Power conversion device and manufacturing process for a power conversion device

Abstract

A power conversion device comprises: a semiconductor element; a heat exchanger plate connected to the semiconductor element; a semiconductor module formed by shaping the semiconductor element and the heat exchanger plate with resin; a thermally conductive material in a semi-solid form arranged in contact with the heat exchanger plate and covering a surface of the semiconductor module; and a heat dissipation element that dissipates heat from the semiconductor module through the thermally conductive material.

Description

Technical area

[0001] The present invention relates to a power conversion device and a manufacturing method for a power conversion device. State of the art

[0002] In a power conversion device with a double-sided cooling structure, a thermally conductive material, such as a thermal interface material (TIM), is interposed between the power conversion device and a cooling water channel, which is a heat dissipation element. Depending on the contact situation between this thermally conductive material and a lead frame (heat exchanger plate) included in a semiconductor module, the reliability of the device may deteriorate. The power conversion device is also required to reduce costs and improve productivity.

[0003] PTL 1 described below discloses a device having a structure in which heat generated in a semiconductor element is efficiently dissipated to the outside by providing a heat transfer layer on an upper surface of the semiconductor element. Citation listPatent literature

[0004] PTL 1: JP No. 5740995 Summary of the inventionTechnical problem

[0005] The structure described in PTL 1 has a possibility of pumping out a TIM, which is a heat transfer layer (thermally conductive material), and this leads to a problem of increasing thermal resistance or deteriorating insulation quality. In view of this, an object of the present invention is to provide a power conversion device and a manufacturing method for the power conversion device that achieve cost reduction, productivity improvement, and reliability improvement. Solution to the problem

[0006] A power conversion device includes: a semiconductor element; a heat exchanger plate connected to the semiconductor element; a semiconductor module formed by molding the semiconductor element and the heat exchanger plate with resin; a heat-conductive material having a semi-solid shape disposed in contact with the heat exchanger plate and covering a surface of the semiconductor module; and a heat dissipation member that dissipates heat from the semiconductor module through the heat-conductive material.

[0007] As a manufacturing method for a power conversion device, a method is employed, the method comprising: forming a semiconductor module by molding, including a resin, a semiconductor element, and a heat exchanger plate bonded to the semiconductor element; forming a stepped portion formed to expose a surface of the heat exchanger plate and surrounding the surface of the heat exchanger plate by removing a part of a molding resin from a surface of the semiconductor module that has been formed; and mounting, on the semiconductor module, a heat-conductive material having a semi-rigid shape that is disposed in contact with an exposed surface of the heat exchanger plate and covers the molding resin on the one surface, and a heat dissipation member that dissipates heat from the semiconductor module via the heat-conductive material. Advantageous effects of the invention

[0008] It is possible to provide a power conversion device and a manufacturing method for the power conversion device that achieve cost reduction, improvement in productivity, and improvement in reliability. Short description of the drawings [ Fig. 1] Fig. 1 is a circuit diagram of a power conversion device. [ Fig. 2] Fig. 2 is an overall view of the power conversion device. [ Fig. 3] Fig. 3 is a cross-sectional view of a power conversion device according to an embodiment of the present invention. [ Fig. 4] Fig. 4 is a view describing a first manufacturing method for the power conversion device. [ Fig. 5] Fig. 5 is a view describing a second manufacturing method for the power conversion device. [ Fig. 6] Fig. 6 is a view describing a positional relationship between a first thermally conductive material and a semiconductor module. [ Fig. 7] Fig. 7 is a view describing a positional relationship between a second thermally conductive material and a semiconductor module.

[0009] An embodiment of the present invention will be described below with reference to the drawings. The following description and drawings are examples for describing the present invention and are omitted and simplified for clarity. The present invention may be embodied in various other forms. Unless otherwise stated, each constituent element may be singular or plural.

[0010] The positions, sizes, shapes, areas, and the like of the constituent elements illustrated in the drawings do not always represent actual positions, sizes, shapes, areas, and the like in order to facilitate easy understanding of the invention. Therefore, the present invention is not necessarily limited to the positions, sizes, shapes, areas, and the like disclosed in the drawings. (An embodiment of the present invention and overall configuration) (FIG. 1)

[0011] In a power conversion device 100, each of a plurality of circuit bodies 1 constituting a power conversion circuit is formed by a semiconductor element such as an insulated gate bipolar transistor (IGBT) or a metal oxide semiconductor field-effect transistor (MOSFET). Two circuit bodies 1 connected in series and a capacitor 2 are paired to form a single-phase power conversion circuit. A three-phase power conversion circuit is connected to a positive electrode wire 3 and a negative electrode wire 4, respectively.

[0012] The circuit body 1 (semiconductor module 1) has three terminals of a high-voltage side main circuit terminal (collector terminal for IGBT and drain terminal for MOSFET), a low-voltage side main circuit terminal (emitter terminal for IGBT and source terminal for MOSFET) and a control terminal (gate terminal). (FIG. 2)

[0013] The power conversion device 100 includes the plurality of circuit bodies 1, each having a plurality of power semiconductor elements, a circuit board 6 (hereinafter, circuit board 6) electrically connected to the circuit bodies 1 and provided with a plurality of positive electrode wires 3 and a plurality of negative electrode wires 4 stacked on each other in a thickness direction, and a plurality of smoothing capacitors 2 each provided corresponding to the plurality of circuit bodies 1. The positive electrode wires 3 and the negative electrode wires 4 are in a thickness direction of the circuit board 6 (forward-backward direction of the film of Fig. 2) stacked on top of each other and connect the capacitor 2 of each phase and the circuit body 1 (details will be given later with reference to Fig. 4 to Fig. 7).

[0014] Fig. 2 illustrates a configuration example of circuits for three phases provided on the circuit board 6, where eight circuit bodies 1 are a one-phase circuit in which the circuit bodies 1 are arranged in groups of four in parallel and are arranged to face each other via the positive electrode wire 3 and the negative electrode wire 4. In this way, the circuit bodies 1 can be arranged in a plurality of parallel connections according to a desired output current value. Similarly, to satisfy a capacitor capacity determined depending on a desired input voltage fluctuation amount, the capacitors 2 on the circuit board 6 can be connected in a plurality of parallel connections.

[0015] The circuit board 6 has a plurality of conductor layers in the thickness direction, and each conductor layer is stacked via a resin layer. The conductor layer of the circuit board 6 has the positive electrode wire 3, the negative electrode wire 4, an output wire 7, and a signal wire 9 formed therein. The circuit body 1 and the capacitor 2 are connected to the positive electrode wire 3 and the negative electrode wire 4 by a bonding material such as solder. The circuit body 1 has a signal terminal 8 for connecting to the signal wire 9. Each of the positive electrode wire 3, the negative electrode wire 4, and the output wire 7 is formed thicker than the signal wire 9 connected to the circuit body 1, and has a configuration corresponding to the current to be supplied to a load of a connection destination being larger than that in other wires.

[0016] The positive electrode wire 3 and the negative electrode wire 4 have a via 5 (hereinafter, via 5). The via 5 is provided in a region where the positive electrode wires 3 and the negative electrode wires 4 of each phase are not stacked on top of each other. Each of the plurality of positive electrode wires 3 or the plurality of negative electrode wires 4 penetrates in the thickness direction of the board 6 to form the via 5, whereby wires having the same potential are electrically connected to each other. This suppresses a decrease in the cross-sectional area of ​​the positive electrode wire 3 and the negative electrode wire 4 in a region not provided with the via 5 and suppresses the positive electrode wire 3 and the negative electrode wire 4 from being divided in a region provided with the via 5.

[0017] It should be noted that when using a blind via for via 5, by removing the first layer and the second layer from the top surface (the surface on the front side in Fig. 2) the circuit board 6 formed of four layers as the positive electrode wire 3 and the third layer and the fourth layer as the negative electrode wire 4, it is possible to stack the positive electrode wires 3 and the negative electrode wires 4 without reducing the cross-sectional areas of the positive electrode wire 3 and the negative electrode wire 4.

[0018] The positive electrode wire 3 is connected to a positive electrode terminal of a DC voltage source, such as a battery (not shown), and the negative electrode wire 4 is connected to a negative electrode terminal of a DC voltage source, such as a battery (not shown). As a result, a DC voltage is supplied to the circuit of each phase.

[0019] The capacitors 2 are connected side by side along the circuit board 6 to satisfy a capacitor capacity determined depending on a desired input voltage fluctuation amount, and include a positive electrode terminal 10 and a negative electrode terminal 11 as terminals for connecting to the positive electrode wire 3 and the negative electrode wire 4 of the circuit board 6.

[0020] The positive electrode terminal 10 of the capacitor 2 is electrically connected to the high-voltage side main circuit terminal of the circuit body 1 on the high-voltage side (upper arm) by connecting to the positive electrode wire 3. The positive electrode wire 3 is connected to the positive electrode terminal 10 of the capacitor 2 of the other phase and a high-voltage side main circuit terminal of the circuit body 1 on the high-voltage side of the other phase. The negative electrode terminal 11 of the capacitor 2 is connected to the low-voltage side main circuit terminal of the circuit body 1 on the low-side (lower arm) by connecting to the negative electrode wire 4. The negative electrode wire 4 is connected to the negative electrode terminal 11 of the capacitor 2 of the other phase and a low-voltage side main circuit terminal 12 of the circuit body 1 on the low-side of the other phase.The low-voltage side main circuit terminal of the high-voltage side circuit body 1 is connected to the high-voltage side main circuit terminal of the low-voltage side circuit body 1 through the output wire 7 of each phase. The output wire 7 of each phase is connected to a load such as a motor (not shown).

[0021] The control terminal of the circuit body 1 is connected to a control circuit (not shown) and is turned on or off based on a signal input from a high-order control device such as a microcomputer, thereby outputting an AC voltage to a load such as a motor. (FIG. 3)

[0022] Fig. 3 is a cross-sectional view illustrating the configuration of the circuit body 1 (hereinafter, semiconductor module 1). The semiconductor module 1 includes a semiconductor element 23 and a heat exchanger plate 20 (lead frame 20). The semiconductor element 23 and the heat exchanger plate 20 are molded by a resin 24 (resin). The semiconductor element 23 is connected to the heat exchanger plate 20 via solder on both chip surfaces. Note that the connection between the semiconductor element 23 and the heat exchanger plate 20 is not limited to solder, and a sintered material, a hybrid material of metal and resin, or the like may be used. A gate pad (not shown) on the upper chip surface of the semiconductor element 23 and a lead terminal 12 are connected by wire bonding 13.

[0023] The supply connection 12, which protrudes outward from the heat exchanger plate 20, is connected to the plate 6 by solder. In the heat exchanger plate 20, the heat exchanger plate 20 (source side) is on the upper side in Fig. 3 a first heat exchanger plate 20a, and the lower side is a second heat exchanger plate 20b.

[0024] Two thermally conductive materials 21a and 21b are arranged on the upper surface of the first heat exchanger plate 20a. The thermally conductive materials 21a and 21b are, for example, TIMs. The thermally conductive materials 21a and 21b are semi-rigid thermally conductive materials arranged in contact with the first heat exchanger plate 20a and covering a surface of the semiconductor module 1. Note that the semi-rigid thermally conductive material refers to a thermally conductive material made of a material such as a filler or grease, which is deformed in shape by pressing.

[0025] The thermally conductive materials 21a and 21b are in contact with an insulating film 22 on a surface (surface of the second thermally conductive material 21b) opposite to a surface (surface of the first thermally conductive material 21a) in contact with the heat exchanger plate 20a. The insulating film 22 is in contact with a first cooling water channel 26a on a surface opposite to a surface in contact with the second thermally conductive material 21b. With such a structure, heat generated from the semiconductor module 1 is dissipated through the first cooling water channel 26a, which is a heat dissipation member, via the thermally conductive materials 21a and 21b.

[0026] This semiconductor module 1 has a stepped portion 24a formed to surround the periphery of the first thermally conductive material 21a on a surface (upper surface side) in contact with the thermally conductive materials 21a and 21b. The stepped portion 24a is formed by processing a part of the molding resin 24 at an upper surface end portion of the semiconductor module 1. The stepped portion 24a has, in the cross-sectional view of Fig. 3 has two protrusion shapes. Of the thermally conductive materials 21a and 21b, the first thermally conductive material 21a is disposed on the inner side of the stepped portion 24a, whereby the first thermally conductive material 21a is disposed so that its periphery is surrounded by the stepped portion 24a. On the other hand, the second thermally conductive material 21b has an area larger than that of the first thermally conductive material 21a. Note that, from the viewpoint of mold releasability, when the protrusion portion of the stepped portion 24a is formed by punching, the draft angle of the punch is desirably 3 degrees or more.

[0027] The height of the semiconductor module 1, which includes the heat exchanger plate 20 to which the chip of the semiconductor element 23 is soldered, varies within a range of less than 100 μm as a result of experiments and research. Therefore, from the viewpoint of thermal resistance and material cost, the thickness of the first thermally conductive material 21a is desirably 100 μm or less. The second thermally conductive material 21b can reduce thermal resistance as thin as possible from the viewpoint of pumping out, but at the same time, it is also necessary to absorb variations in the height of the upper surface of the stepped portion 24a of the semiconductor module 1 mounted on the circuit board 6. Therefore, the thickness of the second thermally conductive material 21b is desirably 100 μm or less.

[0028] The semiconductor module 1 is in contact with a third heat-conducting material 21c via the heat exchanger plate 20b on a surface which is lower (lower side in Fig. 3) than the circuit board 6. The circuit board 6 is in contact with a heat dissipation film 25 on the lower surface of Fig. 3. The heat dissipation sheet 25 is in contact with a second cooling water channel 26b on a surface opposite to the surface in contact with the circuit board 6. With such a structure, both surfaces of the semiconductor module 1 are covered with the heat-conducting materials 21a, 21b, and 21c, and heat generated from the semiconductor module 1 and the circuit board 6 is dissipated through the cooling water channels 26a and 26b arranged by sandwiching the semiconductor module 1 from both surfaces.

[0029] Note that the first thermally conductive material 21a and the second thermally conductive material 21b, which are two thermally conductive materials, may be integrated and arranged on a surface of the semiconductor module 1 as one thermally conductive material 21. (First manufacturing method for a power conversion device) (FIG. 4)

[0030] Fig. 4(a) is a view illustrating an example of a first manufacturing method, and Fig. 4(b) is a view after the resin mold is inserted into the die of Fig. 4(a) flows and is cured. The semiconductor element 23 is connected to the first heat exchanger plate 20a by soldering, and the semiconductor element 23 and the lead terminal 12 are subjected to wire bonding 13. Further, the first thermally conductive material 21a having a semi-rigid shape is arranged in contact with the first heat exchanger plate 20a between a frame of a die 28 and the first heat exchanger plate 20a. As described above, after the heat exchanger plates 20a and 20b, the semiconductor element 23, and the first thermally conductive material 21a are inserted into the die 28, transfer molding with the resin 24 is performed. This can form the semiconductor module 1 including the stepped portion 24a on one surface and having the surface of the first heat exchanger plate 20a exposed.

[0031] In this way, since the first thermally conductive material 21a is inserted into the die 28 in a state where it is arranged before resin molding, it is possible to prevent overmolding in which no gap is generated between the first heat exchanger plate 20a and the die 28 and the thermal resistance increases. Grinding and cleaning processes performed to eliminate overmolding caused by a state where the first thermally conductive material 21a is not arranged before resin molding are simplified. Metal pieces and residues remain after cleaning, and it is possible to prevent deterioration of the insulation quality and peeling of the first thermally conductive material 21a.In this way, according to the manufacturing method of the present invention, it is possible to provide the semiconductor module 1 in a state where an electrode surface of the heat exchanger plate 20 is exposed at a stage where the resin molding is completed.

[0032] The semiconductor module 1 manufactured by this manufacturing method is mounted on the circuit board 6, the second thermally conductive material 21b is further brought into contact with the upper surface (one surface) of the semiconductor module 1, the third thermally conductive material 21c is brought into contact with the lower surface (the other surface), each is fixed with the insulation film 22, and finally, the semiconductor module 1 is sandwiched from above and below by the cooling water channels 26a and 26b. Due to this, the power conversion device 100 is completed.

[0033] Conventionally, when the semiconductor module 1 without a stepped portion 24a is formed after resin molding, there has been a problem that the thermal resistance increases due to the occurrence of pumping out or the generation of voids. However, by assembling the semiconductor module 1 by the manufacturing method of the present invention, the first thermally conductive material 21a is sandwiched with the stepped portions 24a, and the second thermally conductive material 21b is disposed on the upper surface thereof, and therefore, the pumping out of the second thermally conductive material 21b can be suppressed. (Second manufacturing method for a power conversion device) (FIG. 5)

[0034] Fig. 5(a) to Fig. 5(c) are views describing a second manufacturing process. First, in Fig. 5(a), the semiconductor element 23 and the lead terminal 12, which are connected to the first heat exchanger plate 20a and the second heat exchanger plate 20b, respectively, are mounted on the die 28. At this time, a gap 28a is generated between the heat exchanger plate 20a and the die 28 due to variations in the solder thickness, inclination of the first heat exchanger plate 20a, and the like.

[0035] Afterwards, Fig. 5(b), the resin 24 is poured into the die 28 to perform transfer molding. Due to this, the resin flows into the gap 28a on the first heat exchanger plate 20a, which is Fig. 5(a), and the semiconductor module 1 in which the overmolded part 24b is formed is obtained. Then, in Fig. 5(c), only the resin 24, which is a part of the molding resin 24 on a surface of the semiconductor module 1 and overmolded 24b on top of the heat exchanger plate 20a, is removed, for example, by a laser decapper 27. By performing this process, it is possible to provide the semiconductor module 1 in a state where the stepped portion 24a provided to surround the heat exchanger plate 20a is formed and an electrode surface of the heat exchanger plate 20a is exposed.

[0036] The thermally conductive materials 21a and 21b having semi-rigid molds arranged in contact with the exposed surface of the heat exchanger plate 20a of the semiconductor module 1 and covering the molding resin 24 on one surface, and cooling water channels 26a and 26b, which are heat dissipation elements that dissipate heat to the semiconductor module 1 via the thermally conductive materials 21a and 21b, are mounted on the semiconductor module 1 manufactured as described above. Thus, the power conversion device 100 of the present invention can be provided. (FIG. 6)

[0037] In the resin 24 of the semiconductor module 1, the following relationship is established between the stepped portion 24a and the first heat-conducting material 21a. The widths of the stepped portion 24a in the direction with the lead terminal 12 are widths a1 and a2 from the left in Fig. 6, and the widths of the stepped portion 24a in the direction without the lead terminal 12 are widths b1 and b2 from above in Fig. 6. At this time, a1 > b1 or a1 > b2. Further, a2 > b1 or a2 > b2. Due to this, conventionally, the second thermally conductive material 21b has a problem that part of the pumped-out thermally conductive material 21 falls between the lead terminals 12, thereby causing a decrease in insulation quality. However, according to the present invention, the thermally conductive material 21 is less likely to pump out, and the resistance of the cooling water channel 26 increases. Even if the thermally conductive material 21b is pumped out and falls, it preferentially falls in the direction excluding the lead terminal 12, and therefore the insulation quality does not deteriorate. (FIG. 7)

[0038] Regarding the second thermally conductive material 21b in contact with the upper surface of the semiconductor module 1, the following relationship is established for the length of the second thermally conductive material 21b protruding from the stepped portion 24a of the semiconductor module 1. The distances by which the second thermally conductive material 21b protrudes from the stepped portion 24a in the direction with the lead terminal 12 are c1 and c2 from the left in Fig. 7, and the distances by which the second heat-conductive material 21b protrudes from the stepped portion 24a in the direction without the lead terminal 12 are shown as d1 and d2 from above in Fig.7. At this time, 0 < c1 < d1 or 0 < c1 < d2. Furthermore, 0 < c2 < d1 or 0 < c2 < d2. Due to this, even if the second thermally conductive material 21b is pumped out and falls, it preferentially falls in the direction excluding the lead terminal 12, and therefore the insulation quality of the lead terminal 12 does not deteriorate.

[0039] According to an embodiment of the present invention described above, the following operational effects are achieved.

[0040] (1) The semiconductor element 23; the heat exchanger plates 20a and 20b connected to the semiconductor element 23; the semiconductor module 1 formed by molding the semiconductor element 23 and the heat exchanger plates 20a and 20b with the resin 24; the thermally conductive materials 21a and 21b each having a semi-solid form disposed in contact with the heat exchanger plates 20a and 20b and covering a surface of the semiconductor module 1; and the heat dissipation member 26 that dissipates heat from the semiconductor module via the thermally conductive materials 21a and 21b are included. This can provide the power conversion device 100 that achieves cost reduction, productivity improvement, and reliability improvement.

[0041] (2) The semiconductor module 1 has the stepped portion 24a formed to surround the periphery of a part (first thermally conductive material 21a) of the thermally conductive materials 21a and 21b on a surface in contact with the thermally conductive materials 21a and 21b having the semi-solid shapes. This can suppress pumping out and provide the semiconductor module 1 in a state where an electrode surface of the heat exchanger plate 20a is exposed.

[0042] (3) The thermally conductive material 21 includes the first thermally conductive material 24a arranged such that the periphery of the first thermally conductive material 21a is surrounded by the stepped portion 24a, and the second thermally conductive material 21b in contact with the first thermally conductive material 21a and having an area larger than the area of ​​the first thermally conductive material 21a. Thus, both surfaces of the semiconductor module 1 are covered with the thermally conductive material 21, and heat generated from the semiconductor module 1 and the circuit board 6 is dissipated through the cooling water channels 26a and 26b formed by sandwiching the semiconductor module 1 from both surfaces.

[0043] (4) The first thermally conductive material 21a and the second thermally conductive material 21b are integrally arranged on a surface of the semiconductor module 1. This improves the connectivity between the first thermally conductive material 21a and the second thermally conductive material 21b and contributes to the heat dissipation of the semiconductor module 1.

[0044] (5) One surface of the semiconductor module 1 has one surface of the thermally conductive material 21a exposed, and the other surface of the semiconductor module 1 is in contact with the third thermally conductive material 21c different from the thermally conductive material 21a, and the third thermally conductive material 21c is in contact with the second heat dissipation member 26b different from the heat dissipation member 26a on the surface opposite to the surface in contact with the semiconductor module 1. This can provide the power conversion device 100 in which both surfaces of the semiconductor module 1 are cooled.

[0045] (6) The manufacturing method for the power conversion device 100 of the present invention includes: forming the semiconductor module 1 by molding, with the resin 24, the semiconductor element 23, and the heat exchanger plates 20a and 20b bonded to the semiconductor element 23; forming the stepped portion formed to expose the surface of the heat exchanger plate 20a and surround the surface of the heat exchanger plate by removing a part of the molding resin 24 from one surface of the formed semiconductor module 1; and mounting, on the semiconductor module 1, the heat-conductive material 21a having the semi-rigid shape arranged in contact with the exposed surface of the heat exchanger plate 20a and covering the molding resin 24 on one surface, and the heat dissipation member 26 that dissipates heat from the semiconductor module 1 via the heat-conductive material 21a.This can manufacture the power conversion device 100 that achieves cost reduction, improvement in productivity, and improvement in reliability.

[0046] Note that the present invention is not limited to the above embodiment, and various modifications and other configurations can be combined without departing from the gist of the present invention. The present invention is not limited to one that includes all the configurations described in the above embodiment, and includes one in which part of the configuration is deleted. List of reference symbols 1 circuit body (semiconductor module) 2 capacitors 3 positive electrode wire 4 negative electrode wire 5 Via 6 circuit board 6a Center line 7 Output wire 8 Signal connection 9 Signal wire 10 Capacitor positive electrode connection 11 Capacitor negative electrode connection 12 Supply connection 13 Wire bonding 20 Heat exchanger plate (supply frame) 20a first heat exchanger plate 20b second heat exchanger plate 21 thermally conductive material (TIM) 21a first thermally conductive material 21b second thermally conductive material 21c third thermally conductive material 22 Insulation foil 23 Semiconductor element (chip) 24 Molding resin (molding resin) 24a stepped section (projection section) 24b Overmolding 25 heat dissipation foil 26 Cooling water channel (heat dissipation element) 26a first cooling water channel 26b second cooling water channel 27 laser decappers 28 die 28a Gap between die and lead frame 100 power conversion device a1 Width of the upper surface of the stepped section in the direction with supply connection b1 Width of the upper surface of the stepped section in the direction without supply line connection in c1 Distance at which the second heat dissipation element protrudes in the direction of the supply connection d1 Distance at which the second heat dissipation element protrudes in the direction without supply connection QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 5740995

[0004]

Claims

[1] Power conversion device comprising: a semiconductor element; a heat exchanger plate connected to the semiconductor element; a semiconductor module formed by molding the semiconductor element and the heat exchanger plate with resin; a thermally conductive material having a semi-solid form arranged in contact with the heat exchanger plate and covering a surface of the semiconductor module; and a heat dissipation element that dissipates heat from the semiconductor module through the heat-conducting material. [2] The power conversion device according to claim 1, wherein the semiconductor module has a stepped portion formed to surround a periphery of a part of the thermally conductive material on the one surface in contact with the thermally conductive material having the semi-solid shape. [3] The power conversion device according to claim 2, wherein the thermally conductive material comprises a first thermally conductive material arranged such that a periphery of the first thermally conductive material is surrounded by the stepped portion, and a second thermally conductive material in contact with the first thermally conductive material and having an area larger than an area of ​​the first thermally conductive material. [4] The power conversion device according to claim 3, wherein the first thermally conductive material and the second thermally conductive material are integrally disposed on the one surface of the semiconductor module. [5] Power conversion device according to claim 1, wherein one surface of the semiconductor module has a surface of the thermally conductive material that is exposed, and another surface of the semiconductor module is in contact with a third thermally conductive material that is different from the thermally conductive material, and the third thermally conductive material is in contact with a second heat dissipation element different from the heat dissipation element on a surface opposite a surface in contact with the semiconductor module. [6] A manufacturing method for a power conversion device, comprising: Forming a semiconductor module by molding, including a resin, a semiconductor element, and a heat exchanger plate bonded to the semiconductor element; Forming a stepped portion formed to expose a surface of the heat exchanger plate and surround the surface of the heat exchanger plate by removing a part of a molding resin from a surface of the semiconductor module that has been formed; and Mounting, on the semiconductor module, a thermally conductive material having a semi-solid shape arranged in contact with an exposed surface of the heat exchanger plate and covering the molding resin on one surface, and a heat dissipation member that dissipates heat from the semiconductor module via the thermally conductive material.

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