JP2015053775A - Semiconductor power conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor power conversion device, with which it is possible to achieve miniaturization and an improvement in cooling efficiency.SOLUTION: According to an embodiment, a semiconductor power conversion device includes: a first conductor 61; a second conductor 63; a first semiconductor element that contains SiC and is formed like a plate, one of whose electrodes is joined to a first joint surface of the first conductor, and the other of whose electrodes is joined to a second joint surface of the second conductor; a second semiconductor element 51a one of whose electrodes is joined to the first joint surface of the first conductor and the other of whose electrodes is joined to the second joint surface of the second conductor; a heat radiation metal plate 67 that includes a flat heat reception surface 67a, on which a first and second bottom surfaces of the first and second conductors are mounted through a sheet-like insulator 66, and a flat heat radiation surface 67b that opposes the heat reception surface; and a cooler 80 that includes a cooling block 82 joined to the heat radiation surface of the heat radiation metal plate. The cooling block includes: a flat joint surface 82a that is in surface contact with the heat radiation surface; a rectangular recessed part 86 that includes a rectangular opening opened in the joint surface and forms a coolant passage through which a coolant flows while contacting the heat radiation surface; and a sealing material 92 provided to surround a periphery of the recessed part.

Description

  Embodiments described herein relate generally to a semiconductor power conversion device.

  In recent years, for the purpose of improving the fuel consumption of automobiles, the spread of hybrid cars using both an internal combustion engine and a motor is rapidly progressing. On the other hand, commercialization of electric vehicles that can run only with motors is also progressing. Generally, these automobiles include an inverter device as a semiconductor power conversion device that converts direct current into alternating current and supplies the motor to a motor. For example, a three-phase inverter device has three power semiconductor elements corresponding to the U phase, the V phase, and the W phase. Such an in-vehicle semiconductor power conversion device must be downsized, reduced in cost, and improved in cooling efficiency. In order to achieve this object, the power semiconductor element that is a main component of the semiconductor power conversion device is used. Miniaturization, cost reduction, and improvement in cooling efficiency are important.

  For example, according to the semiconductor power conversion device disclosed in Patent Document 1, the power semiconductor element is joined to the first conductor, the second conductor, and the third conductor, which are each formed of a conductive metal, and these conductors. And a heat dissipating metal plate having a joint surface. An IGBT (insulated gate bipolar transistor), which is a semiconductor element (chip) constituting the upper arm of one phase, and the positive electrode side of the diode are joined to the first conductor. The second conductor is joined to the IGBT constituting the lower arm of one phase and the negative electrode side of the diode. The third conductor is disposed between the first conductor and the second conductor, and is joined to the negative electrode side of the IGBT and the diode constituting the upper arm, and the positive electrode side of the IGBT and the diode constituting the lower arm. . The first conductor and the second conductor function as a positive electrode and a negative electrode, and the third conductor functions as an AC output electrode.

  And the 1st, 2nd, 3rd conductor is arrange | positioned at a cooler so that the joint surface with a semiconductor element may become non-parallel with the joint surface between the metal plate for heat dissipation, and a conductor. Furthermore, heat conduction grease is applied to the back surface of the heat radiating metal plate, and the heat radiating metal plate is fixed to the heat receiving plate of the cooler with screws or the like via the heat conduction grease. With such a configuration, a power semiconductor element and a semiconductor power conversion device with improved cooling efficiency and manufacturability are provided.

  Further, in recent years, power conversion devices are increasing in capacity, speed, and size as power semiconductor elements constituting power conversion devices are accelerating in response to market demands for reduction in size and cost. Power semiconductor elements tend to increase in heat flux, which is the amount of heat per unit area, because their external dimensions are reduced while capacity increases. On the other hand, it is difficult for the power semiconductor element to increase the allowable temperature of the semiconductor chip due to its characteristics, and therefore it is necessary to keep it within a certain temperature. For this reason, as the heat flux increases, there is an increasing demand for a cooler for semiconductor elements having excellent cooling efficiency. In particular, a cooler for a power converter for an electric vehicle or a hybrid car cools the joined power converter by flowing a coolant of pure water or antifreeze liquid through cooling fins provided on the flow path.

JP 2007-68302 A JP 2007-214281 A

  In the semiconductor power conversion device configured as described above, since the thermal conductive grease is applied between the power semiconductor element and the cooler, there is a thermal resistance corresponding to the thickness of the thermal conductive grease, thereby improving the cooling efficiency. It is an obstacle. In addition, fins that are enlarged heat transfer surfaces are arranged inside the cooler in order to lower the thermal resistance of the cooler, that is, to increase the cooling efficiency. The size of the cooler is increased by the height of the fin, and the material cost and manufacturing cost for forming the fin are also increased, which is an obstacle to miniaturization and cost reduction of the semiconductor power conversion device.

  The present invention has been made in view of the above points, and an object thereof is to provide a semiconductor power conversion device that can be further reduced in size and improved in cooling efficiency.

  According to the embodiment, the semiconductor power conversion device includes a first rectangular parallelepiped first conductor having a first joint surface and a first bottom surface orthogonal to the first joint surface, and a second facing the first joint surface in parallel. A rectangular parallelepiped second conductor having a second bottom surface orthogonal to the bonding surface and the second bonding surface and located in the same plane as the first bottom surface; and a first semiconductor element formed in a plate shape containing SiC. One electrode is bonded to the first bonding surface of the first conductor, and the other electrode is bonded to the second bonding surface of the second conductor, and is arranged in parallel with the first and second bonding surfaces. A first semiconductor element and a second semiconductor element formed in a plate shape, wherein one electrode is joined to the first joint surface of the first conductor and the other electrode is a second conductor of the second conductor. A second semiconductor element bonded to two bonding surfaces and disposed in parallel with the first and second bonding surfaces; A flat heat receiving surface on which the first and second bottom surfaces of the first and second conductors are placed via a sheet-like insulator, and a heat radiating metal plate having a flat heat radiating surface facing the heat receiving surface; And a cooler having a cooling block joined to the heat radiation surface of the metal plate for heat radiation. The cooling block has a flat joint surface that is in contact with the heat radiating surface of the heat radiating metal plate, and opens to the joint surface at a position facing the first and second conductors. A rectangular recess in which a flow path for flowing refrigerant is formed, and a sealing material that surrounds the periphery of the recess and is provided on the joint surface and is in close contact with the metal plate for heat.

FIG. 1 is a diagram illustrating an equivalent circuit of the semiconductor power conversion device according to the first embodiment. FIG. 2 is a plan view of a semiconductor module for one phase of the semiconductor power converter. FIG. 3 is an exploded perspective view of the semiconductor module. FIG. 4 is a cross-sectional view of the semiconductor module taken along line AA in FIG. FIG. 5 is a longitudinal sectional view of the semiconductor module taken along line BB in FIG. 2.

  Hereinafter, a semiconductor power conversion device according to an embodiment will be described in detail with reference to the drawings. Each figure is a schematic diagram for promoting an understanding of the embodiment and its shape, dimensions, ratio, etc. are different from the actual apparatus, but these are considered in consideration of the following description and known techniques. The design can be changed as appropriate.

(First embodiment)
FIG. 1 is an equivalent circuit diagram of the semiconductor power conversion device according to the first embodiment. As shown in FIG. 1, the semiconductor power conversion device 10 is configured as, for example, a U-phase, V-phase, and W-phase three-phase inverter, and is configured to supply power to the motor 12 as a load target.

  The semiconductor power converter 10 smoothes the DC power supplied to the power semiconductor module from the three power semiconductor modules 16, 18, and 20 corresponding to the U phase, V phase, and W phase, respectively, and the DC power source, for example, the battery 22. Applied to the smoothing capacitor 24, the current detectors 28a, 28b, 28c for detecting the current flowing to the motor 12 via the three-phase output connection conductor 26, and the current information detected by the current detector and the smoothing capacitor 24. The control unit 35 that controls the power semiconductor modules 16, 18, and 20 based on the voltage to be driven, and the drive for driving the gate of the semiconductor element (IGBT) of the power semiconductor module to be described later based on the control signal of the control unit 35 And a drive substrate 34 having a circuit. The driving substrate 34 is provided with driving ICs 36 for driving the semiconductor elements in a one-to-one correspondence with the semiconductor elements. That is, in this circuit, six driving ICs 36 are provided. Each power semiconductor module 16, 18, 20 is provided with a cooler described later for cooling them.

Hereinafter, the power semiconductor modules 16, 18, and 20 will be described in detail. Since the power semiconductor modules 16, 18, and 20 have the same configuration, one power semiconductor module 16 will be described as a representative.
2 is a plan view of the power semiconductor module 16, FIG. 3 is an exploded perspective view showing the power semiconductor module 16, FIG. 4 is a cross-sectional view of the power semiconductor module along line AA in FIG. 2, and FIG. FIG. 3 is a cross-sectional view of the power semiconductor module along the line BB in FIG. 2.

  As shown in FIGS. 1 to 4, in this embodiment, each power semiconductor module is a semiconductor having a so-called 2-in-1 structure in which two circuits in which IGBT elements and FWD (Free Wheeling Diode) elements are connected in parallel are combined into one package. Configured as a module. Each power semiconductor module is configured as a so-called double-sided heat dissipation type and vertical mounting type (vertical chip mount (VCM)) semiconductor module.

  More specifically, the power semiconductor module 16 includes a first semiconductor element constituting an upper arm of the U phase in the inverter circuit, here, an IGBT 41a as a first switching element and a diode (FWD (Free Wheeling) as a second semiconductor element. Diode)) 51a, the third semiconductor element constituting the lower arm of the U phase in the inverter circuit, here, the IGBT 41b functioning as the second switching element, the diode (FWD) 51b as the fourth semiconductor element, the first conductivity A body 61, a second conductor 62, a third conductor 63, an insulating resin sheet 66 as a sheet-like insulator, a heat radiating metal plate 67 functioning as a base, and a cover 70 covering these.

  The IGBTs 41a and 41b and the diodes 51a and 51b are, for example, plate-shaped semiconductor chips having a size of about 10 mm square, and each has electrodes on both sides. Each of the diodes 51a and 51b is connected in antiparallel to each of the IGBTs 41a and 41b. A plurality of input / output terminals 76a and 76b such as gate terminals are connected to each of the IGBTs 41a and 41b.

  The first, second, and third conductors 61, 62, and 63 are each formed of a conductive metal, for example, copper or aluminum, in the shape of an elongated rod having both ends in the axial direction, for example, a prismatic shape. The first conductor 61, the second conductor 62, and the third conductor 63 have the same length and are formed to have substantially the same diameter.

  One side surface of the first conductor 61 forms a first bonding surface 61a, and the other side surface orthogonal to the one side surface forms a first bottom surface 61b. The first joint surface 61a of the first conductor 61 is electrically and mechanically joined to the IGBT 41a and the positive electrode side (collector and cathode, respectively) constituting the upper arm via the thermal shock plate 30. The first conductor 61 constitutes a DC positive conductor common to the first and second semiconductor elements. On the first bonding surface 61 a, the IGBT 41 a and the diode 51 a are arranged side by side along the longitudinal direction (center axis direction) of the first conductor 61.

  One side surface of the second conductor 62 forms a second bonding surface 62a, and the other side surface orthogonal to the one side surface forms a second bottom surface 62b. The second bonding surface 62a of the second conductor 62 is bonded to the negative electrode (emitter and anode) electrodes of the IGBT 41b and the diode 51b constituting the lower arm via the thermal shock plate 31, respectively. Thereby, the 2nd conductor 62 is electrically and mechanically connected with the electrode of the negative electrode side of IGBT41b and the diode 51b. The second conductor 62 constitutes a DC negative conductor common to the third and fourth semiconductor elements. On the second bonding surface 62 a, the IGBT 41 b and the diode 51 b are arranged side by side along the longitudinal direction (center axis direction) of the second conductor 62.

  The second conductor 62 is arranged in parallel with the first conductor 61 with a gap therebetween. The first bonding surface 61a of the first conductor 61 and the second bonding surface 62a of the second conductor 62 face each other in parallel with a gap. The first bottom surface 61b of the first conductor 61 and the second bottom surface 62b of the second conductor 62 are located side by side on the same plane.

  The third conductor 63 is disposed in parallel with the first and second conductors with a gap between the first conductor 61 and the second conductor 62. The third conductor 63 is arranged such that one end in the axial direction thereof is aligned with one end in the axial direction of the first and second conductors 61 and 62. The third conductor 63 is arranged such that the other axial end portion thereof is aligned with the other axial end portions of the first and second conductors 61 and 62. The third conductor 63 has a central axis along the longitudinal direction thereof, and the first, second, and third conductors 61, 62, and 63 are disposed symmetrically with respect to the central axis.

  Two opposing side surfaces of the third conductor 63 form two third joint surfaces 63 a, and these first joint surfaces 63 a are formed on the first joint surface 61 a of the first conductor 61 and the second conductor 62. The second joint surfaces 62a face each other in parallel. The other side surface of the third conductor 63 that is orthogonal to the two third joint surfaces 63a forms a third bottom surface 63b. The third bottom surface 63b is located in the same plane as the first bottom surface 61b and the second bottom surface 62b of the first and second conductors 61 and 62.

  One joining surface 63a of the third conductor 63 is joined to the negative electrode (emitter and anode respectively) electrodes of the IGBT 41a and the diode 51a constituting the upper arm via the thermal shock plate 32. Thereby, the 3rd conductor 63 is electrically and mechanically connected with the electrode of the negative electrode side of IGBT41a and the diode 51a. The other third joint surface 63a of the third conductor 63 is joined via the thermal shock plate 33 to the IGBT 41b and the positive electrode (collector and cathode) electrodes of the diode 51b constituting the lower arm. Thereby, the 3rd conductor 63 is electrically and mechanically connected with the electrode of the positive electrode side of IGBT41b and the diode 51b. The third conductor 63 constitutes an AC electrode conductor (electrode conductor).

  The IGBT 41a is disposed at a position shifted in the direction along the central axis of the third conductor 63 with respect to the IGBT 41b, and is disposed facing the diode 51b without facing the IGBT 41b. Similarly, the IGBT 41b is disposed to face the diode 51a.

  It should be noted that the bonding surface of each conductor described above, and the IGBT and the diode can be bonded by solder or a conductive adhesive, or may be bonded via a thermal shock plate. The material of the first, second, and third conductors 61, 62, and 63 is preferably copper from the viewpoint of cooling, but may be a metal other than aluminum or a metal composite material such as Al—SiC.

  As shown in FIGS. 2 to 5, the heat radiating metal plate 67 is formed in a rectangular shape, the upper surface thereof forms a flat heat receiving surface 67a, and the lower surface (bottom surface) opposite to the flat heat receiving surface 67b. Is forming. The heat radiating metal plate 67 has an area sufficiently larger than the entire first to third conductors 61, 62, 63. In addition, through holes 72 for inserting screws are formed in the four corners of the heat radiating metal plate 67 and the central part of each long side edge.

  The heat receiving surface 67a of the heat radiating metal plate 67 has first, second, and third bottom surfaces 61b, 62b, 63b of the first conductor 61, the second conductor 62, and the third conductor 63 through the insulating resin sheet 66. To support these conductors. The heat radiating metal plate 67 functioning as a heat radiating member is formed of, for example, a metal having high heat conductivity such as copper or aluminum, receives heat from the IGBT, the diode, and the first to third conductors, and external and external coolers described later. To dissipate heat.

  The insulating resin sheet 66 is formed of a material having sufficiently low rigidity with respect to the first to third conductors, for example, an epoxy resin having adhesiveness filled with a ceramic filler such as boron nitride. As shown in FIG. 4, the width W3 of the insulating resin sheet 66 is the total width of the first, second, and third conductors 61, 62, and 63, that is, orthogonal to the first, second, and third joint surfaces. The width W2 is slightly larger than the width W2 in the direction in which the refrigerant flows, and is smaller than the width W1 of the refrigerant flow path of the cooler described later. Further, as shown in FIG. 5, the length of the insulating resin sheet 66 is slightly larger than the lengths of the first, second, and third conductors 61, 62, and 63, and is less than the length of the refrigerant flow path. Is formed.

The upper surface of the heat radiating metal plate 67 joined to the first, second, and third conductors 61, 62, 63, that is, the heat receiving surface 67 a is the first joining surface 61 a of the first conductor 61, the second conductor. 62 extends in a direction intersecting the second joint surface 62a of the second conductor 62 and the third joint surface 63a of the third conductor 63, for example, in a direction orthogonal thereto. That is, the semiconductor elements of the IGBT and the diode are arranged so that the positive electrode side and the negative electrode side surface thereof are not parallel to the heat receiving surface 67 a of the heat radiating metal plate 67.
As shown in FIGS. 2 and 3, the positive electrode output terminal 74 is connected to one end of the first conductor 61 in the axial direction, and extends in one direction from the first conductor. A negative electrode output terminal 75 is connected to one end of the second conductor 62 in the axial direction, and extends from one end of the second conductor in the same direction as the positive electrode output terminal 74. An AC output terminal 77 is connected to the other axial end of the third conductor 63, that is, the other end located on the opposite side of the positive output terminal 74, and is opposite to the positive output terminal 74 from the other end of the third conductor. It extends in the direction of.

  As shown in FIGS. 2, 4 and 5, the first to third conductors 61, 62, 63 and the first to fourth semiconductor elements are covered with a cover 70 formed of synthetic resin or the like. . The cover 70 is fixed to a later-described cooling block together with the heat radiating metal plate 67 by a plurality of, for example, six fixing screws 78. The respective ends of the positive electrode output terminal 74, the negative electrode output terminal 75, and the AC output terminal 77 are provided exposed on the outer surface of the cover. Further, the input / output terminals 76a and 76b of the IGBTs 41a and 41b penetrate the cover 70 and protrude upward.

  As shown in FIGS. 2 to 5, the heat radiation metal plate 67 of the semiconductor module 16 configured as described above is directly attached to the cooler 80, and the semiconductor module 16 and the cooler are integrated. Specifically, the cooler 80 includes a flat rectangular parallelepiped cooling block 82 made of, for example, aluminum. The cooling block 82 has a flat rectangular joint surface 82 a, and the joint surface 82 a is formed in a larger area than the heat radiating metal plate 67. Screw holes 83 are respectively formed at the four corners of the joint surface 82a and the center of each long side edge. The heat dissipating metal plate 67 is placed on the cooling block 82 with its heat dissipating surface 67 b in contact with the joint surface 82 a of the cooling block 82, and six fixing screws 78 are inserted into the through holes of the heat dissipating metal plate 67. 72 is fixed to the cooling block 82 by being screwed into the screw holes 83 of the cooling block 82.

  The cooling block 82 has a rectangular recess 86 that opens to the joint surface 82 a and forms a coolant channel 84. The depth of the recess 86, that is, the height of the coolant channel 84 is, for example, 5 mm. The recess 86 has a rectangular opening 86 a that faces the first, second, and third conductors of the semiconductor module 16, and the refrigerant 95 in the refrigerant flow path 84 is a heat radiation surface 67 b of the metal plate 67 for heat radiation. It flows directly in contact with. An inflow pipe 88 a is attached to one end in the longitudinal direction of the cooling block 82 and communicates with the refrigerant flow path 84. An outflow pipe 88 b is attached to the other end in the longitudinal direction of the cooling block 82 and communicates with the refrigerant flow path 84. As shown in FIG. 5, the outflow pipe 88b is connected to the condenser 89 and the pump 91 through a pipe, and the pump 91 is further connected to the inflow pipe 88a through the pipe. The refrigerant flow path 84 and the piping of the cooling block 82 are filled with the refrigerant 95. Then, by circulating the refrigerant by the pump 91, the refrigerant 95 flows through the inflow pipe 88a, the refrigerant flow path 84 and the outflow pipe 88b in the cooling block 82, and further cooled by the condenser 89, and then again. Return to pump 91. The refrigerant 95 flows in direct contact with the heat radiating surface 67 b of the heat radiating metal plate 67 in the refrigerant flow path 84.

  As shown in FIG. 4, the width W1 of the coolant channel 84 along the direction orthogonal to the first to third joint surfaces 61a, 61b, 61c of the first to third conductors 61, 62, 63 is an insulating resin. The sheet 66 is formed to have a width equal to or greater than the width W3 of the sheet 66. Further, when the thickness of the metal plate for heat dissipation is t and the total width of the first to third conductors along the direction orthogonal to the first to third joint surfaces 61a, 62a, 63a is W2, The width W1 of the path 84 is formed as W2 + 2t, and the first to third conductors 61, 62, 63 are within the range of the width of the opening 86a of the recess 86, that is, within the range of the width W1 of the refrigerant flow path 84. , Is installed.

  As shown in FIGS. 2 to 5, the cooling block 82 has an annular engagement groove 90 formed on the joint surface 82 a so as to surround the opening 86 a of the recess 86, that is, the refrigerant flow path 84. In the engagement groove 90, for example, an annular gasket or an O-ring 92 is mounted as a seal material. The gasket or O-ring 92 is in close contact with the heat radiating surface 67b of the heat radiating metal plate 67 and seals the periphery of the refrigerant flow path 84 to prevent the refrigerant from leaking. In addition, each screwing position of the metal plate 67 for heat dissipation by the fixing screw 78 is located on the outer side (outer peripheral side) of the sealing material. The sealing material is not limited to a gasket and an O-ring, and an adhesive or the like may be used.

  With the above configuration, the power semiconductor module 16 for the U phase is obtained. The V-phase power semiconductor module 18 and the W-phase power semiconductor module 20 are configured in the same manner as the U-phase power semiconductor module 16 described above.

  According to the semiconductor power conversion device 10 configured as described above, in each semiconductor module, since the temperature of the heat radiating metal plate 67 is equal to or higher than the boiling point of the refrigerant 95, the refrigerant in contact with the heat radiating surface 67b of the heat radiating metal plate 67. The liquid layer portion 95 reaches the saturation temperature, and bubbles 93 are generated on the heat radiating surface 67b, resulting in boiling. The saturation temperature indicates a temperature at which the temperature gradually increases as the liquid is heated, and eventually the liquid temperature does not increase any further. When the liquid is further heated, liquid vaporization occurs inside the liquid. This state is the boiling point, and the saturation temperature is called the boiling point.

  The refrigerant 95 flowing into the refrigerant flow path 84 is at a temperature lower than the saturation temperature, and is supplied to the refrigerant flow path 84, bubbles are generated only in the liquid layer portion near the heat radiating metal plate 67, and boiling occurs. At a location away from the heat radiating metal plate 67 to some extent, the refrigerant 95 is at a temperature lower than the saturation temperature, and boiling does not occur. Bubbles 93 generated from the heat radiating surface 67 b of the heat radiating metal plate 67 are discharged out of the cooler 80 by the flowing refrigerant 95, condensed by the condenser 89 provided outside, and supplied to the refrigerant flow path 84 by the pump 91. Is done.

  With the above-described configuration, the heat loss generated in the IGBTs 41a and 41b is thermally conducted to the heat radiating metal plate 67 through the first, second, and third conductors 61, 62, and 63 and the insulating resin sheet 66. Boiling heat is transferred from the metal plate 67 to the refrigerant 95 to be radiated. Thereby, both sides of IGBT41a, 41b are cooled.

As described above, on the heat radiating surface 67b of the heat radiating metal plate 67, boiling occurs due to the transfer of heat when the refrigerant 95 having extremely large heat energy is vaporized, so that heat loss from the heat radiating metal plate 67 to the refrigerant 95 occurs. The heat transfer coefficient, which is a coefficient for transferring heat, becomes very large, and the value thereof is 4500 W / m ² K or more.

On the other hand, in the conventional cooler, the heat transfer rate is about 1500 W / m ² K due to the restriction of the flow rate due to the capacity of the pump. Further, the area expansion rate of the heat radiating part by the fin is about three times as much as the outer shape and the fin efficiency, and the heat transfer rate between the heat radiating part and the refrigerant is about 4500 W / m ² K.

  From the above, in this embodiment, although the heat dissipation surface of the heat radiating metal plate 67 is a smooth surface, that is, although it does not have fins, the heat transfer coefficient is equal to or higher than the conventional one. Since there is no structure like a fin, the cooler can be reduced in size and cost.

  For example, when the refrigerant 95 is pure water, the inflow temperature of the refrigerant 95 into the refrigerant flow path 84 is 100 ° C. or less at atmospheric pressure, but the liquid layer portion near the heat radiating metal plate 67 has a water saturation temperature. It becomes 100 degreeC which is. Although depending on the heat loss of the IGBTs 41a and 41b, when the heat radiating metal plate 67 is about 120 to 130 ° C, the operating temperature of the IGBTs 41a and 41b is increased to 150 to 175 ° C or higher. For this reason, the material of the IGBTs 41a and 41b is preferably SiC or the like capable of high temperature difference.

  With the above-described configuration, the heat radiation metal plate 67 of the semiconductor module is directly cooled by the refrigerant 95, so that the conventional heat conduction grease is unnecessary, and the heat resistance is reduced by the absence of the heat conduction grease. Cooling efficiency is improved. Furthermore, the thickness of the cooler 80 can be reduced by an amount corresponding to no fins, and the entire semiconductor module can be reduced in size and thickness.

  The IGBT is cooled on both sides by joining both electrodes to conductors on both sides. Therefore, the semiconductor module has a cooling capability equivalent to that of the conventional power conversion device, and the thermal resistance is reduced and the cooling efficiency is improved by the absence of the thermal conductive grease. The thermal resistance of the IGBT and the diode chip inside the power semiconductor device is further reduced, the temperature rise of the IGBT and the diode chip is reduced, and the cooling efficiency is improved. Furthermore, the cooler can be downsized, and the cooling efficiency of the semiconductor power converter can be improved, downsized, and reduced in cost.

  From the above, according to the present embodiment, it is possible to provide a power semiconductor power conversion device that can be further reduced in size and improved in cooling efficiency.

The present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.
For example, the dimensions, shapes, materials, and the like of the constituent members of the power semiconductor device are not limited to the above-described embodiments, and can be variously changed according to the design. The number of semiconductor modules installed, the ratio of the number of installations, and the ratio of the flow path widths are not limited to the embodiment and can be changed as necessary.

  In the above-described embodiment, a so-called 2-in-1 semiconductor module is used. However, the first and second conductors and the first and second conductors sandwiched between the conductors are not limited to this. It may be a so-called 1 in 1 semiconductor module having a semiconductor element.

DESCRIPTION OF SYMBOLS 10 ... Semiconductor power converter device, 12 ... Motor, 12 ... 1st inverter,
16, 18, 20 ... semiconductor module, 41a, 41b ... IGBT,
51a, 51b ... FWD element, 61 ... first conductor, 62 ... second conductor,
63 ... 3rd conductor, 61a ... 1st joining surface, 62a ... 2nd joining surface,
63a ... third joint surface, 61b ... first bottom surface, 62b ... second bottom surface, 63b ... third bottom surface,
67 ... Metal plate for heat dissipation, 67a ... Heat receiving surface, 67b ... Heat dissipation surface, 80 ... Cooler,
82 ... Cooling block, 82a ... Joint surface, 84 ... Refrigerant flow path, 86 ... Recess,

Claims (5)

A rectangular parallelepiped first conductor having a first joint surface and a first bottom surface orthogonal to the first joint surface;
A rectangular parallelepiped second conductor having a second joint surface facing in parallel with the first joint surface and a second bottom surface orthogonal to the second joint surface and located in the same plane as the first bottom surface;
A first semiconductor element including SiC and formed in a plate shape, wherein one electrode is bonded to a first bonding surface of the first conductor and the other electrode is bonded to a second bonding surface of the second conductor. A first semiconductor element bonded and disposed parallel to the first and second bonding surfaces;
A second semiconductor element formed in a plate shape, wherein one electrode is bonded to the first bonding surface of the first conductor, and the other electrode is bonded to the second bonding surface of the second conductor, A second semiconductor element disposed in parallel with the first and second bonding surfaces;
A flat heat receiving surface on which the first and second bottom surfaces of the first and second conductors are placed via a sheet-like insulator, and a heat radiating metal plate having a flat heat radiating surface facing the heat receiving surface; ,
A cooler having a cooling block joined to the heat radiation surface of the metal plate for heat radiation,
The cooling block has a flat joint surface that is in contact with the heat radiating surface of the heat radiating metal plate, and opens to the joint surface at a position facing the first and second conductors. A semiconductor power comprising: a rectangular recess in which a flow path for flowing refrigerant is formed; and a sealing material that surrounds the periphery of the recess and is provided on the joint surface and is in close contact with the metal plate for heat. Conversion device.   The width of the sheet-like insulator is larger than the width of the first and second conductors in the direction orthogonal to the first and second joint surfaces, and the width of the coolant channel formed by the recess. The semiconductor power conversion device according to claim 1 formed as follows.   When the thickness of the metal plate for heat dissipation is t, and the total width of the first and second conductors along the direction orthogonal to the first and second joint surfaces is W2, the opening of the recess is 3. The semiconductor power conversion device according to claim 1, wherein a width is formed to be W2 + 2t, and the first and second conductors are installed within a range of the width of the opening.   The cooling block has an annular engagement groove provided on the joint surface surrounding the periphery of the recess, and the sealing material has an annular O-ring or gasket attached to the engagement groove. The semiconductor power converter device of any one of Claim 1 thru | or 3. A third joint surface disposed between the first conductor and the second conductor and facing in parallel to the first joint surface of the first conductor and in parallel with the second joint surface of the second conductor. A third conductor having a third bottom surface opposite to the third joint surface, and a third bottom surface orthogonal to the third joint surface and positioned in the same plane as the first bottom surface;
A third semiconductor element including SiC and formed in a plate shape, wherein one electrode is bonded to the third bonding surface of the third conductor and the other electrode is bonded to the second bonding surface of the second conductor. A third semiconductor element disposed parallel to the second and third bonding surfaces;
A fourth semiconductor element formed in a plate shape, wherein one electrode is bonded to the third bonding surface of the third conductor, and the other electrode is bonded to the second bonding surface of the second conductor; A fourth semiconductor element disposed in parallel with the second and third bonding surfaces,
In the first semiconductor element, one electrode is bonded to the first bonding surface of the first conductor, and the other electrode is bonded to the third bonding surface of the third conductor,
In the second semiconductor element, one electrode is bonded to the first bonding surface of the first conductor, and the other electrode is bonded to the third bonding surface of the third conductor,
The first, second, or third bottom surface of each of the first, second, and third conductors is fixed to the heat receiving surface of the heat radiating metal plate via the sheet-like insulator. A semiconductor power conversion device according to claim 1.

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