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 .
DETAILED ACTION
Preliminary Amendment, received 12/22/2023, has been entered.
Claims 1-20 are presented for examination.
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.
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.
Claim(s) 1-8, 11, 13 and 15-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Qiu et al. (CN215118914U, provided with IDS received 12/22/2023, using English translation provided by Examiner), hereafter referred to as Qiu, in view of Huang et al. (CN111106183A, provided with IDS received 12/22/2023, using English translation provided by Examiner), hereafter referred to as Huang.
As to claim 1, Qiu discloses a preparation process of a passivated contact battery (fig 2 and pages 4-5), a preparation of a backside field passivated structure thereof comprising:
growing a tunneling oxide layer (fig 2, S4; page 4) on a backside of a silicon wafer (S1);
growing an intrinsic silicon carbide layer (S2; page 5) on a surface of the tunneling oxide layer (S4); and
growing a doped silicon carbide layer (S3; page 5) on a surface of the intrinsic silicon carbide layer (S2).
Qiu does not explicitly disclose that the doping for the doped silicon carbide layer is phosphorus; and performing annealing treatment to form a covalent bond between phosphorus and silicon carbide in the phosphorus-doped silicon carbide layer.
Nonetheless, Huang discloses a method for preparing a backside passivated contact solar cell using a phosphorous doped silicon carbide layer (fig 4, layer 8) on a silicon dioxide layer (layer 7) which is on a silicon substrate (1); and performing annealing treatment to form a covalent bond between phosphorus and silicon carbide in the phosphorus-doped silicon carbide layer (page 7).
It would have been obvious to one of ordinary skill in the art before the effective filing of the claimed invention to use phosphorus as the doping in Qiu as taught by Huang since choosing one of the known dopant types for its intended function would have been obvious to one of ordinary skill in the art, additionally, performing the annealing process of Huang in the passivation structure of Qiu improves the crystallinity and passivation of the backside structure.
As to claim 2, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu further discloses wherein a thickness of the intrinsic silicon carbide layer ranges from 5 nm to 80 nm (page 5).
As to claim 3, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu further discloses wherein a thickness of the doped silicon carbide layer is greater than 10nm (page 4) and Huang discloses ranges from 20 nm to 200 nm (page 4).
As to claim 4, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu further discloses wherein a total thickness of the intrinsic silicon carbide layer and the phosphorus-doped silicon carbide layer is less than or equal to 200 nm (page 4).
As to claim 5, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu further discloses wherein in the step of growing the intrinsic silicon carbide layer, the intrinsic silicon carbide layer is deposited by a plasma enhanced chemical vapor deposition method (page 5).
As to claim 6, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu further discloses wherein in the step of growing the intrinsic silicon carbide layer, CH4 and SiH4 are introduced for reactive deposition, wherein a volume ratio of CH4 and SiH4 is 1:(1 to 10) (page 5).
Qiu does not disclose that H2 is also introduced for reactive deposition.
Nonetheless, Huang further discloses that H2 is introduced for reactive deposition (page 7).
It would have been obvious to one of ordinary skill in the art before the effective filing of the claimed invention to include H2 in the PECVD of Qui as taught by Huang since this will improve the chemical reaction and passivate defects.
As to claim 7, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Huang further discloses wherein in the step of growing the phosphorus-doped silicon carbide layer, CH4, SiH4, PH3, and H2 are introduced for reactive deposition (page 7), and Qiu further discloses wherein a volume ratio of CH4 and SiH4 is 1:(1 to 10) (page 5).
As to claim 8, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Huang further discloses wherein in the step of performing annealing treatment, an annealing temperature ranges from 600°C to 1000°C, and an annealing time ranges from 10 min to 60 min (page 7).
As to claim 11, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Huang further discloses wherein the annealing treatment is performed using a tubular annealing furnace, and an annealing atmosphere is nitrogen (N2) or oxygen (02) (page 7).
As to claim 13, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu does not disclose the front side layers.
Nonetheless, Huang further discloses depositing an aluminum oxide film and a silicon nitride film on a front side (page 8), wherein the aluminum oxide (AlOx) film is deposited by a plasma enhanced atomic layer deposition or PECVD (page 4), and the silicon nitride (SiNx) film is deposited by PECVD (page 5).
It would have been obvious to one of ordinary skill in the art before the effective filing of the claimed invention to form the aluminum oxide and silicon nitride films on the front side of Qiu as taught by Huang since this will provide improved passivation and reflective properties.
As to claim 15, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Huang further discloses wherein in the step of growing the tunneling oxide layer, the tunneling oxide layer with a thickness of 0.5 nm to 2 nm is formed by PEALD or PECVD (pages 7-9).
As to claim 16, Qiu discloses a passivated contact battery (fig 2 solar battery), comprising:
a silicon wafer (fig 2, S1; page 4), and
a tunneling oxide layer (S4; page 4),
an intrinsic silicon carbide layer (S2; page 4), and
a doped silicon carbide layer (S3; page 4) that are successively stacked on a backside of the silicon wafer (S1).
Qiu does not explicitly disclose that the doped silicon carbide layer is doped with phosphorus.
Nonetheless, Huang discloses a method for preparing a backside passivated contact solar cell using a phosphorous doped silicon carbide layer (fig 4, layer 8) on a silicon dioxide layer (layer 7) which is on a silicon substrate (1).
It would have been obvious to one of ordinary skill in the art before the effective filing of the claimed invention to use phosphorus as the doping in Qiu as taught by Huang since this provides good electrical performance for the passivated contact battery.
As to claim 17, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Huang further discloses wherein in the step of growing the phosphorus-doped silicon carbide layer, the phosphorus-doped silicon carbide layer is deposited by a plasma enhanced chemical vapor deposition method (page 7).
As to claim 18, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu further discloses wherein a thickness of the intrinsic silicon carbide layer ranges from 5 nm to 50 nm (page 5).
As to claim 19, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Huang further discloses wherein a thickness of the phosphorus- doped silicon carbide layer ranges from 100 nm to 150 nm (page 8).
As to claim 20, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Huang further discloses wherein in the step of performing annealing treatment, an annealing temperature is 800°C (page 7), Huang does not disclose the range from 900°C to 940°C.
It would have been obvious to one of ordinary skill in the art before the effective filing of the claimed invention to optimize the annealing temperature within the range of 900-940C from the temperature of 800C taught by Huang since discovering the optimum or workable range relies on only ordinary and routine skill in the art.
Claim(s) 9-10 and 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Qiu in view of Huang and further in view of Wu et al. (CN113972302A, provided on IDS received 03/03/2025, using English translation provided by Examiner). hereafter referred to as Wu.
As to claim 9, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu in view of Huang do not disclose wherein after the step of growing the phosphorus-doped silicon carbide layer and prior to the step of performing annealing treatment, the preparation process further comprises: growing a SiOx mask layer on a surface of the phosphorus-doped silicon carbide layer.
Nonetheless, Wu discloses wherein the process further comprises growing a SiOx mask layer on a surface of the doped silicon layer before an annealing treatment (page 5).
It would have been obvious to one of ordinary skill in the art before the effective filing of the claimed invention to include the mask layer of Wu in the process of Qiu in view of Huang since this will provide improved protection to the backside of the device.
As to claim 10, Qiu in view of Huang and Wu disclose the preparation process according to claim 9 (paragraphs above).
Wu further discloses wherein in the step of growing the SiOx mask layer on the surface of the doped silicon layer, SiH4 and N20 are introduced to deposit the SiOx mask layer by PECVD (pages 7-8), and a thickness of the SiOx mask layer ranges from 10 nm to 50 nm (page 9).
As to claim 12, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu further discloses firstly removing an oxide layer wraparound a front side during each step of the preparation of the backside field passivated structure and an oxide layer formed during annealing by a chain hydrofluoric acid (HF)(pages 4-5).
Qiu in view of Huang do not disclose removing a front side silicon carbide wraparound layer by transferring to an alkaline bath.
Nonetheless, Wu further discloses removing a front side silicon layer wraparound layer by transferring to an alkaline bath (page 4).
It would have been obvious to one of ordinary skill in the art before the effective filing of the claimed invention to remove the silicon carbide wraparound layer from the front side of the device by the alkaline bath as taught by Wu since this will ensure that the doped silicon layer is only present on the backside surface of the device and does not contaminate the front surface of the device.
Claim(s) 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Qiu in view of Huang and further in view of Ren et al. (US Pub. No. 2024/0014340 A1), hereafter referred to as Ren.
As to claim 14, Qiu in view of Huang disclose the preparation process according to claim 1 (paragraphs above).
Qiu in view of Huang do not disclose depositing a backside silicon nitride film, wherein a SiNx film is deposited by PECVD.
Nonetheless, Ren discloses depositing a backside silicon nitride film, wherein a SiNx film is deposited by PECVD ([0006]).
It would have been obvious to one of ordinary skill in the art before the effective filing of the claimed invention to form the backside silicon nitride film in the device of Qiu in view of Huang as taught by Ren since this will reduce warpage.
Pertinent Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. US Pub. No. 2024/0395963 A1.
Conclusion
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/SHAUN M CAMPBELL/Primary Examiner, Art Unit 2893 5/6/2026
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