Ex Parte Buller et al

Patent Trial and Appeal Board

Oct 29, 2014

11378847 (P.T.A.B. Oct. 29, 2014)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD

____________

Ex parte BENYAMIN BULLER, CHRIS M. GRONET,
RATSON MORAD, and MARKUS E. BECK
__________

Appeal 2012-010068
Application 11/378,847
Technology Center 1700
____________

Before CATHERINE Q. TIMM, LINDA M. GAUDETTE, and
MICHAEL P. COLAIANNI, Administrative Patent Judges.

COLAIANNI, Administrative Patent Judge.

DECISION ON APPEAL
Appellants appeal under 35 U.S.C. § 134 the final rejection of claims
1–3, 6, 9–13, 15, 16, 34–45, 52, 88–92, 96, 97, 100–110, and 120. We have
jurisdiction over the appeal pursuant to 35 U.S.C. § 6(b).
We AFFIRM-IN-PART.
Appellants’ invention is directed to cylindrical-shaped solar cells in a
transparent tubular casing (Spec. 6:32–33).
Claim 1 is illustrative:
1. A solar cell unit comprising:
(A) a solar cell comprising:
a substrate that is either (i) tubular or (ii) a solid rod;
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a back-electrode circumferentially disposed on the substrate;
a semiconductor junction circumferentially disposed on said
back-electrode,
wherein said semiconductor junction comprises a first layer
circumferentially disposed on a second layer, wherein said first layer
comprises a first composition that comprises a first semiconductor and said
second layer comprises a second composition that comprises a second
semiconductor, wherein said first semiconductor is different than said
second semiconductor and wherein the first composition in the first layer
forms a semiconductor junction with said second composition in said second
layer, wherein the first semiconductor or the second semiconductor is
an absorber; and
a transparent conductive layer circumferentially disposed on
said semiconductor junction; and
(B) a transparent tubular casing circumferentially disposed onto said
solar cell, wherein a photovoltaic current generated by the solar cell unit is
from absorption of light by the absorber.

The Examiner maintains, and Appellants appeal, the following
rejections:1
1. Claim 120 is rejected under 35 U.S.C. § 112, first paragraph, as
failing to comply with the written description requirement.
2. Claims 1, 2, 6, 9–12, 15, 16, 43–45, 88, 89, 96, 97 and 100 are
rejected under 35 U.S.C. § 103(a), as being unpatentable over
Chittibabu et al. (US 2005/0040374 A1, published Feb. 24, 2005) in
view of Gebeyehu et al. (Hybrid solar cells based on dye-sensitized
nanoporous TiO2 electrodes and conjugated polymers as hole
transport materials, 125 Synthetic Metals 279–287 (2002)) as
evidenced by Antony et al. (Realization of red light-emitting diodes
with a confinement layer, 12 Optical Materials 291–294 (1999)), Park

1 The Examiner withdrew a rejection of claim 120 under 35 U.S.C. § 112,
second paragraph (Ans. 4).
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et al. (Structural and optical properties of rutile and anatase TiO2 thin
films: Effects of Co doping, 484 Thin Solid Films 34–38 (2005)),
Gueymard et al. (Proposed Reference Irradiance Spectra For Solar
Energy Systems Testing, 73 Solar Energy 443–467 (2002)), and Mylar
and Refraction websites.
3. Claims 3, 101, 105, 106, and 110 are rejected under 35 U.S.C.
§ 103(a), as being unpatentable over Chittibabu in view of Gebeyehu,
Nakata (WO 2004/001858 A1, published Dec. 31, 2003, relying upon
US 2006/0086384 A1, published Apr. 27, 2006 as a translation) or
Sugita et al. (JP 2000-294821A, published Oct. 20, 2000).
4. Claim 13 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Chittibabu in view of Gebeyehu and Fujimori et al. (US
6,683,244 B2, patented Jan. 27, 2004).
5. Claim 34 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Chittibabu in view of Gebeyehu and Mlavsky (US 4,078,944,
patented Mar. 14, 1978).
6. Claim 35 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Chittibabu in view of Gebeyehu, Mlavsky, and Baumeister et al.
(US 4,783,373, patented Nov. 8, 1988).
7. Claims 36–40 and 42 are rejected under 35 U.S.C. § 103(a) as being
unpatentable over Chittibabu in view of Gebeyehu and Weinstein et
al. (US 3,990,914, patented Nov. 9, 1976).
8. Claim 41 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Chittibabu in view of Gebeyehu, Weinstein, and Nath et al. (US
5,474,620, patented Dec. 12, 1995).
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9. Claims 52 and 90 are rejected under 35 U.S.C. § 103(a) as being
unpatentable over Chittibabu in view of Gebeyehu, Mlavsky, and
Yamashita et al. (US 7,094,452 B2, patented Aug. 22, 2006).
10. Claims 91 and 92 are rejected under 35 U.S.C. § 103(a) as being
unpatentable over Chittibabu in view of Gebeyehu, and Trupke et al.
(Improving solar cell efficiencies by down-conversion of high-energy
photons, 92 J. Appl. Phys. 1668–1674 (2002)).
11. Claims 102–104 and 107–109 are rejected under 35 U.S.C. § 103(a)
as being unpatentable over Chittibabu in view of Gebeyehu, Nakata,
Beauchamp et al. (US 5,449,413, patented Sept. 12, 1995), and Thelen
(US 3,247,392, patented Apr. 19, 1966).
12. Claims 1–3, 6, 9–13, 15, 16, 43–45, 88, 89, 96, 97, and 100 are
rejected under 35 U.S.C. § 103(a) as being unpatentable over
Neudecker et al. (US 2003/0064292 A1, published Apr. 3, 2003) in
view of Sugita as evidenced by Burgelman et al. (Modelling
polycrystalline semiconductor solar cells, 361–362 Thin Solid Films
527–532 (2000)).

REJECTIONS (1): WRITTEN DESCRIPTION
ISSUE
Did the Examiner reversibly err in finding that the subject matter of
claim 120 lacks written descriptive support because the Specification
discloses on page 57 that when polycrystalline silicon is used in the layers, a
depleted layer 512 is formed between the n-doped and p-doped layers, which
does not comport with what constitutes “circumferentially disposed” as that
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phrase is defined on pages 23–24 of the Specification? We decide this issue
in the affirmative.

FINDINGS OF FACT AND ANALYSES
The Examiner’s findings are located on pages 6 and 26 of the Answer.
The Examiner finds that there is no disclosure of a solar cell comprising a
first layer comprising p-doped polycrystalline silicon circumferentially
disposed on a second layer comprising n-doped polycrystalline silicon (Ans.
6). The Examiner finds that the only embodiment disclosed using
polycrystalline silicon includes a depleted polycrystalline layer between the
p-doped and n-doped polycrystalline layers (id.). The Examiner finds that
the depleted layer would preclude the first layer from being
circumferentially disposed on the second layer based upon the definition of
“circumferentially disposed” on pages 23–24 of the Specification (id.).
Appellants argue that the depletion layer disclosed on page 57 of the
Specification is not a separate layer (Br. 7). Rather, Appellants contend that
the depletion layer is a natural effect arising from the circumferential
disposition of the p-doped semiconductor onto the n-doped semiconductor.
Id. Appellants argue that the depletion layer forms due to the junction
between a p-type semiconductor and an n-type semiconductor. Id.
The test for sufficiency of the written description is whether the
disclosure of the application relied upon reasonably conveys to those skilled
in the art that the applicant had possession of the claimed subject matter as
of the filing date. In re Owens, 710 F.3d 1362, 1366 (Fed. Cir. 2013).
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In the present case, on page 57 of the Specification, Appellants cite
Bube,2 Photovoltaic Materials, 1998 Imperial College Press, London pages
57–66 as describing the p-n polycrystalline silicon junctions. Bube at page
60 discloses that a depletion region forms between a p-doped and n-doped
polycrystalline silicon junction. Moreover, Bube discloses on page 18 that
the p-doped and n-doped layers in a p-n junction are doped so that the
doping is the same so that the resulting depletion region has equal widths.
In light of these disclosures, we find that one of ordinary skill in the
art would have understood that the depletion layer is formed from the p-
doped region and n-doped region of the p-n junction as evinced by Bube.
Accordingly, we do not find that claim 120 lacks written descriptive support.
We reverse the Examiner’s § 112, first paragraph, rejection of claim 120.

REJECTIONS (2), (4), (7), (8), AND (9)
Appellants’ arguments focus solely on claim 1 (Br. 8–12, 16, 19).
The rejections of the dependent claims under rejections (2), (4), and (7) to
(9) will stand or fall with our analysis regarding the rejection of claim 1 over
Chittibabu and Gebeyehu.

ISSUE
Did the Examiner reversibly err in finding that one of ordinary skill in
the art would have modified Chittibabu’s solar cell to include Gebeyehu’s
poly(3-octylthiphene) or a low-bandgap thiophene-isothianaphthene-based
copolymer as the charge carrier material 415 in Chittibabu’s solar cell

2 The Bube reference including pages 1-277 was made of record in the
Information Disclosure Statement (IDS) filed May 4, 2006.
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because Chittibabu discloses using p-type conducting polymers for this layer
and Gebeyehu discloses that using solid-hole transfer materials simplify
construction and improve cell stability relative to liquid-electrolyte cells
(Ans. 11)? We decide this issue in the negative.

FINDINGS OF FACT & ANALYSIS
The Examiner finds that Chittibabu teaches that subject matter of
claim 1, except for, inter alia, the first layer (415 in Chittibabu’s Figure 4) of
the photovoltaic layer comprising a first semiconductor element (Ans. 8–10).
The Examiner finds that Gebeyehu teaches materials known to be useful for
charge transport from titanium dioxide electrodes to the counter electrode in
dye-sensitized cells, namely p-type polymeric semiconductors, such as
poly(3-octylthiphene) (P3OT) or a low bandgap thiophene-isothianaphthene-
based copolymer (Ans. 10). The Examiner finds that this function is the
same function required of layer 415 in the cell of Chittibabu’s Figure 4c. Id.
The Examiner concludes that it would have been obvious to modify
Chittibabu’s solar cell to include Gebeyehu’s poly(3-octylthiphene) or a
low-bandgap thiophene-isothianaphthene-based copolymer as the charge
carrier material 415 in Chittibabu’s solar cell because Chittibabu discloses
using p-type conducting polymers for this layer and Gebeyehu discloses that
using solid-hole transfer materials simplify construction and improve cell
stability relative to liquid-electrolyte cells (Ans. 11).
Appellants argue that one of ordinary skill would not have been
motivated to combine Gebeyehu’s P3OT or a thiophene-isothianaphthene-
based copolymer with Chittibabu’s solar cell because Gebeyehu teaches
away from the combination (Br. 9). Appellants contend that Gebeyehu
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would not have motivated one of ordinary skill in the art to use P3OT in a
solar cell because using P3OT decreases the efficiency of the cell which
would greatly outweigh the benefit of improved cell stability. Id.
Appellants contend that Gebeyehu’s disclosure that the efficiencies achieved
with a solar cell using P3OT are more than one order of magnitude smaller
than the efficiencies observed for devices with a liquid electrolyte as
transport medium (Br. 10–11). Appellants contend that Gebeyehu discloses
problems with using a polymeric hole conductor include imperfect
topological filling of the polymeric hole conductor into the pores between
the nanoparticles in such solar cells and adhesion of the polymer on the
titanium dioxide or the Ru dye in the solar cells (Br. 11).
The Examiner’s rejection is based upon substituting Gebeyehu’s
P3OT or a low-bandgap thiophene-isothianaphthene-based copolymer for
the charge material 415 in Chittibabu’s solar cell. As noted by the
Examiner, Chittibabu discloses using p-doped polymeric materials as the
charge carrying material 415 (Ans. 10). Gebeyehu discloses that using
liquid elecrolytes makes the manufacturing process more difficult because
the cells must be electrically connected yet chemically separated (Gebeyehu
280 top of first column). Gebeyehu discloses that it would be desirable to
substitute a solid hole conducting material for the liquid electrolyte to
eliminate problems with sealing and degradation. Id. Gebeyehu states that
“we demonstrate that conjugated semiconducting polymers can be
successfully adopted to [the] concept of nanocrystalline TiO2 solar cells,
replacing the electrolyte as well as the dye” (Gebeyehu 280 second column).
Gebeyehu discloses that the lower efficiency and imperfect topological
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filling of the polymeric hole conductor into the pores between nanoparticles
are challenges that remain to be solved (Gebeyehu 287).
Like the Examiner (Ans. 27), we find that one of ordinary skill in the
art would not have viewed Gebeyehu’s teachings as teaching away. “A
reference may be said to teach away when a person of ordinary skill, upon
reading the reference, would be discouraged from following the path set out
in the reference, or would be led in a direction divergent from the path that
was taken by the applicant.” In re Gurley, 27 F.3d 551, 553 (Fed. Cir.
1994). In the present case, the nature of Gebeyehu’s teaching is that
polymeric p-doped material may be used to make solar cells in a less
complicated manner than when liquid electrolyte is used, but with a trade-off
that less efficient solar cells may result. As noted by the Examiner, one of
ordinary skill in the art would have taken into consideration the lower
efficiency with the easier construction in determining the suitability of using
the polymer charge material in lieu of a liquid electrolyte for a particular
solar cell application. Appellants do not respond to this finding of the
Examiner (No Reply Brief filed).
On this record, we affirm the Examiner’s § 103 rejections (2), (4), (7),
(8), and (9).

REJECTION (3): § 103 Claim 3
Claim 3 is representative of the arguments advanced by Appellants
(Br. 12–15).

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ISSUE
Did the Examiner reversibly err in finding that one of ordinary skill in
the art would have used Sugita’s3 outer glass protective layer as Chittibabu’s
outer protective layer 424 in order to provide a strong layer to protect the
solar cell from water? We decide this issue in the negative.

FINDINGS OF FACT & ANALYSIS
The Examiner finds that the combined teachings of Chittibabu and
Gebeyehu teach the subject matter of claim 3, except for the use of glass as a
transparent tubular outer casing (Ans. 13). The Examiner finds that Sugita
discloses a cylindrical fiber solar cell, which is coated with a protective layer
7 of glass that is circumferentially disposed on the outer transparent
conductive layer 6, and which provides isolation from the atmosphere (id.).
The Examiner concludes that it would have been obvious to modify
Chittibabu’s solar cell by using a glass tubular casing for layer 424 as taught
by Sugita because glass possesses strength and water impermeability
required for such protective layers (id.).
Appellants argue that Sugita’s solar cell is completely inapposite to
Appellants’ claimed invention and Chittibabu’s solar cell (Br. 15).
Appellants contend that Sugita’s invention is directed to a different kind of
solar cell wherein a separate substrate and back electrode are not required

3 For reasons evident infra, we focus solely on the alterative rejection based
upon the combined teachings of Chittibabu, Gebeyehu. and Sugita. Because
we find that the Examiner’s rejection including Sugita is affirmable, we find
it unnecessary to reach the Examiner’s rejection based upon Chittibabu in
view of Gebeyehu and Nakata.
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and thus the presence or absence of a transparent tubular casing comprising
glass would have had no import to one skilled in the art. Id.
Appellants have not explained why the differences in solar cell
structure would have led one of ordinary skill to the conclusion that the
presence or absence of a transparent tubular casing would have had no
import. Rather, both Sugita and Chittibabu teach using protective outer
layers 7 and 424, respectively, on flexible solar cells. We find that Sugita
would have suggested using glass as a protective layer in a solar cell.
Indeed, Sugita discloses that the fiber solar cells may be flexed without
damage to the solar cell and these fibers may be woven using a loom (Sugita
¶ [0017]). Chittibabu discloses that the photovoltaic fibers may be woven
into a flexible fabric (Chittibabu ¶ [0079]). Based on these teachings, we
agree with the Examiner that the combined teachings of Chittibabu and
Sugita would have suggested using glass material as the outer protective
layer on a flexible solar cell.
We affirm the Examiner’s § 103 rejection over Chittibabu in view of
Gebeyehu and Sugita.

REJECTION (5): Claim 34
ISSUE
Did the Examiner reversibly err in finding that the combined
teachings of Chittibabu, Gebeyehu, and Mlavsky would have suggested an
antireflective coating circumferentially disposed on the transparent tubular
casing as recited in claim 34? We decide this issue in the negative.

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FINDINGS OF FACT & ANALYSIS
Claim 34 recites: “[t]he solar cell unit of claim 1, the solar cell unit
further comprising an antireflective coating circumferentially disposed on
said transparent tubular casing.”
The Examiner finds that Chittibabu and Gebeyehu fail to teach an
antireflective coating on protective layer 424 (Ans. 15). The Examiner finds
that Mlavsky teaches providing an antireflective coating on the outer surface
of a protective tube containing solar cells to increase light transmission to
the solar cells (id.). The Examiner concludes that it would have been
obvious to modify Chittibabu’s solar cell by providing an antireflective
coating on the protective layer as taught by Mlavsky because it would have
increased the amount of light incident on the photoactive junction, thereby
increasing the power output from the cell (Ans. 15).
Appellants argue that Mlavsky’s rigid envelope 16 with the
antireflective coating is not circumferentially disposed on the solar cell (Br.
16). Appellants contend that Mlavsky’s teachings would not have suggested
that an antireflective coating could have been added to the flexible fibers of
Chittibabu (Br. 17). Appellants argue that Mlavsky’s application of an
antireflective coating to a rigid glass envelope 16 would not have suggested
overlaying an antireflective coating on the fibers of Chittibabu. Id.
Appellants contend that there is no indication that Mlavsky’s antireflective
coating may be used with Chittibabu’s dye sensitized solar cells. Id.
Contrary to Appellants’ arguments, the Examiner finds that Mlavsky
teaches that it is beneficial to apply an antireflective coating to increase light
transmission to the solar cells. Appellants’ arguments do not specifically
refute that finding. Rather, Appellants’ arguments merely allege that
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Mlavsky’s antireflective coating would not have been compatible with
Chittibabu’s solar cell. Appellants have not proffered any evidence to
substantiate the mere attorney argument. Moreover, the Examiner is not
suggesting that Mlavsky’s antireflective coating would have been added to
Chittibabu’s solar cell. Instead the Examiner finds that one of ordinary skill
in the art would have found it desirable to add an antireflective coating to the
outer cover of a solar cell to increase light transmission. In other words, the
Examiner appears to be using Mlavsky to demonstrate what would have
been known in the art and within the skill of the ordinary artisan to
implement.
On this record, we affirm the Examiner’s § 103 rejection of claim 34.

REJECTION (6): Claim 35
Claim 35 recites: “[t]he solar cell unit of claim 34, wherein the
antireflective coating comprises MgF2, silicon nitrate, titanium nitrate,
silicon monoxide, or silicon oxide nitrite.”
The Examiner finds that the combined teachings of Chittibabu,
Gebeyehu, and Mlavsky teach the subject matter of claim 35, but the
Examiner finds that Mlavsky fails to teach the composition of the
antireflective coating (Ans. 16). The Examiner finds that Baumeister
teaches using a magnesium fluoride antireflective coating on a solar cell
(id.). The Examiner concludes that it would have been obvious to modify
the solar cell suggested by Chittibabu as modified by Gebeyehu and
Mlavsky by using the magnesium fluoride antireflective coating as taught by
Baumeister because Baumeister teaches the effectiveness in reducing the
reflection of solar radiation by using an antireflective coating (id.).
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Appellants argue that the applied prior art, either alone or in
combination, fails to provide a reasonable expectation of success that any of
the materials recited in claim 35 may be used on Chittibabu’s fibers as an
antireflective coating (Br. 18). Appellants contend that Chittibabu’s fibers
are flexible and there is no teaching or expectation that any of the claimed
antireflective coatings of Baumeister may be used on Chittibabu’s flexible
fibers while still permitting Chittibabu’s fibers to achieve their intended
purpose: solar cells that may be woven into a fabric (id.). Appellants further
contend that there is no teaching in any of the references that an
antireflective coating is compatible with, Chittibabu’s dye sensitized solar
cells (id.).
The Examiner finds that Appellants’ argument that there is no
reasonable expectation of success for forming an antireflection coating on a
flexible substrate is lacking evidence (Ans. 30). Appellants assert that there
would be no reasonable expectation of success, but Appellants fail to cite to
any portion of the applied prior art or other evidence to establish that there
would have been no reasonable expectation of success for forming an
antireflective coating on a flexible substrate. In our view, the Examiner has
provided evidence via the applied prior art that there is a reasonable
expectation that antireflective coatings on solar cells, which includes flexible
solar cells, would have been formed successfully. Appellants’ mere attorney
argument does not specifically address this evidence.
In response to Appellants’ argument that there is no teaching that an
antireflective coating is suitable for the dye-sensitized solar cells of
Chittibabu, the Examiner finds that the antireflective coating would have
permitted more light to enter the solar cell, which would have increased the
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efficiency regardless of the type of solar cell (Ans. 31). We agree. The
Examiner proposes placing the antireflective coating on the outside of the
casing 424 of Chittibabu (Ans. 30). Accordingly, the antireflective coating
would not come into contact with any of the other components of
Chittibabu’s solar cell. Moreover, the Examiner’s finding that the
antireflective coating would have resulted in more light entering the solar
cell and increasing efficiency is not contested by Appellants (no Reply
Brief).
On this record, the preponderance of the evidence favors the
Examiner’s conclusion that claim 35 would have been obvious over the
combined teachings of Chittibabu, Gebeyehu, Mlavsky, and Baumeister.

REJECTION (10): Claims 91 and 92
Claim 91 recites: “[t]he solar cell unit of claim 1, wherein the
transparent conductive layer is coated with a fluorescent material.” Claim
92 recites: “[t]he solar cell unit of claim 1, wherein a luminal or an exterior
surface of said transparent tubular casing is coated with a fluorescent
material.”
The Examiner finds that Chittibabu in view of Gebeyehu teaches the
subject matter of claims 91 and 92, except for providing a fluorescent
material over the transparent conducting layer or on the outer tubular casing
(Ans. 21). The Examiner finds that Trupke teaches efficiency gains are
achieved by adding a phosphorescent material as a luminescent converter for
down-conversion of high-energy photons impacting a photovoltaic device
and providing this fluorescent layer on the front of the cell (id.). The
Examiner concludes that it would have been obvious to modify the device of
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Chittibabu by providing a down-conversion layer on the front surface of the
solar cell as taught by Trupke because Trupke teaches that overall cell
efficiency is increased, due to overall better utilization of high-energy
photons resulting from application of such a layer (id.).
Appellants argue that Trupke’s solar cell operates by a different
mechanism than Chittibabu’s solar cell such that there would have been no
expectation that Trupke’s luminescence converter would improve the
efficiency of the device formed by the combination of Chittibabu and
Gebeyehu (Br. 20). Appellants contend that the device proposed by the
combination of Chittibabu and Gebeyehu does not generate photovoltaic
current from the absorption of light by a semiconductor in a semiconductor
junction, such that there is no teaching in any of the references that the dye
utilized in the combination of Chittibabu and Gebeyehu would benefit from
the down-converted photons of Trupke (Br. 20).
Appellants’ arguments attack the references individually instead of
addressing what the combined teachings would have suggested to one of
ordinary skill in the art. In re Keller, 642 F.2d 413, 425 (CCPA 1981).
While Chittibabu uses a dye-sensitized solar cell (DSSC), the Examiner
proposes substituting Gebeyehu’s P3OT polymer for the charge carrier
material in Chittibabu. Gebeyehu discloses a hybrid solar cell that uses both
solid state and dye-sensitized components (Gebeyehu abstract).
Accordingly, Appellants’ arguments regarding the different types of solar
cells are not persuasive because the combination uses a solid state p-n
junction too. Appellants have not established that Chittibabu’s solar cell as
modified by Gebeyehu that includes a solid state component would not have
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benefited from the use of Trupke’s fluorescent material for the reasons found
by the Examiner.
On this record, we affirm the Examiner’s § 103 rejection of claims 91
and 92 over Chittibabu, Gebeyehu, and Trupke.

REJECTION (11): Claims 102 and 104
Appellants argue claims 102–104, and 107–109 as a group (Br. 22–
23). We select claims 102 and 104 as representative.
The Examiner finds that Chittibabu as modified by Gebeyehu, Nakata
teaches the subject matter of claims 102 and 104, but the applied prior art
fails to teach applying an ultraviolet (UV) protective coating to the
transparent tubular casing (claim 102) or where the transparent tubular
casing is made of glass with additives and wherein the transparent tubular
casing provides complete protection from UV wavelengths (claim 104)
(Ans. 21). The Examiner finds that Beauchamp or Thelen teaches solar cell
covers that reflect nearly all UV light to reduce the amount of light that is
converted to heat in the solar cell (Ans. 22). The Examiner concludes that it
would have been obvious to modify the device of Chittibabu by providing a
highly UV- reflective coating to reflect portions of the UV spectrum that
provide little or no photo response over the protective layer as taught by
Beauchamp or Thelen because this would reduce deleterious heating of the
solar cell and thereby increase solar cell efficiency (id.).
Referring to page 663 of reference C13 to Luque cited on the
Information Disclosure Statement filed May 3, 2006, Appellants argue that
the dye-sensitized solar cells cannot absorb visible light due to their
relatively wide band gaps (Br. 23). Appellants contend that any
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modification of Chittibabu or Gebeyehu to include a UV-reflective coating
would severely limit absorption efficiency of the Chittibabu and/or
Gebeyehu absorbers (id.). Based upon these arguments, Appellants contend
that modifying Chittibabu’s solar cell to include Beauchamp’s or Thelen’s
UV-reflective coating would have severely limited the absorption efficiency
of the Chittibabu and/or Gebeyehu absorbers (id.).
While Appellants’ cite to page 663 of the Luque reference to support
their position that the proposed modification would severely limit the
absorption efficiency, our review of Luque reveals that there is no page 663
in the document (only pages 1-662 are included). Accordingly, Appellants’
have not directed us to any evidence to substantiate their argument that
stable oxide semiconductors used in dye-sensitized solar cells cannot absorb
visible light due to their relatively wide band gaps.
The Examiner reasonably finds that providing a UV-reflective coating
would provide the beneficial result of avoiding deleterious heating of the
solar cell. Appellants do not dispute this reason for the modification of
Chittibabu.
On this record, we affirm the Examiner’s § 103 rejection of claims
102–104 and 107–109 over Chittibabu in view of Gebeyehu, Nakata,
Beauchamp or Thelen.

REJECTION (12): Claim 1: Neudecker in view of Sugita
The Examiner finds that Neudecker teaches all the limitations of claim
1, except for a transparent tubular casing circumferentially disposed on the
solar cell (Ans. 22–23). The Examiner finds that Sugita teaches a cylindrical
solar cell having a glass protective layer 7 disposed on the solar cell to
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protect the solar cell from the atmosphere (Ans. 23). The Examiner
concludes that it would have been obvious to modify Neudecker’s solar cell
by providing a protective glass coating as taught by Sugita to protect the
sensitive photovoltaic layers from the atmosphere (Ans. 23).
Appellants argue that Neudecker’s solar cells do not need a protective
layer and adding such a layer would have added unnecessary expense to the
manufacture of Neudecker’s solar cells (Br. 24). Appellants further contend
that other researchers have used a transparent conductive layer as the
protective layer rather than adding a tubular casing (Br. 24).
The Examiner finds that Sugita teaches placing a tubular glass
protective layer over a doped tin oxide layer to provide protection (Ans. 33).
The Examiner finds that Neudecker, like Sugita, teaches using a doped tin
oxide as the transparent conductive oxide over the solar cell. Id. The
Examiner reasons that one of ordinary skill in the art would have adapted the
protective layers for the similar solar cells to suit the particular environment
where the solar cell will be used. Id. Appellants do not respond or
otherwise show error in these reasonable findings of the Examiner.
Appellants’ citation to a list of patents where no tubular protective layer was
used is not dispositive. In any event, Appellants concede that the art is
replete with solar cells having transparent conductors and further external
protective layers (Br. 24). This admission further supports the Examiner’s
finding that one of ordinary skill in the art would have determined the
appropriate protection, including adding tubular protective layer
circumferentially disposed on the solar cell, required for the solar cell in a
particular environment.
Appeal 2012-010068
Application 11/378,847

20
On this record, we affirm the Examiner’s § 103 rejection of claims 1–
3, 6, 9–13, 15, 16, 43–45, 88, 89, 96, 97, and 100 over Neudecker in view of
Sugita.

DECISION
The Examiner’s decision is affirmed-in-part.

TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
ORDER
AFFIRMED-IN-PART

cdc