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
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.
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 1-2, 4, 7, 9 and 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over CN110459643A; Gu et al.; (hereinafter “Gu”) in view of EP3104397A1; Valentin Dan Mihailetchi; (hereinafter “Mihailetchi”)
Regarding Claim 1, Gu teaches a method for producing a boron emitter on at least one silicon wafer which is arranged in a tube furnace (see attached machine translation of Gu, [0004], boron diffusion process on silicon wafers in tube furnace), comprising in the sequence specified:
a) evacuating the tube furnace to a predetermined pressure ([0008] and [0018], step S1, prepare furnace to a predetermined pressure),
b) flushing reactants, comprising BCl3 and O2, into the tube furnace and adjusting to a further predetermined pressure ([0009] and [0029-0032], step S2, introduce dry O2 and BCl3 into the furnace at pressure such as 150 mbar),
c) stopping the flushing after expiry of a predetermined time and allowing the reactants flushed in to react with each other and with a surface of the silicon wafer over a predetermined duration ([0010-0012] and [0030], step S3/S5, stop reactive gas intake after 120s), and
d) evacuating the tube furnace after expiry of the predetermined duration ([0014], step S7, remove crystalline silicon from the furnace).
Gu does not explicitly teach to form a layer with borosilicate glass on the surface of the silicon wafer.
However, Mihailetchi teaches a method for producing a boron emitter on at least one silicon wafer ([0002]), wherein the method comprises forming a layer with borosilicate glass on the surface of the silicon wafer ([0002-0004], reactive gas reacts with the silicon wafer to form borosilicate glass).
It would have been obvious to one of ordinary skill in the art prior to the effective filling date of the claimed invention to combine Gu with Mihailetchi, as Mihailetchi would simply suggest that a reaction between BCl3 and O2 on silicon wafer in a furnace via a process similar to the process of Gu would naturally produce borosilicate glass on the surface of the silicon wafer according to Mihailetchi, [0005].
Regarding Claim 2, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches steps b) to c) are repeated cyclically ([0023], step S4 comprises repeating steps S2 and S3 for 3-5 cycles).
Gu does not explicitly teach steps b) to d) are repeated cyclically.
However, Mihailetchi teaches steps b) to d) are repeated cyclically ([0028], the diffusion process is repeated cyclically).
It would have been obvious to one of ordinary skill in the art prior to the effective filling date of the claimed invention to modify the invention disclosed by Gu with the teaching of Mihailetchi in order to obtain a more homogenous result from varying process conditions in multiple cycles according to Mihailetchi, [0028].
Regarding Claim 4, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches step c) is carried out at a temperature in the range from 800 to 1.000° C ([0031], furnace temperature in step S3 is 850oC).
Regarding Claim 7, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches the reactants in step b) are flushed into the tube furnace in such a way that they mix with each other in a region of the tube furnace in which the silicon wafer is arranged ([0009-0010], step S2 and S3, dry O2 and BCl3 are introduced into the furnace. Reactive gases react with each other and silicon wafer, see rejection of claim 1).
Regarding Claim 9, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches between steps c) and d), a further step is carried out in which the tube furnace is flushed with an inert gas ([0013], step S6 includes introducing gas such as nitrogen into the furnace).
Regarding Claim 13, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches step c) is carried out at a temperature in a range from 820 to 950°C ([0031], furnace temperature in step S3 is 850oC).
Regarding Claim 14, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches step c) is carried out at a temperature in a range from 850 to 910°C ([0031], furnace temperature in step S3 is 850oC).
Claims 6, 8 and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Gu in view of Mihailetchi, and further in view of US20120083105A1; Yvon Pellegrin et al.; (hereinafter “Pellegrin”).
Regarding Claim 6, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches the reactants in step b) are flushed into the tube furnace, and BCl3 and O2 mix with each other in the tube furnace ([0009-0010], step S2 and S3, dry O2 and BCl3 are introduced into the furnace).
Gu in view of Mihailetchi does not explicitly teach BCl3 is flushed through a supply tube having an outlet end into the tube furnace and O2 is flushed through a further supply tube having an outlet end into the tube furnace, so that BCl3 and O2 mix with each other at the mutually adjacently arranged outlet ends of the supply tube and of the further supply tube in the tube furnace.
However, Pellegrin teaches a method for producing a boron emitter on at least one silicon wafer ([0018], process for boron doping of silicon wafer), BCl3 is flushed through a supply tube (#10-12, Figure 1, intake pipes) having an outlet end into the tube furnace (#3, airtight chamber of furnace) and O2 is flushed through a further supply tube (#10-12) having an outlet end into the tube furnace (#10-12 extend into #3), so that BCl3 and O2 mix with each other at the mutually adjacently arranged outlet ends of the supply tube and of the further supply tube in the tube furnace (Figure 1, [0032] and [0049], reactive gas BCl3 and O2 are introduced into the chamber #3 via adjacent pipes #10-12 and mixed).
It would have been obvious to one of ordinary skill in the art prior to the effective filling date of the claimed invention to modify the invention disclosed by Gu in view of Mihailetchi with the teaching of Pellegrin, as it would be a simple substitution of one known element (introduction of reactive gas into the furnace of Gu) for another (introduction of reactive gas into the furnace using pipe of Pellegrin) to obtain predictable results. See MPEP 2143(I)(B).
Regarding Claim 8, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches during the method, multiple silicon wafers are arranged in a wafer boat in the tube furnace ([0052], wafers are arranged in a boat inside the furnace, see also Figure 1 of Mihailetchi) and are subjected to the method simultaneously.
Gu in view of Mihailetchi does not explicitly teach the distance of the silicon wafers from one another being less than 5 mm.
However, Pellegrin teaches the distance of the silicon wafers from one another being less than 5 mm (Figure 1, [0053], the silicon wafers are arranged on support #2 at interval of 5mm or less).
It would have been obvious to one of ordinary skill in the art prior to the effective filling date of the claimed invention to have selected the overlapping portion of the ranges disclosed by Pellegrin because selection of overlapping portion of ranges has been held to be a prima facie case of obviousness. See MPEP 2131.03(I).
Regarding Claim 17, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches during the method, multiple silicon wafers are arranged in a wafer boat in the tube furnace ([0052], wafers are arranged in a boat inside the furnace, see also Figure 1 of Mihailetchi) and are subjected to the method simultaneously.
Gu in view of Mihailetchi does not explicitly teach the distance of the silicon wafers from one another being less than 3 mm.
However, Pellegrin teaches the distance of the silicon wafers from one another being less than 5 mm (Figure 1, [0053], the silicon wafers are arranged on support #2 at interval of 5mm or less).
It would have been obvious to one of ordinary skill in the art prior to the effective filling date of the claimed invention to modify the invention disclosed by Gu in view of Mihailetchi with the teaching of Pellegrin for the reason set forth in the rejection of claim 8. Additionally, the smaller interval of the wafers improves the application’s performance according to Pellegrin, [0053].
Allowable Subject Matter
Claims 3, 5, 10-12, and 15-16 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
Regarding Claim 3, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches the predetermined pressure is such as 50 mbar ([0018], step S1 is at 50-200 mbar), and the further predetermined pressure is in the range from 20 to 200 mbar ([0009] and [0029-0032], step S2, introduce dry O2 and BCl3 into the furnace at pressure such as 150 mbar).
None of the prior art of record discloses or makes obvious the limitation: “the predetermined pressure is up to 15 mbar” recited in claim 3, in combination of the other claimed method steps.
Regarding Claim 5, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu, the most relevant prior art of record, further teaches the predetermined time is in the range from 10 to 120 sec ([0030], reactive gas introduction in step S2 is 120s), and/or the predetermined duration is in the range from 2 min to 20 min ([0019] or [0031], step S3 is carried out for 180-300s or 3-5 minutes), and/or step a) and/or d) are carried out in a further time such as 300s ([0058]).
None of the prior art of record discloses or makes obvious the limitation: “step a) and/or d) are carried out in a further time in the range from 10 to 120 sec” recited in claim 5, in combination of the other claimed method steps.
Regarding Claim 10, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu, the most relevant prior art of record, further teaches producing the boron emitter on the silicon wafer ([0004], boron diffusion process on silicon wafers in tube furnace, and injecting N2 and oxidizing with O2 are carried out prior to step d) ([0013-0014], step S6 is before step S7).
None of the prior art of record discloses or makes obvious the limitation: “after step d) a step e) of injecting N2 and after step e) a step f) of oxidizing with O2 are carried out” recited in claim 10, in combination of the other claimed method steps.
Regarding Claim 11, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches the predetermined pressure is such as 50 mbar ([0018], step S1 is at 50-200 mbar), and the further predetermined pressure is in the range from 20 to 170 mbar ([0009] and [0029-0032], step S2, introduce dry O2 and BCl3 into the furnace at pressure such as 150 mbar).
None of the prior art of record discloses or makes obvious the limitation: “the predetermined pressure is in a range from 1 to 14 mbar” recited in claim 11, in combination of the other claimed method steps.
Regarding Claim 12, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu further teaches the predetermined pressure is such as 50 mbar ([0018], step S1 is at 50-200 mbar), and the further predetermined pressure is in the range from 20 to 150 mbar ([0009] and [0029-0032], step S2, introduce dry O2 and BCl3 into the furnace at pressure such as 150 mbar).
None of the prior art of record discloses or makes obvious the limitation: “the predetermined pressure is in a range from 7 to 12 mbar” recited in claim 12, in combination of the other claimed method steps.
Regarding Claim 15, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu, the most relevant prior art of record, further teaches the predetermined time is in the range from 20 to 100 sec ([0030], reactive gas introduction in step S2 is 120s), and/or the predetermined duration is in the range from 3 min to 15 min ([0019] or [0031], step S3 is carried out for 180-300s or 3-5 minutes), and/or step a) and/or d) are carried out in a further time such as 300s ([0058]).
None of the prior art of record discloses or makes obvious the limitations: “the predetermined time is in a range from 20 to 100 sec” and “step a) and/or d) are carried out in a further time in the range from 20 to 100 sec” recited in claim 15, in combination of the other claimed method steps.
Regarding Claim 16, Gu in view of Mihailetchi teaches the method as described in claim 1, wherein Gu, the most relevant prior art of record, further teaches the predetermined time is in the range from 30 to 60 sec ([0030], reactive gas introduction in step S2 is 120s), and/or the predetermined duration is in the range from 5 min to 10 min ([0019] or [0031], step S3 is carried out for 180-300s or 3-5 minutes), and/or step a) and/or d) are carried out in a further time such as 300s ([0058]).
None of the prior art of record discloses or makes obvious the limitations: “the predetermined time is in a range from 30 to 60 sec” and “step a) and/or d) are carried out in a further time in the range from 30 to 60 sec” recited in claim 16, in combination of the other claimed method steps.
Response to Amendments/Arguments
Applicant's arguments, pages 9-11 of the remarks, filed 02/24/2026, with respect to 35 U.S.C 103 rejection of claim 1 as unpatentable over CN110459643A; Gu et al.; (hereinafter “Gu”) in view of EP3104397A1; Valentin Dan Mihailetchi; (hereinafter “Mihailetchi”) have been fully considered and are not found persuasive.
Applicant argues on pages 9-11 of the remarks that the Non-final Office Action, filed 12/11/2025, hereinafter “Non-final” incorrectly articulates the rationale to combine Gu and Mihailetchi by substitution of known elements to achieve the claimed invention: “forming a layer with borosilicate glass on the surface of the silicon wafer” recited in claim 1. While examiner acknowledges the applicant’s arguments, examiner respectfully disagrees.
In order to provide further clarification, the rationale for combining Gu and Mihailetchi in the rejection of claim 1 has been modified (See U.S.C. 103 rejection of claim 1 above). No new ground(s) of rejection has been introduced. As detailed in the rejection above, Gu teaches a boron diffusion process comprising at least evacuating and preparing a furnace, feeding reactants BCL3 and O2 into the furnace containing a silicon wafer, allowing the reactants and silicon wafer to react inside the furnace before removing the crystalline silicon wafer from the furnace. Mihailetchi teaches a similar process (see also claim 1 of Mihailetchi) that additionally recites a reaction between BCL3 and O2 on silicon wafer in the furnace naturally producing borosilicate glass on the surface of the silicon wafer (see [0005] of Mihailetchi). Although the Non-final provided a rationale to combine Gu and Mihailetchi by substitution of the method steps of allowing the reactants to react in the furnace, one of ordinary skill in the art would understand the combination to only suggest that Gu (despite being silent on the resultant) would naturally produce at least borosilicate glass on the silicon wafer through the described method step in a similar process to that of Mihailetchi. Hence, the rejection is maintained.
Conclusion
THIS ACTION IS MADE FINAL. 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 TIEN TRAN whose telephone number is (571)272-6967. The examiner can normally be reached Monday-Thursday 9:00 am - 6:00 pm ET.
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/TIEN TRAN/Examiner, Art Unit 2812
/CHRISTINE S. KIM/Supervisory Patent Examiner, Art Unit 2812
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