DETAILED ACTION
Email Communication
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Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendment
Applicant’s amendment of 10/16/2023 does not place the Application in condition for allowance.
Claims 1-3 and 5-18 are currently pending. In response to Office Action mailed on 04/14/2023, Applicant has amended claims 1, 8 and 16.
Status of the Rejections
Due to Applicant’s amendment of claims 1, 8 and 16, all rejections from the Office Action mailed on 04/14/2023 are withdrawn. However, upon further consideration, a new ground of rejection is presented below.
Claim Interpretation
Instant claim requires a Pt layer, and further requires a metal contacts composed of Pt (claim 2 or 9). Therefore, there is no distinction between Pt layer and the metal contacts made of Pt. For the examination purpose, if the rear/back electrode/contact is made of Pt, part of the layer (upper portion) would be interpreted to read on Pt layer, and remaining part of the layer (lower part) would be interpreted to read on metal contacts.
Instant claim requires a Pt layer, and further requires a metal contacts, which can be composed of Pt (claim 15 or 17). Therefore, there is no distinction between Pt layer and the metal contacts made of Pt. For the examination purpose, if the rear/back electrode/contact is made of Pt, part of the layer (upper portion) would be interpreted to read on Pt layer, and remaining part of the layer (lower part) would be interpreted to read on metal contacts.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 3, 5-8, 10-14, 16 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Flood (US 2011/0220191 A1) in view of Lu et al. (US 2008/0308147 A1).
Regarding claims 1, 8 and 11, Flood discloses a solar cell (photovoltaic device 100, fig. 1, [0082-0108]), comprising:
an n-doped CdS layer (window layer 106, which is made of CdS, fig. 1 and [0097]);
a p-doped group II-VI or CdTe layer (region 132 of absorption layer 104, wherein absorption layer includes CdTe that is doped with p-type dopant, fig. 1 and [0097]) substantially covering the n-doped CdS layer (see fig. 1);
a graphene layer (mesh 124 that includes graphene sheets 122, [0084] and [0100]) substantially covering the CdTe layer (132) on a side (bottom side) opposite the n-doped CdS layer (106) (see fig. 1 for configuration); and
metal contacts (back electrical contact 102 that is made of metal such as Al or Cu, [0091]) on the graphene layer (124) on the side (bottom side) opposite the p-doped CdTe layer (132) (see fig. 1 for configuration).
Flood further discloses the metal contacts (102) is disposed on a substrate (101) (see fig. 1), which can for example be made of glass ([0091]). Flood further discloses that the metal contacts or back electrical contact (102) can have textured surface in order to improve anchoring of the carbon nanotubes (122) ([0090]). However, Flood does not disclose a back electrical contact (102) comprising a platinum or molybdenum oxide layer substantially covering the graphene layer on a side opposite the p-doped CdTe layer, and metal contacts on the graphene layer on a side opposite the p-doped CdTe layer.
Lu discloses a CdS/CdTe based solar cell (fig. 1a, 3b-3d[0028]) wherein a rear electrode (10, fig. 1a and 3a, [0029-0033] and [0051]) is deposted on a glass substrate (11). Lu further discloses that the rear electrode (10) comprises a first layer (10b) including an oxide of Mo (MoOx) and a second layer (10c) comprising an oxide of Mo (MoOy) (fig. 3b, [0051]). In an alternative embodiment, Lu discloses the rear electrode (10) comprises a Mo layer (10c), a MoOx layer (10b) and Cr layer (10d) (fig. 4). Lu further discloses that the rear electrode is textured and oxidation graded to promote adhesion ([0006]) and also to reflect incident light more effectively and efficiently into the semiconductor film ([0015]).
Therefore, it would have been obvious to one skilled in the art at the time of the invention to have used the rear electrode (as shown in fig. 3b or 4) of Lu to form the back electrical contacts of Flood such that adhesion between layers is promoted, as shown by Lu and also desired by Flood, and also to reflect incident light more effectively and efficiently into the semiconductor film, as shown by Lu.
Thus, Flood as modified by Lu discloses a molybdenum oxide layer (Lu: fig. 3b, 10c made of MoOy) substantially covering the graphene layer (124 of Flood) on a side (bottom side) opposite the p-doped CdTe layer (132 of Flood), and metal contacts (Lu: fig. 3b, 10b made of MoOx) on the graphene layer (124) on the side (bottom side) opposite the p-doped CdTe layer (132 of Flood).
Alternatively, Flood as modified by Lu discloses a molybdenum oxide layer (Lu: fig. 4, 10b made of MoOx) substantially covering the graphene layer (124 of Flood) on a side (bottom side) opposite the p-doped CdTe layer (132 of Flood), and metal contacts (Lu: fig. 4, 10d made of Cr) on the graphene layer (124) on a side (bottom side) opposite the p-doped CdTe layer (132 of Flood). Note that instant claim does not preclude the presence of Mo layer (10c, fig. 4 of Lu) between graphene layer (layer 124 of Flood) and the molybdenum oxide layer (10b, fig. 4 of Lu).
It is further noted that there is no material or structural difference between the platinum or molybdenum covered graphene layer of Flood as modified by Lu and that of the instant claim, and between p-doped CdTe layer of Flood as modified by Lu and that of the instant claim.
A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present. See MPEP §2112.01 (II).
Thus, the platinum or molybdenum covered graphene layer of Flood as modified by Lu must have a lower work function that the work function of the p-doped CdTe layer of Flood as modified by Lu, as in the case of the instant application.
Regarding claims 3 and 10, Flood as modified Lu further discloses that the metal contacts are composted of molybdenum oxide (Lu: fig. 3b, 10c made of MoOy).
Regarding claims 5 and 12, Flood further discloses a conducting oxide layer (top electrical contact 108 that includes metal oxide, [0092], and radiation-transparent) substantially covering the CdS layer (106) on a side (top side) opposite the p-doped CdTe layer (see fig. 1).
Regarding claims 6 and 13, Flood further discloses that the conducting oxide layer is composed of metal oxide ([0092]). However, Flood does not explicitly disclose that the metal oxide is SnO2:F.
Lu is directed to the same field of endeavor, namely solar or photovoltaic art, as Flood, wherein top contact or electrode is made of metal oxide such as fluorine-doped tin oxide ([0046]). Thus, Lu discloses that SnO2:F is a known metal oxide material that can be used a transparent conducting oxide material to form a top contact or electrode of a solar cell.
Therefore, it would have been obvious to one skilled in the art at the time of the invention to have used the SnO2:F as taught by Lu to form the conducting oxide layer of Flood because selection of a known material based on its suitability for its intended use supported a prima facie obviousness determination in Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945). See MPEP § 2144.07.
Regarding claims 7 and 14, Flood does not disclose a glass layer substantially covering the conducting oxide layer (108) on a side opposite the n-doped CdS layer.
Lu is directed to the same field of endeavor, namely solar or photovoltaic art, as Flood, wherein a glass layer (front glass sheet 1) substantially covers the conductive oxide layer (3, [0046]).
Therefore, it would have been obvious to one skilled in the art at the time of the invention to have used the glass layer as taught by Lu on top of the transparent conductive oxide layer such that glass layer can function as a support for other layers, as shown by Lu.
Regarding claims 16 and 18, Flood as modified by Lu further discloses the Pt or molybdenum oxide layer is a molybdenum oxide layer (Lu: 10c of figure 3b that made of MoOy or layer d of fig. 4 that is made of MoOx).
Claims 2 and 9 are rejected under 35 U.S.C. 103 as being unpatentable over Flood (US 2011/0220191 A1) in view of Lu et al. (US 2008/0308147 A1) as applied above, and further in view of Murata et al. (US 2012/0143544 A1).
Regarding claims 2 and 9, Flood as modified by Lu discloses that the metal contacts are composed of Cr (see fig. 4 of Lu). However, Flood as modified by Lu is silent as to whether the metal contacts are made of Pt (fig. 4 of Lu).
Murata is directed to a solar cell wherein metal contacts for solar cell is made of Pt or Cr ([0082]). Thus, Murata explicitly disclose that Cr and Pt are art-recognized equivalent metal contact materials that can be use used to form metal contact of solar cell.
Therefore, it would have been obvious to one skilled in the art at the time of the invention to have used substituted Cr metal contacts of Flood in view of Lu with Pt metal contacts of Murata because simple substitution of one known element for another to obtain predictable result is obvious (KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007)) (MPEP §2143).
Claims 1-2, 5, 8-9, 11-12, 15 and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Flood (US 2011/0220191 A1) in view of Murata et al. (US 2012/0143544 A1).
Regarding claims 1-2, 8-9 and 11, Flood discloses a solar cell (photovoltaic device 100, fig. 1, [0082-0108]), comprising:
an n-doped CdS layer (window layer 106, which is made of CdS, fig. 1 and [0097]);
a p-doped group II-VI or CdTe layer (region 132 of absorption layer 104, wherein absorption layer includes CdTe that is doped with p-type dopant, fig. 1 and [0097]) substantially covering the n-doped CdS layer (see fig. 1);
a graphene layer (mesh 124 that includes graphene sheets 122, [0084] and [0100]) substantially covering the CdTe layer (132) on a side (bottom side) opposite the n-doped CdS layer (106) (see fig. 1 for configuration); and
back electrical contact (102) ([0091]) on the graphene layer (124) on a side (bottom side) opposite the p-doped CdTe layer (132) (see fig. 1 for configuration).
Flood further discloses that the back contact (102) is composed, for example, of metal contact such as Al or Cu ([0091]). Those one skilled in the solar or photovoltaic art realizes that the back contacts are limited to the materials listed by Flood. Further note that disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971) (MPEP §2123).
However, Flood is silent as to whether the metal contacts are made of Pt.
Murata is directed to a solar cell wherein metal contacts for solar cell is made of Al, Cu and Pt ([0082]). Thus, Murata explicitly disclose that Al/Cu and Pt are art-recognized equivalent metal contact materials that can be use used to form metal contact of solar cell.
Therefore, it would have been obvious to one skilled in the art at the time of the invention to have used substituted Al/Cu metal contacts of Flood with Pt metal contacts of Murata because simple substitution of one known element for another to obtain predictable result is obvious (KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007)) (MPEP §2143).
Instant claim requires a Pt layer, and further requires a metal contacts which can be composed of Pt (claim 2 or 9). Therefore, there is no distinction between Pt layer and the metal contacts made of Pt. For the examination purpose, if the rear/back electrode/contact is made of Pt, part of the layer (upper portion) would be interpreted to read on Pt layer, and remaining part of the layer (lower part) would be interpreted to read on metal contacts. Flood as modified by Murata discloses that the rear/back electrode/contact is made of Pt. Accordingly, part of the layer (upper portion) is interpreted to read on Pt layer, and remaining part of the layer (lower part) is interpreted to read on metal contacts.
Accordingly, Flood as modified by Murata discloses a Pt layer (upper part of Pt layer) substantially covering the graphene layer (124 of Flood) on a side (bottom side) opposite the p-doped CdTe layer (132 of Flood), and metal contacts (lower part of Pt layer) on the graphene layer (124) on a side (bottom side) opposite the p-doped CdTe layer (132 of Flood).
It is further noted that there is no material or structural difference between the platinum covered graphene layer of Flood as modified by Lu and that of the instant claim, and between p-doped CdTe layer of Flood as modified by Lu and that of the instant claim.
A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present. See MPEP §2112.01 (II).
Thus, the platinum covered graphene layer of Flood as modified by Lu must have a lower work function that the work function of the p-doped CdTe layer of Flood as modified by Lu, as in the case of the instant application.
Regarding claims 2 and 9, Flood as modified by Murata discloses that the metal contacts are composed of Pt (lower part of Pt layer).
Regarding claims 5 and 12, Flood further discloses a conducting oxide layer (top electrical contact 108 that includes metal oxide, [0092], and radiation-transparent) substantially covering the CdS layer (106) on a side (top side) opposite the p-doped CdTe layer (see fig. 1).
Regarding claims 15 and 17, Flood as modified by Murata discloses that the Pt layer or molybdenum oxide layer is a Pt layer (upper part of Pt layer).
Response to Arguments
Applicant's arguments with respect to claims 1-3 and 5-14 have been considered but are moot in view of the new ground(s) of rejection as necessitated by the amendments.
Applicant argues that Flood as modified fails to disclose that the platinum or molybdenum covered graphene layer has low work function that the p-doped CdTe layer.
The examiner respectfully disagrees. There is no material or structural difference between the platinum or molybdenum covered graphene layer of Flood as modified and that of the instant claim, and between p-doped CdTe layer of Flood as modified and that of the instant claim (see Above). A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present. See MPEP §2112.01 (II). Thus, the platinum or molybdenum covered graphene layer of Flood as modified must have a lower work function that the work function of the p-doped CdTe layer of Flood as modified, as in the case of the instant application.
Applicant further argues that the combination is based on hindsight reasoning.
The examiner respectfully disagrees. In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
Applicant further argues that the references does not disclose any benefit in regards to the work function of the layers.
In response to applicant's argument that with respect to the work function, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. US 2020/0343403 A1 to Heben et al. discloses solar cell (10, fig. 1) a graphene layer (interface layer 20 that includes graphene, [0058]) over p-type CdTe layer (18) ([0050]), and a metal contact layer (back contact 22 that is made of Au, see figure 4 or 5) over the graphene layer (20).
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the date of this final action.
Correspondence/Contact Information
Any inquiry concerning this communication or earlier communications from the examiner should be directed to GOLAM MOWLA whose telephone number is (571)270-5268. The examiner can normally be reached on M-Th, 7am - 4pm.
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/GOLAM MOWLA/Primary Examiner, Art Unit 1721