WO2021085006A1 - パワー半導体装置およびパワー半導体装置の製造方法 - Google Patents

パワー半導体装置およびパワー半導体装置の製造方法 Download PDF

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WO2021085006A1
WO2021085006A1 PCT/JP2020/036784 JP2020036784W WO2021085006A1 WO 2021085006 A1 WO2021085006 A1 WO 2021085006A1 JP 2020036784 W JP2020036784 W JP 2020036784W WO 2021085006 A1 WO2021085006 A1 WO 2021085006A1
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Prior art keywords
heat radiating
power semiconductor
radiating member
semiconductor device
circuit body
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PCT/JP2020/036784
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English (en)
French (fr)
Inventor
ひろみ 島津
裕二朗 金子
英一 井出
佑輔 高木
谷江　尚史
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日立Astemo株式会社
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Priority to US17/772,943 priority Critical patent/US20220375820A1/en
Priority to DE112020004722.9T priority patent/DE112020004722T5/de
Priority to CN202080076301.6A priority patent/CN114616661A/zh
Publication of WO2021085006A1 publication Critical patent/WO2021085006A1/ja

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    • H01L23/40—Mountings or securing means for detachable cooling or heating arrangements ; fixed by friction, plugs or springs
    • H01L23/4006—Mountings or securing means for detachable cooling or heating arrangements ; fixed by friction, plugs or springs with bolts or screws
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    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/50—Assembly of semiconductor devices using processes or apparatus not provided for in a single one of the subgroups H01L21/06 - H01L21/326, e.g. sealing of a cap to a base of a container
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    • H01L25/04—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers
    • H01L25/07—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L29/00
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Definitions

  • the present invention relates to a power semiconductor device and a method for manufacturing a power semiconductor device.
  • hybrid vehicles and electric vehicles have become widespread in order to reduce the burden on the environment.
  • it is important to improve the performance of mounted parts, and power conversion devices that convert DC power to AC power are no exception, and miniaturization and cost reduction are required.
  • the heat dissipation performance of the power semiconductor device has deteriorated due to insufficient adhesion to the heat dissipation surface.
  • the power semiconductor device includes a circuit body incorporating a power semiconductor element, a first heat radiating member arranged on the first heat radiating surface side of the circuit body to dissipate heat of the circuit body, and the circuit body.
  • a fixing member arranged on the side opposite to the first heat radiating surface is provided, and the first heat radiating member and the fixing member are connected and fixed so as to be convex toward the central portion on the first heat radiating surface side.
  • the curved first heat radiating member is elastically deformed so as to be in close contact with the first heat radiating surface side.
  • a curved first heat radiating member that is convex at the center of the circuit body is arranged on the first heat radiating surface of the circuit body incorporating the power semiconductor element, and the circuit body is manufactured.
  • the first heat dissipation member is arranged on a surface opposite to the first heat dissipation surface, the first heat dissipation member is elastically deformed, and surface pressure is applied to the first heat dissipation surface of the circuit body.
  • the member and the fixing member are connected and fixed.
  • a curved first heat radiating member that is convex in the central portion on the circuit body side is arranged on the first heat radiating surface of a circuit body incorporating a power semiconductor element, and the circuit body is manufactured.
  • a curved second heat radiating member that is convex in the central portion on the circuit body side is arranged on the second heat radiating surface opposite to the first heat radiating surface, and the first heat radiating member and the second heat radiating member are elastically deformed. Then, the first heat radiation member and the second heat radiation member are connected and fixed so as to apply surface pressure to the first heat radiation surface and the second heat radiation surface of the circuit body.
  • the adhesion to the heat radiating surface is enhanced, and the heat radiating performance can be improved.
  • FIG. 1 is a cross-sectional view of the circuit body 100. This circuit body 100 is built in the power semiconductor device 200 described later.
  • the circuit body 100 is composed of a power semiconductor element 1, a bonding material 2, a first conductor 3, an insulating layer 4, and a sealing resin 10.
  • the back electrode of the power semiconductor element 1 is bonded to the first conductor 3 by the bonding material 2, and the heat conductive insulating layer 4 is connected to the surface of the first conductor 3 opposite to the surface to which the power semiconductor element 1 is connected.
  • the circuit body 100 is formed by sealing with the sealing resin 10 so that the insulating layer 4 is exposed on the surface.
  • the surface of the insulating layer 4 exposed from the sealing resin 10 serves as the heat radiating surface 4a of the circuit body 100.
  • the bonding material 2 is formed of a solder material, a sintered material, or the like.
  • the first conductor 3 is formed of, for example, copper, a copper alloy, aluminum, an aluminum alloy, or the like.
  • the insulating layer 4 conducts heat generated from the power semiconductor element 1 to the heat radiating member 7 described later, and is made of a material having high thermal conductivity and high insulation withstand voltage.
  • ceramics such as aluminum oxide (alumina), aluminum nitride, and silicon nitride, or an insulating sheet or adhesive containing these fine powders is used.
  • FIG. 2 is a cross-sectional view of the power semiconductor device 200, and shows a first step of manufacturing the power semiconductor device 200 in which necessary parts are arranged.
  • the heat conductive layer 5 is arranged on the side of the heat radiating surface 4a of the circuit body 100.
  • grease for the heat conductive layer 5, grease, a thermal interface material (TIM), or the like is used.
  • the heat radiating member 7 is arranged on the side of the heat radiating surface 4a of the circuit body 100 and outside the heat conductive layer 5.
  • the heat radiating member 7 has a curved shape so that the central portion thereof is convex toward the circuit body 100 side.
  • the heat radiating member 7 shows an example of a multi-hole pipe cooling water channel in which a plurality of tubular cooling water channel pipes 7a serving as a flow path for cooling water are provided. Holes 7b for passing through the connecting member 9, which will be described later, are provided at both ends of the heat radiating member 7.
  • the shape of the heat radiating member 7 curved so as to be convex toward the circuit body 100 side is formed by using a curved mold when processing by extrusion molding. Thereby, the heat radiating member 7 having a curved shape can be formed without increasing the number of steps and the cost. In addition, the heat radiating member 7 having a curved shape can be formed by warping by press working. Further, the cooling water channel pipe 7a is processed by extrusion molding.
  • the heat radiating member 7 is formed of a member having thermal conductivity, for example, a composite material such as Cu, Cu alloy, Cu-C, Cu-CuO, or a composite material such as Al, Al alloy, AlSiC, Al-C. There is.
  • the fixing member 8 is arranged on the side opposite to the heat radiating surface 4a of the circuit body 100.
  • the fixing member 8 has a surface parallel to the surface of the circuit body 100 opposite to the heat radiation surface 4a, and holes 8b for passing the connecting member 9 described later are provided at both ends of the fixing member 8. ing.
  • a composite material such as Cu, Cu alloy, Cu-C, Cu-CuO, a composite material such as Al, Al alloy, AlSiC, Al-C, or a metal such as stainless steel is used.
  • the connecting member 9 is a member that connects and fixes the heat radiating member 7 and the fixing member 8 at their respective ends.
  • the connecting member 9 for example, stainless steel bolts and nuts are used.
  • FIG. 3 is a cross-sectional view of the power semiconductor device 200, and shows a second step of manufacturing the power semiconductor device 200 incorporating necessary parts.
  • FIG. 3 shows a state before tightening the bolts and nuts of the connecting member 9, and the heat radiating member 7 holds a curved shape so that the central portion thereof is convex toward the circuit body 100.
  • FIG. 4 is a cross-sectional view of the power semiconductor device 200, and shows a third step of manufacturing the power semiconductor device 200.
  • the bolts and nuts of the connecting member 9 are fastened and fixed at both ends of the heat radiating member 7 and the fixing member 8 so as to sandwich the circuit body 100.
  • the heat radiating member 7 is elastically deformed, and as a result, the heat radiating member 7 is brought into close contact with the heat radiating surface 4a of the circuit body 100 via the heat conductive layer 5, and a surface pressure is applied from the heat radiating member 7 to the heat radiating surface 4a. ..
  • the heat radiating member 7 before the production of the power semiconductor device 200, the heat radiating member 7 has a shape curved so that the central portion thereof is convex toward the circuit body 100 side, and has a function of a leaf spring. Therefore, after the power semiconductor device 200 is manufactured, the heat radiating member 7 is elastically deformed by the fixing member 8 and the connecting member 9, and the heat radiating member 7 is brought into close contact with the heat radiating surface 4a of the circuit body 100 via the heat conductive layer 5. Is fixed. As a result, surface pressure can be generated in a wide range of the heat conductive layer 5, particularly in the heat radiation path in the central portion, without adding a member such as a leaf spring. As a result, the contact thermal resistance of the heat conductive layer 5 is reduced, and the heat dissipation of the power semiconductor device 200 is improved.
  • FIG. 5 (A) is a simplified cross-sectional view before fixing the heat radiating member 7
  • FIG. 5 (B) is a simplified cross-sectional view after fixing the heat radiating member 7.
  • FIG. 6 shows the surface pressure distribution of the heat radiating member 7 with respect to the heat conductive layer 5 after the heat radiating member 7 is fixed.
  • the horizontal axis of FIG. 6 is the distance from the center 5c of the heat conductive layer 5, that is, when the center 5c of the heat conductive layer 5 is zero and the end 5d of the heat conductive layer 5 is 1, the end from the center. Indicates a dimensionless value at the distance to.
  • the vertical axis of FIG. 6 shows the surface pressure applied to the heat conductive layer 5 by the heat radiating member 7.
  • FIG. 6 shows the result of simulating the surface pressure distribution of the heat conductive layer 5 by the finite element method.
  • the heat radiating member 7 has a shape in which the central portion thereof is curved so as to be convex toward the circuit body 100, and the heat radiating member 7 is shown in FIG. 5A from the state before being fixed.
  • the heat radiating member 7 shown in FIG. 5B is in the fixed state, the surface pressure distribution of the heat conductive layer 5 is as shown in FIG.
  • the surface pressure in the compression direction applied from the heat radiating member 7 to the heat conductive layer 5 is evenly applied over the entire distance.
  • the heat radiating member 7 having a curved shape so as to be convex toward the circuit body 100 is elastic so that the amount of protrusion toward the circuit body 100 side is reduced by the connecting member 9 such as a bolt and a nut. Be transformed.
  • the convex amount of the heat radiating member 7 after fixing is slightly convex toward the circuit body 100 side or has a flat shape. Then, after the heat radiating member 7 is fixed, as shown in FIG. 6, a surface pressure in the compression direction is generated on the entire surface of the heat conductive layer 5 at the interface with the heat radiating member 7.
  • the surface pressure at which the heat radiating member 7 and the heat conductive layer 5 are in close contact with each other may be set to be larger on the central portion side of the circuit body 100 than on the end portion side of the circuit body 100. Further, the heat radiating member 7 in a state where the heat radiating member 7 is elastically deformed and fixed is convex toward the circuit body 100 at the central portion of the heat radiating member 7, or flat toward the circuit body 100 on the entire surface of the heat radiating member 7. It may be set as follows.
  • FIG. 7A is a simplified cross-sectional view before fixing the heat radiating member 7'
  • FIG. 7B is a simplified cross-sectional view after fixing the heat radiating member 7'
  • FIG. 8 shows the surface pressure distribution of the heat radiating member 7'with respect to the heat conductive layer 5 after the heat radiating member 7'is fixed.
  • FIG. 8 shows the result of simulating the surface pressure distribution of the heat conductive layer 5 by the finite element method.
  • the heat radiating member 7' has a flat plate shape, and the state before the heat radiating member 7'shown in FIG. 5 (A) is changed to the state after the heat radiating member 7'shown in FIG. 5 (B) is fixed.
  • the surface pressure distribution of the heat conductive layer 5 is as shown in FIG.
  • tension is applied to the central portion of the heat conductive layer 5, and surface pressure in the compression direction is applied to both ends of the heat conductive layer 5.
  • the heat radiating member 7' when the non-curved flat heat radiating member 7'is fixed at both ends, the heat radiating member 7'is directed to the circuit body 100 side with the end of the circuit body 100 as a fulcrum. It is elastically deformed so as to be concave.
  • the surface pressure distribution generated in the heat conductive layer 5 is such that the compressed surface pressure is generated only in the vicinity of the periphery which is the fulcrum of the end of the circuit body 100, and the heat radiation member 7 is in the center. Compressed surface pressure cannot be generated near the portion.
  • the power semiconductor element 1 when the power semiconductor device 200 is in operation, the power semiconductor element 1 generates heat, the heat is thermally conducted to the bonding material 2 and the first conductor 3, and further, an insulating layer is formed.
  • the heat conduction layer 5 and the heat conduction layer 5 are heat-conducted and radiated to the heat radiating member 7. At this time, the temperature rises most in the vicinity of the power semiconductor element 1, so it is important to improve the heat dissipation in the region of the heat conductive layer 5 close to the power semiconductor element 1.
  • the compressed surface pressure of the heat conductive layer 5 does not decrease in the central portion close to the power semiconductor element 1 as compared with the end portion of the circuit body 100 far from the power semiconductor element 1 of the heat conductive layer 5.
  • the power semiconductor device 200 can obtain high heat dissipation performance.
  • the circuit body 100 is sandwiched between connecting members 9 such as bolts and nuts, and both ends of the heat radiating member 7 are sandwiched from the side opposite to the heat radiating member 7. It is necessary to apply a load to. At this time, it is desirable that the rigidity of the load-bearing portion at the end of the heat radiating member 7 is higher than the rigidity of the heat radiating portion (that is, the elastically deformed portion) which is the central portion of the heat radiating member 7.
  • the end is forcibly displaced by a connecting member 9 such as a bolt, and the heat-dissipating part is efficiently loaded when the load is applied.
  • a connecting member 9 such as a bolt
  • the heat-dissipating part is efficiently loaded when the load is applied.
  • it is desirable that the plate thickness of the load-bearing portion of the heat radiating member 7 is larger than the base thickness of the heat radiating portion provided with the cooling water channel pipe.
  • the heat radiating portion can be elastically deformed efficiently.
  • compressive stress can be generated in a wide region including the central portion of the heat conductive layer 5.
  • the contact thermal resistance of the heat conductive layer 5 is reduced, and the power semiconductor device 200 having high heat dissipation performance can be realized.
  • FIG. 9 is a cross-sectional view showing a modified example of the power semiconductor device 200.
  • the same parts as those in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted.
  • the difference is that the ceramic substrate 11 with a conductor is provided in FIG. 9 instead of the insulating layer 4 shown in FIG.
  • the first conductor layer 11b is arranged on one surface of the ceramic substrate 11a, and the second conductor layer 11c is arranged on the other surface.
  • the first conductor layer 11b of the ceramic substrate 11 with a conductor is connected to the first conductor 3 by a bonding material 12.
  • the first conductor layer 11b and the second conductor layer 11c are formed of, for example, copper, a copper alloy, aluminum, an aluminum alloy, or the like.
  • the bonding material 12 is formed of a solder material, a sintered material, or the like.
  • FIG. 10 is a cross-sectional view showing a modified example of the power semiconductor device 200.
  • the same parts as those in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted.
  • the cross-sectional shape of the cooling water channel pipe 7a of the heat radiating member 7 shown in FIG. 4 is different in this modification.
  • the cross-sectional shape of the cooling water channel pipe 7a of the heat radiating member 7 is rectangular.
  • the cross-sectional shape of the cooling water channel pipe 7a is hexagonal, and the side wall of the cooling water channel pipe 7a forms a tapered portion 7c toward the circuit body 100 side.
  • the heat radiating member 7 is substantially thin at the side portion of the rectangle facing the circuit body 100 side, so that the surface of the heat radiating member 7 is in close contact with the heat conductive layer 5. There was a risk that the pressure would weaken at the position of the cooling water channel pipe 7a.
  • the cross-sectional shape of the cooling water channel pipe 7a is not limited to hexagonal shape, but may be pentagonal or triangular, and the side wall of the cooling water channel pipe 7a forms a tapered portion 7c on the circuit body 100 side. Any shape may be used as long as the cross-sectional shape of the cooling water channel pipe 7a becomes narrower. Further, the cross-sectional shape of the cooling water channel pipe 7a may be an elliptical shape, and in this case, the tapered portion 7c of the side wall of the cooling water channel pipe 7a is curved.
  • the heat radiating member 7 can generate a uniform compressive stress on the heat conductive layer 5, the contact thermal resistance of the heat conductive layer 5 is reduced, and the power semiconductor device has high heat radiating performance. 200 can be realized.
  • FIG. 11 is a cross-sectional view showing a modified example of the heat radiating member 7.
  • the members other than the heat radiating member 7 are the same as those in FIG. 2, and the configuration of the power semiconductor device 200 after manufacturing is the same as that in FIG. In this modification, the arrangement densities of the cooling water channel pipes 7a are different.
  • the cooling water channel pipe 7a provided in the heat radiating member 7 is arranged more densely in the central portion of the heat radiating member 7, and is sparsely arranged toward the end portion of the heat radiating member 7. .. It is desirable that the rigidity of the load-bearing portion at the end of the heat radiating member 7 is higher than the rigidity of the heat radiating portion at the center of the heat radiating member 7. By making the rigidity of the load-bearing part at the end higher than the rigidity of the heat-dissipating part, the end can be forcibly displaced by a connecting member 9 such as a bolt, and the heat-dissipating part can be elastically deformed efficiently when a load is applied. It will be possible.
  • the heat radiating member 7 is elastically deformed by the fixing member 8 and the connecting member 9, and the heat radiating member 7 is closely fixed to the heat radiating surface 4a of the circuit body 100 via the heat conductive layer 5. Will be done.
  • the cross-sectional shape of the cooling water channel 7a is rectangular, but as described in the modification 2, the cross-sectional shape of the cooling water channel 7a is hexagonal, pentagonal, or triangular. It may have a structure in which a tapered portion 7c such as an ellipse is formed. Further, a cooling water channel pipe 7a having a large cross-sectional shape may be arranged toward the central portion of the heat radiating member 7, and a cooling water channel pipe 7a having a small cross-sectional shape may be arranged toward the end portion of the heat radiating member 7. Further, the heat radiating member 7 shown in the present modification may be applied to the power semiconductor device 200 provided with the ceramic substrate 11 with a conductor described in the modification 1.
  • the heat radiating portion 7 when the heat radiating member 7 is forcibly displaced by the connecting member 9 and a load is applied, the heat radiating portion is efficiently elastically deformed, and compressive stress is easily generated in the vicinity of the central portion of the heat conductive layer 5. .. Further, since the temperature of the central portion close to the power semiconductor element 1 that generates heat is the highest, heat dissipation can be improved by forming the water passages in the central portion densely.
  • FIG. 12 is a cross-sectional view of the power semiconductor device 210 according to the present embodiment and shows the first step.
  • the same parts as those of the power semiconductor device 200 shown in FIG. 2, which is the first embodiment, are designated by the same reference numerals, and the description thereof will be omitted.
  • the difference in the present embodiment is that a heat radiating member 17 is provided instead of the fixing member 8 shown in FIG.
  • the first embodiment shows an example of a power semiconductor device 200 for single-sided cooling, but the present embodiment shows an example of a power semiconductor device 210 for double-sided cooling.
  • each electrode of the power semiconductor element 1 is sandwiched between the first conductor 3 and the second conductor 13 arranged so as to face each electrode surface.
  • the power semiconductor element 1, the first conductor 3, and the second conductor 13 are joined by the joining materials 2 and 12, respectively.
  • the first conductor 3 and the second conductor 13 are formed of, for example, copper, a copper alloy, aluminum, an aluminum alloy, or the like.
  • the joining materials 2 and 12 are formed of a solder material, a sintered material, or the like.
  • the first conductor 3 is connected to the back electrode of the power semiconductor element 1, and the second conductor 13 is connected to the front electrode.
  • the second conductor 13 is formed of the same member, it may be formed by joining a plurality of members.
  • Thermally conductive insulating layers 4 and 14 are connected to the surfaces of the first conductor 3 and the second conductor 13 opposite to the surface to which the power semiconductor element 1 is connected.
  • the insulating layers 4 and 14 thermally conduct heat generated from the power semiconductor element 1 to the heat radiating members 7 and 17, and are made of a material having high thermal conductivity and high insulation withstand voltage.
  • ceramics such as aluminum oxide (alumina), aluminum nitride, and silicon nitride, or an insulating sheet or adhesive containing these fine powders can be used.
  • the circuit body 110 is formed by sealing with the sealing resin 10 so that the surfaces of the insulating layers 4 and 14 are exposed.
  • the surfaces of the insulating layers 4 and 14 exposed from the sealing resin 10 serve as the heat radiating surfaces 4a and 14a of the circuit body 110.
  • the heat conductive layers 5 and 15 are provided so as to be thermally connected to the heat radiating surfaces 4a and 14a of the circuit body 110.
  • grease, a thermal interface material (TIM) or the like can be used for the heat conductive layers 5 and 15.
  • the heat radiating members 7 and 17 are arranged on the surfaces of the heat conductive layers 5 and 15 opposite to the circuit body 110 side.
  • the heat radiating member 7 and the heat radiating member 17 are arranged so as to sandwich the circuit body 110, and the connecting member 9 for connecting and fixing the heat radiating member 7 and the heat radiating member 17 so as to sandwich the circuit body 110 at both ends thereof is arranged. ..
  • the heat radiating members 7 and 17 have a curved shape so that the central portion thereof is convex toward the circuit body 110 side.
  • the heat radiating members 7 and 17 show an example of a multi-hole pipe cooling water channel provided with a plurality of tubular cooling water channel tubes 7a and 17a serving as a flow path for cooling water. Holes 7b and 17b for passing through the connecting member 9 described later are provided at both ends of the heat radiating members 7 and 17.
  • the shape of the heat radiating members 7 and 17 curved so as to be convex toward the circuit body 110 side is formed by using a curved mold when processing by extrusion molding.
  • the heat radiating members 7 and 17 having a curved shape can be formed without increasing the number of steps and the cost.
  • the heat-dissipating members 7 and 17 having a curved shape can be formed by warping by press working.
  • the cooling water channel pipes 7a and 17a are processed by extrusion molding.
  • the heat radiating members 7 and 17 are formed from a member having thermal conductivity, for example, a composite material such as Cu, Cu alloy, Cu-C, Cu-CuO, or a composite material such as Al, Al alloy, AlSiC, Al-C, etc. Has been done.
  • the connecting member 9 is a member that connects and fixes the heat radiating member 7 and the heat radiating member 17 at their respective ends.
  • the connecting member 9 for example, stainless steel bolts and nuts are used.
  • FIG. 13 is a cross-sectional view of the power semiconductor device 210 according to the present embodiment and shows the second step.
  • the heat conductive layers 5 and 15 come into contact with the heat radiating surfaces 4a and 14a of the circuit body 110.
  • the heat radiating member 7 is in contact with the outside of the heat conductive layer 5 on the side of the heat radiating surface 4a of the circuit body 110.
  • the heat radiating member 17 is in contact with the outside of the heat conductive layer 15 on the side of the heat radiating surface 14a of the circuit body 110.
  • the connecting member 9 is passed through at each end of the heat radiating member 7 and the heat radiating member 17.
  • FIG. 13 shows a state before tightening the bolts and nuts of the connecting member 9, and the heat radiating members 7 and 17 hold a curved shape so that the central portion thereof is convex toward the circuit body 110 side.
  • the third step of the power semiconductor device 210 in this embodiment will be described.
  • the bolts and nuts of the connecting member 9 are fastened and fixed at both ends of the heat radiating member 7 and the heat radiating member 17 so as to sandwich the circuit body 110.
  • the heat radiating member 17 acts as a fixing member of the heat radiating member 7
  • the heat radiating member 7 acts as a fixing member of the heat radiating member 17.
  • the heat radiating members 7 and 17 are elastically deformed, and as a result, the heat radiating members 7 and 17 are brought into close contact with the heat radiating surfaces 4a and 14a of the circuit body 110 via the heat conductive layers 5 and 15, and the heat radiating members 7 and 17 are brought into close contact with each other.
  • Surface pressure is applied from 17 to the heat radiating surfaces 4a and 14a.
  • the surface pressure at which the heat radiating members 7 and 17 and the heat conductive layers 5 and 15 are in close contact with each other is set to be larger on the central side of the circuit body 110 than on the end side of the circuit body 110. May be good.
  • the heat radiating members 7 and 17 in a state where the heat radiating members 7 and 17 are elastically deformed and fixed are convex toward the circuit body 110 at the central portion of the heat radiating members 7 and 17, or are circuits on the entire surface of the heat radiating members 7 and 17. It may be set so as to be flat on the body 110 side. As a result, the contact thermal resistance of the heat conductive layers 5 and 15 is reduced, and a power semiconductor device 210 having high heat dissipation performance can be realized.
  • the cross-sectional shapes of the cooling water channel pipes 7a and 17a are rectangular, but as described in the second modification of the first embodiment, the cross-sectional shapes of the cooling water channel pipes 7a and 17a are , Hexagonal, pentagonal, triangular, elliptical or other tapered portions 7c may be formed.
  • the cooling water channel pipes 7a and 17a provided in the heat radiating members 7 and 17 are formed more densely in the central portion of the heat radiating members 7 and 17.
  • the heat radiating members 7 and 17 may be formed sparsely toward the ends.
  • a ceramic substrate with a conductor may be provided instead of the insulating layers 4 and 14.
  • the heat radiating members 7 and 17 having a curved shape so as to be convex toward the circuit body 110 are arranged so as to sandwich the circuit body 110, and the heat radiating member 7 is arranged.
  • fixing 17 and 17 so as to be elastically deformed it is possible to obtain a power semiconductor device 210 having high heat dissipation without adding a fixing member 8.
  • FIG. 14 is a cross-sectional view showing a modified example of the power semiconductor device 210.
  • the same parts as those in FIG. 13 are designated by the same reference numerals, and the description thereof will be omitted.
  • the configurations of the heat radiating members 7 and 17 shown in FIG. 13 are different.
  • FIG. 14 shows the second step of this modification.
  • the heat radiating members 18 and 19 have heat radiating fins 18a and 19a on their surfaces.
  • the shape of the heat radiating fins 18a and 19a may be pin fins, straight fins or corrugated fins.
  • the heat radiating members 18 and 19 are formed of electrically conductive members such as a composite material such as Cu, Cu alloy, Cu-C and Cu-CuO, or a composite material such as Al, Al alloy, AlSiC and Al-C. Has been done.
  • the heat radiating members 18 and 19 have a curved shape so that the central portion thereof is convex toward the circuit body 110 side.
  • the heat radiating member 18 is in contact with the outside of the heat conductive layer 5 on the side of the heat radiating surface 4a of the circuit body 110.
  • the heat radiating member 19 is in contact with the outside of the heat conductive layer 15 on the side of the heat radiating surface 14a of the circuit body 110.
  • the connecting member 9 is passed through at each end of the heat radiating member 18 and the heat radiating member 19.
  • FIG. 14 shows a state before tightening the bolts and nuts of the connecting member 9, and the heat radiating members 18 and 19 hold a curved shape so that the central portion thereof is convex toward the circuit body 110 side.
  • the bolts and nuts of the connecting member 9 are fastened and fixed at both ends of the heat radiating member 18 and the heat radiating member 19 so as to sandwich the circuit body 110.
  • the heat radiating members 18 and 19 are elastically deformed, and as a result, the heat radiating members 18 and 19 are brought into close contact with the heat radiating surfaces 4a and 14a of the circuit body 110 via the heat conductive layers 5 and 15, and the heat radiating members 18 and 19 are brought into close contact with each other.
  • Surface pressure is applied from 19 to the heat radiating surfaces 4a and 14a.
  • the end portion is forcibly displaced by the connecting member 9 such as a bolt, and the load is efficiently applied.
  • the central portion can be elastically deformed.
  • the plate thickness of the end portion of the heat radiating members 18 and 19 which is the load-bearing portion is set to be larger than the plate thickness of the central portion.
  • the amount of protrusion of the heat radiating members 18 and 19 after fixing is preferably slightly convex toward the circuit body 110 side or has a flat shape.
  • the heat conductive layers 5 and 15 can generate surface pressure in the compression direction in a wide region including the vicinity of the center of the heat conductive layers 5 and 15. As a result, the contact thermal resistance of the heat conductive layers 5 and 15 is reduced, and a power semiconductor device 210 having high heat dissipation performance can be obtained.
  • the outer covers of the heat radiating fins 18a and 19a of the heat radiating members 18 and 19 are not shown, but a cover may be provided to form a cooling water flow path.
  • FIG. 14 has described an example in which the heat radiating members 18 and 19 having heat radiating fins 18a and 19a are provided on both sides of the circuit body 110, but similarly to FIG. 4, heat radiating having heat radiating fins 18a on one side of the circuit body 100.
  • the configuration may be such that the member 18 is provided.
  • the sealing resin 10 includes the insulating layers 4 and 14 and the heat radiating surfaces 4a and 14a are sealed, but the first conductor 3 and the second conductor 13 are sealed. It may be sealed in the stop resin 10. If the insulating layers 4 and 14 are connected to the first conductor 3 and the second conductor 13, respectively, the same effect can be obtained.
  • the heat radiating members 7, 17, 18, 19 curved so as to be convex toward the central portion on the circuit body 100, 110 side are elastically deformed, and the heat radiating members 7, 17, 18, 19 Is acted as a leaf spring, and the heat radiating members 7, 17, 18, and 19 are pressed against the heat radiating surface at the center of the circuit bodies 100 and 110, and a surface pressure in the compression direction is generated.
  • the contact thermal resistance between the heat radiating surfaces of the circuit bodies 100 and 110 and the heat radiating members 7, 17, 18 and 19 is reduced, and the power semiconductor devices 200 and 210 having high heat radiating performance can be realized.
  • the power semiconductor device 200 includes a circuit body 100 incorporating the power semiconductor element 1, a heat radiating member 7 arranged on the heat radiating surface 4a side of the circuit body 100 to dissipate heat of the circuit body 100, and the circuit body 100.
  • a curved heat radiating member 7 is provided with a fixing member 8 arranged on the opposite side of the heat radiating surface 4a, and is convex to the central portion on the heat radiating surface 4a side by connecting and fixing the heat radiating member 7 and the fixing member 8.
  • it is elastically deformed so as to be in close contact with the heat radiating surface 4a side.
  • the adhesion to the heat radiating surface is enhanced, and the heat radiating performance can be improved.
  • a curved heat radiating member 7 having a convex shape is arranged in the central portion on the circuit body 100 side on the heat radiating surface 4a of the circuit body 100 incorporating the power semiconductor element 1.
  • the fixing member 8 is arranged on the surface of the 100 opposite to the heat radiating surface 4a, the heat radiating member 7 is elastically deformed, and the heat radiating member 7 and the fixing member 8 are applied so as to apply surface pressure to the heat radiating surface 4a of the circuit body 100. And fix the connection.
  • the adhesion to the heat radiating surface is enhanced, and the heat radiating performance can be improved.
  • a curved heat radiating member 7 having a convex shape is arranged in the central portion on the circuit body 110 side on the heat radiating surface 4a of the circuit body 110 incorporating the power semiconductor element 1, and the circuit body.
  • a curved heat-dissipating member 17 that is convex in the center of the circuit body 110 side is arranged on the heat-dissipating surface 14a on the side opposite to the heat-dissipating surface 4a of the 110, and the heat-dissipating member 7 and the heat-dissipating member 17 are elastically deformed to form the circuit body.
  • the heat radiating member 7 and the heat radiating member 17 are connected and fixed so as to apply surface pressure to the heat radiating surface 4a and the heat radiating surface 14a of 110. As a result, the adhesion to the heat radiating surface is enhanced, and the heat radiating performance can be improved.
  • the present invention is not limited to the above-described embodiment, and other embodiments that can be considered within the scope of the technical idea of the present invention are also included within the scope of the present invention as long as the features of the present invention are not impaired. .. Further, the configuration may be a combination of the above-described embodiment and a plurality of modified examples.

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  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • Power Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Thermal Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
  • Cooling Or The Like Of Electrical Apparatus (AREA)

Abstract

パワー半導体装置の放熱面に対する密着が十分ではなく、放熱性能が低下していた点が課題である。熱伝導層５を、回路体１００の放熱面４ａに当接し、放熱部材７を、回路体１００の放熱面４ａの側であって、熱伝導層５の外側に当接する。固定部材８を、回路体１００の放熱面４ａとは反対側に当接する。そして、接続部材９を、放熱部材７と固定部材８のそれぞれの端部において貫通させる。図３は、接続部材９のボルトとナットを締める前の状態を示しており、放熱部材７はその中央部が回路体１００側に凸となるように湾曲した形状を保持している。回路体１００を挟むように、放熱部材７と固定部材８の両端において、接続部材９のボルトとナットを締結して固定する。放熱部材７は弾性変形されて、回路体１００の放熱面４ａに熱伝導層５を介して放熱部材７が密着され、放熱部材７から放熱面４ａへ面圧が加わる。

Description

パワー半導体装置およびパワー半導体装置の製造方法
　本発明は、パワー半導体装置およびパワー半導体装置の製造方法に関する。
　近年、環境への負荷低減のため、ハイブリッド自動車や電気自動車が普及している。ハイブリッド自動車や電気自動車においては搭載される部品の性能向上が重要視され、直流電力を交流電力に変換する電力変換装置も例外ではなく、小型化や低コスト化が求められている。
　電力変換装置を構成する電子部品の中で発熱量が大きいパワー半導体装置を小型化するためには、冷却性能を向上させる必要がある。特許文献１では、パワー半導体装置の外周部に加える締結固定力によって、パワー半導体装置の放熱面をケース冷却面に密着させて金属ケースに固定している。
特開２０１７－２１２４０１号公報
　従来では、パワー半導体装置の放熱面に対する密着が十分ではなく、放熱性能が低下していた。
　本発明によるパワー半導体装置は、パワー半導体素子を内蔵した回路体と、前記回路体の第１放熱面側に配置されて前記回路体の熱を放熱する第１放熱部材と、前記回路体の前記第１放熱面とは反対側に配置された固定部材と、を備え、前記第１放熱部材と前記固定部材とが接続固定されることにより、前記第１放熱面側の中央部に凸となる湾曲した前記第１放熱部材が、前記第１放熱面側に密着するように弾性変形されている。
　本発明によるパワー半導体装置の製造方法は、パワー半導体素子を内蔵した回路体の第１放熱面に、前記回路体側の中央部に凸となる湾曲した第１放熱部材を配置し、前記回路体の前記第１放熱面とは反対側の面に固定部材を配置し、前記第１放熱部材を弾性変形させて、前記回路体の前記第１放熱面に面圧を加えるように、前記第１放熱部材と前記固定部材とを接続固定する。
　本発明によるパワー半導体装置の製造方法は、パワー半導体素子を内蔵した回路体の第１放熱面に、前記回路体側の中央部に凸となる湾曲した第１放熱部材を配置し、前記回路体の前記第１放熱面とは反対側の第２放熱面に、前記回路体側の中央部に凸となる湾曲した第２放熱部材を配置し、前記第１放熱部材および前記第２放熱部材を弾性変形させて、前記回路体の前記第１放熱面および前記第２放熱面に面圧を加えるように、前記第１放熱部材と前記第２放熱部材とを接続固定する。
　本発明によれば、放熱面に対する密着が高まり、放熱性能の向上を計ることができる。
回路体の断面図である。 パワー半導体装置の断面図であり、第１工程を示す。 パワー半導体装置の断面図であり、第２工程を示す。 パワー半導体装置の断面図であり、第３工程を示す。 （Ａ）（Ｂ）放熱部材の固定前、固定後の簡略断面図である。 熱伝導層の面圧分布である。 （Ａ）（Ｂ）比較例における放熱部材の固定前、固定後の簡略断面図である。 比較例における熱伝導層の面圧分布である。 パワー半導体装置の変形例１を示す断面図である。 パワー半導体装置の変形例２を示す断面図である。 放熱部材の変形例３を示す断面図である。 第２の実施形態におけるパワー半導体装置の断面図であり、第１工程を示す。 第２の実施形態におけるパワー半導体装置の断面図であり、第２工程を示す。 パワー半導体装置の変形例４を示す断面図である。
　以下、図面を参照して本発明の実施形態を説明する。以下の記載および図面は、本発明を説明するための例示であって、説明の明確化のため、適宜、省略および簡略化がなされている。本発明は、他の種々の形態でも実施する事が可能である。特に限定しない限り、各構成要素は単数でも複数でも構わない。
　図面において示す各構成要素の位置、大きさ、形状、範囲などは、発明の理解を容易にするため、実際の位置、大きさ、形状、範囲などを表していない場合がある。このため、本発明は、必ずしも、図面に開示された位置、大きさ、形状、範囲などに限定されない。
［第１の実施形態]
　図１は、回路体１００の断面図である。この回路体１００は、後述のパワー半導体装置２００に内蔵される。
　図１に示すように、回路体１００は、パワー半導体素子１、接合材２、第１の導体３、絶縁層４、封止樹脂１０より構成さる。パワー半導体素子１の裏面電極を接合材２により第１の導体３に接合し、第１の導体３のパワー半導体素子1を接続した面とは反対の面に熱伝導性の絶縁層４を接続する。そして、絶縁層４が表面に露出するように封止樹脂１０で封止することにより回路体１００が形成される。封止樹脂１０から露出している絶縁層４の表面が回路体１００の放熱面４ａとなる。
　接合材２は、はんだ材、焼結材などにより形成されている。第１の導体３は、例えば、銅、銅合金、あるいはアルミニウム、アルミニウム合金などにより形成されている。
　絶縁層４は、パワー半導体素子１から発生する熱を後述の放熱部材７に熱伝導するものであり、熱伝導率が高く、かつ、絶縁耐圧が大きい材料で形成されている。例えば、酸化アルミニウム（アルミナ）、窒化アルミニウム、窒化ケイ素等のセラミックス、あるいは、これらの微粉末を含有する絶縁シートまたは接着剤を用いる。
　図２は、パワー半導体装置２００の断面図であり、必要な部品を配置したパワー半導体装置２００を製造する第１工程を示す。
　図２に示すように、熱伝導層５を、回路体１００の放熱面４ａの側に配置する。熱伝導層５は、グリース、サーマルインターフェースマテリアル（ＴＩＭ）などを用いる。
　さらに、放熱部材７を、回路体１００の放熱面４ａの側であって、熱伝導層５の外側に配置する。放熱部材７はその中央部が回路体１００側に凸となるように湾曲した形状を有している。放熱部材７は、冷却水の流路となる管状の冷却水路管７ａが複数設けられている多穴管冷却水路の例を示している。放熱部材７の両端部には、後述の接続部材９を貫通させるための穴７ｂが設けられている。
　回路体１００側に凸となるように湾曲した放熱部材７の形状は、押出成形により加工する場合、湾曲形状の金型を用いて形成する。これにより、工程数やコストを増加させることなく、湾曲形状の放熱部材７を形成することができる。その他、プレス加工により、反りつけを行うことにより、湾曲形状の放熱部材７とすることもできる。また冷却水路管７ａは押出成形により加工される。放熱部材７は、熱伝導性を有する部材、例えばＣｕ、Ｃｕ合金、Ｃｕ－Ｃ、Ｃｕ－ＣｕＯなどの複合材、あるいはＡｌ、Ａｌ合金、ＡｌＳｉＣ、Ａｌ－Ｃなどの複合材などから形成されている。
　固定部材８を、回路体１００の放熱面４ａとは反対側に配置する。固定部材８は、回路体１００の放熱面４ａとは反対側の面と平行な面を有し、固定部材８の両端部には、後述の接続部材９を貫通させるための穴８ｂが設けられている。固定部材８は、例えばＣｕ、Ｃｕ合金、Ｃｕ－Ｃ、Ｃｕ－ＣｕＯなどの複合材、あるいはＡｌ、Ａｌ合金、ＡｌＳｉＣ、Ａｌ－Ｃなどの複合材、ステンレス鋼などの金属を使用する。
　接続部材９は、後述するように、放熱部材７と固定部材８とのそれぞれの端部において接続固定する部材である。接続部材９は、例えばステンレス鋼製のボルトとナットを使用する。
　図３は、パワー半導体装置２００の断面図であり、必要な部品を組み込んだパワー半導体装置２００を製造する第２工程を示す。
　図３に示すように、熱伝導層５を、回路体１００の放熱面４ａに当接する。さらに、放熱部材７を、回路体１００の放熱面４ａの側であって、熱伝導層５の外側に当接する。固定部材８を、回路体１００の放熱面４ａとは反対側に当接する。そして、接続部材９を、放熱部材７と固定部材８のそれぞれの端部において貫通させる。図３は、接続部材９のボルトとナットを締める前の状態を示しており、放熱部材７はその中央部が回路体１００側に凸となるように湾曲した形状を保持している。
　図４は、パワー半導体装置２００の断面図であり、パワー半導体装置２００を製造する第３工程を示す。
　図４に示すように、回路体１００を挟むように放熱部材７と固定部材８の両端において、接続部材９のボルトとナットを締結して固定する。この際に、放熱部材７は弾性変形されて、その結果、回路体１００の放熱面４ａに熱伝導層５を介して放熱部材７が密着され、放熱部材７から放熱面４ａへ面圧が加わる。
　本実施形態においては、パワー半導体装置２００の製造前において、放熱部材７はその中央部が回路体１００側に凸となるように湾曲した形状を有しており、板バネの機能を有する。このため、パワー半導体装置２００の製造後において、固定部材８および接続部材９によって、放熱部材７が弾性変形されて、回路体１００の放熱面４ａに熱伝導層５を介して放熱部材７が密着して固定される。これにより、板バネなどの部材を追加することなく、熱伝導層５の広い範囲、特に中央部の放熱経路に面圧を発生させることができる。その結果、熱伝導層５の接触熱抵抗が低減し、パワー半導体装置２００の放熱性が向上する。
　図５（Ａ）は、放熱部材７の固定前の簡略断面図、図５（Ｂ）は、放熱部材７の固定後の簡略断面図である。図６は、放熱部材７を固定した後の放熱部材７の熱伝導層５に対する面圧分布である。図６の横軸は、熱伝導層５の中央５ｃからの距離、すなわち、熱伝導層５の中央５ｃをゼロとし、熱伝導層５の端部５ｄを１とした場合に、中央から端部までの距離で無次元化した値を示す。図６の縦軸は放熱部材７が熱伝導層５に加わる面圧を示す。この図６は、熱伝導層５の面圧分布を有限要素法によりシミュレーションした結果を示す。
　本実施形態によれば、放熱部材７はその中央部が回路体１００側に凸となるように湾曲した形状を有しており、図５（Ａ）に示す放熱部材７の固定前の状態から、図５（Ｂ）に示す放熱部材７の固定後の状態にした場合、熱伝導層５の面圧分布は図６に示すようになる。図６のグラフＰに示すように、放熱部材７から熱伝導層５に加わる圧縮方向の面圧が全ての距離に亘って均等に加わる。
　すなわち、回路体１００側に凸となるように湾曲した形状をした放熱部材７は、ボルトとナットなどの接続部材９により、放熱部材７は回路体１００側への凸量が小さくなるように弾性変形される。この時、固定後の放熱部材７の凸量は、回路体１００側への少し凸となっているか、平坦形状となっていることが好ましい。そして、放熱部材７の固定後は、図６に示すように、熱伝導層５には放熱部材７との界面に全面的に圧縮方向の面圧が発生する。なお、放熱部材７と熱伝導層５とが密着する面圧は、回路体１００の端部側に比べて、回路体１００の中央部側の方が大きくなるように設定してもよい。さらに、放熱部材７を弾性変形させて固定した状態における放熱部材７は、放熱部材７の中央部において回路体１００側に凸状、または放熱部材７の全面において回路体１００側に平坦状になるように設定してもよい。
　本実施形態と比較のため、湾曲していない放熱部材７’を用いた場合の比較例を、図７（Ａ）、図７（Ｂ）、図８に示す。
　図７（Ａ）は、放熱部材７’の固定前の簡略断面図、図７（Ｂ）は、放熱部材７’の固定後の簡略断面図である。図８は、放熱部材７’を固定した後の放熱部材７’の熱伝導層５に対する面圧分布である。この図８は、熱伝導層５の面圧分布を有限要素法によりシミュレーションした結果を示す。
　放熱部材７’は平板な形状を有しており、図５（Ａ）に示す放熱部材７’の固定前の状態から、図５（Ｂ）に示す放熱部材７’の固定後の状態にした場合、熱伝導層５の面圧分布は図８に示すようになる。図８のグラフＱに示すように、熱伝導層５の中央部には引張が、熱伝導層５の両端部には圧縮方向の面圧が加わる。
　すなわち、図８に示すように、湾曲していない平板な形状の放熱部材７’を両端で固定した場合、放熱部材７’は、回路体１００の端部を支点として、回路体１００側への凹となるように弾性変形される。この場合、熱伝導層５に発生する面圧分布は、図８に示すように、回路体１００の端部の支点となっている周辺付近にのみ圧縮面圧が発生し、放熱部材７の中央部付近には圧縮面圧を発生させることができない。
　図４に示す本実施形態によるパワー半導体装置２００では、パワー半導体装置２００の動作時には、パワー半導体素子１が発熱し、その熱が接合材２と第１の導体３に熱伝導し、さらに絶縁層４と熱伝導層５を熱伝導し、放熱部材７に放熱される。この時温度が最も上昇するのは、パワー半導体素子１の周辺であるので、熱伝導層５のパワー半導体素子１に近い領域での放熱性を向上することが重要である。すなわち、熱伝導層５のパワー半導体素子１に遠い回路体１００の端部に比べて、パワー半導体素子１に近い中央部において、熱伝導層５の圧縮面圧が低下しないので、本実施形態によるパワー半導体装置２００は高い放熱性能が得られる。
　図４に示すように、放熱部材７を弾性変形させて固定するためには、例えばボルト、ナットなどの接続部材９で回路体１００を挟んで放熱部材７とは反対側から放熱部材７の両端に荷重を加える必要がある。この時、放熱部材７の端部の荷重負荷部の剛性は、放熱部材７の中央部である放熱部（すなわち弾性変形部）の剛性に比べ高いことが望ましい。端部の荷重負荷部の剛性を放熱部（すなわち弾性変形部）の剛性よりも高くすることにより、端部をボルトなどの接続部材９で強制変位を与え、荷重負荷する際、効率よく放熱部を弾性変形させることが可能となる。例えば、放熱部材７の荷重負荷部の板厚は、冷却水路管が設けられている放熱部のベース厚に比べて大きくすることが望ましい。これにより、放熱部材７を接続部材９で強制変位を与え、荷重負荷する際、効率よく放熱部を弾性変形させることが可能となる。そして、熱伝導層５の中央部を含めた広い領域に圧縮応力を発生させることができる。その結果、熱伝導層５の接触熱抵抗が低減し、放熱性能の高いパワー半導体装置２００が実現できる。
（変形例１）
　図９は、パワー半導体装置２００の変形例を示す断面図である。図４と同一の個所には同一の符号を付してその説明を省略する。図４に示す絶縁層４に替えて、図９では導体付きセラミック基板１１を設けた点が相違する。
　図９に示すように、導体付きセラミック基板１１は、セラミック基板１１ａの一面に第1導体層１１ｂが配置され、他面に第２導体層１１ｃが配置されている。導体付きセラミック基板１１の第１導体層１１ｂは第１の導体３に接合材１２により接続される。
　第１導体層１１ｂおよび第２導体層１１ｃは、例えば、銅、銅合金、あるいはアルミニウム、アルミニウム合金などにより形成されている。接合材１２ははんだ材、焼結材などにより形成されている。導体付きセラミック基板１１を使用することにより、高耐圧かつ高放熱のパワー半導体装置２００が提供される。
（変形例２）
　図１０は、パワー半導体装置２００の変形例を示す断面図である。図４と同一の個所には同一の符号を付してその説明を省略する。図４に示す放熱部材７の冷却水路管７ａの断面形状が本変形例で相違する。
　第１の実施形態では、放熱部材７の冷却水路管７ａの断面形状が長方形である場合を示した。本変形例では、図１０に示すように冷却水路管７ａの断面形状が６角形であり、回路体１００側に向けて冷却水路管７ａの側壁はテーパ部７ｃを形成している。冷却水路管７ａの側壁にテーパ部７ｃを形成したことにより、熱伝導層５に密着する放熱部材７の面圧をより均等にすることができる。冷却水路管７ａの断面形状が長方形である場合は、回路体１００側と対向する長方形の辺部分において、放熱部材７が実質的に薄くなるため、熱伝導層５に密着する放熱部材７の面圧が冷却水路管７ａの位置で弱くなる虞があった。
なお、冷却水路管７ａの断面形状は、６角形に限らず、５角形、３角形などであってもよく、冷却水路管７ａの側壁がテーパ部７ｃを形成しており、回路体１００側に向けて冷却水路管７ａの断面形状が細くなる形状であればよい。さらに、冷却水路管７ａの断面形状は、楕円形状であってもよく、この場合、冷却水路管７ａの側壁のテーパ部７ｃは曲線となる。
　本変形例のパワー半導体装置２００では、放熱部材７により熱伝導層５へ一様な圧縮応力を発生させることができ、熱伝導層５の接触熱抵抗が低減し、放熱性能の高いパワー半導体装置２００が実現できる。
（変形例３）
　図１１は、放熱部材７の変形例を示す断面図である。放熱部材７以外の部材は図２と同様であり、製造後のパワー半導体装置２００の構成は図４と同様である。本変形例では冷却水路管７ａの配置密度が相違する。
　図１１に示すように、放熱部材７に設けられている冷却水路管７ａは、放熱部材７の中央部の方が密に配置され、放熱部材７の端部に行くにしたがって疎に配置される。放熱部材７の端部の荷重負荷部の剛性は、放熱部材７の中央部である放熱部の剛性に比べ高いことが望ましい。端部の荷重負荷部の剛性を放熱部の剛性よりも高くすることにより、端部をボルトなどの接続部材９で強制変位を与え、荷重負荷する際、効率よく放熱部を弾性変形させることが可能となる。
　パワー半導体装置２００の製造後において、固定部材８および接続部材９によって、放熱部材７が弾性変形されて、回路体１００の放熱面４ａに熱伝導層５を介して放熱部材７が密着して固定される。
　なお、本変形例では冷却水路管７ａの断面形状は、長方形の例を示したが、変形例２で述べたように、冷却水路管７ａの断面形状は、６角形、５角形、３角形、楕円などテーパ部７ｃを形成した構成であってもよい。さらに、放熱部材７の中央部の方に大きな断面形状の冷却水路管７ａを配置し、放熱部材７の端部に行くにしたがって小さな断面形状の冷却水路管７ａを配置してもよい。また、本変形例で示した放熱部材７を、変形例１で述べた導体付きセラミック基板１１を設けたパワー半導体装置２００に適用してもよい。
　本変形例によれば、放熱部材７を接続部材９で強制変位を与え、荷重負荷する際、効率よく放熱部を弾性変形させ、熱伝導層５の中央部付近に圧縮応力を発生させやすくなる。
また、発熱するパワー半導体素子１に近い中央部の温度が最も高くなるため、この中央部の水路を密に形成することにより、放熱性を向上できる。
［第２の実施形態]
　図１２は、本実施形態におけるパワー半導体装置２１０の断面図であり、第１工程を示す。第１の実施形態である図２に示すパワー半導体装置２００と同一の個所には同一の符号を付してその説明を省略する。本実施形態では、図２に示す固定部材８に替えて、放熱部材１７を設けた点が相違する。第１の実施形態は、片面冷却のパワー半導体装置２００の例を示したが、本実施形態は、両面冷却のパワー半導体装置２１０の例を示す。
　図１２に示すように、パワー半導体素子１の各電極はそれぞれの電極面に対向して配置される第１の導体３、第２の導体１３によって挟まれる。パワー半導体素子１と第１の導体３、第２の導体１３とはそれぞれ接合材２、１２によって接合される。第１の導体３、第２の導体１３は、例えば、銅、銅合金、あるいはアルミニウム、アルミニウム合金などにより形成されている。接合材２、１２ははんだ材、焼結材などにより形成されている。
第１の導体３はパワー半導体素子１の裏面電極に接続され、第２の導体１３が表面電極に接続されている。第２の導体１３は同一部材で形成されている例を示したが、複数の部材を接合して形成されていてもよい。
　第１の導体３および第２の導体１３の、パワー半導体素子１が接続されている面とは反対の面には、熱伝導性の絶縁層４、１４が接続されている。絶縁層４、１４は、パワー半導体素子１から発生する熱を放熱部材７、１７に熱伝導するものであり、熱伝導率が高く、かつ、絶縁耐圧が大きい材料で形成されている。例えば、酸化アルミニウム（アルミナ）、窒化アルミニウム、窒化ケイ素等のセラミックス、あるいは、これらの微粉末を含有する絶縁シートまたは接着剤を用いることができる。
　絶縁層４、１４の表面が露出するように封止樹脂１０で封止されることにより回路体１１０が形成される。封止樹脂１０から露出している絶縁層４、１４の表面が回路体１１０の放熱面４ａ、１４ａとなる。
　回路体１１０の放熱面４ａ、１４ａに熱的に接続するように熱伝導層５、１５が設けられている。熱伝導層５、１５は、グリース、サーマルインターフェースマテリアル（ＴＩＭ）などを用いることができる。熱伝導層５、１５の回路体１１０側と反対側の面には、放熱部材７、１７が配置される。回路体１１０を挟むように放熱部材7および放熱部材１７が配置され、放熱部材7と放熱部材１７とを、その両端部で回路体１１０を挟むように、接続固定する接続部材９が配置される。
　放熱部材７、１７はその中央部が回路体１１０側に凸となるように湾曲した形状を有している。放熱部材７、１７は、冷却水の流路となる管状の冷却水路管７ａ、１７ａが複数設けられている多穴管冷却水路の例を示している。放熱部材７、１７の両端部には、後述の接続部材９を貫通させるための穴７ｂ、１７ｂが設けられている。
　回路体１１０側に凸となるように湾曲した放熱部材７、１７の形状は、押出成形により加工する場合、湾曲形状の金型を用いて形成する。これにより、工程数やコストを増加させることなく、湾曲形状の放熱部材７、１７を形成することができる。その他、プレス加工により、反りつけを行うことにより、湾曲形状の放熱部材７、１７とすることもできる。また冷却水路管７ａ、１７ａは押出成形により加工される。放熱部材７、１７は、熱伝導性を有する部材、例えばＣｕ、Ｃｕ合金、Ｃｕ－Ｃ、Ｃｕ－ＣｕＯなどの複合材、あるいはＡｌ、Ａｌ合金、ＡｌＳｉＣ、Ａｌ－Ｃなどの複合材などから形成されている。
　接続部材９は、後述するように、放熱部材７と放熱部材１７とのそれぞれの端部において接続固定する部材である。接続部材９は、例えばステンレス鋼製のボルトとナットを使用する。
　図１３は、本実施形態におけるパワー半導体装置２１０の断面図であり、第２工程を示す。
　図１３に示すように、熱伝導層５、１５を、回路体１１０の放熱面４ａ、１４ａに当接する。さらに、放熱部材７を、回路体１１０の放熱面４ａの側であって、熱伝導層５の外側に当接する。放熱部材１７を、回路体１１０の放熱面１４ａの側であって、熱伝導層１５の外側に当接する。そして、接続部材９を、放熱部材７と放熱部材１７のそれぞれの端部において貫通させる。図１３は、接続部材９のボルトとナットを締める前の状態を示しており、放熱部材７、１７はその中央部が回路体１１０側に凸となるように湾曲した形状を保持している。
　次に、本実施形態におけるパワー半導体装置２１０の第３工程を説明する。
　図１３に示す状態において、回路体１１０を挟むように放熱部材７と放熱部材１７の両端において、接続部材９のボルトとナットを締結して固定する。このとき、放熱部材１７は放熱部材７の固定部材として、放熱部材７は放熱部材１７の固定部材として、それぞれ作用する。この際に、放熱部材７、１７は弾性変形されて、その結果、回路体１１０の放熱面４ａ、１４ａに熱伝導層５、１５を介して放熱部材７、１７が密着され、放熱部材７、１７から放熱面４ａ、１４ａへ面圧が加わる。
　回路体１１０側に、凸となるように湾曲した形状を有していた放熱部材７、１７は、接続部材９の締結により、放熱部材７、１７は回路体１１０側への凸量が小さくなるように弾性変形される。この時、固定後の放熱部材７、１７の凸量は、回路体１１０側への少し凸となっているか、平坦形状となっていることが好ましい。これにより、熱伝導層５、１５には、熱伝導層５、１５の中央付近を含めた広い領域に圧縮方向の面圧を発生させることができる。なお、放熱部材７、１７と熱伝導層５、１５とが密着する面圧は、回路体１１０の端部側に比べて、回路体１１０の中央部側の方が大きくなるように設定してもよい。さらに、放熱部材７、１７を弾性変形させて固定した状態における放熱部材７、１７は、放熱部材７、１７の中央部において回路体１１０側に凸状、または放熱部材７、１７の全面において回路体１１０側に平坦状になるように設定してもよい。その結果、熱伝導層５、１５の接触熱抵抗が低減し、放熱性能の高いパワー半導体装置２１０が実現できる。
　なお、本実施形態では冷却水路管７ａ、１７ａの断面形状は、長方形の例を示したが、第１の実施形態の変形例２で述べたように、冷却水路管７ａ、１７ａの断面形状は、６角形、５角形、３角形、楕円などテーパ部７ｃを形成した構成であってもよい。さらに、第１の実施形態の変形例３で述べたように、放熱部材７、１７に設けられている冷却水路管７ａ、１７ａは、放熱部材７、１７の中央部の方が密に形成され、放熱部材７、１７の端部に行くにしたがって疎に形成してもよい。さらに、第１の実施形態の変形例１で述べたように、絶縁層４、１４に替えて、導体付きセラミック基板を設けてもよい。
　本実施形態によれば、回路体１１０を両面冷却する場合、回路体１１０側に凸となるように湾曲した形状をした放熱部材７、１７を回路体１１０を挟むように配置し、放熱部材７、１７が弾性変形するように固定することにより、固定部材８を追加することなく、放熱性の高いパワー半導体装置２１０を得ることができる。
（変形例４）
　図１４は、パワー半導体装置２１０の変形例を示す断面図である。図１３と同一の個所には同一の符号を付してその説明を省略する。図１３に示す放熱部材７、１７の構成が相違する。
　図１４は、本変形例の第２工程を示す。図１４に示すように、放熱部材１８、１９は表面に放熱フィン１８ａ、１９ａを有する。放熱フィン１８ａ、１９ａの形状はピンフィン、ストレートフィンやコルゲートフィンであっても良い。
　放熱部材１８、１９は、電気伝導性を有する部材、例えばＣｕ、Ｃｕ合金、Ｃｕ－Ｃ、Ｃｕ－ＣｕＯなどの複合材、あるいはＡｌ、Ａｌ合金、ＡｌＳｉＣ、Ａｌ－Ｃなどの複合材などから形成されている。
　放熱部材１８、１９は、その中央部が回路体１１０側に凸となるように湾曲した形状をしている。放熱部材１８を、回路体１１０の放熱面４ａの側であって、熱伝導層５の外側に当接する。放熱部材１９を、回路体１１０の放熱面１４ａの側であって、熱伝導層１５の外側に当接する。そして、接続部材９を、放熱部材１８と放熱部材１９のそれぞれの端部において貫通させる。図１４は、接続部材９のボルトとナットを締める前の状態を示しており、放熱部材１８、１９はその中央部が回路体１１０側に凸となるように湾曲した形状を保持している。
　第３工程では、図１４に示す状態において、回路体１１０を挟むように放熱部材１８と放熱部材１９の両端において、接続部材９のボルトとナットを締結して固定する。この際に、放熱部材１８、１９は弾性変形されて、その結果、回路体１１０の放熱面４ａ、１４ａに熱伝導層５、１５を介して放熱部材１８、１９が密着され、放熱部材１８、１９から放熱面４ａ、１４ａへ面圧が加わる。放熱部材１８、１９は、その端部の荷重負荷部の剛性を中央部の剛性よりも高くすることにより、端部をボルトなどの接続部材９で強制変位を与え、荷重負荷する際、効率よく中央部を弾性変形させることが可能となる。図１４に示すように、放熱部材１８、１９の荷重負荷部である端部の板厚は、中央部の板厚に比べて大きく設定されている。固定後の放熱部材１８、１９の凸量は、回路体１１０側への少し凸となっているか、平坦形状となっていることが好ましい。これにより、熱伝導層５、１５には、熱伝導層５、１５の中央付近を含めた広い領域に圧縮方向の面圧を発生させることができる。その結果、熱伝導層５、１５の接触熱抵抗が低減し、放熱性能の高いパワー半導体装置２１０を得ることができる。
　図１４では、放熱部材１８、１９の放熱フィン１８ａ、１９ａの外側のカバーを図示省略しているが、カバーを設けて冷却水の流路を形成することもできる。
　図１４では、回路体１１０を挟む両面に放熱フィン１８ａ、１９ａを有する放熱部材１８、１９を設けた例で説明したが、図４と同様に、回路体１００の片面に放熱フィン１８ａを有する放熱部材１８を設けた構成にしてもよい。
　上述した各実施形態では、封止樹脂１０が絶縁層４、１４を含み、放熱面４ａ、１４ａ以外が封止された例を示したが、第１の導体３、第２の導体１３まで封止樹脂１０に封止されていてもよい。絶縁層４、１４は、第１の導体３、第２の導体１３に、それぞれ接続されていれば、同様の効果が得られる。
　さらに、上述した各実施形態では、パワー半導体素子１が一つの場合について説明したが、パワー半導体素子１を複数個内蔵したパワー半導体装置２００、２１０にも同様に適用することができる。
　以上説明した実施形態によれば、回路体１００、１１０側の中央部に凸となるように湾曲した放熱部材７、１７、１８、１９を弾性変形して、放熱部材７、１７、１８、１９を板バネとして作用させ、放熱部材７、１７、１８、１９が回路体１００、１１０の中央部の放熱面に押し付けられ、圧縮方向の面圧が発生する。それにより、回路体１００、１１０の放熱面と放熱部材７、１７、１８、１９の接触熱抵抗が低減し、放熱性能の高いパワー半導体装置２００、２１０が実現できる。
　以上説明した実施形態によれば、次の作用効果が得られる。
（１）パワー半導体装置２００は、パワー半導体素子１を内蔵した回路体１００と、回路体１００の放熱面４ａ側に配置されて回路体１００の熱を放熱する放熱部材７と、回路体１００の放熱面４ａとは反対側に配置された固定部材８とを備え、放熱部材７と固定部材８とが接続固定されることにより、放熱面４ａ側の中央部に凸となる湾曲した放熱部材７が、放熱面４ａ側に密着するように弾性変形されている。これにより、放熱面に対する密着が高まり、放熱性能の向上を計ることができる。
（２）パワー半導体装置２００の製造方法は、パワー半導体素子１を内蔵した回路体１００の放熱面４ａに、回路体１００側の中央部に凸となる湾曲した放熱部材７を配置し、回路体１００の放熱面４ａとは反対側の面に固定部材８を配置し、放熱部材７を弾性変形させて、回路体１００の放熱面４ａに面圧を加えるように、放熱部材７と固定部材８とを接続固定する。これにより、放熱面に対する密着が高まり、放熱性能の向上を計ることができる。
（３）パワー半導体装置２１０の製造方法は、パワー半導体素子１を内蔵した回路体１１０の放熱面４ａに、回路体１１０側の中央部に凸となる湾曲した放熱部材７を配置し、回路体１１０の放熱面４ａとは反対側の放熱面１４ａに、回路体１１０側の中央部に凸となる湾曲した放熱部材１７を配置し、放熱部材７および放熱部材１７を弾性変形させて、回路体１１０の放熱面４ａおよび放熱面１４ａに面圧を加えるように、放熱部材７と放熱部材１７とを接続固定する。これにより、放熱面に対する密着が高まり、放熱性能の向上を計ることができる。
　本発明は、上記の実施形態に限定されるものではなく、本発明の特徴を損なわない限り、本発明の技術思想の範囲内で考えられるその他の形態についても、本発明の範囲内に含まれる。また、上述の実施形態と複数の変形例を組み合わせた構成としてもよい。
　１…パワー半導体素子、２…接合材、３…第１の導体、４、１４…絶縁層、４ａ、１４ａ…放熱面、５、１５…熱伝導層、７、１７、１８、１９…放熱部材、７ａ、１７ａ…冷却水路管、７ｃ…テーパ部、８…固定部材、９…接続部材、１０…封止樹脂、１１…導体付きセラミック基板、１１ａ…セラミック基板、１１ｂ…第１導体層、１１ｃ…第２導体層、１２…接合材、１３…第２の導体、１８ａ、１９ａ…放熱フィン、１００、１１０…回路体、２００、２１０…パワー半導体装置。

Claims (15)

  1. 　パワー半導体素子を内蔵した回路体と、
    　前記回路体の第１放熱面側に配置されて前記回路体の熱を放熱する第１放熱部材と、
    　前記回路体の前記第１放熱面とは反対側に配置された固定部材と、を備え、
    　前記第１放熱部材と前記固定部材とが接続固定されることにより、前記第１放熱面側の中央部に凸となる湾曲した前記第１放熱部材が、前記第１放熱面側に密着するように弾性変形されているパワー半導体装置。
  2. 　請求項１に記載のパワー半導体装置において、
    　前記固定部材は、前記第１放熱面側とは反対側の第２放熱面側に配置された第２放熱部材であり、
    　前記第１放熱部材と前記第２放熱部材とが接続固定されることにより、前記第１放熱面側の中央部に凸となる湾曲した前記第１放熱部材および前記第２放熱面側の中央部に凸となる湾曲した前記第２放熱部材が、前記回路体を挟んで前記第１放熱面側と前記第２放熱面側にそれぞれ密着するように弾性変形されているパワー半導体装置。
  3. 　請求項１に記載のパワー半導体装置において、
    　前記第１放熱部材と前記固定部材とを接続固定する部分の前記第１放熱部材の曲げ剛性は、前記第１放熱部材の中央部の曲げ剛性に比べて高いパワー半導体装置。
  4. 　請求項２に記載のパワー半導体装置において、
    　前記第１放熱部材と前記第２放熱部材とを接続固定する部分の前記第１放熱部材および前記第２放熱部材の曲げ剛性は、前記第１放熱部材および前記第２放熱部材の中央部の曲げ剛性に比べてそれぞれ高いパワー半導体装置。
  5. 　請求項３に記載のパワー半導体装置において、
    　前記第１放熱部材と前記固定部材とを接続固定する部分の前記第１放熱部材の板厚は、前記第１放熱部材の中央部の板厚に比べて大きいパワー半導体装置。
  6. 　請求項４に記載のパワー半導体装置において、
    　前記第１放熱部材と前記第２放熱部材とを接続固定する部分の前記第１放熱部材および前記第２放熱部材の板厚は、前記第１放熱部材および前記第２放熱部材の中央部の板厚に比べてそれぞれ大きいパワー半導体装置。
  7. 　請求項１、請求項３、請求項５のいずれか一項に記載のパワー半導体装置において、
    　前記弾性変形された状態における前記第１放熱部材は、前記回路体側に凸状または平坦状であるパワー半導体装置。
  8. 　請求項２、請求項４、請求項６のいずれか一項に記載のパワー半導体装置において、
    　前記弾性変形された状態における前記第１放熱部材および前記第２放熱部材は、前記回路体側に凸状または平坦状であるパワー半導体装置。
  9. 　請求項１に記載のパワー半導体装置において、
    　前記第１放熱部材は、押出成形により形成された複数の冷却水路管を有するパワー半導体装置。
  10. 　請求項２に記載のパワー半導体装置において、
    　前記第１放熱部材および前記第２放熱部材は、押出成形により形成された複数の冷却水路管を有するパワー半導体装置。
  11. 　請求項９または請求項１０に記載のパワー半導体装置において、
    　前記冷却水路管内の側壁は、前記回路体側に向けたテーパ部を形成するパワー半導体装置。
  12. 　請求項１０に記載のパワー半導体装置において、
    　前記複数の冷却水路管の配置密度は、前記第１放熱部材および前記第２放熱部材の中央部に密に配置されるパワー半導体装置。
  13. 　請求項２に記載のパワー半導体装置において、
    　前記第１放熱部材および前記第２放熱部材は、放熱フィンを有するパワー半導体装置。
  14. 　パワー半導体素子を内蔵した回路体の第１放熱面に、前記回路体側の中央部に凸となる湾曲した第１放熱部材を配置し、
    　前記回路体の前記第１放熱面とは反対側の面に固定部材を配置し、
    　前記第１放熱部材を弾性変形させて、前記回路体の前記第１放熱面に面圧を加えるように、前記第１放熱部材と前記固定部材とを接続固定するパワー半導体装置の製造方法。
  15. 　パワー半導体素子を内蔵した回路体の第１放熱面に、前記回路体側の中央部に凸となる湾曲した第１放熱部材を配置し、
    　前記回路体の前記第１放熱面とは反対側の第２放熱面に、前記回路体側の中央部に凸となる湾曲した第２放熱部材を配置し、
    　前記第１放熱部材および前記第２放熱部材を弾性変形させて、前記回路体の前記第１放熱面および前記第２放熱面に面圧を加えるように、前記第１放熱部材と前記第２放熱部材とを接続固定するパワー半導体装置の製造方法。
PCT/JP2020/036784 2019-10-30 2020-09-29 パワー半導体装置およびパワー半導体装置の製造方法 WO2021085006A1 (ja)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004363521A (ja) * 2003-06-09 2004-12-24 Toyota Motor Corp 半導体装置の放熱構造
JP2011129739A (ja) * 2009-12-18 2011-06-30 Fujitsu Ltd 電子装置及びその製造方法
JP2014203892A (ja) * 2013-04-02 2014-10-27 トヨタ自動車株式会社 半導体装置
JP2016082234A (ja) * 2014-10-16 2016-05-16 三菱マテリアル株式会社 冷却器付パワーモジュール用基板及びその製造方法
WO2018146933A1 (ja) * 2017-02-13 2018-08-16 富士電機株式会社 半導体装置及び半導体装置の製造方法
JP2019047049A (ja) * 2017-09-06 2019-03-22 三菱電機株式会社 半導体装置

Family Cites Families (1)

* Cited by examiner, † Cited by third party
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JP6811551B2 (ja) 2016-05-27 2021-01-13 日産自動車株式会社 電力変換装置の製造方法と冷却構造

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004363521A (ja) * 2003-06-09 2004-12-24 Toyota Motor Corp 半導体装置の放熱構造
JP2011129739A (ja) * 2009-12-18 2011-06-30 Fujitsu Ltd 電子装置及びその製造方法
JP2014203892A (ja) * 2013-04-02 2014-10-27 トヨタ自動車株式会社 半導体装置
JP2016082234A (ja) * 2014-10-16 2016-05-16 三菱マテリアル株式会社 冷却器付パワーモジュール用基板及びその製造方法
WO2018146933A1 (ja) * 2017-02-13 2018-08-16 富士電機株式会社 半導体装置及び半導体装置の製造方法
JP2019047049A (ja) * 2017-09-06 2019-03-22 三菱電機株式会社 半導体装置

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