DETAILED ACTION
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 and 3-4 are rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Hayashi (U.S. PGPub 2015/0270191).
Regarding claim 1, Hirano teaches a semiconductor device (Fig. 11) comprising a heat spreader (46, [0065]), a semiconductor element including a front surface electrode, the semiconductor element mounted on an upper surface of the heat spreader (12, [0067]), a metal block including a bonding surface bonded to the front surface electrode of the semiconductor element and at least one heat dissipating surface connected to the upper surface of the heat spreader with interposition of an insulating member, the metal block extending from the bonding surface to the at least one heat dissipating surface so as to straddle above at least one side of the semiconductor element (47, [0065]-[0066]; [0035] upper heat sink electrically connected to semiconductor chip 12 at upper surface; insulating member 48, [0068]), a terminal including a first end bonded to the metal block and a second end positioned on an opposite side from the first end and formed to be connectable to an external circuit (Fig. 12, [0066], 47b), and a sealing material sealing the heat spreader, the semiconductor element, the metal block, and the first end of the terminal, wherein the second end of the terminal is exposed from the sealing material (17, [0066]); wherein the semiconductor element includes a control electrode, a signal terminal bonded to the control electrode through a metal wire, wherein the sealing material seals the metal wire ([0036], control electrode connected to lead frame with bonding wire).
Hirano does not explicitly teach wherein the metal block is bonded to the semiconductor element with only an interposition of a bonding material. Hirano teaches wherein a metal element is between the metal block and semiconductor element (Fig. 11, 15, [0067]).
Hayashi teaches wherein a spacer block between a heat sink and semiconductor element may be omitted and bonded with only interposition of a bonding material (Fig. 4, 20, 50, [0023]).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Hayashi with Hirano such that the metal block is bonded to the semiconductor element with only an interposition of a bonding material for the purpose of omitting the spacer element (Hayashi, [0023]).
Regarding claim 3, the combination of Hirano and Hayashi teaches wherein the insulating member is an insulating resin film provided on the upper surface of the heat spreader (Hirano, [0072]). It would have been obvious to a person having ordinary skill in the art to further combine the teachings of Hirano and Hayashi for the reasons set forth in the rejection of claim 1.
Regarding claim 4, the combination of Hirano and Hayashi teaches wherein the at least one heat dissipating surface is a plurality of heat dissipating surfaces, the bonding surface is positioned between the plurality of heat dissipating surfaces and is bonded to the front surface electrode, and the metal block extends from the bonding surface to the plurality of heat dissipating surfaces so as to straddle above a plurality of sides of the semiconductor element (Hirano, Fig. 11). It would have been obvious to a person having ordinary skill in the art to further combine the teachings of Hirano and Hayashi for the reasons set forth in the rejection of claim 1.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Hayashi (U.S. PGPub 2015/0270191) and Fujita (U.S. PGPub 2019/0221490).
Regarding claim 2, the combination of Hirano and Hayashi does not explicitly teach wherein the metal block includes a through hole in the bonding surface.
Fujita teaches wherein a metal block includes a through hole adjacent to a coupling portion ([0063], 29, Fig. 3).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Fujita with Hirano and Hayashi such that the metal block includes a through hole in the bonding surface for the purpose of restricting peeling of the sealing material (Fujita, [0063]).
Claims 5 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Hayashi (U.S. PGPub 2015/0270191) and Koide (U.S. PGPub 2009/0079062).
Regarding claim 5, the combination of Hirano and Hayashi does not explicitly teach wherein the metal block includes a recessed portion outside a bonding portion in which the bonding surface and the front surface electrode are bonded, and the recessed portion is recessed in a direction from a lower surface of the metal block toward the upper surface with respect to the bonding surface.
Koide teaches wherein a heat spreading metal block is bonded to a semiconductor device at a bonding surface and a substrate upper surface, wherein the metal block includes a recessed portion outside a bonding portion in which the bonding surface and the front surface electrode are bonded, and the recessed portion is recessed in a direction from a lower surface of the metal block toward the upper surface with respect to the bonding surface (Fig. 1, 14, [0021]; area between center and peripheral region of 14).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Koide with Hirano and Hayashi such that the metal block includes a recessed portion outside a bonding portion in which the bonding surface and the front surface electrode are bonded, and the recessed portion is recessed in a direction from a lower surface of the metal block toward the upper surface with respect to the bonding surface for the purpose of providing thicker portions at appropriate regions for heat dissipation ([Koide, [0021]).
Regarding claim 7, the combination of Hirano and Hayashi does not explicitly teach wherein the metal block is formed of a material having a linear expansion coefficient of 7 ppm/° C. or more and 12 ppm/° C. or less.
Koide teaches wherein a heat spreading metal block is bonded to a semiconductor device at a bonding surface and a substrate upper surface, wherein the metal block includes a recessed portion outside a bonding portion in which the bonding surface and the front surface electrode and wherein the metal block is formed from a material having a linear expansion coefficient of 11 ppm/° C ([0021]). In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists. See MPEP 2144.05.
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Koide with Hirano and Hayashi such that the metal block is formed of a material having a linear expansion coefficient of 7 ppm/° C. or more and 12 ppm/° C. or less for the purpose of providing efficient heat dissipation (Koide, [0021]).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Hayashi (U.S. PGPub 2015/0270191) and Koide (U.S. PGPub 2009/0079062).
Regarding claim 6, the combination of Hirano and Hayashi does not explicitly teach wherein the metal block includes a hole penetrating between a bottom portion of the recessed portion and the upper surface of the metal block.
Fujita teaches wherein a metal block includes a through hole ([0063], 28, 29, Fig. 3).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Fujita with Hirano and Hayashi such that the metal block includes a through hole in the bonding surface for the purpose of restricting peeling of the sealing material (Fujita, [0063]).
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Hayashi (U.S. PGPub 2015/0270191) and Arai (U.S. PGPub 2015/0008570).
Regarding claim 8, the combination of Hirano and Hayashi does not explicitly teach wherein the semiconductor element is formed of SiC. Hirano teaches wherein the semiconductor element is a power semiconductor device such as an IGBT ([0034]).
Arai teaches wherein an IGBT is formed of SiC ([0005]).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Arai with Hirano and Hayashi such that the semiconductor element is SiC for the purpose of implementing the power device of Hirano (Hirano, [0034]; Arai, [0005]).
Claims 9 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Hayashi (U.S. PGPub 2015/0270191) and Kimura (U.S. PGPub 2013/0062745).
Regarding claim 9, Hirano teaches a semiconductor device (Fig. 11) comprising a heat spreader (46, [0065]), a semiconductor element including a front surface electrode, the semiconductor element mounted on an upper surface of the heat spreader (12, [0067]), a metal block including a bonding surface bonded to the front surface electrode of the semiconductor element and at least one heat dissipating surface connected to the upper surface of the heat spreader with interposition of an insulating member, the metal block extending from the bonding surface to the at least one heat dissipating surface so as to straddle above at least one side of the semiconductor element (47, [0065]-[0066]; [0035] upper heat sink electrically connected to semiconductor chip 12 at upper surface; insulating member 48, [0068]), a terminal including a first end bonded to the metal block and a second end positioned on an opposite side from the first end and formed to be connectable to an external circuit (Fig. 12, [0066], 47b), and a sealing material sealing the heat spreader, the semiconductor element, the metal block, and the first end of the terminal, wherein the second end of the terminal is exposed from the sealing material (17, [0066]); wherein the semiconductor element includes a control electrode, a signal terminal bonded to the control electrode through a metal wire, wherein the sealing material seals the metal wire ([0036], control electrode connected to lead frame with bonding wire).
Hirano does not explicitly teach wherein the metal block is bonded to the semiconductor element with only an interposition of a bonding material. Hirano teaches wherein a metal element is between the metal block and semiconductor element (Fig. 11, 15, [0067]).
Hayashi teaches wherein a spacer block between a heat sink and semiconductor element may be omitted and bonded with only interposition of a bonding material (Fig. 4, 20, 50, [0023]).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Hayashi with Hirano such that the metal block is bonded to the semiconductor element with only an interposition of a bonding material for the purpose of omitting the spacer element (Hayashi, [0023]).
Hirano does not explicitly teach wherein the insulating member is the sealing material.
Kimura teaches wherein a metal block and heat spreader are coupled by an insulating member which is the package sealing material (Fig. 14, A11, A6, A7/A75, [0200]).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Kimura with Hirano such that the insulating member is the sealing material for the purpose of reducing cost and increasing manufacturing efficiency (Kimura, [0214]).
Regarding claim 11, the combination of Hirano, Hayashi, and Kimura teaches wherein the metal block has an inclined surface or a curved surface at an end portion of the heat dissipating surface (Kimura, [00233]-[0236], Fig. 28). It would have been obvious to a person having ordinary skill in the art to further combine the teachings of Hirano, Hayashi, and Kimura for the purpose of improving manufacturability (Kimura, [0236]).
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Hayashi (U.S. PGPub 2015/0270191), Kimura (U.S. PGPub 2013/0062745) and Hirakawa (U.S. Pat. 5814878).
Regarding claim 10, the combination of Hirano, Hayashi, and Kimura does not explicitly teach wherein the metal block includes a plurality of narrow grooves in the heat dissipating surface and extending directions of the plurality of narrow grooves are unidirectionally aligned.
Hirakawa teaches wherein a heat dissipating metal block includes a plurality of unidirectionally aligned narrow grooves at the heat transfer surface (Figs. 13-14, col. 1, l. 13-57).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Hirakawa with Hirano, Hayashi, and Kimura such that the metal block includes a plurality of narrow grooves in the heat dissipating surface and extending directions of the plurality of narrow grooves are unidirectionally aligned for the purpose of enhancing contact between the metal block and the sealing material and enhancing the filling process with the sealing material (Hirakawa, col. 1, l. 42-46).
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Hayashi (U.S. PGPub 2015/0270191), Kimura (U.S. PGPub 2013/0062745) and Koide (U.S. PGPub 2009/0079062).
Regarding claim 12, the combination of Hirano, Hayashi and Kimura does not explicitly teach wherein the metal block is formed of a material having a linear expansion coefficient of 7 ppm/° C. or more and 12 ppm/° C. or less.
Koide teaches wherein a heat spreading metal block is bonded to a semiconductor device at a bonding surface and a substrate upper surface, wherein the metal block includes a recessed portion outside a bonding portion in which the bonding surface and the front surface electrode and wherein the metal block is formed from a material having a linear expansion coefficient of 11 ppm/° C ([0021]). In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists. See MPEP 2144.05.
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Koide with Hirano, Hayashi, and Kimura such that the metal block is formed of a material having a linear expansion coefficient of 7 ppm/° C. or more and 12 ppm/° C. or less for the purpose of providing efficient heat dissipation (Koide, [0021]).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Kimura (U.S. PGPub 2013/0062745), Hayashi (U.S. PGPub 2015/0270191) and Arai (U.S. PGPub 2015/0008570).
Regarding claim 13, the combination of Hirano, Hayashi, and Kimura does not explicitly teach wherein the semiconductor element is formed of SiC. Hirano teaches wherein the semiconductor element is a power semiconductor device such as an IGBT ([0034]).
Arai teaches wherein an IGBT is formed of SiC ([0005]).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Arai with Hirano, Hayashi, and Kimura such that the semiconductor element is SiC for the purpose of implementing the power device of Hirano (Hirano, [0034]; Arai, [0005]).
Claims 14-16 are rejected under 35 U.S.C. 103 as being unpatentable over Hirano (U.S. PGPub 2003/0122232) in view of Kimura (U.S. PGPub 2013/0062745), Hayashi (U.S. PGPub 2015/0270191), and Hirakawa (U.S. Pat. 5814878)
Regarding claims 14-16, Hirano teaches a method of manufacturing a semiconductor device (Fig. 11), comprising mounting a semiconductor element on an upper surface of a heat spreader (46, [0065][ 12, [0067]), and fixing a metal block so as to straddle above at least one side of the semiconductor element (47, [0065]-[0066]), and bonding a signal terminal to a control electrode of the semiconductor element through a metal wire ([0036], control electrode connected to lead frame with bonding wire);
wherein the fixing of the metal block includes: bonding a bonding surface of the metal block to a front surface electrode of the semiconductor element (Fig. 11, [0035] upper heat sink electrically connected to semiconductor chip 12 at upper surface), and connecting a heat dissipating surface of the metal block to the upper surface of the heat spreader with interposition of an insulating member (48, [0068]), and providing a sealing material for sealing the heat spreader, the semiconductor element, and the metal block (17, [0065]).
Hirano does not explicitly teach wherein the metal block is bonded to the semiconductor element with only an interposition of a bonding material. Hirano teaches wherein a metal element is between the metal block and semiconductor element (Fig. 11, 15, [0067]).
Hayashi teaches wherein a spacer block between a heat sink and semiconductor element may be omitted and bonded with only interposition of a bonding material (Fig. 4, 20, 50, [0023]).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Hayashi with Hirano such that the metal block is bonded to the semiconductor element with only an interposition of a bonding material for the purpose of omitting the spacer element (Hayashi, [0023]).
Hirano does not explicitly teach wherein the connecting of the heat dissipating surface of the metal block comprises injecting the sealing material as the insulating member into a gap between the heat dissipating surface of the metal block and the upper surface of the heat spreader, and the sealing material is injected through an injection gate provided in a lateral direction of the gap between the heat dissipating surface of the metal block and the upper surface of the heat spreader, wherein a height of the injection gate matches a height of the upper surface of the heat spreader, and wherein the metal block includes a plurality of narrow grooves in the heat dissipating surface, and extending directions of the plurality of narrow grooves are a direction from the injection gate toward the gap.
Kimura teaches wherein a metal block and heat spreader are coupled by an insulating member which is the package sealing material (Fig. 14, A11, A6, A7/A75, [0200]).
Hirakawa teaches a heat dissipating metal block (Figs. 13-14, col. 1, l. 13-57), wherein the sealing material is injected through an injection gate provided in a lateral direction of the gap adjacent to the heat dissipating surface of the metal block (Fig. 8, 33, col. 7, l. 33-65), wherein a height of the injection gate matches a height of the heat dissipating surface, the metal block includes a plurality of narrow grooves in the heat dissipating surface, and extending directions of the plurality of narrow grooves are a direction from the injection gate toward the gap (Figs. 13-14, col. 1, l. 13-57; Fig. 8).
Therefore it would have been obvious to a person having ordinary skill in the art before the time of the effective filing date to combine the teachings of Kimura and Hirakawa with Hirano such that the connecting of the heat dissipating surface of the metal block comprises injecting the sealing material as the insulating member into a gap between the heat dissipating surface of the metal block and the upper surface of the heat spreader, and the sealing material is injected through an injection gate provided in a lateral direction of the gap between the heat dissipating surface of the metal block and the upper surface of the heat spreader, wherein a height of the injection gate matches a height of the upper surface of the heat spreader, and wherein the metal block includes a plurality of narrow grooves in the heat dissipating surface, and extending directions of the plurality of narrow grooves are a direction from the injection gate toward the gap, for the purpose of for the purpose of reducing cost and increasing manufacturing efficiency (Kimura, [0214]), enhancing contact between the metal block and the sealing material, enhancing the filling process with the sealing material (Hirakawa, col. 1, l. 42-46), and preventing voids during filling (Hirakawa, col. 7, l. 54-65).
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
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/ALIA SABUR/Primary Examiner, Art Unit 2812
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