DETAILED ACTION
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 .
Status of Claims
Claims 1, 3, and 6-21 as amended and new claim 24 are presently under consideration as set forth in applicant’s response dated 09 January 2026. Claims 2, 4-5, and 22-23 are cancelled by applicant’s amendments.
Applicant’s amendments to the claims have overcome the prior art anticipation grounds of rejection of Lee et al as evidenced by Sugiura et al which is now withdrawn.
Applicant’s amendments to the claims have overcome the prior indefiniteness grounds of rejection under 35 U.S.C. 112(b) which are now withdrawn.
Upon further search and consideration of applicant’s newly amended and presented claims, the prior obviousness grounds of rejection under Lin et al (US 2018/0114871) is updated to show where the new claim limitations are taught disclosed or made obvious over the prior art of record and is otherwise maintained.
Applicant’s amendments to the claims have raised new issues of indefiniteness under 35 U.S.C. 112(b) which are detailed below.
Applicant’s arguments and remarks where applicable are addressed below.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1, 3, 6-17, and 24 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites “a material of the front contact selective layer” but no front contact selective layer was previously defined and thus this recitation lacks antecedent basis in claim 1 as it’s not clear if the recited front contact selective layer means to refer to the front selective contact layer or a different layer. As such, the scope of claim 1 cannot be determined and is rendered indefinite.
Claims 3, 6-17, and 24 are also rendered indefinite by depending from indefinite claim 1.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 3, 7-8, 16-21 and 24 are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al (US 2018/0114871), and further in view of Acharyya et al (Performance analysis of different dielectrics for solar cells with TOPCon structure, Journal of Computational Electronics, February 2022, 21(2):471-490) as evidenced by Sugiura et al (Numerical analysis of tunnel oxide passivated contact solar cell performances for dielectric thin film materials and bulk properties, Solar Energy 214 (2021) 205–213) and further in view of Lien et al ("Surface Passivation Materials for High-Efficiency Silicon Solar Cells." Materials for Energy (2020): 413-441.).
Regarding claims 1 and 3 Lin discloses a solar cell, comprising:
a silicon substrate ([0035], Fig. 3 see: silicon substrate 100); and
a majority carrier tunneling field effect layer (302) and a front selective contact layer (306, 318 forming a multi-layer front selective contact) that are stacked in sequence on a light receiving side of the silicon substrate ([0035], Fig. 3 see: passivation layer 302 with doped polysilicon layer 306 and transparent conductive layer 318 stacked on a top surface (considered to be light receiving surface) of the silicon substrate 100);
wherein the front selective contact layer and the silicon substrate are of a same doping type ([0035], Fig. 3 see: the silicon substrate 100, the doped polysilicon layer 306, and the doped region 308 are of the first conductivity type), and wherein the front selective contact layer immediately overlays on the majority carrier tunneling field effect layer (Fig. 3 see: multi-layer front selective contact formed by doped polysilicon layer 306 and transparent conductive layer 318 immediately overlies the passivation layer 302)
wherein the majority carrier tunneling field effect layer comprises pinholes filled with a material of the front contact selective layer (Lin, [0037] Fig. 3 see: plurality of holes 310 penetrates the passivation layer 302 and are filled by transparent conductive layer 318 a material of the front selective contact).
Although Lin discloses wherein the majority carrier tunneling field effect layer comprises a dielectric material ([0013], [0037] see for instance silicon oxide) Lin does not explicitly disclose an embodiment wherein a density of fixed charges in the majority carrier tunneling field effect layer is greater than or equal to 1010/cm3, and a type of the fixed charges in the majority carrier tunneling field effect layer is the same as a charge type of minority carriers in the silicon substrate.
Acharyya teaches TOPCon solar cells employing different dielectric materials including Al2O3 and HfO2 as the tunneling passivation layer compared to silicon oxide (Acharyya, see Abstract) where Acharyya teaches p-type TOPCon structures with an Al2O3 tunneling layer has excellent performance (Page 477 right hand column and Tables 3-6) while n-type TOPCon structures with an HfO2 tunneling layer shows excellent performance (Page 477 right hand column and Tables 8-11) and Al2O3 and HfO2 as the tunneling passivation layer maintaining efficiency performance at greater thicknesses compared to silicon oxide (see Tables 16 and 21) allowing for relaxed thickness requirements.
Acharyya and Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Acharyya such that the majority carrier tunneling field effect layer comprises a dielectric material of Al2O3 when the first conductivity type of the silicon substrate 100 and the doped region 308 are p-type as in Acharyya or comprises a dielectric material of HfO2 when the first conductivity type of the silicon substrate 100 and the doped region 308 are n-type as in Acharyya as Acharyya teaches p-type TOPCon structures with an Al2O3 tunneling layer has excellent performance (Page 477 right hand column and Tables 3-6 of Acharyya) while n-type TOPCon structures with an HfO2 tunneling layer shows excellent performance (Page 477 right hand column and Tables 8-11 of Acharyya) compared to silicon oxide and Al2O3 and HfO2 as the tunneling passivation layer maintaining efficiency performance at greater thicknesses compared to silicon oxide (see Tables 16 and 21 of Acharyya) allowing for relaxed thickness requirements.
Furthermore Sugiura teaches the relative permittivity (dielectric constant) of Al2O3 and HfO2 are 9.1 and 22 respectively (See Table 1 on page 206).
As such, by the modification of Acharyya, the dielectric material of modified Lin (Al2O3 or HfO2) has a type of the fixed charges in the majority carrier tunneling field effect layer is the same as a charge type of minority carriers in the silicon substrate (Al2O3 has negative fixed charges, same charge as electron minority carriers in p-type silicon, and HfO2 has positive fixed charges, same charge as hole minority carriers in n-type silicon).
Regarding the claim 1 limitation “wherein a density of fixed charges in the majority carrier tunneling field effect layer is greater than or equal to 1010/cm3“ and the claim 3 limitation “wherein the density of fixed charges in the majority carrier tunneling field effect layer is greater than or equal to 1011/cm3” Acharyya teaches fixed charges for the dielectric/Si interface of Al2O3 and HfO2 as −1× -1013 cm-2 and +2× -1012 cm-2 respectively (see Table 2 on page 475 and Fig. 11 on page 489).
In the alternative where it’s not clear that modified Lin discloses wherein the preset density is greater than or equal to 1010/cm2 and wherein the preset density is greater than or equal to 1011/cm2, Lien teaches Al2O3 dielectric passivation films typically have a fixed charge density at the level of 1012 cm−2 (Lien, Pages 422-423, section 11.2.2 Aluminum Oxide Thin Films, see Table 11.3).
Lien and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Lien such that the fixed charge density of the majority carrier tunneling field effect layer is greater than or equal to 1010/cm2 or 1011/cm2 as in Lien (Lien, Pages 422-423, section 11.2.2 Aluminum Oxide Thin Films, see Table 11.3 see: Al2O3 dielectric passivation films typically have a fixed charge density at the level of 1012 cm−2) as such a modification would have amounted to the selection of a known fixed charge density for its intended use in the known environment of a solar cell to accomplish an entirely expected result of providing passivation and charge selective transport.
Regarding claim 7 modified Lin discloses the solar cell according to claim 1, and Acharyya further teaches wherein the majority carrier tunneling layer comprises a dielectric material, wherein the dielectric material comprises a transition metal oxide (Acharyya, Abstract see: HfO2).
Regarding claim 8 modified Lin discloses the solar cell according to claim 7, wherein the silicon substrate is an N-type silicon substrate ([0035], [0017] Fig. 3 see: the silicon substrate 100 is of the first conductivity type which can be n-type), and Acharyya further teaches wherein the dielectric material comprises at least one of hafnium oxide, hafnium silicon oxide, yttrium oxide, or a lanthanide metal oxide (Acharyya, Abstract see: HfO2).
Regarding claim 16 modified Lin discloses the solar cell according to claim 1, wherein:
the front selective contact layer is a multi-layer structure (Lin, [0035] Fig. 3 see: doped polysilicon layer 306 and transparent conductive layer 318);
the solar cell is one of a heterojunction solar cell, a polysilicon passivated contact solar cell, or a wide-bandgap passivated contact solar cell ([0035], Fig. 3 see: solar cell 30 is a polysilicon passivated contact solar cell); and
the silicon substrate comprises a front junction structure or a back junction structure ([0035], Fig. 3 see: doped region 308 or doped region 108 in silicon substrate 100).
Regarding claim 17 modified Lin discloses the solar cell according to claim 16, wherein the front selective contact layer comprises at least one of doped amorphous silicon, doped polysilicon, aluminum-doped zinc oxide, indium tin oxide, zinc oxide, tin oxide, nickel oxide, titanium nitride, or molybdenum oxide ([0035], [0118] Fig. 3 see: doped polysilicon layer 306 and transparent conductive layer 318 such as indium tin oxide).
Regarding claim 18 Lin discloses a photovoltaic assembly, comprising one or more solar cells, wherein a solar cell comprises:
a silicon substrate ([0035], Fig. 3 see: silicon substrate 100); and
a majority carrier tunneling field effect layer (302) and a front selective contact layer (306, 318 forming a multi-layer front selective contact) that are stacked in sequence on a light receiving side of the silicon substrate ([0035], Fig. 3 see: passivation layer 302 with doped polysilicon layer 306 and transparent conductive layer 318 stacked on a top surface (considered to be light receiving surface) of the silicon substrate 100);
wherein the front selective contact layer and the silicon substrate are of a same doping type ([0035], Fig. 3 see: the silicon substrate 100, the doped polysilicon layer 306, and the doped region 308 are of the first conductivity type), and wherein the front selective contact layer immediately overlays on the majority carrier tunneling field effect layer (Fig. 3 see: multi-layer front selective contact formed by doped polysilicon layer 306 and transparent conductive layer 318 immediately overlies the passivation layer 302)
wherein the majority carrier tunneling field effect layer comprises pinholes filled with a material of the front contact selective layer (Lin, [0037] Fig. 3 see: plurality of holes 310 penetrates the passivation layer 302 and are filled by transparent conductive layer 318 a material of the front selective contact).
Although Lin discloses wherein the majority carrier tunneling field effect layer comprises a dielectric material ([0013], [0037] see for instance silicon oxide) Lin does not explicitly disclose an embodiment wherein a density of fixed charges in the majority carrier tunneling field effect layer is greater than or equal to 1010/cm3, and a type of the fixed charges in the majority carrier tunneling field effect layer is the same as a charge type of minority carriers in the silicon substrate.
Acharyya teaches TOPCon solar cells employing different dielectric materials including Al2O3 and HfO2 as the tunneling passivation layer compared to silicon oxide (Acharyya, see Abstract) where Acharyya teaches p-type TOPCon structures with an Al2O3 tunneling layer has excellent performance (Page 477 right hand column and Tables 3-6) while n-type TOPCon structures with an HfO2 tunneling layer shows excellent performance (Page 477 right hand column and Tables 8-11) and Al2O3 and HfO2 as the tunneling passivation layer maintaining efficiency performance at greater thicknesses compared to silicon oxide (see Tables 16 and 21) allowing for relaxed thickness requirements.
Acharyya and Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Acharyya such that the majority carrier tunneling field effect layer comprises a dielectric material of Al2O3 when the first conductivity type of the silicon substrate 100 and the doped region 308 are p-type as in Acharyya or comprises a dielectric material of HfO2 when the first conductivity type of the silicon substrate 100 and the doped region 308 are n-type as in Acharyya as Acharyya teaches p-type TOPCon structures with an Al2O3 tunneling layer has excellent performance (Page 477 right hand column and Tables 3-6 of Acharyya) while n-type TOPCon structures with an HfO2 tunneling layer shows excellent performance (Page 477 right hand column and Tables 8-11 of Acharyya) compared to silicon oxide and Al2O3 and HfO2 as the tunneling passivation layer maintaining efficiency performance at greater thicknesses compared to silicon oxide (see Tables 16 and 21 of Acharyya) allowing for relaxed thickness requirements.
Furthermore Sugiura teaches the relative permittivity (dielectric constant) of Al2O3 and HfO2 are 9.1 and 22 respectively (See Table 1 on page 206).
As such, by the modification of Acharyya, the dielectric material of modified Lin (Al2O3 or HfO2) has a type of the fixed charges in the majority carrier tunneling field effect layer is the same as a charge type of minority carriers in the silicon substrate (Al2O3 has negative fixed charges, same charge as electron minority carriers in p-type silicon, and HfO2 has positive fixed charges, same charge as hole minority carriers in n-type silicon).
Regarding the claim 18 limitation “wherein a density of fixed charges in the majority carrier tunneling field effect layer is greater than or equal to 1010/cm3“ Acharyya teaches fixed charges for the dielectric/Si interface of Al2O3 and HfO2 as −1× -1013 cm-2 and +2× -1012 cm-2 respectively (see Table 2 on page 475 and Fig. 11 on page 489).
In the alternative where it’s not clear that modified Lin discloses wherein the preset density is greater than or equal to 1010/cm2, Lien teaches Al2O3 dielectric passivation films typically have a fixed charge density at the level of 1012 cm−2 (Lien, Pages 422-423, section 11.2.2 Aluminum Oxide Thin Films, see Table 11.3).
Lien and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Lien such that the fixed charge density of the majority carrier tunneling field effect layer is greater than or equal to 1010/cm2 as in Lien (Lien, Pages 422-423, section 11.2.2 Aluminum Oxide Thin Films, see Table 11.3 see: Al2O3 dielectric passivation films typically have a fixed charge density at the level of 1012 cm−2) as such a modification would have amounted to the selection of a known fixed charge density for its intended use in the known environment of a solar cell to accomplish an entirely expected result of providing passivation and charge selective transport.
Regarding claim 19 Lin discloses a method for forming a solar cell, comprising:
forming a majority carrier tunneling field effect layer (302) and a front selective contact layer (306, 318 forming a multi-layer front selective contact) that are stacked in sequence on a light receiving side of a silicon substrate ([0035], Fig. 3 see: passivation layer 302 with doped polysilicon layer 306 and transparent conductive layer 318 stacked on a top surface (considered to be light receiving surface) of the silicon substrate 100);
wherein the front selective contact layer and the silicon substrate are of a same doping type ([0035], Fig. 3 see: the silicon substrate 100, the doped polysilicon layer 306, and the doped region 308 are of the first conductivity type), and wherein the front selective contact layer immediately overlays on the majority carrier tunneling field effect layer (Fig. 3 see: multi-layer front selective contact formed by doped polysilicon layer 306 and transparent conductive layer 318 immediately overlies the passivation layer 302)
wherein the majority carrier tunneling field effect layer comprises pinholes filled with a material of the front contact selective layer (Lin, [0037] Fig. 3 see: plurality of holes 310 penetrates the passivation layer 302 and are filled by transparent conductive layer 318 a material of the front selective contact).
Although Lin discloses wherein the majority carrier tunneling field effect layer comprises a dielectric material ([0013], [0037] see for instance silicon oxide) Lin does not explicitly disclose an embodiment wherein a density of fixed charges in the majority carrier tunneling field effect layer is greater than or equal to 1010/cm3, and a type of the fixed charges in the majority carrier tunneling field effect layer is the same as a charge type of minority carriers in the silicon substrate.
Acharyya teaches TOPCon solar cells employing different dielectric materials including Al2O3 and HfO2 as the tunneling passivation layer compared to silicon oxide (Acharyya, see Abstract) where Acharyya teaches p-type TOPCon structures with an Al2O3 tunneling layer has excellent performance (Page 477 right hand column and Tables 3-6) while n-type TOPCon structures with an HfO2 tunneling layer shows excellent performance (Page 477 right hand column and Tables 8-11) and Al2O3 and HfO2 as the tunneling passivation layer maintaining efficiency performance at greater thicknesses compared to silicon oxide (see Tables 16 and 21) allowing for relaxed thickness requirements.
Acharyya and Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Acharyya such that the majority carrier tunneling field effect layer comprises a dielectric material of Al2O3 when the first conductivity type of the silicon substrate 100 and the doped region 308 are p-type as in Acharyya or comprises a dielectric material of HfO2 when the first conductivity type of the silicon substrate 100 and the doped region 308 are n-type as in Acharyya as Acharyya teaches p-type TOPCon structures with an Al2O3 tunneling layer has excellent performance (Page 477 right hand column and Tables 3-6 of Acharyya) while n-type TOPCon structures with an HfO2 tunneling layer shows excellent performance (Page 477 right hand column and Tables 8-11 of Acharyya) compared to silicon oxide and Al2O3 and HfO2 as the tunneling passivation layer maintaining efficiency performance at greater thicknesses compared to silicon oxide (see Tables 16 and 21 of Acharyya) allowing for relaxed thickness requirements.
Furthermore Sugiura teaches the relative permittivity (dielectric constant) of Al2O3 and HfO2 are 9.1 and 22 respectively (See Table 1 on page 206).
As such, by the modification of Acharyya, the dielectric material of modified Lin (Al2O3 or HfO2) has a type of the fixed charges in the majority carrier tunneling field effect layer is the same as a charge type of minority carriers in the silicon substrate (Al2O3 has negative fixed charges, same charge as electron minority carriers in p-type silicon, and HfO2 has positive fixed charges, same charge as hole minority carriers in n-type silicon).
Regarding the claim 19 limitation “wherein a density of fixed charges in the majority carrier tunneling field effect layer is greater than or equal to 1010/cm3“ Acharyya teaches fixed charges for the dielectric/Si interface of Al2O3 and HfO2 as −1× -1013 cm-2 and +2× -1012 cm-2 respectively (see Table 2 on page 475 and Fig. 11 on page 489).
In the alternative where it’s not clear that modified Lin discloses wherein the preset density is greater than or equal to 1010/cm2, Lien teaches Al2O3 dielectric passivation films typically have a fixed charge density at the level of 1012 cm−2 (Lien, Pages 422-423, section 11.2.2 Aluminum Oxide Thin Films, see Table 11.3).
Lien and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Lien such that the fixed charge density of the majority carrier tunneling field effect layer is greater than or equal to 1010/cm2 as in Lien (Lien, Pages 422-423, section 11.2.2 Aluminum Oxide Thin Films, see Table 11.3 see: Al2O3 dielectric passivation films typically have a fixed charge density at the level of 1012 cm−2) as such a modification would have amounted to the selection of a known fixed charge density for its intended use in the known environment of a solar cell to accomplish an entirely expected result of providing passivation and charge selective transport.
Regarding claim 20 modified Lin discloses the method according to claim 19, but does not explicitly disclose wherein the method further comprises: performing charge injection on the majority carrier tunneling field effect layer, to cause a charge type on a surface of the majority carrier tunneling field effect layer that is proximate to the silicon substrate to be the same as a charge type of the fixed charges.
However, Lien further teaches for Aluminum oxide passivation layers and hafnium oxide passivation layers a post deposition annealing process is performed to activate the passivation of the crystalline silicon substrate, and in the case of aluminum oxide increases the density of negative charges at the Al2O3/c-Si interface and improve field-effect passivation (Lien, see Section “11.3.2 EFFECT OF POST-ANNEALING AMBIENT TEMPERATURE” on Pages 426-430 and see Table 11.5 on Page 429).
Lien and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Lien such that the method of Lin further comprises performing charge injection on the majority carrier tunneling field effect layer, to cause a charge type on a surface of the majority carrier tunneling field effect layer that is proximate to the silicon substrate to be the same as a charge type of the fixed charges as in Lien (see Section “11.3.2 EFFECT OF POST-ANNEALING AMBIENT TEMPERATURE” on Pages 426-430 and see Table 11.5 on Page 429 see: for Aluminum oxide passivation layers and hafnium oxide passivation layers a post deposition annealing process is performed to activate the passivation of the crystalline silicon substrate, and in the case of aluminum oxide increases the density of negative charges at the Al2O3/c-Si interface and improve field-effect passivation) for the purpose of improving field-effect passivation as taught by Lien above.
Regarding claim 21 modified Lin discloses the method according to claim 20, and Lien further teaches wherein the charge injection comprises at least one of electrical injection, optical injection, or hot injection (Lien, see Section “11.3.2 EFFECT OF POST-ANNEALING AMBIENT TEMPERATURE” on Pages 426-430 and see Table 11.5 on Page 429 see: post deposition annealing process meet the limitation of a “hot injection”).
Regarding claim 24 modified Lin discloses the solar cell of claim 1, and wherein the Sugiura teaches the relative permittivity (dielectric constant) of Al2O3 and HfO2 are 9.1 and 22 respectively (See Table 1 on page 206) and thus the majority carrier tunneling field effect layer comprises a dielectric material with a dielectric constant greater than or equal to 8.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Lin et al (US 2018/0114871), in view of Acharyya et al (Performance analysis of different dielectrics for solar cells with TOPCon structure, Journal of Computational Electronics, February 2022, 21(2):471-490) as evidenced by Sugiura et al (Numerical analysis of tunnel oxide passivated contact solar cell performances for dielectric thin film materials and bulk properties, Solar Energy 214 (2021) 205–213) in view of Lien et al ("Surface Passivation Materials for High-Efficiency Silicon Solar Cells." Materials for Energy (2020): 413-441.) as applied to claims 1, 3, 7-8, 16-21 and 24 above, and further in view of Zhang et al (Carrier transport through the ultrathin silicon-oxide layer in tunnel oxide passivated contact (TOPCon) c-Si solar cells, Solar Energy Materials and Solar Cells 187 (2018) 113–122) or alternatively in view of Tetzlaff et al (Evolution Of Oxide Disruptions: The (W)hole Story About poly-Si / c-Si Passivating Contacts, 2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC), Portland, OR, USA, 2016, pp. 0221-0224).
Regarding claim 6 modified Lin discloses the solar cell according to claim 1, but does not explicitly disclose where an average diameter of the pinholes is less than or equal to 100 nm, and a density of the pinholes is less than or equal to 109/cm2.
However, Zhang teaches for TOPCon solar cells optimized pinhole density and size distribution is critical engineering for solar cell performance optimization as tunneling does not provide a sufficient high transport channel for carrier transport, and the introduction of a small number of transports through pinholes improves the fill factor (FF) and reduces the series resistance (Rs), hence improves the photovoltaic conversion efficiency (PCE). However, a high possibility for carrier going through pinholes reduces all of the performance parameters and degrades PCE for all the cases simulated (Zhang, see Abstract).
As such, the fill factor (FF) series resistance (Rs) and photovoltaic conversion efficiency (PCE) are variables that can be modified by varying the average diameter of the pinholes and density of the pinholes in the solar cell of modified Lin as evidenced by Zhang above. For that reason, the average diameter of the pinholes and density of the pinholes, would have been considered a result effective variable by one having ordinary skill in the art at the time the invention was made. As such, without showing unexpected results, the average diameter of the pinholes and density of the pinholes cannot be considered critical. Accordingly, one of ordinary skill in the art at the time the invention was made would have optimized, by routine experimentation, the average diameter of the pinholes and density of the pinholes in the solar cell of modified Lin to obtain the desired fill factor (FF) series resistance (Rs) and photovoltaic conversion efficiency (PCE) (In re Boesch, 617 F.2d. 272, 205 USPQ 215 (CCPA 1980)), since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223).
Alternatively, Tetzlaff teaches a TOPCon solar cell where an average diameter of the pinholes is less than or equal to 100 nm (Tetzlaff, right hand column of page 0221 and right hand column of page 0222 see: pin hole diameter around 5 nm and increases to 18nm and 32nm in diameter with annealing temperature), and a density of the pinholes is less than or equal to 109/cm2 (Tetzlaff, right hand column of page 0223 see: estimated pinhole density in the range of 108 cm-2) and teaches higher hole densities and higher hole widths lead to worse electrical results such as higher emitter saturation current density J0e (Tetzlaff, see paragraph under “III. Results and Discussions” on page 0222, and see right hand column of page 0223).
Tetzlaff and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Tetzlaff such that the average diameter of the pinholes is less than or equal to 100 nm as in Tetzlaff (Tetzlaff, right hand column of page 0221 and right hand column of page 0222 see: pin hole diameter around 5 nm and increases to 18nm and 32nm in diameter with annealing temperature), and a density of the pinholes is less than or equal to 109/cm2 as in Tetzlaff (Tetzlaff, right hand column of page 0223 see: estimated pinhole density in the range of 108 cm-2) as Tetzlaff teaches higher hole densities and higher hole widths (diameters) lead to worse electrical results such as higher emitter saturation current density J0e (Tetzlaff, see paragraph under “III. Results and Discussions” on page 0222, and see right hand column of page 0223).
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Lin et al (US 2018/0114871), in view of Acharyya et al (Performance analysis of different dielectrics for solar cells with TOPCon structure, Journal of Computational Electronics, February 2022, 21(2):471-490) as evidenced by Sugiura et al (Numerical analysis of tunnel oxide passivated contact solar cell performances for dielectric thin film materials and bulk properties, Solar Energy 214 (2021) 205–213) in view of Lien et al ("Surface Passivation Materials for High-Efficiency Silicon Solar Cells." Materials for Energy (2020): 413-441.) as applied to claims 1, 3, 7-8, 16-21 and 24 above, and further in view of Yoshikawa et al (US 2018/0190839).
Regarding claim 9 modified Lin discloses the solar cell according to claim 1, but does not explicitly disclose wherein a material of the majority carrier tunneling field effect layer comprises hydrogen.
Yoshikawa teaches passivation layers for solar cells can further be formed from aluminum oxide or hydrogenated aluminum oxide (Yoshikawa, [0063], Fig. 2 see: first passivation layer 14 formed of aluminum oxide (AlOx1) or hydrogenated aluminum oxide (AlOx1:H)).
Yoshikawa and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Yoshikawa such that the aluminum oxide passivation layer of Lin is a hydrogenated aluminum oxide as in Yoshikawa (Yoshikawa, [0063], Fig. 2 see: first passivation layer 14 formed of aluminum oxide (AlOx1) or hydrogenated aluminum oxide (AlOx1:H)) for the purpose of providing improved passivation at the surface of the silicon substrate of Lin.
Claims 10-11 are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al (US 2018/0114871), in view of Acharyya et al (Performance analysis of different dielectrics for solar cells with TOPCon structure, Journal of Computational Electronics, February 2022, 21(2):471-490) as evidenced by Sugiura et al (Numerical analysis of tunnel oxide passivated contact solar cell performances for dielectric thin film materials and bulk properties, Solar Energy 214 (2021) 205–213) in view of Lien et al ("Surface Passivation Materials for High-Efficiency Silicon Solar Cells." Materials for Energy (2020): 413-441.) as applied to claims 1, 3, 7-8, 16-21 and 24 above, and further in view of CHEONG et al (US 2015/0179837).
Regarding claim 10 modified Lin discloses the solar cell according to claim 1, but does not explicitly disclose wherein the solar cell further comprises a chemical passivation interface layer between the silicon substrate and the majority carrier tunneling field effect layer, wherein a thickness of the chemical passivation interface layer is less than or equal to 1 nm, wherein the thickness is measured along a direction perpendicular to a light receiving surface of the silicon substrate.
CHEONG discloses a solar cell with an aluminum oxide passivation layer and further comprising a silicon oxide chemical passivation interface layer with a thickness of about 1 nm to 3 nm formed at an interface of the aluminum oxide layer and semiconductor substrate (CHEONG, [0125]-[0127] Fig. 2 see: forming SiOx layers 131 and 161 at interfaces between AlOX layers 133 and 163 and substrate 110). CHEONG discloses this layer minimizes the interface trap density by a chemical passivation effect and may serve as a tunneling oxide layer (CHEONG, [0127]).
CHEONG and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of CHEONG such that the device of Lin further comprises a chemical passivation interface layer between the silicon substrate of Lin and the aluminum oxide passivation layer of Lin (the majority carrier tunneling field effect layer) as in CHEONG (CHEONG, [0125]-[0127] Fig. 2 see: forming SiOx layers 131 and 161 at interfaces between AlOX layers 133 and 163 and substrate 110) as CHEONG discloses this layer minimizes the interface trap density by a chemical passivation effect and may serve as a tunneling oxide layer (CHEONG, [0127]).
Furthermore regarding the recitation “wherein a thickness of the chemical passivation interface layer is less than or equal to 1 nm, wherein the thickness is measured along a direction perpendicular to a light receiving surface of the silicon substrate” CHEONG discloses an overlapping thickness range of about 1 nm to 3 nm (para [0125]). It is well settled that where the prior art describes the components of a claimed compound or compositions in concentrations within or overlapping the claimed concentrations a prima facie case of obviousness is established. See In re Harris, 409 F.3d 1339, 1343, 74 USPQ2d 1951, 1953 (Fed. Cir 2005); In re Peterson, 315 F.3d 1325, 1329, 65 USPQ 2d 1379, 1382 (Fed. Cir. 1997); In re Woodruff, 919 F.2d 1575, 1578 16 USPQ2d 1934, 1936-37 (CCPA 1990); In re Malagari, 499 F.2d 1297, 1303, 182 USPQ 549, 553 (CCPA 1974).
Regarding claim 11 modified Lin discloses the solar cell according to claim 10, wherein the chemical passivation interface layer is located on a surface of the silicon substrate (CHEONG, [0125]-[0127] Fig. 2 see: forming SiOx layers 131 and 161 at interfaces between AlOX layers 133 and 163 and substrate 110), the chemical passivation interface layer is a silicon-oxygen bond layer (CHEONG, [0125]-[0127] Fig. 2 see: SiOx layers 131 and 161 are a silicon-oxygen bond layer), and regarding claim 11 limitation “the thickness of the chemical passivation interface layer is less than or equal to 0.5 nm”, CHEONG discloses the chemical passivation interface layer thickness range of about 1 nm to 3 nm (para [0125]) which is close to applicant’s claimed range. Similarly, a prima facie case of obviousness exists where the claimed ranges and prior art ranges do not overlap but are close enough that one skilled in the art would have expected them to have the same properties. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 227 USPQ 773 (Fed. Cir. 1985) (Court held as proper a rejection of a claim directed to an alloy of “having 0.8% nickel, 0.3% molybdenum, up to 0.1% iron, balance titanium” as obvious over a reference disclosing alloys of 0.75% nickel, 0.25% molybdenum, balance titanium and 0.94% nickel, 0.31% molybdenum, balance titanium.).
Alternatively, as the thickness of this silicon oxide chemical passivation interface layer contributes to the total thickness of the majority carrier tunneling field effect layer, which contributes to solar cell efficiency as taught by Acharyya (see Tables 16 and 21), the solar cell efficiency is a variable that can be modified by varying the thickness of the chemical passivation interface layer in the solar cell of modified Lin as evidenced by Acharyya above. For that reason, the thickness of the chemical passivation interface layer, would have been considered a result effective variable by one having ordinary skill in the art at the time the invention was made. As such, without showing unexpected results, t the thickness of the chemical passivation interface layer cannot be considered critical. Accordingly, one of ordinary skill in the art at the time the invention was made would have optimized, by routine experimentation, the thickness of the chemical passivation interface layer in the solar cell of modified Lin to obtain the desired solar cell efficiency (In re Boesch, 617 F.2d. 272, 205 USPQ 215 (CCPA 1980)), since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223).
Claims 12-13 are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al (US 2018/0114871), in view of Acharyya et al (Performance analysis of different dielectrics for solar cells with TOPCon structure, Journal of Computational Electronics, February 2022, 21(2):471-490) as evidenced by Sugiura et al (Numerical analysis of tunnel oxide passivated contact solar cell performances for dielectric thin film materials and bulk properties, Solar Energy 214 (2021) 205–213) in view of Lien et al ("Surface Passivation Materials for High-Efficiency Silicon Solar Cells." Materials for Energy (2020): 413-441.) as applied to claims 1, 3, 7-8, 16-21 and 24 above, and further in view of Li et al (CN 111816726A, reference made to attached English machine translation).
Regarding claim 12 modified Lin discloses the solar cell according to claim 1, wherein a thickness of the majority carrier tunneling field effect layer is in a range of 0.5 to 5 nm, and the thickness is measured along a direction perpendicular to a light receiving surface of the silicon substrate Acharyya (see Tables 16 and 21 where thicknesses of the tunnel layer are between 0.5 and 5 nm) but does not explicitly disclose wherein the majority carrier tunneling field effect layer is a multi-layer structure.
Li discloses a solar cell where majority carrier tunneling field effect layers can be formed as single layers or multi-layer structures (Li, see top of page 3 and bottom of page 6 of translation, see: tunneling isolation layer has one layer or multiple layers with a thickness of 0.1 to 5 nm).
Li and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Li such that the majority carrier tunneling field effect layer of Lin is a multi-layer structure as taught by Li (Li, see top of page 3 and bottom of page 6 of translation, see: tunneling isolation layer has one layer or multiple layers with a thickness of 0.1 to 5 nm) as such a modification would have amounted to the selection of known tunnel oxide materials and structure for their intended use in the known environment of a solar cell to accomplish the entirely expected results of providing good surface chemical and field passivation effect.
Regarding claim 13 modified Lin discloses the solar cell according to claim 12, and regarding the claim 13 limitation “wherein the thickness of the majority carrier tunneling field effect layer is in a range of 0.5 to 2 nm” Li teaches a range of a thickness of 0.1 to 5 nm of the majority carrier tunneling field effect layer (Li, see top of page 3 and bottom of page 6 of translation) that entirely encompasses the claimed range. It is well settled that where the prior art describes the components of a claimed compound or compositions in concentrations within or overlapping the claimed concentrations a prima facie case of obviousness is established. See In re Harris, 409 F.3d 1339, 1343, 74 USPQ2d 1951, 1953 (Fed. Cir 2005); In re Peterson, 315 F.3d 1325, 1329, 65 USPQ 2d 1379, 1382 (Fed. Cir. 1997); In re Woodruff, 919 F.2d 1575, 1578 16 USPQ2d 1934, 1936-37 (CCPA 1990); In re Malagari, 499 F.2d 1297, 1303, 182 USPQ 549, 553 (CCPA 1974).
Claims 14-15 are rejected under 35 U.S.C. 103 as being unpatentable over Lin et al (US 2018/0114871), in view of Acharyya et al (Performance analysis of different dielectrics for solar cells with TOPCon structure, Journal of Computational Electronics, February 2022, 21(2):471-490) as evidenced by Sugiura et al (Numerical analysis of tunnel oxide passivated contact solar cell performances for dielectric thin film materials and bulk properties, Solar Energy 214 (2021) 205–213) in view of Lien et al ("Surface Passivation Materials for High-Efficiency Silicon Solar Cells." Materials for Energy (2020): 413-441.) as applied to claims 1, 3, 7-8, 16-21 and 24 above, and further in view of Lee et al (KR 101867969B1, reference made to attached English machine translation).
Regarding claim 14 modified Lin discloses the solar cell according to claim 1, but does not explicitly disclose wherein an area of a projection of the front selective contact layer on a light receiving surface of the silicon substrate is less than or equal to an area of the light receiving surface; and wherein an area of a projection of the majority carrier tunneling field effect layer on the light receiving surface is less than or equal to the area of the light receiving surface.
Lee discloses a solar cell wherein an area of a projection of the front selective contact layer on a light receiving surface of the silicon substrate is less than or equal to an area of the light receiving surface (Fig. 1 see: one projection/protrusion 112 of the front emitter section 140 is less than the total area of the light receiving surface of semiconductor substrate 110); and wherein an area of a projection of the majority carrier tunneling field effect layer on the light receiving surface is less than or equal to the area of the light receiving surface (Fig. 1 see: one projection/protrusion 112 of the front passivation film 120 is less than the total area of the light receiving surface of semiconductor substrate 110). Lee teaches these protrusions function to reduce reflection at the surface of the solar cell and reduce optical loss in the solar cell (Lee, see middle of page 3 of translation).
Lee and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Lee to further comprise a plurality of protrusions at the front surface such that an area of a projection of the front selective contact layer on a light receiving surface of the silicon substrate is less than or equal to an area of the light receiving surface as in Lee (Fig. 1 see: one projection/protrusion 112 of the front emitter section 140 is less than the total area of the light receiving surface of semiconductor substrate 110); and wherein an area of a projection of the majority carrier tunneling field effect layer on the light receiving surface is less than or equal to the area of the light receiving surface as in Lee (Fig. 1 see: one projection/protrusion 112 of the front passivation film 120 is less than the total area of the light receiving surface of semiconductor substrate 110) as Lee teaches these protrusions function to reduce reflection at the surface of the solar cell and reduce optical loss in the solar cell (Lee, see middle of page 3 of translation).
Regarding claim 15 modified Lin discloses the solar cell according to claim 1, but does not explicitly disclose wherein an area of a projection of the majority carrier tunneling field effect layer on a light receiving surface of the silicon substrate is greater than or equal to an area of a projection of the front selective contact layer on the light receiving surface, and wherein the projection of the front selective contact layer falls within the projection of the majority carrier tunneling field effect layer.
Lee discloses the solar cell wherein an area of a projection of the majority carrier tunneling field effect layer on a light receiving surface of the silicon substrate is greater than or equal to an area of a projection of the front selective contact layer on the light receiving surface (Fig. 1 see: one projection/protrusion 112 of the front passivation film 120 is equal to the same projection/protrusion 112 of the front emitter section 140), and wherein the projection of the front selective contact layer falls within the projection of the majority carrier tunneling field effect layer (Fig. 1 see: one projection/protrusion 112 of the front emitter section 140 is on/within one projection/protrusion 112 of the front passivation film 120). Lee teaches these protrusions function to reduce reflection at the surface of the solar cell to reduce optical loss in the solar cell (Lee, see middle of page 3 of translation).
Lee and modified Lin are combinable as they are both concerned with the field of solar cells.
It would have been obvious to one having ordinary skill in the art at the time of the invention to modify the solar cell of Lin in view of Lee to further comprise a plurality of protrusions at the front surface such that an area of a projection of the majority carrier tunneling field effect layer on a light receiving surface of the silicon substrate is greater than or equal to an area of a projection of the front selective contact layer on the light receiving surface as in Lee (Fig. 1 see: one projection/protrusion 112 of the front passivation film 120 is equal to the same projection/protrusion 112 of the front emitter section 140), and wherein the projection of the front selective contact layer falls within the projection of the majority carrier tunneling field effect layer as in Lee (Fig. 1 see: one projection/protrusion 112 of the front emitter section 140 is on/within one projection/protrusion 112 of the front passivation film 120) as Lee teaches these protrusions function to reduce reflection at the surface of the solar cell to reduce optical loss in the solar cell (Lee, see middle of page 3 of translation).
Response to Arguments
Applicant's arguments filed 09 January 2026 have been fully considered but they are not persuasive.
Applicant argues on pages 9-10 of the response that the prior art of record, in particular Lin does not disclose the claim 1 limitations “wherein the front selective contact layer immediately overlays on the majority carrier tunneling field effect layer” and “wherein the majority carrier tunneling field effect layer comprises pinholes filled with a material of the front contact selective layer”, however this is not found persuasive as applicant’s arguments are not commensurate in scope with the limitations of the claims.
The claimed “front selective contact layer” is open to being a multi-layered structure (see claim 16 where it is explicitly claimed as such). The doped polysilicon layer 306 and transparent conductive layer 318 in Fig. 3 of Lin are together considered such a multi-layered structure forming a front selective contact layer that immediately overlays on the majority carrier tunneling field effect layer (passivation layer 302) and the plurality of holes 310 in the passivation layer 302 are filled by transparent conductive layer 318 a material of this multi-layered front selective contact layer (para [0037] Fig. 3). As such, the prior art of Lin teaches these claimed features.
Applicant’s further arguments and remarks depend from the arguments rebutted above and thus are considered moot.
Conclusion
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 nonprovisional extension fee (37 CFR 1.17(a)) 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 mailing date of this final action.
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ANDREW J. GOLDEN
Primary Examiner
Art Unit 1726
/ANDREW J GOLDEN/ Primary Examiner, Art Unit 1726
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