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
1, 5-8, 10-16, 19-21, 25, 36, 41, 43, and 51-53 are presently under consideration as amended in applicant’s response dated 24 November 2025 and supplemental response dated 25 November 2025. Claims 51-52 remain withdrawn and claims 2-4, 9, 17-18, 22-24, 26-35, 37-40, 42, and 44-50 remain cancelled.
Upon further search and consideration of applicant’s newly amended claims new prior art was discovered and a new grounds of rejection is set forth below
Applicant’s amendments to the claims have overcome the prior indefiniteness rejections under 35 U.S.C. 112(b) and are thus withdrawn.
Applicant’s amendments to the claims have raised new issues of indefiniteness under 35 U.S.C. 112(b) set forth below.
Applicant’s substitute specification filed with the supplemental response dated 25 November 2025 have overcome the objections to the specification which are thus withdrawn.
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, 5-8, 10-16, 19-21, 25, 36, 41, 43, and 53 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 the broad limitation “a metal-chalcogen-compound layer, wherein the metal-chalcogen-compound layer is deposited within at least the first region of the silicon substrate”, but then further recites the narrower limitation “a region of the metal-chalcogen-compound layer that corresponds to the second region forms a second-charge-carrier transferring region” A broad range or limitation together with a narrow range or limitation that falls within the broad range or limitation (in the same claim) may be considered indefinite if the resulting claim does not clearly set forth the metes and bounds of the patent protection desired. See MPEP § 2173.05(c). Claim 1 is thus considered indefinite because there is a question or doubt as to whether the feature introduced by such narrower language is (a) merely exemplary of the remainder of the claim, and therefore not required, or (b) a required feature of the claims.
Claim 1 further recites “the metal-chalcogen-compound layer is deposited on the non-light receiving surface shared by the silicon substrate and the second-charge-carrier selectively-collecting layer” where it’s unclear what surface “the non-light receiving surface shared by the silicon substrate and the second-charge-carrier selectively-collecting layer” is referencing as the silicon substrate and the second-charge-carrier selectively-collecting layer where never explicitly claimed as sharing a non-light receiving surface. Thus claim 1 lacks antecedent basis for this recitation of “the non-light receiving surface”. It’s unclear if this surface is the non-light receiving surface of the silicon substrate or a different surface.
Furthermore, it’s unclear what is meant by “shared by the silicon substrate and the second-charge-carrier selectively-collecting layer” within this context. It’s unclear if claim 1 means to claim the metal-chalcogen-compound layer deposited at an interface between the silicon substrate and the second-charge-carrier selectively-collecting layer or a different configuration.
For these reasons, the scope of claim 1 cannot be reasonably determined and is rendered indefinite.
Claims 5-8, 10-16, 19-21, 25, 36, 41, 43, and 53 are also rendered indefinite by depending from indefinite claim 1.
Claim 8 recites “the non-light receiving surface within the second region” where it’s unclear which or what non-light receiving surface is being referenced by this recitation. It’s unclear if the non-light receiving surface is the surface “shared by the silicon substrate and the second-charge-carrier selectively-collecting layer” or the non-light receiving surface of the silicon substrate. For this reason, the scope of claim 8 cannot be reasonably determined and is rendered indefinite.
Claim 10 is also rendered indefinite by depending from indefinite claim 8.
Claim 11 recites “the metal chalcogen compounds” but claim 1 from which claim 11 depends lacks antecedent basis for metal chalcogen compounds and it’s unclear what compounds are being referenced in claim 11. For this reason, the scope of claim 11 cannot be reasonably determined and is rendered indefinite.
Claim 36 depends from claim 1 and recites “the blocking component” but lacks antecedent basis for this recitation in the claim as claim 36 and claim 1 do not previously define a blocking component and it’s unclear what blocking component is being referenced in claim 36. As such, the scope of claim 36 cannot be determined and is rendered indefinite.
Claim 41 depends from claim 1 and recites “the blocking component” but lacks antecedent basis for this recitation in the claim as claim 41 and claim 1 do not previously define a blocking component and it’s unclear what blocking component is being referenced in claim 41. As such, the scope of claim 41cannot be determined and is rendered indefinite.
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 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, 6-8, 10, 12-13, 16, 19-20, 25, 36, 41, 43, and 53 are rejected under 35 U.S.C. 103 as being unpatentable over Carlson (US 2018/0366597), and further in view of Choi et al (KR 20150029202A, reference made to attached English machine translation).
Regarding claim 1 Carlson discloses a back-contacting solar cell, wherein the back-contacting solar cell comprises:
a silicon substrate ([0049]-[0050], [0053] Fig. 10C see: base semiconductor 160 of silicon), wherein a non-light receiving surface of the silicon substrate is delimited into a first region and a second region ([0097], Fig. 10C see: rear surface of base semiconductor 160 delimited into base contact regions 281 and emitter contact regions under rear conductive structure 240);
a metal-chalcogen-compound layer ([0097], [0062], [0064], [0077]-[0078], Fig. 10C see: rear emitter layers 235 can be formed from materials which induce a junction in the substrate such as titanium oxides, cesium oxide, zinc oxide, zinc sulfide; molybdenum oxides, tungsten oxides, and copper oxides), wherein the metal-chalcogen-compound layer is deposited within at least the first region of the silicon substrate (Fig. 10 see: rear emitter layers 235 formed under rear conductive structure 240), and a region of the metal- chalcogen-compound layer that corresponds to the first region forms a first-charge-carrier collecting end ([0097], [0062], [0064], [0077]-[0078], Fig. 10C see: rear emitter layers 235 collect and transfer minority carriers from the base region 160 for extraction at rear conductive structure 240); and
a first electrode, wherein the first electrode is correspondingly provided on the first- charge-carrier collecting end ([0049], Fig. 10C see: rear conductive structure 240);
wherein:
a region of the metal-chalcogen-compound layer that corresponds to the second region forms a second-charge-carrier transferring region ([0093]-[0097], Fig. 10C see: rear emitter layers 235 formed within base contact region 281 functionally allow transfer of second charge carrier to reach base carrier selective contact 261 and metal foil 120);
a second electrode is correspondingly provided within the second-charge-carrier transferring region ([0045], [0090] Fig. 10C see: metal layer 268 or dimple 275 of metal foil 120);
a second-charge-carrier selectively-collecting layer is deposited within the second region of the non-light receiving surface of the silicon substrate ([0096], Fig. 10C see: base carrier selective contact 261 in base contact region 281);
the metal-chalcogen-compound layer is deposited on the non-light receiving surface shared by the silicon substrate and the second-charge-carrier selectively-collecting layer ([0093]-[0097], Fig. 10C see: rear emitter layers 235 deposited on surface shared between base carrier selective contact 261 and base semiconductor 160, alternatively where metal-chalcogen-compound layer is not required to be in the second region, Figs. 8B/8D show emitter 262 formed on the same surface of substrate 160 as base contact 261);
if the silicon substrate is an N-type silicon substrate and a second charge carrier is a majority carrier, or if the silicon substrate is a P-type silicon substrate and a second charge carrier is a minority carrier, a material of the metal-chalcogen-compound layer is one of first materials ([0097], [0062], [0064], [0077]-[0078], Fig. 10C see: rear emitter layers 235 can be formed from materials which induce p-type polarity in silicon and allow hole transport include molybdenum oxides, tungsten oxides, and copper oxides); and
if the silicon substrate is a P-type silicon substrate and the second charge carrier is a majority carrier, or if the silicon substrate is an N-type silicon substrate and the second charge carrier is a minority carrier, the material of the metal-chalcogen-compound layer is one of second materials ([0097], [0062], [0064], [0077]-[0078], Fig. 10C see: rear emitter layers 235 can be formed from materials which induce n-type polarity in silicon and allow electron transport such as titanium oxides, cesium oxide, zinc oxide, zinc sulfide).
Regarding the claim 1 limitation “the silicon substrate within the second region is doped to form a second-charge- carrier collecting end” Carlson teaches at para [0053] the silicon substrate is doped either p-type or n-type and is thus also doped within the second region and can be considered to form a second-charge- carrier collecting end. In the alternative where it’s unclear this doping forms a second-charge-carrier collecting end, Choi discloses a back contact solar cell where the silicon substrate further includes a second region doped to form a second-charge- carrier collecting end (Choi, portions bridging pages 13-14 of translation, Figs. 5-6 see: first portions 34a of rear field region 34 with relatively low doping concentration). Choi teaches this doped region prevents recombination in this area of the substrate (Choi, portions bridging pages 13-14 of translation).
Carlson and Choi are combinable as they are both concerned with back contact 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 Carlson in view of Choi such that the second region is doped to form a second-charge- carrier collecting end as in Choi (portions bridging pages 13-14 of translation, Figs. 5-6 see: first portions 34a of rear field region 34 with relatively low doping concentration) as Choi teaches this doped region prevents recombination in this area of the substrate (Choi, portions bridging pages 13-14 of translation).
Regarding claim 6 modified Carlson discloses the back-contacting solar cell according to claim 1, and Carlson discloses wherein:
the first materials are N-type metal chalcogen compounds of a work function greater than or equal to 5eV, or P-type metal chalcogen compounds of a work function less than or equal to 6eV ([0097], [0062], [0064], [0077]-[0078], Fig. 10C see: rear emitter layers 235 can be formed from materials which induce p-type polarity in silicon and allow hole transport include molybdenum oxides, tungsten oxides, and copper oxides which meet the limitation of being N-type with a work function ≥5eV, or P-type with a work function ≤6eV); and
the second materials are metal chalcogen compounds of a work function greater than or equal to 3eV ([0097], [0062], [0064], [0077]-[0078], Fig. 10C see: rear emitter layers 235 can be formed from materials which induce n-type polarity in silicon and allow electron transport such as titanium oxides, zinc oxide, zinc sulfide which are all materials with a work function greater than or equal to 3eV).
Regarding claim 7 modified Carlson discloses the back-contacting solar cell according to claim 1, and Choi further teaches wherein:
a doping concentration of the second-charge-carrier collecting end is greater than or equal to 1015 cm-3, and greater than a doping concentration of the silicon substrate within the first region (Choi, see third paragraph of page 5 of translation see: doping concentrations of the first portions are 1×1016/cm3 to 1×1020/cm3 which is higher than the lightly doped substrate); and
an area of a projection of the second-charge-carrier collecting end on the non-light receiving surface of the silicon substrate accounts for 5% to 45% of a total area of the non- light receiving surface of the silicon substrate (Choi, see top of page 9 of translation see: the area ratio of the rear electric field area 34 to the total area may be 10% to 50% and further may be 10% to 30%).
Regarding claim 8 modified Carlson discloses the back-contacting solar cell according to claim 1, wherein the second-charge-carrier selectively-collecting layer of a thickness of 1-500nm (Carlson, [0080] see: carrier selective layers can be of a thickness that provides the correct electrical and charge transport processes such as from 0.1 to 100 nm which overlaps applicants claimed range with sufficient specificity to be anticipatory or to render applicant’s range obvious) is deposited on the non-light receiving surface within the second region ([0093]-[0097], Figs. 10C and 8B/8D see: base carrier selective contact 261 deposited on rear surface of emitter layers 235 and/or substrate 160).
Regarding claim 10 modified Carlson discloses the back-contacting solar cell according to claim 8, wherein:
if the silicon substrate is an N-type silicon substrate and a second charge carrier is a majority carrier, or if the silicon substrate is a P-type silicon substrate and a second charge carrier is a minority carrier, a material of the second-charge-carrier selectively-collecting layer is selected from a crystalline-silicon material of a work function greater than or equal to 3eV, an amorphous-silicon material of a work function greater than or equal to 3eV, and at least one of second materials, wherein the second materials are metal chalcogen compounds of a work function greater than or equal to 3eV (Carlson, [0078] Fig. 10C see: base carrier selective contact layer (base contact 261) can be selected from n-doped silicon, n-doped polysilicon, n-doped amorphous silicon, n-doped amorphous silicon carbide or p-doped silicon, p-doped polysilicon, p-doped amorphous silicon, p-doped amorphous silicon carbide); and
if the silicon substrate is a P-type silicon substrate and a second charge carrier is a majority carrier, or if the silicon substrate is an N-type silicon substrate and a second charge carrier is a minority carrier, a material of the second-charge-carrier selectively-collecting layer is selected from at least one of first materials, wherein the first materials are N-type metal chalcogen compounds of a work function greater than or equal to 5eV, or P-type metal chalcogen compounds of a work function less than or equal to 6eV.
Regarding claim 12 modified Carlson discloses the back-contacting solar cell according to claim 1, and Carlson discloses wherein:
the second materials are selected from at least one of zinc oxide, tin oxide, titanium oxide, cupric oxide, thallium oxide, cadmium sulfide, molybdenum sulfide, zinc sulfide, molybdenum selenide, copper selenide, niobium-doped cupric oxide, cadmium germanium oxide, iridium zinc oxide and cobalt calcium oxide; (Carlson, [0097], [0062], [0064], [0077]-[0078], Fig. 10C see: rear emitter layers 235 can be formed from materials which induce n-type polarity in silicon and allow electron transport such as titanium oxides, zinc oxide, zinc sulfide) and
the first materials are selected from at least one of molybdenum oxide, tungsten oxide, vanadium oxide, niobium oxide, nickel oxide, mercury-doped niobium oxide and mercury-doped tantalum oxide ([0097], [0062], [0064], [0077]-[0078], Fig. 10C see: rear emitter layers 235 can be formed from materials which induce p-type polarity in silicon and allow hole transport include molybdenum oxides, tungsten oxides).
Regarding claim 13 modified Carlson discloses the back-contacting solar cell according to claim 1, and regarding the claim 13 recitation wherein a transverse-conduction capacity of the metal-chalcogen-compound layer is less than or equal to 1.0X10-3 S/cm Carlson teaches in para [0095] the emitter 235 (metal-chalcogen-compound layer) can further be locally thinned to provide increased local sheet resistance or otherwise prevent shunting from the emitter to any base contact.
As such, the probability of shunting from the emitter to a base contact is a variable that can be modified by varying the transverse-conduction capacity of the metal-chalcogen-compound layer. The court has held that absent criticality or unexpected results, it would be obvious for a person having ordinary skill in the art to optimize a result effective variable for the intended use of the device. Differences in said result effective variable will not support the patentability of subject matter encompassed by the prior art. “Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” See In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). See also MPEP § 2144.05. It would be obvious for a person having ordinary skill in the art to optimize the transverse-conduction capacity of the metal-chalcogen-compound layer locally in the device of modified Carlson to prevent shunting from the emitter to any base contact.
Regarding claim 16 modified Carlson discloses the back-contacting solar cell according to claim 1, wherein:
a tunneling isolating layer is provided between the non-light receiving surface of the silicon substrate and the metal-chalcogen-compound layer (Carlson, Fig. 10C [0060], [0079]-[0080] see: passivation layer 200 which functions as a quantum tunneling layer formed between emitter layer and the substrate); and
Choi discloses such tunneling isolation layers have a thickness of 0.1nm-5nm (Choi, paragraph bridging pages 3-4 of translation, see: tunneling layer thickness of 0.5 nm to 5 nm, for example, 1 nm to 4 nm), and Carlson discloses the tunneling isolating layer is one or more layers (paras [0060], [0079]-[0080]).
Regarding claim 19 modified Carlson discloses the back-contacting solar cell according to claim 16, wherein a material of the tunneling isolating layer is selected from at least one of silicon oxide, silicon nitride, silicon fluoride, silicon fluoride oxide, silicon carbon oxide, aluminium oxide, aluminum fluoride and aluminum oxynitride (Carlson, [0079]-[0080] see: quantum tunneling layer can be silicon dioxide, aluminum oxide, and silicon nitride).
Regarding claim 20 modified Carlson discloses the back-contacting solar cell according to claim 1, wherein:
a second transparent electrically conductive thin film and/or a second work- function regulating layer are provided between the second-charge-carrier collecting end and the second electrode; and both of the second transparent electrically conductive thin film and/or the second work-function regulating layer are located within a projection region of the second-charge-carrier collecting end; and/or
a first transparent electrically conductive thin film and/or a first work-function regulating layer are provided between the first-charge-carrier collecting end and the first electrode; and both of the first transparent electrically conductive thin film and/or the first work-function regulating layer are located within a projection region of the first-charge- carrier collecting end (Carlson, [0066]-[0068] Fig. 10C see: conductive structure 240 can further include a TCO at the interface of emitter 235 and the metal electrode).
Regarding claim 25 modified Carlson discloses the back-contacting solar cell according to claim 20, and the claim 25 recitation “wherein each of the first work-function regulating layer and the second work-function regulating layer is independently selected from at least one of an alkali metal, a transition metal, an alkali- metal halide and a transition-metal halide” is directed to a further limitation on a species anticipated in the rejection of claim 20 and is thus also anticipated by the rejection of claim 20 above.
Regarding claim 36 modified Carlson discloses the back-contacting solar cell according to claim 1, wherein:
the blocking component is a groove (Carlson, [0095] see: rear emitter layers can be locally thinned (groove) to provide increased local sheet resistance or reduced thickness to allow compatibility with subsequently deposited carrier selective contacts and prevent shunting from the emitter to any base contact); and/or the blocking component is an insulator.
Regarding claim 41 modified Carlson discloses the back-contacting solar cell according to claim 1, wherein in the metal-chalcogen-compound layer, the blocking component is provided between the second-charge-carrier transferring region and the first-charge-carrier collecting end (Carlson, [0095] see: rear emitter layers can be locally thinned (groove) to provide increased local sheet resistance or reduced thickness to allow compatibility with subsequently deposited carrier selective contacts and prevent shunting from the emitter to any base contact); and
the blocking component is a groove (Carlson, [0095] see: rear emitter layers can be locally thinned (groove) to provide increased local sheet resistance or reduced thickness to allow compatibility with subsequently deposited carrier selective contacts and prevent shunting from the emitter to any base contact); and/or
the blocking component is a high-resistance body, wherein an electric resistivity of the high-resistance body is not less than 100 times of an electric resistivity of the metal- chalcogen-compound layer.
Regarding claim 43 modified Carlson discloses the back-contacting solar cell according to claim 1, wherein a thickness of the second-charge-carrier selectively-collecting layer is 1-500nm (Carlson, [0080] see: carrier selective layers can be of a thickness that provides the correct electrical and charge transport processes such as from 0.1 to 100 nm which overlaps applicants claimed range with sufficient specificity to be anticipatory or to render applicant’s range obvious).
Regarding claim 53 modified Carlson discloses a back-contacting cell assembly, wherein the back-contacting cell assembly comprises: the back-contacting solar cell according to claim 1 (Carlson, Figs. 13-14 see: the back contact solar cell can be assembled in series with other back contact solar cells).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Carlson (US 2018/0366597), in view of Choi et al (KR 20150029202A, reference made to attached English machine translation) as applied to claims 1, 6-8, 10, 12-13, 16, 19-20, 25, 36, 41, 43, and 53 above, and in further view of KIMOTO (US 2015/0364624).
Regarding claim 5 modified Carlson discloses the back-contacting solar cell according to claim 1, wherein:
the second-charge-carrier selectively-collecting layer is deposited within the second region of the silicon substrate ([0096], Fig. 10C see: base carrier selective contact 261 in base contact region 281);
the metal-chalcogen-compound layer is deposited within the first region (Fig. 10 see: rear emitter layers 235 formed under rear conductive structure 240);
a part of the metal-chalcogen-compound layer that corresponds to the second- charge-carrier selectively-collecting layer forms the second-charge-carrier transferring region ([0093]-[0097], Fig. 10C see: rear emitter layers 235 formed within base contact region 281 functionally allow transfer of second charge carrier to reach base carrier selective contact 261 and metal foil 120); and
the second electrode is correspondingly provided within the second-charge-carrier transferring region ([0045], [0090] Fig. 10C see: metal layer 268 or dimple 275 of metal foil 120).
Carlson does not explicitly disclose the metal-chalcogen-compound layer is deposited on a non-light receiving surface of the second-charge-carrier selectively-collecting layer.
KIMOTO discloses a back contact solar cell comprising an emitter layer deposited within a first region of a substrate and on a non-light receiving surface of a second-charge-carrier selectively-collecting layer (KIMOTO, [0071], Figs. 1 or 12 see: p-type layer 5 formed on a first region 9 and on a back surface of n-type layer 4 in a second region 10 on n-type silicon substrate 1). KIMOTO teaches this base and emitter contact arrangement simplifies manufacture by reducing the need for patterning the emitter (KIMOTO, [0071]).
KIMOTO and modified Carlson are combinable as they are both concerned with the field of back contact 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 Carlson in view of KIMOTO such that the emitter layer 235 (metal-chalcogen-compound layer) of Carlson is arranged in the first region and also deposited on a non-light receiving surface of the second-charge-carrier selectively-collecting layer of Carlson as in KIMOTO (KIMOTO, [0071], Figs. 1 or 12 see: p-type layer 5 formed on a first region 9 and on a back surface of n-type layer 4 in a second region 10 on n-type silicon substrate 1) as KIMOTO teaches this base and emitter contact arrangement simplifies manufacture by reducing the need for patterning the emitter (KIMOTO, [0071]).
Claims 11, and 14-15 are rejected under 35 U.S.C. 103 as being unpatentable over Carlson (US 2018/0366597), in view of Choi et al (KR 20150029202A, reference made to attached English machine translation) as applied to claims 1, 6-8, 10, 12-13, 16, 19-20, 25, 36, 41, 43, and 53 above, and in further view of Heng et al (US 2016/0020342).
Regarding claim 11 modified Carlson discloses the back-contacting solar cell according to claim 1,but does not explicitly disclose wherein the metal chalcogen compounds contain a doping element, and the doping element is selected from at least one of a halogen element, a transition-metal element, an alkali- metal element, a group-III element, a group-IV element and a group-V element.
Heng discloses a back contact solar cell with a metal chalcogen compound layer wherein the metal chalcogen compounds contain a doping element, and the doping element is selected from at least one of a halogen element, a transition-metal element, an alkali- metal element, a group-III element, a group-IV element and a group-V element (Heng, [0065] see: the work function of most CO materials can be tuned by adjusting the carrier concentration and doping such as having Sn (group-IV element) doped indium oxide (ITO) with Sn concentration varied to adjust work function).
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 Carlson in view of Heng such that the metal chalcogen compounds contain a doping element, and the doping element is selected from at least one of a halogen element, a transition-metal element, an alkali- metal element, a group-III element, a group-IV element and a group-V element as in Heng (Heng, [0065] see: the work function of most CO materials can be tuned by adjusting the carrier concentration and doping such as having Sn (group-IV element) doped indium oxide (ITO) with Sn concentration varied to adjust work function) for the purpose of tuning or adjusting the work function of the compounds as in Heng (Heng, [0065]).
Regarding claim 14 modified Carlson discloses the back-contacting solar cell according to claim 1, but does not explicitly disclose wherein:
if the silicon substrate is a P-type silicon substrate and a second charge carrier is a majority carrier, or if the silicon substrate is an N-type silicon substrate and a second charge carrier is a minority carrier:
a fixed-positive-charge density of the metal-chalcogen-compound layer is greater than or equal to 1011cm-2; and/or
an acceptor-defect density of the metal-chalcogen-compound layer is greater than or equal to 1011cm-2; and/or
a limited-charge density of the metal-chalcogen-compound layer is greater than or equal to 1011cm-2; and
if the silicon substrate is an N-type silicon substrate and a second charge carrier is a majority carrier, or if the silicon substrate is a P-type silicon substrate and a second charge carrier is a minority carrier:
a fixed-negative-charge density of the metal-chalcogen-compound layer is greater than or equal to 1012 cm-2; and/or
a donor-defect density of the metal-chalcogen-compound layer is greater than or equal to 1012 cm-2; and/or a limited-charge density of the metal-chalcogen-compound layer is greater than or equal to 1012 cm-2.
Heng discloses a back contact solar cell with a metal chalcogen compound layer wherein if the silicon substrate is a P-type silicon substrate and a second charge carrier is a majority carrier, or if the silicon substrate is an N-type silicon substrate and a second charge carrier is a minority carrier: a fixed-positive-charge density of the metal-chalcogen-compound layer is greater than or equal to 1011cm-2; and/or an acceptor-defect density of the metal-chalcogen-compound layer is greater than or equal to 1011cm-2; and/or a limited-charge density of the metal-chalcogen-compound layer is greater than or equal to 1011cm-2 (Heng, [0065], [0073] see: high work function CO layer can be heavily doped (with metal ions) with a doping concentration of at least 1×1019/cm3 likewise the low work function CO material can include a high dopant concentration); and if the silicon substrate is an N-type silicon substrate and a second charge carrier is a majority carrier, or if the silicon substrate is a P-type silicon substrate and a second charge carrier is a minority carrier: a fixed-negative-charge density of the metal-chalcogen-compound layer is greater than or equal to 1012 cm-2; and/or a donor-defect density of the metal-chalcogen-compound layer is greater than or equal to 1012 cm-2; and/or a limited-charge density of the metal-chalcogen-compound layer is greater than or equal to 1012 cm-2 (Heng, [0065], [0073] see: high work function CO layer can be heavily doped (with metal ions) with a doping concentration of at least 1×1019/cm3 likewise the low work function CO material can include a high dopant concentration).
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 Carlson in view of Heng such that if the silicon substrate is a P-type silicon substrate and a second charge carrier is a majority carrier, or if the silicon substrate is an N-type silicon substrate and a second charge carrier is a minority carrier: a fixed-positive-charge density of the metal-chalcogen-compound layer is greater than or equal to 1011cm-2; and/or an acceptor-defect density of the metal-chalcogen-compound layer is greater than or equal to 1011cm-2; and/or a limited-charge density of the metal-chalcogen-compound layer is greater than or equal to 1011cm-2 as in Heng (Heng, [0065], [0073] see: high work function CO layer can be heavily doped (with metal ions) with a doping concentration of at least 1×1019/cm3 likewise the low work function CO material can include a high dopant concentration); and if the silicon substrate is an N-type silicon substrate and a second charge carrier is a majority carrier, or if the silicon substrate is a P-type silicon substrate and a second charge carrier is a minority carrier: a fixed-negative-charge density of the metal-chalcogen-compound layer is greater than or equal to 1012 cm-2; and/or a donor-defect density of the metal-chalcogen-compound layer is greater than or equal to 1012 cm-2; and/or a limited-charge density of the metal-chalcogen-compound layer is greater than or equal to 1012 cm-2 as in Heng (Heng, [0065], [0073] see: high work function CO layer can be heavily doped (with metal ions) with a doping concentration of at least 1×1019/cm3 likewise the low work function CO material can include a high dopant concentration) for the purpose of tuning or adjusting the work function of the compounds as in Heng (Heng, [0065]).
Regarding claim 15 modified Carlson discloses the back-contacting solar cell according to claim 1, wherein:
a thickness of the metal-chalcogen-compound layer is 1-600nm (Carlson, [0080] see: carrier selective layers can be of a thickness that provides the correct electrical and charge transport processes such as from 0.1 to 100 nm which overlaps applicants claimed range with sufficient specificity to be anticipatory or to render applicant’s range obvious).
Modified Carlson does not explicitly disclose an average light transmittance of the metal-chalcogen-compound layer within a visible-light wave band is greater than or equal to 70%, but Heng teaches a back contact solar cell configuration where the metal-chalcogen-compound layer can be transparent to allow the solar cell to function as a bifacial solar cell (Heng, [0061], [0075]) and thus 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 Carlson in view of Heng such that an average light transmittance of the metal-chalcogen-compound layer within a visible-light wave band is greater than or equal to 70% for the express purpose of functioning in a bifacial cell configuration as in Heng (Heng, [0061], [0075]) by increasing the amount of light passing through the back surface of the solar cell when operating in a bifacial solar panel which can produce more energy than a conventional single-sided solar cell.
Claim 21 is rejected under 35 U.S.C. 103 as being unpatentable over Carlson (US 2018/0366597), in view of Choi et al (KR 20150029202A, reference made to attached English machine translation) as applied to claims 1, 6-8, 10, 12-13, 16, 19-20, 25, 36, 41, 43, and 53 above, and in further view of Nakano et al (WO 2019/216339A1, reference made to US 2021/0057597 as equivalent English translation).
Regarding claim 21 modified Carlson discloses the back-contacting solar cell according to claim 20, but does not explicitly disclose wherein:
both of thicknesses of the first work-function regulating layer and the second work- function regulating layer are 0.1-5nm;
both of work functions of the first work-function regulating layer and the second work-function regulating layer are leV-5.5eV; and
the first transparent electrically conductive thin film is formed by compounding or mixing a transparent electrically conductive material and a work-function regulating material; and/or
the second transparent electrically conductive thin film is formed by compounding or mixing a transparent electrically conductive material and a work-function regulating material.
Nakano discloses a back contact solar cell where the first transparent electrically conductive thin film is formed by compounding or mixing a transparent electrically conductive material and a work-function regulating material; and/or the second transparent electrically conductive thin film is formed by compounding or mixing a transparent electrically conductive material and a work- function regulating material (Nakano, [0053] Fig. 1 see: transparent electrode layers 17p and 17n are formed from transparent conductive oxides obtained by adding, to indium oxide, various metal oxides such as titanium oxide (TiOx), tin oxide (SnOx), tungsten oxide (WOx), and molybdenum oxide (MoOx) at a concentration of 1 wt % or more to 10 wt % or less).
Carlson and Nakano are combinable as they are both concerned with back contact 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 Carlson in view of Nakano such that the first transparent electrically conductive thin film of Heng is formed by compounding or mixing a transparent electrically conductive material and a work-function regulating material; and/or the second transparent electrically conductive thin film of Carlson is formed by compounding or mixing a transparent electrically conductive material and a work- function regulating material as taught by Nakano (Nakano, [0053] Fig. 1 see: transparent electrode layers 17p and 17n are formed from transparent conductive oxides obtained by adding, to indium oxide, various metal oxides such as titanium oxide (TiOx), tin oxide (SnOx), tungsten oxide (WOx), and molybdenum oxide (MoOx) at a concentration of 1 wt % or more to 10 wt % or less) as such a modification would have amounted to the selection of known transparent back electrode compositions for their intended use in a back contact solar cell to accomplish an entirely expected result of charge carrier collection.
Response to Arguments
Applicant's arguments filed 24 November 2025 and 25 November 2025 have been fully considered but they are not persuasive.
Applicant argues on pages 17-21 of the response filed 25 November 2025 regarding the prior art of Carlson that “the rear emitter layer 235 and the base area 261 as a carrier selection contact are not the second-charge-carrier selectively-collecting layer in the present application”, that “the rear emitter layer 235 of Carlson is form by a doping process”, and that “Carlson only mentions that the carrier selective contacts are realized by depositing into a desired pattern by laser transfer, etc., and the carrier selective collection is not realized by the metal-chalcogen-compound layer”.
Applicant’s arguments have been fully considered but are not found persuasive. The examiner respectfully disagrees with applicant’s characterization of what is taught by Carlson. As recited above Carlson at para [0058] states “the rear emitter may be composed of one or more layers (235) that modify the charge carrier concentrations in a portion of the rear of the cell. For example, a rear emitter may be composed of a heterojunction (an interface that occurs between two layers or regions of dissimilar semiconductors) or tunnel junction (a barrier, such as a thin insulating layer or electric potential, between two electrically conducting materials) or a thermally diffused homojunction” and at para [0062] states “the rear emitter forming layers (235) can be accomplished with any suitable selection of materials or processes that accomplish emitter behavior” and thus clearly is not limited to diffused or doped emitters as argued by applicant. Rather the rear emitter layers 235 can be formed from carrier selective contacts (para [0077]) which include metal chalcogen compounds (para [0078] see: rear emitter layers 235 can be formed from materials which induce a junction in the substrate such as titanium oxides, cesium oxide, zinc oxide, zinc sulfide; molybdenum oxides, tungsten oxides, and copper oxides) and as illustrated in Figs. 10B-10C Carlson teaches the rear emitter layers 235 deposited over both a first region (rear emitter layers 235 formed under rear conductive structure 240) and second region of the substrate ([0093]-[0097], Fig. 10C see: rear emitter layers 235 formed within base contact region 281). Regarding applicant’s arguments that Carlson does not teach the claim 1 limitations of “a region of the metal- chalcogen-compound layer that corresponds to the first region forms a first-charge-carrier collecting end” and “a region of the metal-chalcogen-compound layer that corresponds to the second region forms a second-charge-carrier transferring region” the examiner disagrees and as recited above Carlson teaches the rear emitter layers 235 which include a metal- chalcogen-compound layer collect and transfer minority carriers from the base region 160 for extraction at rear conductive structure 240 (paras [0097], [0062], [0064], [0077]-[0078]) and are also deposited within base contact region 281 where substrate majority carriers are collected and thus are considered to functionally allow transfer of second charge carrier to reach base carrier selective contact 261 and metal foil 120. Thus the metal- chalcogen-compound layer as emitter 235 in Carlson in considered to meet these claim limitations.
Regarding applicant’s arguments that Carlson does not teach the claim 1 limitations of “the metal-chalcogen-compound layer is deposited on the non-light receiving surface shared by the silicon substrate and the second-charge-carrier selectively-collecting layer” the examiner disagrees and as recited above Carlson teaches paras [0093]-[0097] and Fig. 10C that the rear emitter layers 235 deposited on surface shared between base carrier selective contact 261 and base semiconductor 160, alternatively where metal-chalcogen-compound layer is not required to be in the second region (see rejections of claim 1 under 35 U.S.C. 112(b) above) Carlson at Figs. 8B/8D show emitter 262 formed on the same surface of substrate 160 as base contact 261.
Applicant further argues Carlson achieves carrier selective contacts through multi-layer foil metal lamination but the examiner respectfully disagrees. The multilayer foil meal lamination of Carlson forms the extraction electrodes of Carlson, analogous to the functions of the claimed first and second electrodes of claim 1. Carrier selective contacts in Carlson include metal-chalcogen-compound materials (see para [0078]) and these carrier selective contacts formed of metal-chalcogen-compound materials can be formed through laser transfer processes (paras [0081]-[0084] see for example formation of titanium oxide using a titanium coated layer (255) and oxygen gas; the formation of molybdenum oxide using a molybdenum coated layer (255) and oxygen gas; and the formation of tungsten oxide using a tungsten coated layer (255) and oxygen gas or exposure of a deposited film of titanium, zinc, aluminum, molybdenum, or tungsten to an oxidizing species).
Applicant’s further arguments and remarks to Carlson are moot as they depend from the arguments rebutted above.
Applicant’s further arguments with respect to claims 1,5-8,10-16,19-21,25,36,41,43 and 53 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
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: KIM et al (US 2018/0212083) also discloses back contact solar cells with metal chalcogen compound layers.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ANDREW J GOLDEN whose telephone number is (571)270-7935. The examiner can normally be reached 11am-8pm.
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ANDREW J. GOLDEN
Primary Examiner
Art Unit 1726
/ANDREW J GOLDEN/ Primary Examiner, Art Unit 1726