JP2018026370A - Power semiconductor module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve insulation and heat dissipation properties of a resin-sealed power semiconductor module which can have a higher withstand voltage.SOLUTION: A collector electrode of an IGBT 101 and a cathode electrode of a diode 110 are electrically bonded, via a metal bonding part 503, to a collector circuit 203 provided on a ceramic insulation layer 303. A ceramic substrate 13 comprises a metal heat dissipating layer 403, the ceramic insulation layer 303, and the collector circuit 203. Heat generated in the IGBT 101 or the diode 110 is transmitted to a cooler 803 via the metal bonding part 503, the collector circuit 203, the ceramic insulation layer 303, the metal heat dissipating layer 403, and a heat transfer sheet 703. The widths of the metal heat dissipating layer 403 and the heat transfer sheet 703 are smaller than that of the collector circuit 203.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a power semiconductor module.

  In recent years, high-efficiency power conversion devices that use switching of semiconductor elements called power semiconductor chips to save energy have been used in a wide range of fields such as automobiles, railways, industrial equipment, and power equipment. The power semiconductor chip has a high calorific value due to energization and needs to be cooled, and is used in the form of a power semiconductor module in which a conductive material, a heat radiating material, and these insulating materials are mounted.

  The power semiconductor module requires insulation reliability, and a resin that can reduce the thermal stress of the chip from a conventional silicone gel is used. In power semiconductor modules, high reliability is required for insulation.

  As a prior art according to the present invention, for example, there is a structure of a power semiconductor module as described in Patent Document 1 and Patent Document 2.

  In Patent Document 1, in order to relax the electric field at the end of the circuit layer that becomes the electric field concentration portion and improve the insulation, the circuit layer and the insulating layer end between the circuit layer and the metal layer sandwiching the ceramic insulating layer A structure has been proposed in which the distance between is smaller than the distance between the metal layer end and the insulating layer end.

  In Patent Document 2, in order to reduce the size of the power semiconductor module, the relative permittivity of the resin that seals the metal layer and the insulating layer side is made lower than that of the resin that seals the circuit layer and the insulating layer side. A structure having a small gap between the layer end and the insulating layer end and a method for manufacturing the module have been proposed.

JP 2002-270730 A JP 2012-009815 A

  In the structures of Patent Documents 1 and 2, since the ceramic insulating substrate and the base plate are joined with a solder material, the insulation is deteriorated due to the inclination of the solder material or the solder material falling into the side surface of the metal layer. There is a problem.

  In addition, in metal bonding using solder or the like, thermal stress is generated during use. In particular, cracks occur at the end of the metal layer where stress is concentrated, and the generated cracks may propagate to the sealing resin on the base plate and cause deterioration of insulation.

  In the manufacturing process of Patent Document 2, a power semiconductor chip is mounted on a ceramic substrate in order to make the relative dielectric constant of the resin sealing the metal layer and the insulating layer side smaller than the resin sealing the circuit layer and the insulating layer side. Before doing so, a low dielectric constant resin is supplied. When the power semiconductor chip is mounted using a solder material, processing at a high temperature is required. Therefore, the low dielectric constant resin used is limited to a resin having a high heat resistance temperature.

  In addition, since the temperature is higher than the use environment temperature, there is a problem of internal destruction or peeling of a resin having a large thermal stress generated during the process and a low relative dielectric constant.

  The present invention has been made in view of the above problems, and an object of the present invention is to improve the insulation and heat dissipation of a resin-sealed power semiconductor module capable of increasing the breakdown voltage.

  In order to solve the above problems, a power semiconductor module according to the present invention includes a circuit on which a semiconductor element is mounted, an insulating layer disposed on at least one surface of the circuit, and a surface on which the circuit of the insulating layer is disposed. Is a resin seal comprising a metal heat dissipation layer disposed on the opposite surface, and a first insulating material for sealing the circuit, the insulating layer, and the metal heat dissipation layer so that the surface of the metal heat dissipation layer is exposed. A power semiconductor module including a stationary body, wherein the resin sealing body includes a heat transfer sheet disposed on the surface of the metal heat dissipation layer, and the first insulating material and the heat transfer sheet so that the surface of the heat transfer sheet is exposed. A metal heat dissipation layer is projected along the stacking direction of the metal heat dissipation layer and the circuit so that the projected portion of the metal heat dissipation layer is included in the projected portion of the circuit. The heat transfer sheet is a product of the heat transfer sheet and the insulating layer. When projected along a direction, characterized in that the projection portion of the heat transfer sheet is provided to be included projection portion of the insulating layer.

  ADVANTAGE OF THE INVENTION According to this invention, the insulation and heat dissipation of the resin-sealed type power semiconductor module which can make high pressure | voltage resistance can be improved.

1 is an external perspective view of a power semiconductor module according to a first embodiment. It is a circuit diagram of the resin sealing body 901 shown by FIG. FIG. 2 is a perspective view of a resin sealing body 901 and a cooler 803 obtained by removing a first insulating material 601 and a second insulating material 602 from the resin sealing body 901 in FIG. 1. It is a cross-sectional schematic diagram of AA 'of the resin sealing body 901 of FIG. It is a cross-sectional schematic diagram of the resin sealing body 900 which concerns on a comparative example. It is a figure which shows the electric field analysis result of the circuit edge part of the resin sealing body 900 which concerns on a comparative example. It is a figure which shows the electric field analysis result of the circuit edge part of the resin sealing body which concerns on 1st Embodiment. It is a figure which shows the electric field analysis result of the circuit edge part of the resin sealing body which concerns on 1st Embodiment. It is a figure which shows the electric field analysis result of the circuit edge part of the resin sealing body which concerns on 1st Embodiment. It is a cross-sectional schematic diagram of the resin sealing body which concerns on the modification 1 of 1st Embodiment. It is a figure which shows the electric field analysis result of the circuit edge part of the resin sealing body which concerns on the modification 1 of 1st Embodiment. It is an electric field analysis result of the circuit edge part of the resin sealing body 901 which concerns on the modification 2 of 1st Embodiment. It is a figure which shows the manufacturing process of the resin sealing body which concerns on 1st Embodiment. FIG. 12 is a diagram showing a manufacturing process subsequent to FIG. 11. It is an external appearance perspective view after a transfer mold process. It is a figure which shows the resin sealing body after a transfer mold process. It is a figure which shows the next manufacturing process of FIG. It is a figure which shows the modification of 1st Embodiment. It is an external appearance perspective view of the resin sealing body 902 and the water channel 804 which concern on 2nd Embodiment. It is a perspective view of the resin sealing body 902 which concerns on 2nd Embodiment. It is the perspective view which removed the 1st insulating material 601 from the resin sealing body 902 which concerns on 2nd Embodiment. It is a cross-sectional schematic diagram of AA 'of the resin sealing body 902 according to the second embodiment. It is an external appearance perspective view of the resin sealing body 902 and the water channel 804 which concern on the modification of 2nd Embodiment. It is a disassembled perspective view of the resin sealing body 902, the metal case 611, and the water channel 804 which concern on the modification of 2nd Embodiment. It is a cross-sectional schematic diagram of AA 'of the resin sealing body 902 according to a modification of the second embodiment. It is a cross-sectional schematic diagram of AA 'of the resin sealing body 902 according to a modification of the second embodiment. It is a perspective view of the resin sealing body 903 which concerns on 3rd Embodiment. It is a circuit diagram of the resin sealing body 903 which concerns on 3rd Embodiment. It is an external appearance perspective view of the area | region which removed the 1st insulating material 601, the insulating layer 302 on the emitter side, and the metal layers 402U and 402L of the resin sealing body 903 which concerns on 3rd Embodiment. It is a BB 'cross-sectional schematic diagram of the resin sealing body 903 which concerns on 3rd Embodiment.

<First Embodiment>
The power semiconductor module according to the first embodiment will be described with reference to FIGS.

  FIG. 1 is a perspective view of a power semiconductor module according to the present embodiment. The power semiconductor module according to this embodiment includes a resin sealing body 901 and a cooler 803. FIG. 2 is a circuit configuration diagram of the resin sealing body 901 shown in FIG. The resin sealing body 901 has a 1 in 1 circuit shown in FIG. A gate terminal 21 and a sense emitter terminal 25 as control terminals, and an emitter terminal 22 and a collector terminal 23 as power terminals are drawn out. Further, a heat radiating surface 43 (not shown) located on the back surface is a heat radiating surface of the resin sealing body 901. The first insulating material 601 is filled in a region excluding the terminals 21, 22, 23, 25 and the heat radiating surface 43. The resin sealing body 901 is attached to the cooler 803 in a pressed state via a heat transfer sheet 703 (not shown) and a second insulating member 602 (not shown).

  FIG. 3 is a perspective view of a region where the first insulating material 601 and the second insulating material 602 are removed from the resin sealing body of FIG. 1. The resin sealing body 901 is disposed on a surface opposite to the surface on which the semiconductor element is mounted, the insulating layer disposed on at least one surface of the circuit, and the surface of the insulating layer. A metal heat dissipation layer, a first insulating material for sealing the circuit, the insulating layer and the metal heat dissipation layer so that the surface of the metal heat dissipation layer is exposed; a heat transfer sheet disposed on the surface of the metal heat dissipation layer; A first insulating material and a second insulating material for sealing the heat transfer sheet so that the surface of the sheet is exposed.

  In this embodiment, the ceramic insulating layer 303 is used as an insulating layer, and the IGBT 101 and the diode 110 are used as semiconductor elements. The IGBT 101 and the diode 110 are mounted on a circuit pattern 203 provided above the ceramic insulating layer 303. Here, IGBT is an abbreviation for an insulated gate bipolar transistor. A metal heat dissipation layer 403 is provided below the ceramic insulating layer 303. The metal heat dissipation layer 403 has a heat dissipation surface 43 exposed from the first insulating material 601, and the heat dissipation surface 43 is attached to the cooler 803 in a pressed state via a heat transfer sheet 703. Here, the heat transfer sheet is a sheet made of a heat transfer material such as a carbon sheet. The heat transfer sheet is disposed in contact with the heat radiating surface 43 of the metal heat radiating layer.

  Although details will be described later, the width and depth of the metal heat radiation layer 403 and the heat transfer sheet 703 are smaller than the width and depth of the collector circuit 203. Here, the width is the length in the longitudinal direction, and the depth is the length in the short direction.

  4 is a cross-sectional view of the dotted line AA ′ portion of FIG. 3 as viewed from the direction of the arrow. The collector electrode of the IGBT 101 and the cathode electrode of the diode 110 are electrically joined to the collector circuit 203 provided on the ceramic insulating layer through the metal joint portion 503. In FIG. 4, the ceramic substrate 13 includes a metal heat dissipation layer 403, a ceramic insulating layer 303, and a collector circuit 203. The heat generated in the IGBT 101 and the diode 110 is transmitted to the cooler 803 through the metal junction 503, the collector circuit 203, the ceramic insulating layer 303, the metal heat dissipation layer 403, and the heat transfer sheet 703, and is cooled.

  In this embodiment, the metal heat dissipation layer 403 is provided so that the projected portion of the metal heat dissipation layer is included in the projected portion of the circuit when projected along the stacking direction of the metal heat dissipation layer 403 and the collector circuit 203. . Further, the heat transfer sheet 703 is provided so that the projected portion of the heat transfer sheet is included in the projected portion of the insulating layer when projected along the stacking direction of the heat transfer sheet and the insulating layer. That is, the widths of the metal heat radiation layer 403 and the heat transfer sheet 703 are made smaller than the width of the collector circuit 203. When the periphery of the insulating layer is sealed with resin, interface peeling occurs at the interface between the insulating layer and the resin. If interfacial peeling occurs, air breakdown (corona discharge) may occur, and the insulating portion may deteriorate. Therefore, it is necessary to give priority to insulation over heat dissipation, and the width of the metal heat dissipation layer is made smaller than the width of the collector circuit. Comparison verification of insulation reliability between the case where the width of the heat transfer sheet 703 is wider than the width of the collector circuit 203 and the first embodiment will be described using the electric field analysis results shown in FIGS.

  FIG. 5A is a schematic cross-sectional view of a resin encapsulant 900 of a power semiconductor module according to a comparative example of the present invention. The heat transfer sheet 703 of the resin sealing body 900 is provided so that the projected portion of the heat transfer sheet is included in the projected portion of the circuit when projected along the stacking direction of the heat transfer sheet 703 and the collector circuit 203. Absent. That is, the difference from the resin sealing body 901 shown in FIG. 4 is that the width of the heat transfer sheet 703 is larger than the width of the collector circuit 203.

  FIG. 5B shows the electric field analysis result at the end of the collector circuit 203 serving as the electric field concentration portion. Here, the relative dielectric constant of the first insulating material 601 was calculated as 4.5, and the relative dielectric constant of the ceramic insulating layer 303 was calculated as 9.0. Next, FIG. 6 shows the electric field analysis result at the end of the collector circuit 203 which becomes the electric field concentration portion of the resin sealing body 901 of the present embodiment shown in FIG. In order to make the effect easy to understand, the relative dielectric constant of the second insulating material 602 was calculated at 4.5, which is the same as the relative dielectric constant of the first insulating material 601. As a result of the analysis, assuming that the electric field strength of the resin sealing body 900 is 100%, the electric field strength of the resin sealing body 901 is reduced by about 20% to 81%. This decrease in electric field strength is due to the fact that the heat transfer sheet having high conductivity takes a certain distance from the end of the collector circuit, and is due to the expansion of the insulation distance. Due to the decrease in the electric field strength, the module breakdown voltage and the corona discharge resistance can be improved.

  The effect range of this configuration will be described with reference to FIGS. FIG. 7 shows that the width of the heat transfer sheet 703 is reduced to the same as that of the ceramic insulating layer 303, and a second insulating material having a relative dielectric constant of 4.5 is provided in the space between the cooler and the resin sealing body generated thereby. It is a calculation result when installed. FIG. 8 shows a case where the width of the heat transfer sheet 703 is reduced to the same level as the collector circuit 203 and a second insulating material having a relative dielectric constant of 4.5 is installed in the space between the generated cooler and the resin sealing body. Is the calculation result of Compared with the resin sealing body shown in FIG. 5, the electric field strengths of the resin sealing bodies shown in FIGS. 7 and 8 were reduced by 2% and 10%, respectively. Therefore, the effect of reducing the electric field strength appears when the width of the heat transfer sheet 703 is reduced to the width of the ceramic insulating layer 303, and is sufficiently reduced by reducing the width of the heat transfer sheet 703 to the vicinity of the width of the collector circuit. It turned out to be effective. Therefore, when projected along the stacking direction of the heat transfer sheet and the insulating layer, it is preferable that the projected portion of the heat transfer sheet is included in the projected portion of the insulating layer. The reduction of the electric field strength shown in FIG. 7 and FIG. 8 is not due to the expansion of the insulation distance, but the electric field concentrates at the end of the heat transfer sheet when the end of the heat transfer sheet approaches the end of the collector circuit, This is a result of the electric field concentration of the collector circuit being dispersed.

  Below, the material which comprises the power semiconductor module of this invention is demonstrated.

  For the ceramic insulating layer 303, aluminum nitride, silicon nitride, alumina, or the like having a high withstand voltage is used. In particular, aluminum nitride or silicon nitride having high thermal conductivity is desirable. The thickness of the ceramic insulating layer 303 is set in the range of 0.1 to 1.5 mm in accordance with the insulating characteristics required for the power semiconductor module. The ceramic insulating layer may have a sheet-like configuration in which a resin is matrixed and a high thermal conductive filler such as alumina, boron nitride, yttria (yttrium oxide), or aluminum nitride is mixed.

  The collector circuit 203 is made of copper, aluminum, or an alloy thereof having low electrical resistance. Between the collector circuit 203 and the ceramic insulating layer, an intermediate layer made of molybdenum, tungsten or carbon having a low thermal expansion and high thermal conductivity, or a composite material of these materials and copper or aluminum may be provided. In this embodiment, the intermediate layer is omitted. The thickness of the collector circuit 203 is set in a range of 0.2 to 2.0 mm in accordance with a necessary current capacity.

  For the metal heat dissipation layer 403, copper, aluminum, or an alloy thereof having high thermal conductivity is used. Similarly to the circuit side, an intermediate layer made of molybdenum, tungsten, or carbon with a low thermal expansion and high thermal conductivity between the metal heat dissipation layer and the ceramic insulating layer, or a composite material of these materials and copper or aluminum may be installed. Good. In this embodiment, the intermediate layer is omitted.

As the first insulating material 601, for example, an adhesive novolak, polyfunctional, biphenyl, phenol type epoxy resin, bismaleimide triazine, or cyanate ester can be used. These _{resins, SiO 2, Al 2 O 3} , AlN, ceramics or gels such as BN, contain a filler such as rubber, closer thermal expansion coefficient 3~23ppm / K and IGBT or circuit 203, the coefficient of thermal expansion To reduce the difference. The Young's modulus is set in the range of 1 to several tens of GPa. By using such a resin having a coefficient of thermal expansion or Young's modulus, the thermal stress generated as the temperature rises in the environment of use is significantly reduced, so that the life of the power semiconductor module can be extended.

  For example, a low-temperature sintered bonding material mainly composed of solder material, fine metal particles, and metal oxide particles is used for the metal bonding portion 503. As the solder material, solder whose main component is tin, bismuth, zinc, gold or the like whose melting point is higher than the curing temperature of the first insulating material 601 can be used. The fine metal particles are fine particles of silver or copper coated with an aggregation protective material, and in particular, the aggregation protective material that can be removed at a low temperature equivalent to the solder material is applicable. As the metal oxide particles, a metal oxide that can be reduced at a low temperature equivalent to a solder material such as silver oxide or copper oxide is applicable. When fine silver particles, fine copper particles, silver oxide, and copper oxide particles are used, the metal joint becomes a sintered silver layer or a sintered copper layer.

  For the heat transfer sheet 703, a sheet-like material having high thermal conductivity is used. A material having a Young's modulus lower than that of the metal heat dissipation layer 403 and the first insulating material 601 is used. By making the Young's modulus of the heat transfer sheet 703 smaller than that of the first insulating material 601, the thermal stress can be reduced, which is effective for improving the reliability of the resin sealing body. Specifically, the Young's modulus of the heat transfer sheet 703 is preferably 1 to 500 MPa. When the resin sealing body 901 is warped and deformed under the usage environment, the heat transfer sheet 703 is deformed and protrudes to the outer peripheral portion to deteriorate the insulating property. Therefore, the Young's modulus is preferably larger than 1 MPa. In particular, from the viewpoint of high heat conduction, a highly heat conductive conductive metal or carbon-based sheet is more desirable. Furthermore, a structure having improved flexibility can be obtained by adding a carbon filler to an acrylic, silicone, or urethane-based resin. Further, an installation structure in which the surface of the metal heat radiation layer 403 is exposed and the heat transfer sheet 703 is brought into close contact with both the metal heat radiation layer 403 and the cooler 803 without being chemically or metallicly bonded. By doing so, it is possible to reduce the stress generated in the sheet. By disposing a heat transfer sheet instead of a solder material between the metal heat dissipation layer and the cooler, the assembling property of the resin-encapsulated body is improved and the manufacture becomes simple.

  As the second insulating material 602, an insulating resin can be used. By installing the second insulating material 602, it is possible to improve the insulating property as compared with the case where the second insulating material is not installed. By adopting an installation structure in which the second insulating material 602 is not chemically or metallicly bonded but is brought into close contact with the pressure, stress generated in the second insulating material 602 can be reduced. In addition, in order to make a 2nd insulating material into a sheet form, it is possible to perform a hardening process in advance.

  Moreover, the reliability of a heat-transfer sheet | seat can be improved by using a material with low hardness about a 2nd insulating material. It is preferable that the hardness of the second insulating material is first insulating material> heat transfer sheet> second insulating material.

  The resin sealing body radiates heat through the heat transfer sheet 703 when the second insulating material 602 and the heat transfer sheet 703 are pressed. The second insulating material 602 is preferably a material having a Young's modulus smaller than that of the first insulating material 601 and the heat transfer sheet 703 so that the heat transfer sheet 703 can be pressed under the usage environment. Such materials include thermoplastic elastomers, silicone gels, etc., in addition to acrylic, silicone, and urethane resins. The Young's modulus is preferably less than 1 MPa. Thus, if the supply thickness is set slightly thicker than the heat transfer sheet by making it softer than the heat transfer sheet, it can be compressed until a sufficient pressing force is generated on the heat transfer sheet when pressed. .

  Below, the effect obtained by this embodiment is demonstrated.

  In the present embodiment, when the metal heat dissipation layer is projected along the stacking direction of the metal heat dissipation layer and the circuit, the projection portion of the metal heat dissipation layer is provided so as to be included in the projection portion of the circuit, and the heat transfer sheet is When projected along the stacking direction of the heat transfer sheet and the insulating layer, the projected portion of the heat transfer sheet is provided so as to be included in the projected portion of the insulating layer. Thus, by reducing the width of the metal heat radiation layer 403 and the heat transfer sheet 703 with respect to the circuit layer 203, the electric field at the circuit end that becomes the electric field concentration portion can be reduced. As a result, the corona discharge start extinction voltage and the breakdown voltage of the resin sealing body 901 can be improved. As a result, the insulation reliability of the power semiconductor module can be improved.

  Moreover, in this embodiment, in order to maintain the reliability of an insulation part under use environment, a power semiconductor module is provided with the resin sealing body of the following structures. The surface of the metal heat dissipation layer 403 is exposed, and the first insulating material 601 is present on the same plane. The first insulating material 601 is bonded to the side surface of the metal heat dissipation layer 403. With these structures, even if the heat transfer sheet 403 is installed wider than the metal heat dissipation layer 403, the heat transfer sheet does not enter the side surface of the metal heat dissipation 403, so that the insulation reliability can be improved. .

  The heat transfer sheet 703 is disposed in contact with the exposed surface of the metal heat dissipation layer 403. The heat transfer sheet 703 is an installation structure in which both the metal heat radiation layer 403 and the cooler 803 are in close contact with each other without being chemically or metallicly bonded. Thus, since the resin sealing body 901 is not directly bonded or bonded to the cooler 803 via the metal heat dissipation layer 403 or the first insulating material 601, it is generated in the heat transfer sheet portion or the sealing resin portion. The thermal stress to be reduced can be greatly reduced.

  Furthermore, by installing the second insulating material 602 on the outer peripheral portion of the heat transfer sheet 703, it is possible to improve insulation and suppress the protrusion of the heat transfer sheet to the outer peripheral portion.

  The first portion having a higher Young's modulus than the heat transfer sheet 703 and the second insulating material 602 with respect to the end of the circuit 203 where the thermal stress increases, the end of the ceramic insulating layer 303, and the end of the metal heat dissipation layer 403 By sealing with the insulating material 601, thermal stress can be reduced. This makes it possible to reduce warping deformation of the resin sealing body 901 and reduce thermal stress generated in the heat transfer sheet 703 and the second insulating material 602. Further, the insulating material covering the end portion of the ceramic insulating layer 303 where the stress is concentrated is sealed using one kind of material. As a result, it is possible to separate the advancing portion when the generation of the interfacial stress or the crack, which becomes a problem when sealing with two or more kinds of materials, from the interface with the ceramic insulating layer 303, and the insulation is improved.

<Variation 1 of the first embodiment>
A first modification of the power semiconductor module according to the first embodiment having excellent insulation will be described with reference to FIG.

  FIG. 9A is a cross-sectional view of AA ′ of FIG. 3 viewed from the direction of the arrow. The resin encapsulant included in the power semiconductor module according to Modification 2 is configured such that when the metal heat dissipation layer is projected along the stacking direction of the heat transfer sheet and the metal heat dissipation layer, the projected portion of the metal heat dissipation layer is It is provided so as to be included in the projection part. Further, the heat transfer sheet is provided so that the projected portion of the heat transfer sheet is included in the projected portion of the collector circuit when projected along the stacking direction of the heat transfer sheet and the circuit. That is, the heat transfer sheet layer 703 is different from the resin sealing body of FIG. 4 in that the width of the heat transfer sheet layer 703 is larger than the metal heat dissipation layer 403 and smaller than the circuit layer 203. FIG. 9B shows the result of electric field analysis. The electric field strength was 83%, and compared with FIG. 5 (b), the electric field strength could be reduced by 17%. From this result, even if the width of the heat transfer sheet is larger than the width of the metal heat dissipation layer, if the width of the heat transfer sheet is smaller than the width of the circuit layer, there is an effect of improving the insulation performance to the same extent as the first embodiment I understand.

  Furthermore, the effect which can exhibit the heat spreading effect of the planar direction inside a heat exchanger sheet is added by enlarging the width | variety of a heat exchanger sheet. With this configuration, it is possible to reduce the thermal resistance of the resin sealing body 901 as compared with the first embodiment of FIG.

<Modification 2 of the first embodiment>
A modification 2 of the power semiconductor module according to the first embodiment having excellent insulation will be described with reference to FIG.

  The resin sealing body included in the power semiconductor module according to Modification 2 is different from the first embodiment in that the second insulating material 602 has a lower relative dielectric constant than the first insulating material 601. FIG. 10 shows the electric field analysis results. In the second modification, the relative dielectric constant of the second insulating material is 3.5, and the relative dielectric constant of the first insulating material 601 is 4.5.

  As shown in FIG. 10, the electric field strength can be reduced to 75% by using the second insulating material having a relative dielectric constant lower than that of the first insulating material. Compared with the first embodiment, the insulation performance can be improved.

<Manufacturing process>
Hereinafter, an example of the manufacturing process of the power semiconductor module according to the present invention will be described with reference to FIGS.

  FIG. 11 shows a process of mounting the IGBT 101 and the diode 110 on the collector circuit 203 of the ceramic substrate 13. The collector electrode of IGBT 101 and the cathode electrode of diode 110 are electrically joined to collector circuit 203 via metal junction 503. Bonding between the metal bonding portion and the circuit layer is performed by heating to 250 to 350 ° C. in hydrogen or an inert atmosphere.

  When the ceramic insulating layer has a sheet-like configuration in which a resin is matrixed and a high thermal conductive filler such as alumina, boron nitride, yttria, or aluminum nitride is mixed, the metallized layer is bonded after the metal bonding portion 503 is bonded from the viewpoint of heat resistance. The process of attaching with 403 is desirable.

  The circuit 203 and the metal heat dissipation layer 403 are bonded to the ceramic insulating layer 303 using, for example, a brazing material that can be firmly bonded. The melting point of the brazing material is preferably higher than the temperature at which the IGBT 101 and the diode 110 are joined to the collector circuit 203. At this time, it is desirable to make the thermal stress obtained from the difference in thermal expansion coefficient and the Young's modulus between the circuit and the metal heat dissipation layer equal across the ceramic insulating layer. In the present embodiment, since the width of the circuit is wider than the width of the metal heat dissipation layer, it is preferable to make the circuit slightly thicker when materials having the same composition are used.

  FIG. 12 shows a process of mounting a gate terminal 21 and a sense emitter terminal 25 as control terminals, and an emitter terminal 22 and a collector terminal 23 as power terminals. As shown in FIG. 12, the control terminal gate terminal 21 and the sense emitter terminal 25, and the power terminal emitter terminal 22 and the collector terminal 23 are integrated in a strip shape. The gate electrode of the IGBT 101 is ultrasonically bonded to the gate terminal 21 using a wire or ribbon made of Al or Cu having a low electrical resistance (not shown). Similarly, the emitter electrode of the IGBT 101 and the anode electrode of the diode 110 are ultrasonically bonded to the emitter terminal 22 using an Al or Cu wire or ribbon having a low electrical resistance (not shown). The collector circuit 203 is ultrasonically bonded to the collector terminal 23 using a wire or ribbon made of Al or Cu having a low electrical resistance (not shown). The sense emitter terminal 25 is ultrasonically bonded by using a sense emitter electrode when the IGBT 101 has a sense emitter electrode, or by using an Al or Cu wire or ribbon having a low electric resistance with respect to the emitter electrode if not present (not shown). ) Instead of Al or Cu wires or ribbons, an Al or Cu lead material may be prepared and bonded using the metal bonding portion 503. In that case, the steps shown in FIG. 7 can be performed simultaneously.

  FIG. 13A shows an external perspective view after the transfer molding process. The above-described band-shaped integrated portion 20 is cut after sealing, and insulation between terminals is ensured, whereby a resin sealing body 901 shown in FIG. 13B is completed.

  It is preferable that the sealing curing temperature of the first insulating material 601 is in the range of 150 to 200 ° C. Before sealing with the first insulating material 601, the circuit, the terminal, the ceramic insulating layer, the metal heat dissipation layer, the semiconductor chip, and the metal joint are subjected to a treatment for improving the adhesion strength with the first insulating material 601. It is desirable. For example, a method of forming a coating film such as polyamideimide or polyimide or a method of roughening the surface is employed.

  FIG. 14 shows a process of attaching the resin sealing body 901 to the water channel 803. The second insulating material 602 has a frame shape. For example, the outer shape can be easily aligned with the outer shape of the first insulating material 601. In the first embodiment, the outer shape is matched with that of the first insulating material 601, but it is also possible to match with the water channel. On the other hand, the inner diameter of the frame-like shape of the second insulating material can be easily aligned in accordance with the outer shape of the heat transfer sheet 703. Productivity can be improved because alignment is facilitated. It installs in a waterway in this state, and is set as the state pressed with the volt | bolt or the spring pressurization.

  Moreover, as shown in FIG. 1, it is also possible to install a plurality of resin sealing bodies in one water channel, and the second insulating material 602 is provided with a frame on which a plurality of heat transfer sheets 703 can be installed. Thus, it is possible to enable alignment.

  Below, the effect obtained by this embodiment is demonstrated.

  The order of heat resistance required in the usage environment of the resin sealing body 901 is the order of the metal joint portion 503, the first insulating material 601, the heat transfer sheet 703, and the second insulating material 602. On the other hand, even if the process temperature is higher than the temperature assumed in the use environment, the order of the manufacturing process is the order of the heat-resistant temperature required in the use environment as in this embodiment. It is possible to reduce the thermal stress generated during the process. Thereby, the crack, peeling, etc. which generate | occur | produce in an insulation part can be prevented, and the insulation reliability of a power semiconductor module can be improved.

  As in this embodiment, the gate terminal 21, the emitter terminal 22, the collector terminal 23, and the sense emitter terminal 25 are drawn from the same plane. Thereby, when installing the 1st insulating material 601 in the metal mold | die of a transfer mold, the position between terminals can be positioned with high precision. When the displacement occurs, excessive stress occurs during resin leakage or mold clamping. By performing transfer molding using the band-shaped integrated portion 20, one surface of the metal heat dissipation layer 403, which is a heat dissipation surface, is exposed, and these members are not exposed to brittle members such as the IGBT 101, the diode 110, and the ceramic 303. Can be sealed with resin 601. Thereby, the heat radiation surface can be installed in parallel to the first insulating material 601, and the clearance with the water channel 803 can be set in parallel. In addition, the first insulating material 601 can be present on the same plane of the exposed metal heat dissipation layer 403. Thereby, the uniformity at the time of a press can be provided. In addition, since the first insulating material 601 covers brittle members such as the IGBT 101, the diode 110, and the ceramic 303, it is possible to prevent direct stress and to perform additional processing such as grinding or machining. Become.

<Modification 2 of Manufacturing Process>
FIG. 15 shows a process of attaching the resin sealing body 901 to the water channel 803. The heat transfer sheet 703 is installed in a state where it is temporarily attached to the heat radiation surface 43 of the resin sealing body 901 and pressed with a bolt or a spring. A frame-shaped third insulating member 603 is attached to the water channel side. The second insulating material 602 is injected into the remaining space on the outer periphery of the heat transfer sheet 703. Thereafter, heat treatment is performed to cure the insulating material. For the frame-shaped third insulating member 603, for example, a thermoplastic insulating material such as PPS or PBT is used.

  Although not shown in the figure, the water channel and the resin sealing body are positioned by providing the frame-shaped wall surface 603 formed of an insulating material with recesses and through holes for installing the terminals 21, 22, 23, and 25 of the resin sealing body. Is possible. It is also possible to use a frame-shaped third insulating member 603 as a supporting part for the pressure component.

Second Embodiment
An example of the power semiconductor module according to the present invention will be described with reference to FIGS. In the second embodiment and the third embodiment, the description of the same configuration as that of the first embodiment is omitted.

  FIG. 16 is a perspective view of an example of a power semiconductor module according to the present invention. The plurality of resin sealing bodies 902 are sandwiched between the plurality of water channels 804 via the heat transfer sheet 703 (not shown). The resin sealing body 902 shown in FIG. 17 has the 1 in 1 circuit shown in FIG. 2 as in the first embodiment. In the figure, a heat radiation surface 42 located on the front surface and a heat radiation surface 43 (not shown) located on the back surface are heat radiation surfaces of the resin sealing body 902, respectively. The control terminal gate terminal 21 and the sense emitter terminal 25, and the power terminal emitter terminal 22 and the collector terminal 23 are drawn out in the same direction. The first insulating material 601 is filled in a region excluding the terminals 21, 22, 23, 25 and the heat radiation surfaces 42, 43.

  FIG. 18 is a perspective view of a region where the first insulating material 601 is removed from FIG. In the present embodiment, two IGBTs 101 and two diodes 110 are provided as power semiconductor devices to be mounted. The two IGBTs 101 and the two diodes 110 are in the form of being sandwiched between a ceramic substrate 12 on the emitter electrode side and a ceramic substrate 13 on the collector electrode side having circuit patterns and metal heat dissipation layers on the front and back sides (helping understanding). For illustration).

  FIG. 19 is a cross-sectional view taken along a dotted line AA ′ in FIG. The collector electrode of the IGBT 101 is electrically bonded to the collector circuit 203 provided on the insulating substrate 13 having the metal heat dissipation layer 403 and the ceramic insulating layer 303 via the metal bonding portion 503. The emitter electrode 102 of the IGBT 101 is electrically bonded to the emitter circuit 202 provided on the insulating substrate 12 having the metal heat dissipation layer 402 and the ceramic insulating layer 302 via the metal bonding portion 502 and the protruding portion 202A.

  Further, heat radiation surfaces 42 and 43 are formed on the surface of the ceramic substrates 12 and 13 opposite to the IGBT mounting surface. The heat generated in the active portion of the IGBT 101 has two paths: a path for transferring heat through the insulating substrate 13 and a path for transferring heat through the insulating substrate 12 from the protrusion 202A in the vertical direction. A power semiconductor module including a resin sealing body having front and back directions and two heat radiation paths is defined as a double-sided cooling type power semiconductor module.

  The protrusion 202A provided in the emitter circuit 202 has a function of controlling the insulation distance between the emitter circuit 202 and the collector circuit 203 determined from the insulation characteristics of the first insulating material 601. The protrusion 202A has a shape in which the width and depth of the installation surface are larger than the thickness so that the protrusion 202A can be independent during the joining process. Next, the thickness of the protruding portion 202A is made larger than that of the metal joint portion 502, so that the inclination and thickness variation during joining are reduced. Furthermore, in order to improve assemblability, the width and depth of the installation surface of the protrusion 202A to the emitter electrode 102 are made smaller than those of the emitter electrode 102.

  For the protrusion 202A, it is desirable to select copper, aluminum, molybdenum, tungsten, carbon, an alloy thereof, or a composite material having high thermal conductivity so as to have low electrical resistance and low thermal resistance. Moreover, you may install them and you may install the low thermal expansion intermediate | middle layer with respect to copper or aluminum. In this embodiment, the intermediate layer is omitted.

  As in the first embodiment, the ceramic insulating layers 302 and 303 are made of aluminum nitride, silicon nitride, alumina or the like having a high withstand voltage. In the resin sealing body of the power semiconductor module according to the second embodiment, the deformation due to the thermal stress of the resin sealing body can be reduced by making the thicknesses of the ceramic insulating layers on the front and back sides equal.

  The same material as that of the first embodiment can be used for the emitter circuit 202 and the collector circuit 203 on which the emitter electrode 102 and the collector electrode 103 which are the main electrodes of the IGBT 101 are mounted. Moreover, you may install an intermediate | middle layer similarly to 1st Embodiment.

  For the metal heat dissipation layers 402 and 403, the same material as that of the first embodiment can be used. Further, an intermediate layer may be provided between the metal heat dissipation layer and the ceramic insulating layer as in the first embodiment.

  The circuit portions 202 and 203 and the metal heat dissipation layers 402 and 403 are bonded using, for example, a brazing material that can be firmly bonded to the ceramics 302 and 303. At this time, it is desirable to make the thermal stress obtained from the difference between the thermal expansion coefficient and the Young's modulus between the circuit and the metal heat dissipation layer equal across the ceramic insulating layer.

  A material similar to that of the first embodiment can be used for the first insulating material 601. Before sealing the first insulating material 601 with the above-described resin, the first insulating material 601 and the adhesion strength with respect to the circuit, terminal, ceramic insulating layer, metal heat dissipation layer, semiconductor chip, and metal joint portion. It is desirable to perform a process for improving the above. For example, a method of forming a coating film such as polyamideimide or polyimide is employed.

  The same material as that of the first embodiment can be used for the metal joint portions 502 and 503, the heat transfer sheets 702 and 703, and the second insulating material that join the emitter electrode 102 and the collector electrode 103.

  In the resin sealing body according to the second embodiment, when the collector circuit 203, the metal heat radiation layer 403, and the heat transfer sheet 703 are projected along the stacking direction, the projected portion of the metal heat dissipation layer is the projected portion of the collector circuit and the heat transfer. The projection part of the sheet is included in the projection part of the sheet, and the projection part of the heat transfer sheet is included in the projection part of the collector circuit. Therefore, the width of the collector circuit 203 is larger than the width of the metal heat dissipation layer 403. The width of the heat transfer sheet 703 is smaller than the width of the collector circuit 203 and larger than the width of the metal heat dissipation layer 403.

  In addition, when projected along the stacking direction of the emitter circuit 202, the metal heat radiation layer 402, and the heat transfer sheet 702, the projection part of the metal heat dissipation layer is included in the projection part of the emitter circuit and the projection part of the heat transfer sheet. The projected part of the sheet is included in the projected part of the emitter circuit. Therefore, the width of the emitter circuit 202 is larger than the width of the metal heat dissipation layer 402. The heat transfer sheet 702 is smaller than the width of the emitter circuit 202 and larger than the width of the metal heat dissipation layer 402.

  Thus, by making the width of the heat transfer sheets 702 and 703 smaller than the width of the ceramic insulating layers 302 and 303, the electric fields at the ends of the emitter circuit 202 and the collector circuit 203 serving as electric field concentrating portions are relaxed, and resin sealing is performed. The insulation performance of the body 902 can be improved. As a result, the insulation reliability of the power semiconductor module can be improved.

<Modification Example 1 of Second Embodiment>
20 to 22 show an example of a power semiconductor module according to the present invention. FIG. 20 is a perspective view of the second embodiment. A power semiconductor module according to Modification 1 of the second embodiment includes a partition member (metal case) 611 having an opening on one side and a recess on the other side, and a resin seal housed in the opening on the one side And a cooler 804 housed in the recess on the other side, and the resin-sealed body is housed so as to be sandwiched by the cooler via a partition member (metal case).

  FIG. 21 is an assembly diagram for helping understanding. A plurality of resin sealing bodies 902 are inserted into openings provided on the upper surface of the metal case 611, and a plurality of water channels 804 are alternately inserted into recesses provided on the lower surface.

  FIG. 22 is a schematic cross-sectional view of the insertion portion AA ′ of the power semiconductor module of FIG. 20, which is rotated 90 ° counterclockwise. A metal case 611 exists between the resin sealing body 902 and the water channel 804, and heat transfer sheets 702 and 703 are respectively provided at the interfaces between the heat radiation surfaces 42 and 43 of the resin sealing body 902 and the metal case 611. Yes.

  With this structure, it is possible to fill the second insulating material 602 without leaking from the opening of the metal case 611 after the resin sealing body 902 is installed in the water channel 804 in a pressed state. Here, a difference is that a case 611 for installing the insulating material 602 in the heat transfer path is provided. In order to improve the cooling performance of the resin sealing body 902, the metal case 611 is preferably made of Cu, Al, or an alloy thereof having high thermal conductivity. Further, the metal case 611 is preferably thin, and is preferably less than 1 mm.

<Modification 2 of the second embodiment>
Modification 2 of 2nd Embodiment is demonstrated using FIG. FIG. 23 is a schematic cross-sectional view of the insertion portion AA ′ of the power semiconductor module of FIG. 20, which is rotated 90 ° counterclockwise. A metal case 611 exists between the resin sealing body 902 and the water channel 804. The metal case 611 has a structure having an opening only in one direction on the terminal side of the resin sealing body 902. Heat transfer sheets 702 and 703 are provided on the interfaces between the heat radiation surfaces 42 and 43 of the resin sealing body 902 and the metal case 611, respectively. Here, the difference is that heat transfer sheets 704 and 705 are also installed at the interface between the water channel 804 and the metal case 611.

  In the present embodiment, the width of the heat transfer sheet installed on the water channel side outside the metal case 611 is made smaller than the width of the water channel 804. By setting it as such a structure, when the resin sealing body 902 is installed in the water channel 804 in the press state, the metal case 611 of the outer peripheral part of the heat-transfer sheets 702 and 703 deform | transforms into a water channel side. The distance of the metal case 611 from the edge part of the emitter circuit 202 and the collector circuit 203 which become an electric field concentration part can be separated. As a result, the electric field at the ends of the emitter circuit 202 and the collector circuit 203 can be relaxed, and the insulating performance of the resin sealing body 902 can be improved.

<Third Embodiment>
An example of the resin sealing body according to the present invention will be described with reference to FIGS.

  FIG. 24 is a perspective view of a power semiconductor module according to the present invention. Here, the second embodiment is different from the second embodiment in that the circuit of the resin sealing body 903 has a 2-in-1 circuit configuration shown in FIG. A structure in which the two arm circuits of the upper arm circuit and the lower arm circuit are integrated into a module like the power semiconductor module of the third embodiment is referred to as a 2-in-1 structure. The 2-in-1 structure can reduce the number of output terminals compared to the 1-in-1 structure in which each arm circuit is modularized. In the present embodiment, an example of a 2in1 structure is shown, but the number of terminals can be further reduced by using a 3in1 structure, a 4in1 structure, a 6in1 structure, or the like. In a power semiconductor module provided with a 2-in-1 resin encapsulant, an upper arm circuit and a lower arm circuit are arranged side by side and arranged opposite to a metal flat plate with an insulating layer interposed therebetween, thereby reducing the inductance of the circuit due to a magnetic field canceling effect. be able to.

  In the third embodiment, two IGBTs 101 and two diodes 110 are mounted. The resin sealing body 903 is a series of an upper arm IGBT 101U and a lower arm IGBT 101L. Further, 42U and 42L, 43U and 43L which are front and back surfaces of the resin sealing body 903 are cooling surfaces. Also, gate terminals 21U and 21L of the upper and lower arms as control terminals, sense emitter terminals 25U and 25L of the upper and lower arms, emitter terminals (DC negative electrode connection terminals) 22L of the lower arm as power terminals, collector terminals (DC positive electrodes) of the upper arm Connection terminal) 23U and intermediate terminal (AC connection terminal) 24M are each drawn out from the first insulating material 601 in the same direction.

  FIG. 26 is a perspective view of a region excluding the first insulating material 601, the insulating layer 302 of the ceramic substrate 12, and the heat radiation portions 402 </ b> U and 402 </ b> L in order to facilitate understanding of the circuit diagram. The upper arm IGBT 101U and the diode 110U have a collector electrode and a cathode electrode connected to the collector circuit 203U, and an emitter electrode and an anode electrode connected to the emitter circuit 202U. The lower arm IGBT 101L and the diode 110L have a collector electrode and a cathode electrode connected to the collector circuit 203L, and an emitter electrode and an anode electrode connected to the emitter circuit 202L. The IGBT 101 is provided with a gate electrode and a sense emitter electrode, and is connected to terminals 21 and 25. The upper arm emitter circuit 202U and the lower arm collector circuit 203L are connected to each other through the intermediate electrode 202M. In this way, the upper arm circuit and the lower arm circuit are electrically connected by the intermediate electrode 202M, and an upper and lower arm series circuit as shown in FIG. 25 is formed.

  FIG. 27 is a schematic cross-sectional view taken along dotted line BB ′. On the chip mounting surface of the insulating layer 302, upper and lower arm emitter circuits 202U and 202L are provided. On the back surface, metal heat radiation layers 402U and 402L of upper and lower arms to be heat radiation layers are respectively provided. The widths of the metal layers 402U and 402L are made smaller than the respective emitter circuits 202U and 202L. Moreover, also about the heat-transfer sheet | seat 702, the space which can install the 2nd insulating material 602B is provided by providing 702U and 702L, respectively. The same applies to the insulating layer 303 side. With this structure, even in a 2 in 1 circuit, the electric field at each end of the emitter and collector circuits that become the electric field concentration portion can be relaxed, and the insulating performance of the resin sealing body 903 can be improved. .

  Since the metal heat dissipation layers 402U, 402L, 403U, and 403L are sealed by the first insulating material 601 except for the heat dissipation surface, it is possible to make each heat dissipation surface the same plane. As a result, the heat transfer sheets 702U, 702L, 703U, and 703L can be made uniform in clearance when a plurality of sheets are used. Furthermore, by covering the side surfaces of the metal heat radiation layers 402U, 402L, 403U, and 403L, and the presence of the second insulating material 602 on the outer periphery, the metal heat radiation layers of the heat transfer sheets 702U, 702L, 703U, and 703L Intrusion to the side can be prevented. These effects make it possible to maintain the insulation reliability in the environment of use.

  In the present embodiment, the productivity in the manufacturing process can be improved by integrating the insulating layers 302 and 303 with the circuit of the upper and lower arms and the metal heat dissipation layer. However, since the first insulating material 601 and the upper and lower arms can be integrated and the above effect can be exhibited, the insulating layers 302U and 302L can also be divided.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the present invention described in the claims. It can be changed. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. Furthermore, it is possible to add, delete, or replace other configurations for a part of the configuration of each embodiment.

DESCRIPTION OF SYMBOLS 12 ... Ceramic substrate, 13 ... Ceramic substrate, 101 ... IGBT, 110 ... Diode, 21 ... Gate terminal, 22 ... Emitter terminal, 23 ... Collector terminal, 24 ... Intermediate terminal, 25 ... Sense emitter terminal, 202 ... Emitter circuit, 203 DESCRIPTION OF SYMBOLS ... Collector circuit 302 ... Ceramic insulating layer 303 ... Ceramic insulating layer 42 ... Heat radiation surface 43 ... Heat radiation surface 402 ... Metal heat radiation layer 403 ... Metal heat radiation layer 502 ... Metal joint part 503 ... Metal joint part 601 ... first insulating material, 602 ... second insulating material, 603 ... third insulating material, 611 ... metal case, 702 ... heat transfer sheet, 703 ... heat transfer sheet, 803 ... water channel, 804 ... water channel

Claims (13)

A circuit on which a semiconductor element is mounted;
An insulating layer disposed on at least one surface of the circuit;
A metal heat dissipating layer disposed on a surface opposite to the surface on which the circuit of the insulating layer is disposed;
A first insulating material for sealing the circuit, the insulating layer, and the metal heat dissipation layer so that a surface of the metal heat dissipation layer is exposed;
A power semiconductor module comprising a resin encapsulant comprising:
The resin sealing body seals the heat transfer sheet disposed on the surface of the metal heat dissipation layer, the first insulating material, and the heat transfer sheet so that the surface of the heat transfer sheet is exposed. Two insulation materials,
The metal heat dissipation layer is provided so that the projected portion of the metal heat dissipation layer is included in the projected portion of the circuit when projected along the stacking direction of the metal heat dissipation layer and the circuit,
When the heat transfer sheet is projected along the stacking direction of the heat transfer sheet and the insulating layer, the heat transfer sheet is provided so that the projected portion of the heat transfer sheet is included in the projected portion of the insulating layer. Power semiconductor module. The power semiconductor module according to claim 1,
When the heat transfer sheet is projected along the stacking direction of the heat transfer sheet and the circuit, the projected portion of the heat transfer sheet is provided so as to be included in the projected portion of the circuit. Semiconductor module. The power semiconductor module according to claim 1,
The metal heat dissipation layer is provided so that the projection of the metal heat dissipation layer is included in the projection of the heat transfer sheet when projected along the stacking direction of the heat transfer sheet and the metal heat dissipation layer. A power semiconductor module. The power semiconductor module according to claim 1,
When the heat transfer sheet is projected along the stacking direction of the heat transfer sheet and the circuit, the projection part of the heat transfer sheet is provided so as to be included in the projection part of the circuit,
The metal heat dissipation layer is provided so that the projected portion of the metal heat dissipation layer is included in the projected portion of the heat transfer sheet when projected along the stacking direction of the heat transfer sheet and the metal heat dissipation layer. Power semiconductor module characterized by A power semiconductor module according to any one of claims 1 to 4,
The power semiconductor module is characterized in that the hardness of the heat transfer sheet is smaller than the hardness of the first insulating material. A power semiconductor module according to any one of claims 1 to 4,
The power semiconductor module, wherein the hardness of the second insulating material is smaller than the hardness of the first insulating material. A power semiconductor module according to any one of claims 1 to 4,
The power semiconductor module is characterized in that the hardness of the heat transfer sheet is smaller than the hardness of the first insulating material, and the hardness of the second insulating material is smaller than the hardness of the heat transfer sheet. . A power semiconductor module according to any one of claims 1 to 4,
2. The power semiconductor module according to claim 1, wherein a relative dielectric constant of the second insulating material is smaller than a relative dielectric constant of the first insulating material. A power semiconductor module according to any one of claims 1 to 4,
A power semiconductor module comprising a third insulating member for positioning the resin sealing body. A power semiconductor module according to any one of claims 1 to 4,
The power semiconductor module, wherein the resin sealing body has the insulating layers disposed on both surfaces of the circuit. The power semiconductor module according to claim 10, wherein
A metal case having an opening on one side and a recess on the other, and a cooler housed in the recess of the metal case,
The resin sealing body is accommodated in the opening of the metal case so as to be in contact with the metal case via the heat transfer sheet,
The power semiconductor module, wherein the cooler is disposed so as to sandwich the resin sealing body through the metal case. The power semiconductor module according to claim 11,
A power semiconductor module, wherein a heat transfer sheet is disposed between the cooler and the metal case. A power semiconductor module according to any one of claims 1 to 4, 10 to 12,
The circuit includes an upper arm side first power semiconductor element, a lower arm side second power semiconductor element, an upper arm side emitter circuit electrically connected to the first power semiconductor element, and the second arm side A lower arm side collector circuit electrically connected to the power semiconductor element,
The power semiconductor module, wherein the emitter circuit on the upper arm side and the collector circuit on the lower arm side are connected via an intermediate electrode.