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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 8/7/26 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.
Claims 12 and 17 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.
Claims 12 and 17 recite “the brazing material includes Ag, Cu, and Ti” while claim 1 recites “the brazing material includes one or two of Sn or In”. It is unclear if the brazing material in claims 12 and 17 is to further include Ag, Cu, and Ti or to replace the Sn/In of claim 1. For the purposes of this examination, this limitation will be interpreted as further includes.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 2, 4, 6, 7, 9-13, and 15-21 are rejected under 35 U.S.C. 103 as being unpatentable over Kaga et al. (US 2009/0101392 A1) in view of brazing.com “Active Brazing Alloys”, Yuasa et asl. (US 2022/0225498 A1), and Shearer et al. (US 2016/068103 A1).
Regarding claim 1, Kaga teaches:
A method for manufacturing a bonded body [circuit board (1); figure 1], comprising:
a process of disposing a brazing material [Ag-Cu-Ti brazing paste (5); 0047, 0060] between a ceramic substrate [substrate (2)] and a copper plate [copper circuit plate (3)], the copper plate including a surface perpendicular to a direction from the ceramic substrate toward the copper plate [see figure 1]; and
a bonding process of bonding the ceramic substrate and the copper plate at a bonding temperature of not more than 800 °C [600-950°C or 750°C; 0058, 0047].
Kaga does not teach:
after the bonding process, a number percentage of copper crystal grains having major diameters greater than 400 μm in three 5 mm×5 mm regions included in the surface being not less than 0% and not more than 5%;
wherein B/A ≤ 10 is satisfied, A (μm) is an average grain size of the copper plate before the bonding process, and B (μm) is an average grain size of the copper plate after the bonding process;
wherein an average value of the major diameters of the copper crystal grains in the three regions is not less than 30 μm and not more than 300 μm;
wherein the brazing material has a melting point of not more than 700 °C;
wherein a largest endothermic peak of a DSC curve of the brazing material is at not more than 700°C; and
wherein the brazing material includes one or two of Sn or In, and a powder particle size of the Sn or the In is largest among powder particle sizes of components included in the brazing material.
Note that the applicant achieves the claimed number percentage by having an average copper crystal grain size of 10-200 µm prior to brazing and brazing in the claimed temperature range with Ag-Cu-Ti-Sn/In braze.
Concerning the melting point and endothermic peak:
As noted above, Kaga teaches Ag-Cu-Ti brazing paste (5); 0047, 0060.
brazing.com teaches active brazing materials wherein SA A-44Ti-Active has an Ag-Cu-Ti-In composition with a melting point of 612°C.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate SA A-44Ti into Kaga in order to be at the lower bonding/brazing temperature of Kaga. Additionally, one would have been motivated to do so in order to reduce grain growth and/or heat input into the workpieces.
In doing so, the endothermic peak is below 700°C since the melting point is below 700°C.
Concerning the In:
Yuasa teaches Ag-Cu-Ti(H)-Sn/In active braze pastes wherein the paste comprises powders of these wherein the diameter of the Ag particles is 0.5-8µm, the diameter of the Cu particles is 0.5-8µm, the diameter of the Sn/In particles is 0.8-10µm; 0150-0156, 0199.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to make the brazing.com paste with powders as taught by Yuasa since it is known to do so.
Additionally, while Yuasa is silent as to the diameter of the Ti(H) it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention use diameters in a similar range, 0.5-8µm, to the others since this is a known effective diameter size, minus any unexpected results. Note that Yuasa allows the diameter size of the particles to vary and for any one of them to be the largest but also only allows for Sn/In to be 8-10µm which makes them the largest.
Shearer teaches that larger HMP particles react slower with LMP particles than smaller HMP particles; 0094.
Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to make the In particles larger than all of the other HMP particles in order to increase the reaction rate between them.
Concerning the average copper crystal grain size of 10-200 µm prior to brazing:
Yuasa teaches a ceramic-copper composite comprising copper layer (2), brazing material layer (3), and ceramic layer (1), wherein the average copper crystal grain size of the copper plate prior to brazing is 20-200 µm in order to control oozing of brazing material; 0076-0077.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to incorporate the Yuasa average copper crystal grain size concept into Kaga in order to control oozing.
Since the prior art process, i.e. the process based on the combined prior art references above, is identical to the claimed process it is the examiner’s position that the prior art process will achieve any claimed result; such as the number percentage, the B/A ratio, the average value, etc. This reasoning applies to any claim below where a result is claimed.
Regarding claim 2, Kaga does not specifically teach:
wherein the bonding temperature is not more than 700 °C.
However, Kaga does teach the brazing temperature can be 600-900°C; 0058, 0060.
Kaga and the claims differ in that Kaga does not teach the exact same ranges as recited in the instant claims.
However, one of ordinary skill in the art at the time/before the effective filing date of the invention would have considered the invention to have been obvious because the ranges taught by Kaga overlap the instantly claimed ranges and therefore are considered to establish a prima facie case of obviousness. It would have been obvious to one of ordinary skill in the art to select any portion of the disclosed ranges including the instantly claimed ranges from the ranges disclosed in the prior art reference, particularly in view of In re Peterson 65 USPQ2d 1379 (CAFC 2003); In re Geisler 43 USPQ2d 1365 (Fed. Cir. 1997); In re Woodruff, 16 USPQ2d 1934 (CCPA 1976); In re Malagari, 182 USPQ 549, 553 (CCPA 1974), and MPEP 2144.05. This reasoning applies to any claim and limitation in this action where a range is being claimed.
Even so, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention that one would not need to heat above 700°C to bond the SA A-44Ti-Active braze since it has a melting point of 612°C.
Regarding claims 4, 7, 9-11, and 15, 16, and 20, these claims are drawn to results and thus are addressed in the rejection of claim 1.
wherein 1.1 ≤ B/A ≤ 5 is satisfied;
wherein the number percentage is not more than 1%/0%;
wherein an average value of the major diameters of the copper crystal grains in the three regions is not less than 50 μm and not more than 150 μm;
wherein a number percentage of the copper crystal grains having major diameters within an average range in the three regions is not less than 80%, and
the average range is not less than 0.5 times and not more than 2 times an average value of the major diameters of the copper crystal grains in the three regions; and
wherein an arithmetic average height Wa of a waviness curve of the ceramic substrate is not more than 2 μm, and a maximum cross-sectional height Wt of the waviness curve is not more than 10 μm.
Regarding claim 5, 12, and 17, the incorporation of the SA A-44Ti-Active braze meets these claims:
wherein a largest endothermic peak of a DSC curve of the brazing material is at not more than 700 °C; and
wherein the brazing material includes Ag, Cu, and Ti.
Regarding claim 6, Kaga teaches:
A method for manufacturing a ceramic copper circuit board [circuit board (1); figure 1], comprising:
the method for manufacturing the bonded body according to claim 1; and
a process of providing a circuit structure in the bonded copper plate [metal circuit plate (3); 0004].
Regarding claims 13 and 18, Kaga teaches:
wherein the ceramic substrate is one of a silicon nitride substrate or an aluminum nitride substrate [silicon nitride or aluminum nitride; 0081-0082], and
Kaga does not teach:
the ceramic substrate has a length of not less than 200 mm and a width of not less than 200 mm.
Yuasa teaches typically, the ceramic-copper composite (10) of the present embodiment has a substantially rectangular shape having a size of about 10 mm×10 mm to 200 mm×200 mm; 0107. Note this implies that the composite may be larger or smaller than the taught size.
While Kaga is silent as to the size of the ceramic substrate it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to perform the prior art process on any sized substrate, including that claimed, in order to manufacture a desired electronic component. Note that Yuasa overlaps the claimed range since about 200 mm x 200 mm includes the claimed endpoint of 200 mm x 200 mm.
Regarding claim 21, this claim is addressed in the rejection of claim 1:
wherein the average grain size A of the copper plate before the bonding process is not less than 10 µm and not more than 200 µm.
Response to Arguments
Applicant's arguments filed 8/7/26 have been fully considered but they are not persuasive.
The applicant lists four conditions that are required to achieve the claimed microstructure. With respect to conditions i-iii) Kaga teaches a bonding temperature of 600-900°C and with the incorporation of the SA A-44Ti-Active braze these conditions would be met as one does not need to heat to above 700°C to melt/reflow this braze. Additionally, it is known that active brazes can be supplied as elemental powders in a paste, as taught by Yuasa, and that the size of a LMP particle to that of a HMP is a result effective variable as taught by Shearer. As for condition iv) this is met by the incorporation of Yuasa grain size prior to bonding as noted in the rejection. Thus, since the prior art process meets these limitations then it is the examiner’s position that the prior art process will achieve the claimed microstructure.
In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). In the case of Yuasa, the applicant repeatably attacks Yuasa for teachings not relied upon; such as bonding temperature, endothermic peak, braze melting point, Sn/In being the largest particle, the claimed B/A ratio, etc.
The applicant argues,
“Yuasa discusses an average grain size measured by an intercept method on a "second surface" (e.g., Yuasa [0076]-[0078]). However, Yuasa does not teach "major diameter" based pre-bond grain size range (10 to 200 µm) and does not teach preparing it by "processing rate" as in the present specification.”
Note that the applicant does not claim the method in which the pre-bond grain size range is to be measured or processed. Even so, given the broad range being claimed it is reasonable to assume that the Yuasa method of measuring and that of the applicant’s will overlap.
As for any arguments drawn to the braze melting point, these are moot due to the incorporation of the SA A-44Ti-Active braze.
In response to applicant's argument that the prior art does recognize that coarse copper grains on the copper-plate surface can increase warp, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure; see PTO 892.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CARLOS J GAMINO whose telephone number is (571)270-5826. The examiner can normally be reached M-F 9-6.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Walker can be reached at 5712723458. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/CARLOS J GAMINO/Examiner, Art Unit 1735
/KEITH WALKER/Supervisory Patent Examiner, Art Unit 1735
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