically cites Drechsel’s layer labeled “n-C60 30nm” of Figure 3 as
showing the recited “second photoactive organic layer.” Ans. 5. Appellants
argue that Drechsel fails to show the recited second photoactive organic
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layer because the layer of Drechsel relied upon by the Examiner is not
“photoactive” as recited in claim 1. App. Br. 15.
Issue
Has the Examiner erred in finding that Drechsel teaches “a second
photoactive organic layer for generating excitons by absorbing photons . . .
wherein excitons generated by absorption of photons by the first and second
photoactive organic layers dissociate into electrons and holes that contribute
to the photocurrent” as recited in claim 1?
Analysis
We are persuaded by Appellants’ argument that Drechsel fails to show
the second layer as recited in claim 1. Appellants contend that the “n-C60”
layer relied upon by the Examiner to show the recited second layer is not a
photoactive layer as recited in the claim. App. Br. 15. Claim 1 recites
“wherein excitons generated by absorption of photons by the first and
second photoactive organic layers dissociate into electrons and holes that
contribute to the photocurrent.” To meet this limitation, both the recited first
and second layers must absorb photons such that they both contribute to the
photocurrent of the device.
The Examiner and Appellants engage is a detailed technical exchange
regarding characteristics of “C60” and “n-C60.” See, e.g., Ans. 30-41; Reply
Br. 1-5; Declaration of Co-Inventor Dr. Xue (App. Br. Evidence Appendix).
While we have reviewed the detailed positions presented by the Examiner
and Appellants regarding various properties of “C60” and “n-C60”, we find
that Drechsel explicitly teaches a device having only a single photoactive
layer:
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We show that the performance of organic solar cells can be
strongly improved using PIN structures with doped wide-gap
transport layers and a phthalocyanine-fullerene blend as a
photoactive layer. Such cells only absorb light in the
photoactive region and thus avoid recombination losses at the
contacts and make optimum use of the light reflected at the top
contact.
Drechsel Abstract (emphasis added). Figure 1(a) of Drechsel (reproduced
below) shows an abstraction of the “photoactive region” in the device of
Drechsel as discussed in the quoted portion of the Abstract:

Drechsel Figure 1(a) Showing a Device with a Single “Active Area”

The “n-C60” layer relied upon by the Examiner as showing the recited
second layer (shown Drechsel Figure 3) corresponds to the “wide-gap n-type
electron transport” layer of Drechsel’s Figure 1(a) and is not taught by
Drechsel to be an “active” layer that absorbs photons to thereby contribute to
the photocurrent as required of the second layer of claim 1. Rather,
Drechsel’s Abstract as quoted above makes clear that only the photoactive
region (“active areas, absorption” if Figure 1(a)) absorbs light and thus only
the single active area (i.e., single photoactive region) contributes to
photocurrent—not the “wide-gap n-type electron transport” layer relied upon
by the Examiner to teach the recited second photoactive organic layer. We
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therefore find that Drechsel does not teach, explicitly or inherently, a second
photoactive organic layer that absorbs photons and thereby contributes to the
photocurrent as required by claim 1. Whether the recited second layer of
claim 1 is obvious in view of Drechsel alone or in combination with other
references is not before us on this appeal.
2

In view of the above discussion we are persuaded that the Examiner
erred in finding that Drechsel teaches “a second photoactive organic layer
for generating excitons by absorbing photons . . . wherein excitons generated
by absorption of photons by the first and second photoactive organic layers
dissociate into electrons and holes that contribute to the photocurrent” as
recited in claim 1. We therefore do not sustain the rejection of claim 1 under
§ 102 and claims 2-12, 17, 22, 23, 32, 34, 35, and 42 dependent from claim 1
(directly or indirectly).

THE § 103 REJECTIONS
Claims 14-16, 18, and 21 depend from claim 1 (directly or indirectly)
and are rejected as unpatentable over Drechsel in combination with other
references. The additional references relied upon in the § 103 rejections are
not relied upon by the Examiner to overcome the above deficiencies of

2
The Examiner notes that there is disagreement with Appellants as regards a
definition of “photoactive” as required for the second layer recited in
claim 1. Ans. 6. The Examiner adopts a broad dictionary definition that
photoactive means “[c]apable of responding to light photoelectrically.” Id.
Though not an aspect of our decision, we suggest that the Examiner’s
definition is unreasonably broad in view of the narrower recitation of claim
1 that specifically requires the first and second photoactive layers absorb
photons and thereby contribute to photocurrent of the device. The
Specification supports this narrower construction of “photoactive.” See, e.g.,
Spec. ¶¶ 0029, 0030, 0036, and 0037.
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Drechsel with respect to claim 1. Thus, for the same reasons as claim 1, we
are persuaded of error in the Examiner’s rejections of claims 14-16, 18, and
21 under § 103 and do not sustain the rejections of claims 14-16, 18, and 21
under § 103.

THE § 112 REJECTION
The Examiner rejected claims 1-12, 14-18, 21-23, 32-35, 42, and 43
because the Specification “does not reasonably provide enablement for an
embodiment including a mixed C60/titanyl phthalocyanine [1:1] first organic
layer in a thickness not greater than 0.8 characteristic charge transport
lengths.” Ans. 18. The Examiner acknowledges that the Specification is
enabling for a device comprising a first layer including a variety of mixed
organic acceptor/donor materials. Id. (citing table 1 of the Spec.).
Specifically, with regard to the Examiner’s suggested “a mixed C60/titanyl
phthalocyanine [1:1] first organic layer”, the Examiner finds:
Specifically, the characteristic transport length of a combination
of C60 and titanyl phthalocyanine combined in a ratio of 1:1
(C60/TiOPC [1:1] in the nomenclature commonly used to
describe the sort of "mixed", "blended", or "bulk
heterojunction" layers Appellants claim as their "first
photoactive layer") was unknown as of the filing date. Such a
combination, in such a ratio, meets the limitations of the
claimed "first photoactive layer", but one skilled in the art
would have no idea how thick (in measurable units) to build
said layer in order to meet claim 1. For this reason the
specification does not enable any person skilled in the art to
which it pertains, or with which it is most nearly connected, to
make the invention commensurate with the full scope of these
claims.
Ans. 19. Appellants argue that a skilled artisan would know how to
determine the characteristic charge transport length of any suitable material
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based on the disclosure of the application—specifically based on equation
(3) of the Specification as discussed in ¶ 0086. App. Br. 6-13. More
specifically, Appellants argue:
Moreover, the characteristic charge transport length L is a
measurable property for any and all organic acceptor/donor
materials as determined by equation (3), As such, a person of
ordinary skill in the art can measure 0.8 characteristic charge
transport length for any suitable combination of organic
acceptor/donor materials, as described in the specification,
without the "preknowledge" the Examiner erroneously asserts.
Such a measurement can be made prior to assembling the
components of Claim 1 using known methods.
App. Br. 8.
Issue
Has the Examiner erred in finding that the Specification fails to enable
the skilled artisan to practice the invention without undue experimentation?
Analysis
We are persuaded that the Examiner erred in finding that the
Specification fails to enable the skilled artisan to practice the invention
without undue experimentation. Appellants argue that the Specification
discloses two methods for determining the characteristic charge transport
length (“CTL”) using equation (3) and further argue that the Examiner does
not indicate why these methods of the Specification fail to enable the skilled
artisan to determine the CTL of organic materials. App. Br. 8-9. We agree.
Although the Examiner discusses various factors (the “Wands
factors”) that the Examiner asserts indicate that undue experimentation is
required (Ans. 21-23), the Examiner’s analysis appears to ignore the specific
methods discussed in the Specification that Appellants assert teaches the
skilled artisan how to determine the CTL for any material. Rather, the
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Examiner “Wands factors” analysis (Ans. 21-23) focuses on a specific
mixed organic material (“C60/TiOPc”) that the Examiner finds is not
specifically discussed in the Specification and requires undue
experimentation to determine the material’s CTL.
Appellants acknowledge that their claimed invention is material-
independent but argue that the Specification teaches the skilled artisan
methods to determine the CTL for any suitable combination of organic
acceptor/donor materials. App. Br. 7-8. The Examiner has not shown that the
disclosed methods for determining CTL for any suitable combination of
organic acceptor/donor materials are incorrect. Appellants’ Specification is
not required to specifically recite enabling parameters/values for each
possible embodiment (i.e., each species) of the broad claim (i.e., a genus).
See, e.g., Utter v. Hiraga, 845 F.2d 993, 998 (Fed. Cir. 1988) (“A
specification may, within the meaning of 35 U.S.C. § 112 ¶ 1, contain a
written description of a broadly claimed invention without describing all
species that claim encompasses.”); see also Manual of Patent Examining
Procedures (“MPEP”) § 2164 (“However, to comply with 35 U.S.C. 112,
first paragraph, it is not necessary to ‘enable one of ordinary skill in the art
to make and use a perfected, commercially viable embodiment absent a
claim limitation to that effect.’ CFMT, Inc. v. Yieldup Int’l Corp., 349 F.3d
1333, 1338, 68 USPQ2d 1940, 1944 (Fed. Cir. 2003)”); see also MPEP
§ 2164.02 (“For a claimed genus, representative examples together with a
statement applicable to the genus as a whole will ordinarily be sufficient if
one skilled in the art (in view of level of skill, state of the art and the
information in the specification) would expect the claimed genus could be
used in that manner without undue experimentation”).
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In view of the above discussion, we are persuaded of error in the
Examiner’s finding that the Specification fails to enable the skilled artisan to
practice the invention without undue experimentation. We therefore do not
sustain the Examiner’s rejection of claims 1-12, 14-18, 21-23, 32-35, 42, and
43 under § 112.

THE § 101 REJECTION
The Examiner finds that the claims are directed to non-statutory
subject matter because they recite an abstract idea (i.e., equation (3) of the
Specification is used by the apparatus of the claims) and finds that claims
“cover every practical application of the abstract idea.” Ans. 25-27.
Appellants argue that the claims do not recite an abstract idea and thus do
not pre-empt all possible applications of the idea. App. Br. 3-6.
Issue
Does claim 1 recite an abstract idea so as to pre-empt all practical
applications of the abstract idea?
Analysis
We are persuaded by Appellants’ argument that claim 1 does not pre-
empt all practical applications of equation (3) of the Specification. Claim 1
recites a specific structure—a device for generating photocurrent comprising
two electrodes and a photoactive region disposed between the two
electrodes. In other words, claim 1 clearly recites a specific useful
application of the idea expressed by equation (3) (for determining the
“characteristic charge transport lengths” of any organic material suitable for
the recited photoactive application in the structure recited by claim 1).
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In view of the above discussion, we are persuaded that the Examiner
erred in finding that claim 1 recites an abstract idea so as to pre-empt all
practical applications of the idea.

DECISION
For the reasons discussed above, the Examiner’s decision rejecting
claims 1-12, 17, 22, 23, 32, 34, 35, and 42 under 35 U.S.C. § 102(b) is
reversed.
For the reasons discussed above, the Examiner’s decisions rejecting
claims 14-16, 18, and 21 under 35 U.S.C. § 103(a) are reversed.
For the reasons discussed above, the Examiner’s decision rejecting
claims 1-12, 14-18, 21-23, 32-35, 42, and 43 under 35 U.S.C. § 112, first
paragraph, is reversed.
For the reasons discussed above, the Examiner’s decision rejecting
claims 1-12, 14-18, 21-23, 32-35, 42, and 43 under 35 U.S.C. § 101 is
reversed.

REVERSED

kis