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 1-2, 4-21 are currently pending.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 10/20/2025 has been entered.
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.
The term “adjacent” in claim 1 is a relative term which renders the claim indefinite. The term “adjacent” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Claim 1 recites “adjacent”. It is unclear how far “adjacent” is.
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.
Claim(s) 1-6, 9-11, 15-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bett et al (PG pub 20150380591), and further in view of Wanlass (Pat no. 5322572) or alternatively Krut et al (PG pub 20060048811)
Regarding claim 1, Bett teaches a multijunction solar cell comprising a semiconductor body [fig 7] including:
a tandem vertical stack of at least an upper solar subcell (11,13) comprising a first surface having a first surface area, a second solar subcell (12) comprising second surface having second surface area, and a bottom solar subcell (the solar cell is a multi-junction cell having 3 to 6 subcells stacked one above another, it is considered below subcell 12 there would be a bottom subcell) [fig 6 7 9 9A para 82]
a plurality of openings in the tandem vertical stack extending from the upper solar subcell down to the second subcell so that the second solar subcell is exposed to the incident light through such openings wherein the openings have a collective surface area in a plane parallel to the second surface [fig 7 9 9A]; and
A plurality of grid lines disposed over the upper solar subcell but not over the second solar subcell, such that no interconnections or contacts are present in the openings in the upper solar subcell [fig 8 9 9A]
Bett et al teaches there being a lateral conduction layer being used for lateral current flow [para 104], but Bett et al does not teach the LCL disposed adjacent to and directly above the second subcell of each respective one of the regions.
Wanlass teaches a multijunction cell comprising the LCL being disposed adjacent to and directly above the second subcell of each respective one of the regions [fig 7].
It would have been obvious to one of ordinary skill in the art at the time the invention was filed to have the LCL of Bett et al to be disposed adjacent to and directly above the second subcell of each respective one of the regions as taught by Wanlass for lateral current flow. As for combination, a plurality of openings in the tandem vertical stack extending to the level of the lateral conduction layer.
Modified Bett et al teaches the claimed limitation as set forth above, but modified Bett et al does not teach the collective surface area constitutes between 5% and 10% of the second surface of the solar cell.
Wanlass teaches the area of the upper subcells would be optimized for matching the current densities of two subcells (col 8 lines 36-47). Thus, the percentage of exposed area (the exposed area is the area where upper subcell is not being disposed on) would have been considered a result effective variable by one having ordinary skill in the art at the time the invention was made. It is noted that the opening area affected the collective surface area.
As such, without showing unexpected results, the claimed percentage of exposed area of the second surface area of the solar cell 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 percentage of the opening area in the apparatus of Wanlass such that the collective surface area to arrive the claimed range to match the current densities of two subcells (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).
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The instant application recites “beginning of life refers to the time at which the PV power system initially deployed in operation” and the current matching in the top subcell with the current in the second subcell at end-of-life (EOL) [para 41]. Modified Bett et al teaches the tandem solar cell where the upper subcell has the claimed thickness and structure. Also, the light hits the upper subcell first which the upper solar cell would absorb the amount of the wavelength, after that the wavelength that the upper subcell would not absorb will go through the second subcell and third cell for absorbing. thus, at the beginning of life the upper subcell would generate the electricity (current) first while the remaining radiation has to come down through the second sucbelll and third subcell for generating electricity. As a result, the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell, thereby increasing the overall power output of the solar cell at the end-of-life.
Alternatively rejection:
Modified Bett et al teaches the upper solar subcell having thickness, but modified Bett does not teach the thickness of the upper solar subcell provides at the beginning-of-life current collection per unit area in the upper solar subcell that is greater than the current collection per unit area in the second solar subcell.
Krut teaches the thickness of the upper subcell being controlled for desired current [fig 2 para 24-27].
The court has held that absent evidence of criticality or unexpected results, optimization of a result effective variable will not support the patentability of subject matter encompassed by the prior art."[W]here 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). The discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art. See In re Boesch, 205 USPQ 215 (CCPA 1980) (see MPEP§ 2144.05, II.).
Therefore, absent the showing of criticality or unexpected results, it would be obvious to one of ordinary skill in the art to adjust the thickness of the upper subcell such that the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell, for maximizing efficiency [para 25].
The instant application recites “beginning of life refers to the time at which the PV power system initially deployed in operation. Modified Bett et al teaches the tandem solar cell where the upper subcell has the claimed thickness. Also, the light hits the upper subcell first which the upper solar cell would absorb the amount of the wavelength, after that the wavelength that the upper subcell would not absorb will go through the second subcell and third cell for absorbing. thus, at the beginning of life the upper subcell would generate the electricity (current) first while the remaining radiation has to come down through the second sucbelll and third subcell for generating electricity. As a result, the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell, thereby increasing the overall power output of the solar cell at the end-of-life.
Regarding claim 2, modified Bett et al teaches first surface has a continuous periphery and the plurality of openings in the upper solar subcell are disposed adjacent to around the periphery[fig 7].
Regarding claim 4, modified Bett et al teaches the openings are constituted by a plurality of substantially rectangular strips [fig 6 7 para 74] (para 74 teaches the PV cell and subcell would be rectangular, square or circle).
Regarding claim 5, modified Bett et al teaches each strip is substantially parallel to each of the respective sides of the multijunction solar cell [fig 6 7]
Regarding claim 6, the solar cell is substantially rectangular and the openings are constituted by four continually connected regions disposed adjacent to each side of the multijunction solar cell [fig 6 7 para 74].
Regarding claim 9, modified Bett et al teaches the claimed limitation as set forth above, but modified Bett et al does not teach the thichkness of the upper subcell.
Wanlass teaches the thickness of the subcell being adjusted for the matching current densities between cell (col 8 lines 36-47). Thus, the thickness 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 claimed thickness of the upper subcell 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 upper subcell of Wanlass to arrive the claimed range to match the current densities between two subcells (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).
Regarding claim 10, since modified Bett et al teaches solar cell having the claimed structure and material, it would considertd the EOL to BOL ratio of the short circuit current of the second subcell being greater than 95%.
Regarding claim 11, since modified Bett et al teaches solar cell having the claimed structure and material, it is considered that the short circuit current density in the upper solar subcell in the first semiconductor region is approximately equal to the short circuit density of the second subcell in the second semiconductor region.
Regarding claim 15, modified modified Bett et al teaches the current collection in the upper solar subcell is designed to match with the current collection in the second solar subcell at the end-of-life (EOL) (Wanlass, col 8 lines 36-47).
Regarding claim 16, modified Bett et al teaches the plurality of openings constitute a plurality of discrete spaced-apart openings [fig 7]
Regarding claim 17, the plurality of openings is constituted by a plurality of continuously connected regions [fig 7].
Regarding claim 18, the openings completely surround the plurality of grid lines [fig 7]
Regarding claim 19, one or more of the openings are constituted by a substantially rectangular strips which are arranged substantially parallel to the plurality of grid lines [fig 7].
Regarding claim 20, Bett teaches a multijunction solar cell comprising a semiconductor body [fig 7] including:
Forming a tandem vertical stack of at least an upper solar subcell, a second solar subcell, and a bottom solar subcell [fig 6 7 9 9A]
Forming a plurality of openings in the tandem vertical stack extending from the upper solar subcell down to the second subcell so that the second solar subcell is exposed to the incident light through such openings [fig 7 9 9A]; and
Forming a plurality of grid lines disposed over the upper solar subcell but not over the second solar subcell, such that no interconnections or contacts are present in the openings in the upper solar subcell [fig 8 9 9A]
Bett et al teaches there being a lateral conduction layer being used for lateral current flow [para 104], but Bett et al does not teach the LCL disposed adjacent to and directly above the second subcell of each respective one of the regions.
Wanlass teaches a multijunction cell comprising the LCL being disposed adjacent to and directly above the second subcell of each respective one of the regions [fig 7].
It would have been obvious to one of ordinary skill in the art at the time the invention was filed to have the LCL of Bett et al to be disposed adjacent to and directly above the second subcell of each respective one of the regions as taught by Wanlass for lateral current flow. As for combination, a plurality of openings in the tandem vertical stack extending to the level of the lateral conduction layer.
Modified Bett et al teaches the claimed limitation as set forth above, but modified Bett et al does not teach the collective surface area constitutes between 5% and 10% of the second surface of the solar cell.
Wanlass teaches the area of the upper subcells would be optimized for matching the current densities of two subcells (col 8 lines 36-47). Thus, the percentage of exposed area (the exposed area is the area where upper subcell is not being disposed on) would have been considered a result effective variable by one having ordinary skill in the art at the time the invention was made. It is noted that the opening area affected the collective surface area.
As such, without showing unexpected results, the claimed percentage of exposed area of the second surface area of the solar cell 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 percentage of the opening area in the apparatus of Wanlass such that the collective surface area to arrive the claimed range to match the current densities of two subcells (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).
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The instant application recites “beginning of life refers to the time at which the PV power system initially deployed in operation” and the current matching in the top subcell with the current in the second subcell at end-of-life (EOL) [para 41]. Modified Bett et al teaches the tandem solar cell where the upper subcell has the claimed thickness and structure. Also, the light hits the upper subcell first which the upper solar cell would absorb the amount of the wavelength, after that the wavelength that the upper subcell would not absorb will go through the second subcell and third cell for absorbing. thus, at the beginning of life the upper subcell would generate the electricity (current) first while the remaining radiation has to come down through the second sucbelll and third subcell for generating electricity. As a result, the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell, thereby increasing the overall power output of the solar cell at the end-of-life.
Alternatively rejection:
Modified Bett et al teaches the upper solar subcell having thickness, but modified Bett does not teach the thickness of the upper solar subcell provides at the beginning-of-life current collection per unit area in the upper solar subcell that is greater than the current collection per unit area in the second solar subcell.
Krut teaches the thickness of the upper subcell being controlled for desired current [fig 2 para 24-27].
The court has held that absent evidence of criticality or unexpected results, optimization of a result effective variable will not support the patentability of subject matter encompassed by the prior art."[W]here 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). The discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art. See In re Boesch, 205 USPQ 215 (CCPA 1980) (see MPEP§ 2144.05, II.).
Therefore, absent the showing of criticality or unexpected results, it would be obvious to one of ordinary skill in the art to adjust the thickness of the upper subcell such that the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell, for maximizing efficiency [para 25].
The instant application recites “beginning of life refers to the time at which the PV power system initially deployed in operation. Modified Bett et al teaches the tandem solar cell where the upper subcell has the claimed thickness. Also, the light hits the upper subcell first which the upper solar cell would absorb the amount of the wavelength, after that the wavelength that the upper subcell would not absorb will go through the second subcell and third cell for absorbing. thus, at the beginning of life the upper subcell would generate the electricity (current) first while the remaining radiation has to come down through the second sucbelll and third subcell for generating electricity. As a result, the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell, thereby increasing the overall power output of the solar cell at the end-of-life.
Regarding claim 21, modified Bett teaches the second surface area being different from the first surface area.
Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Bett et al (PG pub 20150380591) and Wanlass (Pat No. 5322572) and Krut et al (PG pub 20060048811) and further in view of Newman (Pat No. 8187907).
Regarding claim 7, modified Bett et al teaches the claimed limitation, but modified Bett et al does not teach the DBR having the structure as claimed.
Newman teaches a distributed Bragg reflector (DBR) structure disposed below the second solar subcell and above the third solar subcell, wherein the DBR structure includes a first DBR layer composed of a plurality of n type or p type AlxGai-xAs layers, and a second DBR layer disposed over the first DBR layer and composed of a plurality of n or p type AlyGai-yAs layers, where 0<x< l,0<y< 1, and y is greater than x (col 8 lines 18-37).
It would have been obvious to one of ordinary skill in the art at the time the invention was filed to add the DBR of Newman between the second and third solar subcell as taught by Bett et al for increasing the short circuit current by maintaining or exceeding the absorption volume (col 8 lines 42-47).
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Bett et al (PG pub 20150380591) and Wanlass (Pat No. 5322572) or alternatively Krut et al (PG pub 20060048811) as applied to claim 1 above and further in view of Gray et al (PG pub 20100089440)
Regarding claim 8, modified Bett et alteach the lateral conduction layer as set forth above, but modified Bett et al does not teach material of lateral conduction layer as claimed.
Gray et al teaches a multijunction layer comprising lateral conduction layer being made of InGaP [para 10].
It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the material of lateral conduction layer as taught by modified Bett et al to be made of InGaP as taught by Gray et al since Selection of a known material based on its suitability for its intended use, supports prima facie obviousness determination (MPEP2144.07).
Claim 12-14 are rejected under 35 U.S.C. 103 as being unpatentable over Bett et al (PG pub 20150380591) and Wanlass (Pat No. 5322572) or alternatively Krut et al (PG pub 20060048811) and further in view of Jones-Albertus et al (PG pub 20130122638).
Regarding claim 12-13, modified Bett et al teaches a third subcell being disposed below the second one, and fourth subcell disposed below the third one [para 103], but modified Bett et al does not teach the material of the upper solar subcell and the second solar subcell.
Jones teaches a multijunction solar cell comprising AlGaInP uppermost subcell with bandgap of 1.9 to 2.2eV, a second (Al, In)GaAs subcell with (Al, In)GaAs base and emitter layer with band gap of 1.4 to 1.7eV, a third subcell being disposed below the second one, and fourth subcell disposed below the third one [fig 16].
It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the material of the first upper and second subcell as taught by modified Bett et al to be made of the same material of the uppermost subcell and second subcell of Jones since Selection of a known material based on its suitability for its intended use, supports prima facie obviousness determination (MPEP2144.07).
Regarding claim 14, modified Bett et al teaches a third subcell being disposed below the second one, and fourth subcell disposed below the third one [para 103], but modified Bett et al does not teach the material of the upper solar subcell and the second solar subcell.
Jones teaches a multijunction solar cell comprising AlGaInP uppermost subcell with bandgap of 1.9 to 2.2eV, a second (Al, In)GaAs subcell with (Al, In)GaAs base and emitter layer with band gap of 1.4 to 1.7eV, a third subcell being disposed below the second one, and fourth subcell disposed below the third one [fig 16].
It would have been obvious to one of ordinary skill in the art at the time the invention was filed to modify the material of the first upper and second subcell as taught by modified Bett et al to be made of the same material of the uppermost subcell and second subcell of Jones since Selection of a known material based on its suitability for its intended use, supports prima facie obviousness determination (MPEP2144.07).
modified Bett et al teaches AlGaInP uppermost subcell with bandgap of 1.9 to 2.2eV having first thickness, a second (Al, In)GaAs subcell with (Al, In)GaAs base and emitter layer with band gap of 1.4 to 1.7eV having second thickness which is overlapped the claimed range. According to MPEP 2144.05, in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
However, modified Bett et al does not teach the second thickness being greater than the first thickness.
Wanlass teaches the thickness of the subcell being adjusted for the matching current densities between cell (col 8 lines 36-39). Thus, the thickness 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 claimed thickness of the upper subcell 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 upper subcell of Wanlass to arrive the claimed range such that the second thickness greater than the first thickness to match the current densities between two subcells (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).
Response to Arguments
Applicant's arguments filed 10/20/2025 have been fully considered but they are not persuasive. The applicant argues in substance:
amended claim 1 specifies that the upper solar subcell and the second solar subcell are not initially current matched. Thus, the cited references fail to teach or suggest a multijunction solar cell having all of the features of amended claim 1.
The examiner respectfully disagrees. Claim 1 requires the top cell having thickness and that thickness would made the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell. Modified Bett et al teaches the tandem solar cell where the upper subcell has the claimed thickness and claimed structure. Thus, modified Bett et al teaches the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell. It is noted that even Bett et al teaches the current matching, the current matching would be the result at the end of life (para 41 of instant application shows the current matching takes places at the end of life). Also, the claim does not require specific thickness at which the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell.
Wanlass and Krut does not teach the non-current matching at the beginning of life.
The examiner respectfully disagrees. Krut is applied to teach the claimed thickness. Thus, it would be obvious to one of ordinary skill in the art to adjust the thickness of the upper subcell such that the current collection in the upper solar subcell at the beginning-of-life has greater current collection per unit area than the current collection per unit area in the second solar subcell, for maximizing efficiency [para 25]. Wanlass is not applied to teach the thickness.
Conclusion
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/UYEN M TRAN/Primary Examiner, Art Unit 1726