DETAILED ACTION
This is the first office action for 18/035,026, filed 5/2/2023, which is a national stage entry of PCT/US2021/057867, filed 11/3/2021, which claims priority to provisional application 63/109,261, filed 11/3/2020, after the request for continued examination filed 1/26/2026.
Claims 1-8, 11-15, 19-20, 22, 24, and 28-30 are pending; Claims 11-15, 19-20, 22, 24, and 28- 30 are considered herein.
In light of the IDS filed 2/2/2026, the prior art rejections are withdrawn, and new grounds of rejection are presented herein.
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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 1/26/2026 has been entered.
Additional Prior Art
The Examiner wishes to apprise the Applicant of the following references, which are not currently applied in a rejection.
U.S. Patent Application Publication 2014/0038392 A1: This reference teaches a method of forming a solar cell, comprising the formation of via holes via a laser (paragraph [0114]).
U.S. Patent Application Publication 2015/0179865 A1: This reference teaches a method of forming a solar cell, comprising the formation of via holes via a laser (Fig. 11, paragraph [0064]).
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 11-12, 14, 19-20, 22, 24, and 28-30 are rejected under 35 U.S.C. 103 as being unpatentable over Kiyama, et al. (U.S. Patent ) in view of Moslehi, et al. (U.S. Patent Application Publication 2012/0305063 A1).
In reference to Claim 11, Kiyama teaches a method for forming a photovoltaic device (Figs. 7 and 11(a)-(b), column 8, line 38-column 9, line 15).
The method of Kiyama comprises forming a first conducting layer 3 over a semiconductor stack 1/2 comprising an absorber layer 2 (column 8, lines 38-45).
Kiyama teaches that the first conducting layer 3 has a layer thickness (Figs. 7 and 11), and is configured to provide electrical contact with the absorber layer 2 (column 8, lines 40-45).
The method of Kiyama comprises forming a dielectric layer 4 over the first conducting layer 3, wherein the dielectric layer has a dielectric layer thickness (column 8, lines 47-50).
The method of Kiyama comprises heating an affected region of the first conducting layer 3 with a laser pulse (i.e. Q-switching YAG laser, column 8, lines 49-67).
The method of Kiyama comprises melting (i.e. ablating) the affected region of the first conducting layer 3, whereby a contact region is formed in the first conducting layer 3 and a portion of the dielectric layer 4 disposed over the affected region of the first conducting layer 3 is delaminated to define a via through the portion of the dielectric layer 4 (Fig. 11(b), column 8, line 49, through column 9, line 14).
Kiyama teaches that the contact region of the first conducing layer has a flat and annular shape (column 8, lines 50-55).
The method of Kiyama comprises forming a conducting layer interconnect 5 through the via of the dielectric layer and in contact with the contact region of the first conducting layer 3 (i.e. in electrical contact with layer 3 via layers 1 and 2, and in thermal and structural contact with layer 3) (Fig. 7, column 8, lines 54-57).
Kiyama teaches that the thickness of the first conducting layer 3 is 1000 Å (column 6, lines 59-60).
Kiyama is silent regarding the thickness of the dielectric layer 4.
Therefore, he does not teach that a ratio of the dielectric layer thickness to the conducting layer thickness is at least 10:1. However, he teaches that the dielectric layer 4 is SiO2 (column 5, line 10).
To solve the same problem of laser-patterning solar cells, Moslehi teaches that the thickness of a silicon oxide layer deposited as a protective layer prior to laser patterning should be controlled to be thin enough to be easily patterned by laser ablation, while thick enough to block diffusion of materials into the areas covered by the insulating layer (paragraph [0066]).
Therefore, absent a showing of persuasive secondary considerations, it would have been obvious to one of ordinary skill in the art at the time the instant invention was filed to have selected the thickness of the SiO2 dielectric layer of Kiyama to be thin enough to be easily patterned by laser ablation, while thick enough to block diffusion of materials into the areas covered by the insulating layer, based on the teachings of Moslehi.
Further, it is the Examiner’s position that this routine optimization would have led one of ordinary skill in the art to have arrived at the claimed range of “a ratio of the dielectric layer thickness to the conducting layer thickness is at least 10:1,” without undue experimentation.
In reference to Claim 12, Kiyama teaches that the conducting layer interconnect is formed by depositing a second conducting layer 5 over the dielectric layer 4 (Fig. 7, column 8, lines 54-57).
In reference to Claim 14, Kiyama teaches that the laser pulse of the method of his invention has a Gaussian shape (column 6, lines 67-68).
In reference to Claim 19, Kiyama does not teach that the solar cell of his invention necessarily has a structure that meets the limitations of Claim 19.
However, he teaches an embodiment (Fig. 16, column 10, lines 53-68) in which a solar cell with a width of 10 cm comprises contact holes with radii between 0.1-0.55 mm (i.e. 0.01-0.055 cm).
This results in a ratio of a maximum thickness of the first conducting layer 3 (i.e. 10 cm) to a surface area of a contact region of the first conducting layer of 31,847:1 (for r = 0.1 mm) to 1053:1 (for r = 0.55 mm).
Therefore, absent a showing of persuasive secondary considerations, it would have been obvious to one of ordinary skill in the art at the time the instant invention was filed to have structured the solar cell of Kiyama to have the dimensions and contact area radii described in relation to his Fig. 16, because he teaches that these are suitable forms of the solar cells of his invention.
Structuring the solar cell of Kiyama to have the dimensions and contact area radii described in relation to his Fig. 16 teaches the limitations of Claim 19, wherein a ratio of the maximum thickness of the first conducting layer to the surface area of the contact region is at least 750:1 (i.e. 31,847:1 (for r = 0.1 mm) to 1053:1).
In reference to Claim 20, Fig. 7 of Kiyama teaches that the conducting layer interconnect 5 is bounded by a via wall of the dielectric layer 4.
Fig. 7 of Kiyama further teaches that an interface angle (i.e. 90°) is defined by the via wall of the dielectric layer 4 and the contact region of the first conducting layer 3, and the interface angle Θ is larger than 75° (i.e. 90°).
In reference to Claim 22, Kiyama does not teach that the semiconductor stack necessarily comprises a back contact layer over the absorber layer.
However, he teaches that one of several suitable configurations for the absorber layer of his invention includes a pin amorphous silicon junction layer and a pn polycrystalline silicon layer, with the pin junction layer disposed on the light receiving side of the device (i.e. the bottom of the device in Figs. 11 and 7, column 5, line 58, through column 6, line 5).
Therefore, absent a showing of persuasive secondary considerations, it would have been obvious to one of ordinary skill in the art at the time the instant invention was filed to have formed the semiconductor stack of Kiyama to have a tandem structure comprising a pin amorphous silicon junction as the “bottom” portion of layer 2 in Figs. 7 and 11, and a pn polycrystalline junction as the “top” portion of layer 2 in Figs. 7 and 11, because Kiyama teaches that this is a suitable configuration of the device of his invention.
Forming the semiconductor stack of Kiyama to have a tandem structure comprising a pin amorphous silicon junction as the “bottom” portion of layer 2 in Figs. 7 and 11, and a pn polycrystalline junction as the “top” portion of layer 2 in Figs. 7 and 11 teaches the limitations of Claim 22, wherein the semiconductor stack comprises a back contact layer over the absorber layer, corresponding to the pn polycrystalline silicon layer. It is noted that claim 22 does not require that the “back contact layer” have any specific composition.
Forming the semiconductor stack of Kiyama to have a tandem structure comprising a pin amorphous silicon junction as the “bottom” portion of layer 2 in Figs. 7 and 11, and a pn polycrystalline junction as the “top” portion of layer 2 in Figs. 7 and 11 teaches the limitations of Claim 22, wherein the first conducting layer 3 is over the back contact layer.
In reference to Claim 24, Kiyama teaches that the thickness of the first conducting layer 3 is 1000 Å, i.e. 100 nm (column 6, lines 59-60).
This disclosure teaches the limitations of Claim 24, wherein a thickness of the first conducting layer 3 is between about 50 nm to about 2.5 microns (i.e. 100 nm).
In reference to Claim 28, Kiyama teaches that the first conducting layer 3 has a composition of aluminum or titanium (column 6, lines 57-60) and the second conducting layer 5 has a composition of nickel or silver (column 7, lines 34-35).
This disclosure teaches the limitations of Claim 28, wherein the first conducting layer 3 and the second conducting layer 5 have different material composition.
In reference to Claim 29, Fig. 7 teaches that the conducting layer interconnect 5 directly contacts the semiconductor stack 1/2.
In reference to Claim 30, Kiyama does not teach that the solar cell of his invention necessarily has a structure that meets the limitations of Claim 30.
However, he teaches an embodiment (Fig. 16, column 10, lines 53-68) in which a solar cell with a width of 10 cm comprises contact holes with radii between 0.1-0.55 mm (i.e. 0.01-0.055 cm).
This results in a ratio of a maximum thickness of the first conducting layer 3 (i.e. 10 cm) to a surface area of a contact region of the first conducting layer of 31,847:1 (for r = 0.1 mm) to 1053:1 (for r = 0.55 mm).
Therefore, absent a showing of persuasive secondary considerations, it would have been obvious to one of ordinary skill in the art at the time the instant invention was filed to have structured the solar cell of Kiyama to have the dimensions and contact area radii described in relation to his Fig. 16, because he teaches that these are suitable forms of the solar cells of his invention.
Structuring the solar cell of Kiyama to have the dimensions and contact area radii described in relation to his Fig. 16 teaches the limitations of Claim 30, wherein a ratio of the maximum thickness of the first conducting layer to the surface area of the contact region is in a range from 750:1 to 1500:1 (i.e. 31,847:1 (for r = 0.1 mm) to 1053:1).
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. See MPEP 2144.05 I.
In the instant case, the claimed range of 750:1 to 1500:1” overlaps with the taught range of 1053:1 to 31,847:1.
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Kiyama, et al. (U.S. Patent ) in view of Moslehi, et al. (U.S. Patent Application Publication 2012/0305063 A1), and further as evidenced by Wang (U.S. Patent Application Publication 2008/0080050 A1).
In reference to Claim 13, Kiyama teaches that the dielectric layer of his invention is SiO2 (column 5, line 10).
Evidentiary reference Wang teaches that SiO2 has a transmission rate of about 90% at wavelengths between 1-2 microns (Wang, Fig. 10, paragraph [0041]).
Therefore, the dielectric layer has greater than 10% transmissivity to the laser pulse (which is at 1.06 microns, Kiyama, column 8, lines 49-67).
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Kiyama, et al. (U.S. Patent ) in view of Moslehi, et al. (U.S. Patent Application Publication 2012/0305063 A1), and further in view of Nakai, et al. (U.S. Patent Application Publication 2020/0098939 A1).
In reference to Claim 15, Kiyama is silent regarding the width of the laser pulse of the method of his invention.
Therefore, he does not teach that the laser pulse has a pulse width of less than 5,000 ps.
To solve the same problem of processing a solar cell with a YAG laser, Nakai teaches that such lasers may suitably have a pulse width of 2 nsec (i.e. 2000 ps) (paragraph [0055]).
Therefore, absent a showing of persuasive secondary considerations, it would have been obvious to one of ordinary skill in the art at the time the instant invention was filed to have formed the pulse width of the laser pulse of the method of modified Kiyama to have a width of 2 ns/2000 ps, because Nakai teaches that this is a suitable pulse width for a YAG laser used to pattern a solar cell (paragraph [0055]).
Forming the pulse width of the YAG laser of modified Kiyama to have a pulse width of 2 ns/2000 ps teaches the limitations of Claim 15, wherein the laser pulse has a pulse width of less than 5,000 ps.
Response to Arguments
Applicant’s arguments with respect to the claims have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
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/SADIE WHITE/Primary Examiner, Art Unit 1721
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