DETAILED ACTION
Election/Restrictions
A restriction requirement was mailed on 12/4/25.
Applicant’s election without traverse of Species II (Fig. 5) in the reply filed on 1/28/26 is acknowledged. Claims 4-5 and 10-11 are withdrawn.
Specification
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed.
The following title is suggested: Semiconductor device having heat sink part that promotes resin flow
Claim Objections
Claim 2 is objected to because “outer shape portion” lacks proper antecedent basis and should be changed to “an outer shape portion”.
Claim 6 is objected to because “an RC-IGBT” should be changed to “a reverse-conducting IGBT [RC-IGBT]”; the acronym appears to be a term of art for this phrase according to internet searches, which indicate that a reverse-conducting IGBT integrates a free-wheeling diode and a power device into a single chip.
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.
Claim(s) 1-3, 6-9, and 12 is/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 limitation “wherein a surface of the heat sink facing the die pad includes a flow promotion part formed to separate from a plane including the die pad in a region overlapping the die pad and not overlapping the power chip”.
The metes and bounds of the claimed limitation can not be determined for the following reasons:
First, the language “formed to separate from a plane including the die pad in a region overlapping the die pad and not overlapping the power chip” is unclear. The top surface of the heat sink 21 in Fig. 5 is not in a plane including the die pad 6, so it is unclear how the surface “is formed to separate from a plane including the die pad”.
Second, the claim is directed to a device, wherein the limitation “to separate…” is a process, so it is unclear how the surface can perform a process.
Third, it is unclear what “in a region overlapping the die pad and not overlapping the power chip” refers to, i.e. if it refers to only the “surface of the heat sink”, or to the “flow promotion part” or to the “separate from a plane” process.
Fourth, it is unclear what properties a part needs to have in order to be a “flow promotion part”, and thus it is not possible for one of ordinary skill in the art to know if they are infringing on this claimed invention. First, the claim does not specify what the “flow” refers to – if it is the resin, if it is heat, or if it is something else. It is a heat sink, so presumably any heat sink material is intended to promote flow of heat away from the power chip, so any part of a heat sink could be a “flow promotion part.” Even if this is specific to a resin flow, it is unclear what geometry, material, or other property the heat sink surface must have in order to be “flow promoting”. Applicant labels 12 in Fig. 4 as the “flow promotion part”, although it is unclear why. The drawing shows 12 having a rounded shape, but the specification recites that it may be “linear” (see para 44). Furthermore, a smooth upper surface of the heat sink provides no resistance to flow of resin thereon, as compared to a surface having a wall or other obstacle in the resin’s path, so it is unclear why that is not a “flow promotion part”. The applicant has not described any concrete criteria regarding how to judge if a part of the heat sink’s surface “promotes” flow of resin.
Claims 2-3, 6-9, and 12 depend from claim 1 and inherit its deficiencies.
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Claim 3 recites the limitation “wherein a surface of the heat sink on the die pad side includes recesses formed to separate from a plane including the die pad at positions corresponding to spaces among a plurality of the die pads”.
The metes and bounds of the claimed limitation can not be determined for the following reasons:
First, the language “formed to separate from a plane including the die pad at positions corresponding to spaces among a plurality of the die pads” is unclear. The top surface of the heat sink 21 in Fig. 5, and the recesses 22, are not in a plane including the die pad 6, so it is unclear how the surface or recesses are “formed to separate from a plane including the die pad”.
Second, the claim is directed to a device, wherein the limitation “to separate…” is a process, so it is unclear how the surface or recesses can perform a process.
Third, it is unclear what “at positions corresponding to spaces among a plurality of the die pads” refers to, i.e. if it refers to only the “surface of the heat sink”, to the recesses, or to the location of the “separat[ion]”.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102, some of which form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1 is/are rejected under 35 U.S.C. 102(a)(1) and 102(a)(2) as being anticipated by JP H08-148515 (“Shibata”) (see copy of document, including the English translation thereof, provided by the Applicant and listed on the 10/4/23 IDS).
Shibata teaches, for example:
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Shibata teaches:
1. A semiconductor apparatus (see e.g. Fig. 9) comprising:
a heat sink (“heat dissipation metal plate” 20, see e.g. para 0028);
a die pad (“die pad” 9, see e.g. para 0003) provided above and away from the heat sink;
a power chip (“semiconductor element” 1 that “generate a relatively large amount of heat, such as motor drivers, power ICs for audio amplification…”, see e.g. para 0001-0002) provided on a surface of the die pad opposite to a surface of the die pad facing the heat sink; and
mold resin (“package body” 13, see e.g. para 0023, formed in a mold 3 using an injected molding resin, see e.g. para 0002) sealing a portion of the heat sink, the die pad and the power chip,
wherein a surface of the heat sink facing the die pad includes a flow promotion part formed to separate from a plane including the die pad in a region overlapping the die pad and not overlapping the power chip (the surface of 20 is smooth, and thus lacking in obstacles for flowing resin injected in 12 in Fig. 1, and thus would be reasonably interpreted as a “flow promotion part”; furthermore, 20 has surfaces “peripheral end surfaces” 20a that are “inclined so as to widen…” see e.g. para 0027, having a geometry that allows the resin to freely flow on it to secure it to the resin, see e.g. para 0027-0033, and 20a thus would be reasonably interpreted as a “flow promotion part”; lastly, the surfaces 20a are at the periphery of the heat sink 20, just as are Applicants 12, see e.g. Figs. 4-5, and are “linear”, just as Applicant indicates that the flow promotion part can be, see e.g. para 44 of the specification of 18/480886 as published as US 2024/0355715 A1; because 21a have a shape that Applicant describes as “flow promot[ing]” and is in the same position at the periphery of the heat sink, it is reasonable to interpret 20a as “flow promotion parts”).
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 of this title, 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) 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Shibata.
Shibata teaches claim 1, and would further teaches and/or would have suggested as obvious to one of ordinary skill in the art at the time of invention: wherein
an outer shape portion of the mold resin is provided with a gate mark that differs in gloss from other portions of the mold resin or differs in height from a surface of an outer shape portion of the mold resin due to a hollow or a projection (Shibata injects resin into the cavity of mold 3 through inlet 12, see e.g. Figs. 1 and 3; the specification indicates that a “gate mark” is a residual mark due to the flow of resin through the inlet, see e.g. para 53; whether such a mark appears different “in gloss” or in height due to a “hollow or a projection”, one of ordinary skill in the art would expect that the injected resin will have such a gloss, hollow, or projection at the inlet where the resin is pushed by the injection molding supply, presumably by a piston or air), and the flow promotion part of the heat sink is provided at a position on the opposite side to a side on which the gate mark is provided (see e.g. Figs. 1, 3, 8, and 9, wherein the inlet is on one side, and the heat sink 20 has a smooth upper surface everywhere, and has inclined surfaces 20a at its periphery, so at least some portion of the top surface of 20 and/or some portion of at least one 20a would be on the opposite side to 12 where the resin is injected and where the gate mark would be formed).
Claim(s) 6-8 and 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Shibata in view of US 2019/0355718 A1 (“Nakano”).
Shibata teaches claim 1, as discussed above, but does not explicitly teach:
wherein the power chip includes an RC-IGBT (claim 6) or wherein the power chip and a diode device are formed of wide bandgap semiconductor (claims 7-8 and 12).
Nakano teaches and/or would have suggested as obvious to one of ordinary skill in the art at the time of invention, in combination with Shibata wherein the power chip includes an RC-IGBT (see e.g. para 37, 38, Figs. 3 and 18, etc.) and wherein the power chip and a diode device are formed of wide bandgap semiconductor (see e.g. “wider forbidden bandwidth than 1.1 eV of Si, such as silicon carbide, and the like”, para 32; see e.g. material 710 in Fig. 18).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to add the invention of Nakano to the invention of Shibata. The motivation to do so is that the combination produces the predictable results of using an IGBT as the power switching element, along with a freewheeling diode as a protection diode (see e.g. para 3-5, 28, etc.).
Conclusion
Conclusion / Prior Art
The prior art made of record, because it is considered pertinent to applicant's disclosure, but which is not relied upon specifically in the rejections above, is listed on the Notice of References Cited.
Conclusion / Contact Information
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Kevin Parendo who can be contacted by phone at (571) 270-5030 or by direct fax at (571) 270-6030. The examiner can normally be reached Monday-Friday from 9 am to 4 pm ET.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Billy Kraig, can be reached at (571) 272-8660. The fax number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Kevin Parendo/Primary Examiner, Art Unit 2896