Semiconductor device, power conversion device, and semiconductor device manufacturing method

Abstract

To improve liquid tightness at a boundary between a substrate installation part at which a substrate is installed and a body part to which the substrate installation part is attached.SOLUTION: A heat sink 30 comprises: a body part 31 having a penetration opening 31a penetrated and formed so as to be connected to a flow channel Y; and a substrate installation part 32 which is pressed and inserted in the penetration opening 31a and at which a power device 20 is installed. The body part 31 includes an embedded and filled part 31g that is plastic-deformed and filled between the substrate installation part 32 and an embedded surface 31e which is part of an internal surface 31d of the penetration opening 31a; and a taper reception surface 31f which is part of the internal surface 31d of the penetration opening 31a differing from the embedded surface 31e and is formed in a taper shape. The substrate installation part 32 includes: a pressed and inserted part 32a having the embedded and filled part 31g filled between the pressed and inserted part and the embedded surface 31e; and a taper shape part 32b that is formed in a taper shape and is pressed and connected to the taper reception surface 31f.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a semiconductor device, a power conversion device, and a method for manufacturing a semiconductor device. [Background technology]

[0002] For example, Patent Document 1 discloses a semiconductor device including a ceramic insulating substrate on which a semiconductor element is mounted. The semiconductor device disclosed in Patent Document 1 includes a base plate on which the ceramic insulating substrate is mounted and an Fe frame having an opening. The Fe frame completely surrounds the periphery of the base plate and is bonded to the base plate via an adhesive. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-230367 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, semiconductor devices may have a flow path through which a coolant flows to cool a substrate on which a semiconductor element is mounted, etc. Such a flow path is provided in a member on which the above-mentioned substrate is mounted. However, as in Patent Document 1, when a substrate mounting portion such as a base plate and a main body portion such as an Fe frame are bonded only with an adhesive, it is not possible to ensure liquid-tightness between the substrate mounting portion and the main body portion, and the coolant may leak from the flow path.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to improve the liquid-tightness at the boundary between the substrate mounting section on which the substrate is mounted and the main body section to which the substrate mounting section is attached. [Means for solving the problem]

[0006] The present invention employs the following configuration as a means for solving the above problems.

[0007] A first aspect of the present invention is a semiconductor device comprising: a substrate on which a semiconductor element is mounted; and a support plate portion that supports the substrate and forms at least a part of a flow path through which a coolant flows to cool the substrate; the support plate portion comprises a main body portion having a through opening formed therethrough to connect to the flow path; and a substrate installation portion that is pressed into the through opening and on which the substrate is provided; the main body portion has an embedded filling portion that is plastically deformed and filled between an embedded surface that is part of the inner wall surface of the through opening and the substrate installation portion; and a tapered receiving surface that is part of the inner wall surface of the through opening different from the embedded surface and is formed into a tapered shape; and the substrate installation portion has a press-fit insertion portion that is filled with the embedded filling portion between the embedded surface and the pressed-in insertion portion, and a tapered portion that is formed into a tapered shape and is pressed against the tapered receiving surface.

[0008] A second aspect of the present invention is a method for manufacturing a semiconductor device comprising a support plate portion that forms at least a part of a flow path through which a coolant flows to cool a substrate, the support plate portion comprising a main body portion having a through opening formed therethrough to connect to the flow path, and a substrate installation portion that is press-fitted into the through opening, the method comprising a substrate installation process in which the substrate, on which a semiconductor element is mounted, is installed on the substrate installation portion before it is pressed into the through opening, and a press-fitting process in which the substrate installation portion with the substrate installed is press-fitted into the through opening, the press-fitting process plastically deforming a part of the main body portion to form an embedded filling portion between the embedded surface that is part of the inner wall surface of the through opening and the substrate installation portion, and the press-fitting process presses the tapered portion of the substrate installation portion against a tapered receiving surface that is part of the inner wall surface of the through opening, different from the embedded surface, and that is formed in a tapered shape. [Effects of the Invention]

[0009] According to the present invention, the substrate mounting portion is press-fit into the through opening of the main body portion. Also, according to the present invention, an embedded filling portion is provided between the substrate mounting portion and the inner wall surface of the main body portion. Furthermore, according to the present invention, the tapered portion of the substrate mounting portion is pressed against the tapered receiving surface of the main body portion. Therefore, the present invention can improve the liquid-tightness at the boundary between the substrate mounting portion on which the substrate is mounted and the main body portion to which the substrate mounting portion is attached. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a circuit diagram showing a schematic electrical configuration of a power conversion device according to an embodiment of the present invention. [Figure 2] 1 is an exploded perspective view showing a schematic structural outline of a power conversion device according to an embodiment of the present invention; [Figure 3] FIG. 1 is a schematic exploded perspective view of a power module included in an intelligent power module according to an embodiment of the present invention. [Figure 4] 4 is a cross-sectional view taken along the line AA in FIG. 3. [Figure 5] FIG. 2 is a schematic exploded cross-sectional view of a heat sink provided in the power module according to the embodiment of the present invention. [Figure 6] 5A to 5C are explanatory diagrams for explaining a method for manufacturing a power module according to an embodiment of the present invention. [Figure 7] 5A to 5C are explanatory diagrams for explaining a method for manufacturing a power module according to an embodiment of the present invention. [Figure 8] 1A is a schematic enlarged view including a through opening of a main body portion of a heat sink provided in a power module according to one embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along the line BB of FIG. 1A. [Figure 9] 5A to 5C are explanatory diagrams for explaining a method for manufacturing a power module according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a semiconductor device, a power conversion device, and a method for manufacturing a semiconductor device according to the present invention will be described below with reference to the drawings.

[0012] FIG. 1 is a circuit diagram showing a schematic electrical configuration of a power conversion device 1 of this embodiment. The power conversion device 1 of this embodiment is mounted on a vehicle such as an electric automobile, and is provided between a motor M and a battery B. The power conversion device 1 of this embodiment performs power conversion between the motor M and the battery B. For example, the power conversion device 1 of this embodiment converts DC power supplied from the battery B into three-phase AC power and supplies it to the motor M. The power conversion device 1 also converts regenerative power (AC power) from the motor M into DC power and supplies it to the battery B.

[0013] As shown in Fig. 1, the power conversion device 1 of this embodiment has a power conversion circuit H. As described above, the power conversion circuit H converts DC power into AC power. Furthermore, the power conversion circuit H converts AC power into DC power. Such a power conversion circuit H includes a capacitor C and an inverter circuit E. Note that the power conversion device 1 may also include, for example, a step-up / step-down converter or a DC / DC converter (not shown). Furthermore, if the vehicle has multiple motors M, the power conversion device 1 may also include multiple inverter circuits E.

[0014] The power conversion device 1 of this embodiment also includes conductive lines BU through which power is conducted. For example, the power conversion device 1 of this embodiment includes a conductive line BU that connects the inverter circuit E and the battery B, and a conductive line BU that connects the inverter circuit E and the motor M.

[0015] As shown in FIG. 1, the inverter circuit E has three legs R corresponding to the respective phases of the motor M. Each leg R has an upper arm HA and a lower arm LA. The upper arm HA is connected to the positive side of a battery B via a conductive line BU. The lower arm LA is connected to the negative side of the battery B via a conductive line BU. The upper arm HA and the lower arm LA are connected in series. An output terminal that connects the legs R and the motor M is connected between the upper arm HA and the lower arm LA.

[0016] As shown in FIG. 1, the power conversion device 1 of this embodiment includes power devices 20 (substrates on which semiconductor elements are mounted) corresponding to each leg R. That is, in this embodiment, the power conversion device 1 includes three power devices 20. Each power device 20 includes a power transistor corresponding to the upper arm HA and a power transistor corresponding to the lower arm. That is, in this embodiment, each power device 20 includes two power transistors. Each of these power transistors is formed using, for example, a plurality of semiconductor elements.

[0017] 1, one end of the capacitor C is connected to a conductive line BU connected to the positive electrode of the battery B. The other end of the capacitor C is connected to a conductive line BU connected to the negative electrode of the battery B. The capacitor C smoothes the DC power between the battery B and the inverter circuit E.

[0018] FIG. 2 is an exploded perspective view showing a schematic structural configuration of the power conversion device 1 of this embodiment. As shown in FIG. 2, the power conversion device 1 of this embodiment includes an inverter case 2, an intelligent power module 3, and a capacitor unit 4. The power conversion device 1 may also include other components, such as a reactor unit forming a step-up / step-down circuit and a DC-DC converter unit forming a DC-DC converter. When a plurality of inverter circuits E are included, the power conversion device 1 may also include a plurality of intelligent power modules 3. The power conversion device 1 may also include a step-up / step-down circuit unit separate from the intelligent power module 3.

[0019] The inverter case 2 is a case that houses the intelligent power module 3, the capacitor unit 4, etc., and includes a center plate 2a and a case cover 2b. The center plate 2a and the case cover 2b are formed as separate parts that can be detached from each other. In FIG. 2, the case cover 2b is shown separated from the center plate 2a and positioned above it. However, the installation posture of the power conversion device 1 is not particularly limited. In other words, the power conversion device 1 may be mounted on a vehicle so that the case cover 2b is positioned to the side of the center plate 2a.

[0020] The central plate 2a has a bottom wall to which the intelligent power modules 3 and the capacitor units 4 are fixed, and side walls that surround the intelligent power modules 3 and the capacitor units 4. In other words, the central plate 2a is formed in the shape of a container that is open on the case cover 2b side. Such central plate 2a is provided with water channels as necessary, and is formed to be able to guide the coolant that cools the intelligent power modules 3 and the capacitor units 4.

[0021] The case cover 2b is fixed to the center plate 2a and covers the intelligent power module 3 and the capacitor unit 4. That is, the intelligent power module 3 and the capacitor unit 4 are exposed when the case cover 2b is detached from the center plate 2a.

[0022] Such an inverter case 2 is fixed to, for example, a housing (not shown) that covers the motor M or a gear case that houses a gear that transmits power generated by the motor M to the outside. In such a case, for example, the center plate 2a is fastened to the motor housing or the gear case using a bolt (not shown) or the like. Note that if the housing that covers the motor M has a space for accommodating the power conversion device 1, the case cover 2b may be omitted.

[0023] The inverter case 2 also holds bus bars that form part or all of the conductive line BU (see Figure 1) that connects the battery B to the intelligent power module 3 and the capacitor unit 4, and the conductive line BU (see Figure 1) that connects the intelligent power module 3 to the motor M.

[0024] The intelligent power module 3 includes a power module 3a (semiconductor device) and a board unit 3b (control board). The power module 3a is a module provided with a plurality of power devices 20 (described later). In other words, the power module 3a forms an inverter circuit E with the plurality of power devices 20.

[0025] The board unit 3b is stacked on the power module 3a. This board unit 3b includes, for example, a gate driver board and an ECU (Electronic Control Unit) board. The gate driver board is a board provided with a gate driver that generates a drive signal for the inverter circuit E formed by the power module 3a. The ECU board is a board provided with an ECU that controls the gate driver board. Such a board unit 3b controls the power device 20.

[0026] The capacitor unit 4 is a unit that houses a capacitor element therein. The capacitor unit 4 is connected to the power module 3a. The capacitor unit 4 forms the capacitor C shown in FIG.

[0027] 3 is a schematic exploded perspective view of a power module 3a included in the intelligent power module 3. As shown in this figure, the power module 3a includes a module case 10, the above-mentioned power device 20 (substrate), a heat sink 30 (support plate portion), and a lead frame 40.

[0028] The module case 10 is fixed to the heat sink 30 and houses the power devices 20 and the like. The module case 10 has an opening 11 for each power device 20 to house the power device 20.

[0029] Fig. 4 is a schematic cross-sectional view of the power module 3a in which one power device 20 is enlarged, taken along the line AA in Fig. 3. As shown in Fig. 4, the module case 10 is fixed onto the heat sink 30 via an adhesive 50. Such a module case 10 is fixed to the surface 30a of the heat sink 30 so as to surround each power device 20.

[0030] The power conversion device 1 of this embodiment also includes a bus bar 60 (conductive member) that is molded into the module case 10 and thereby held in the module case 10. The bus bar 60 is connected to the power device 20 via the lead frame 40. In this embodiment, the power conversion device 1 of this embodiment includes a bus bar 60 (hereinafter referred to as bus bar 61) that conducts power between the battery B and the power device 20, and a bus bar 60 (hereinafter referred to as bus bar 62) that conducts power between the power device 20 and the motor M.

[0031] The bus bar 61 is molded into the module case 10 with a connection terminal 61a on the battery B side and a portion where the lead frame 40 is joined exposed from the module case 10. The connection terminal 61a is connected to the capacitor unit 4 and a power supply terminal (not shown), and is connected to the battery B via the power supply terminal.

[0032] The bus bar 62 is molded into the module case 10 with a connection terminal 62a on the motor M side and a portion where the lead frame 40 is joined exposed from the module case 10. The connection terminal 62a is connected to the motor M.

[0033] As shown in FIG. 3 , the power conversion device 1 of this embodiment includes a control terminal 70 molded in the module case 10. The control terminal 70 is molded in the module case 10 in an L-shaped bent state. One end of the control terminal 70 protrudes upward from the module case 10. This one end of the control terminal 70 is inserted into a through-hole provided in the board unit 3b and is electrically connected to the board unit 3b. The other end of the control terminal 70 is arranged so as to be exposed upward at the opening 11. The other end of such a control terminal 70 is connected to the power device 20 by a bonding wire (not shown). A plurality of such control terminals 70 are contained within the module case 10.

[0034] 4, each power device 20 includes a mounting substrate 21 and a semiconductor element 22. The mounting substrate 21 is a substrate on which the semiconductor element 22 is mounted. The mounting substrate 21 includes a sheet-like insulating base material 23, a front conductor layer 24 provided on the front surface (one surface) of the insulating base material 23, and a back conductor layer 25 provided on the back surface of the insulating base material 23.

[0035] The insulating substrate 23 is made of an insulating material such as ceramics and is formed in a sheet shape. A front-side conductor layer 24 is formed on the surface of the insulating substrate 23 (the surface on the semiconductor element 22 side). This front-side conductor layer 24 is a metal layer that is electrically connected to the semiconductor element 22 and forms part of a conductive circuit. In other words, the front-side conductor layer 24 is a conductor layer on which the semiconductor element 22 is mounted.

[0036] A back-side conductor layer 25 is formed on the other surface of the insulating substrate 23 (the surface opposite to the semiconductor element 22). This back-side conductor layer 25 forms part of a heat transfer path that transfers heat conducted from the semiconductor element 22, etc. to the heat sink 30. The surface of this back-side conductor layer 25 opposite to the insulating substrate 23 is the mounting surface when the power device 20 is mounted on the heat sink 30. This mounting surface is joined to the heat sink 30 via solder 100. In this embodiment, the mounting substrate 21 includes the back-side conductor layer 25. However, the mounting substrate 21 does not necessarily need to include the back-side conductor layer 25. In this case, the insulating substrate 23 is joined to the heat sink 30.

[0037] For example, the semiconductor element 22 is mounted on the front conductor layer 24. There is no limit to the number of semiconductor elements 22 mounted on the front conductor layer 24. Such semiconductor elements 22 can be formed using a silicon (Si) semiconductor. Alternatively, the semiconductor elements 22 can be formed using a wide-gap semiconductor such as a silicon carbide (SiC) semiconductor or a gallium nitride (GaN) semiconductor.

[0038] Each power device 20 is a substrate on which a semiconductor element 22 is mounted as described above. Such a power device 20 is placed on a heat sink 30 and housed in the opening 11 of the module case 10.

[0039] The heat sink 30 supports the module case 10 and the power device 20. The heat sink 30 also absorbs heat from the power device 20 to cool the power device 20. The heat sink 30 is fixed to the central plate 2a so that its underside is exposed to a flow path provided in the central plate 2a. In other words, the heat sink 30 forms at least a part of a flow path Y through which the coolant X flows between the heat sink 30 and the central plate 2a.

[0040] As shown in Fig. 4, in this embodiment, the heat sink 30 includes a main body portion 31 and a substrate mounting portion 32. Fig. 5 is a schematic exploded cross-sectional view of the heat sink 30. The main body portion 31 is the entire portion or a portion of the heat sink 30 excluding the substrate mounting portion 32. The main body portion 31 has the same number of through openings 31a as the number of substrate mounting portions 32. Each through opening 31a is formed to penetrate the main body portion 31 so as to be connected to the flow path Y.

[0041] Each through opening 31a has, in the penetration direction, a power device side portion 31b located on the power device 20 side and a flow path side portion 31c located on the flow path Y side. These power device side portion 31b and flow path side portion 31c are connected in the penetration direction to form one through opening 31a.

[0042] The power device-side portion 31b is a portion into which a press-fit insertion portion 32a (described later) of the substrate installation portion 32 is inserted. As shown in Fig. 5, the inner wall surface 31d of the through opening 31a has an embedded surface 31e located in the power device-side portion 31b and a tapered receiving surface 31f located in the flow path-side portion 31c. In other words, the embedded surface 31e and the tapered receiving surface 31f are part of the through opening 31a.

[0043] As shown in FIG. 5 and other figures, the main body 31 has an embedded filling portion 31g. The embedded filling portion 31g is a portion that is filled by plastic deformation between the embedding surface 31e and the substrate mounting portion 32. That is, in this embodiment, the embedded filling portion 31g is formed by a part of the main body 31. The embedded filling portion 31g is formed so as to surround the substrate mounting portion 32 in the circumferential direction. Such embedded filling portion 31g is formed by press-fitting the substrate mounting portion 32 into the through opening 31a, thereby plastically deforming a protrusion 31h (see FIG. 8) of the main body 31, which will be described later.

[0044] Such a main body 31 is formed of a material having lower rigidity than the substrate mounting portion 32. In addition, the main body 31 is formed of a material that is lighter than the substrate mounting portion 32. For example, the main body 31 is formed of aluminum or an aluminum alloy.

[0045] The buried surface 31e has the above-described buried filling portion 31g formed on the entire surface. That is, the protrusion 31h of the main body 31 is plastically deformed to become the buried filling portion 31g that fills the entire surface of the buried surface 31e. The buried filling portion 31g tightly adheres the boundary between the main body 31 and the substrate installation portion 32.

[0046] The tapered receiving surface 31f is a part of the inner wall surface 31d of the through opening 31a that is different from the embedded surface 31e. The tapered receiving surface 31f is formed in a tapered shape. That is, the tapered receiving surface 31f is a tapered surface. Specifically, the tapered receiving surface 31f is inclined so as to move outward from the through opening 31a as it moves from the power device 20 side toward the flow path Y side, and is a surface facing the flow path Y side. A tapered portion 32b (described later) of the substrate installation portion 32 is pressed against such a tapered receiving surface 31f.

[0047] The board mounting portion 32 is a portion where the power devices 20 are provided. The power devices 20 are joined to the board mounting portion 32 via solder 100. The board mounting portion 32 is formed in a shape that allows it to be press-fitted into the through opening 31a of the main body 31. The number of board mounting portions 32 provided is the same as the number of power devices 20.

[0048] 5, the substrate installation portion 32 has a press-fit insertion portion 32a, a tapered portion 32b, and fins 32c. The press-fit insertion portion 32a is a portion that is press-fit into the power device side portion 31b of the through opening 31a. The press-fit insertion portion 32a is formed in a shape that embeds the power device side portion 31b. The power device 20 is bonded to the surface of the press-fit insertion portion 32a opposite to the tapered portion 32b.

[0049] The tapered portion 32b is a portion located closer to the flow path Y than the press-fit insertion portion 32a, and is formed in a tapered shape. The tapered portion 32b has a pressure-contact surface 32d that bulges outward from the substrate installation portion 32 relative to the press-fit insertion portion 32a. The tapered portion 32b is formed in a shape that buries the flow path side portion 31c of the through opening 31a. The pressure-contact surface 32d is formed in a tapered shape. In other words, the pressure-contact surface 32d is a tapered surface. Specifically, the pressure-contact surface 32d is inclined so as to extend outward from the through opening 31a as it moves from the power device 20 side toward the flow path Y side, and is a surface facing the power device 20 side. The tapered receiving surface 31f of the main body portion 31 is pressed against such a pressure-contact surface 32d.

[0050] The fins 32c are portions that protrude from the tapered portion 32b toward the flow path Y. The fins 32c are portions that increase the contact area between the substrate placement portion 32 and the coolant X. A plurality of fins 32c are provided. Note that the fins may be provided on the main body portion 31.

[0051] The substrate mounting portion 32 is made of a material having a higher thermal conductivity than the main body portion 31. For example, the substrate mounting portion 32 is made of copper.

[0052] The lead frame 40 is joined to the power device 20 and the bus bar 60. The lead frame 40 is joined to the power device 20 via solder 100. The lead frame 40 is also joined to the bus bar 60 via solder 100.

[0053] Furthermore, the opening 11 of the module case 10 is filled with a sealing material 90. The power device 20 and other components are covered with the sealing material 90. This prevents the power device 20 and other components from coming into contact with air and external moisture.

[0054] Next, a method for manufacturing the power module 3a will be described with reference to Figures 6 to 9. Figures 6 to 9 are schematic diagrams showing some of the manufacturing steps for the power module 3a of this embodiment.

[0055] First, as shown in Fig. 6, the power device 20 is placed on the substrate placement portion 32. Here, the power device 20 is attached to the substrate placement portion 32 before the substrate placement portion 32 is press-fitted into the through opening 31a of the main body portion 31. The power device 20 is joined to the substrate placement portion 32 via solder 100. The process shown in Fig. 6 is a power device placement process (substrate placement process) in which the power device 20 is placed on the substrate placement portion 32 before being press-fitted into the through opening 31a.

[0056] Next, as shown in Fig. 7, the substrate mounting portion 32 on which the power device 20 is mounted is press-fitted into the through opening 31a. Fig. 8(a) is a schematic enlarged view including the through opening 31a of the main body 31 before the substrate mounting portion 32 is press-fitted. Fig. 8(b) is a BB cross-sectional view of Fig. 8(b). As shown in these figures, the main body 31 has a plurality of protrusions 31h provided on the inner wall surface 31d of the through opening 31a.

[0057] Each protrusion 31h is formed to protrude from the inner wall surface 31d toward the center of the through opening 31a. Each protrusion 31h is provided on the embedded surface 31e of the inner wall surface 31d. Each protrusion 31h is formed to extend linearly from the end of the embedded surface 31e on the tapered receiving surface 31f side to the end opposite the tapered receiving surface 31f. When the board mounting portion 32 is press-fitted into the through opening 31a, these protrusions 31h are plastically deformed to become embedded filling portions 31g that are embedded between the embedded surface 31e and the board mounting portion 32.

[0058] 7, when the substrate mounting portion 32 is press-fitted into the through opening 31a, the press-fit insertion portion 32a (see FIG. 5) of the substrate mounting portion 32 is press-fitted into the power device side portion 31b (see FIG. 5) of the through opening 31a. Then, the pressure contact surface 32d of the substrate mounting portion 32 is press-fitted against the tapered receiving surface 31f of the through opening 31a. The process shown in FIG. 7 is a press-fitting process in which the substrate mounting portion 32 on which the power device 20 is mounted is press-fitted into the through opening 31a.

[0059] 7, the module case 10 may be adhered to the main body 31 before the board installation portion 32 is press-fitted into the through opening 31a. However, the module case 10 may also be adhered to the main body 31 after the board installation portion 32 is press-fitted into the through opening 31a.

[0060] 9, the lead frame 40 is placed and bonded to the power device 20 and the bus bar 60 by reflow. Furthermore, bonding wires and a sealing material 90 (not shown) are provided to manufacture the power module 3a.

[0061] The power module 3a manufactured in this manner is connected to the capacitor unit 4 and the like, and housed in the inverter case 2. At this time, the terminals of the capacitor unit 4 and the connection terminals 61a of the bus bars 61 are fastened together with screws. Here, the screws are screwed together to fasten the terminals of the capacitor unit 4 and the connection terminals 61a, thereby fastening the terminals of the capacitor unit 4 and the connection terminals 61a together.

[0062] The power module 3a of this embodiment as described above includes a power device 20 and a heat sink 30. The power device 20 is a substrate on which a semiconductor element 22 is mounted. The heat sink 30 supports the power device 20. The heat sink 30 forms at least a part of a flow path Y through which a coolant X flows to cool the power device 20.

[0063] The heat sink 30 also includes a main body 31 and a substrate mounting portion 32. The main body 31 has a through opening 31a formed therethrough to be connected to the flow path Y. The substrate mounting portion 32 is press-fitted into the through opening 31a. The power device 20 is provided on the substrate mounting portion 32.

[0064] The main body 31 also has an embedded filling portion 31g and a tapered receiving surface 31f. The embedded filling portion 31g is plastically deformed and filled between the substrate installation portion 32 and an embedded surface 31e, which is part of the inner wall surface 31d of the through opening 31a. The tapered receiving surface 31f is part of the inner wall surface 31d of the through opening 31a that is different from the embedded surface 31e. The tapered receiving surface 31f is formed in a tapered shape.

[0065] The substrate installation portion 32 has a press-fit insertion portion 32a and a tapered portion 32b. The press-fit insertion portion 32a is filled with an embedded filling portion 31g between itself and the embedded surface 31e. The tapered portion 32b is formed in a tapered shape and is pressed against the tapered receiving surface 31f.

[0066] According to the power module 3a of this embodiment, the substrate mounting portion 32 is press-fitted into the through opening 31a of the main body 31. Furthermore, according to the power module 3a of this embodiment, an embedded filling portion 31g is provided between the inner wall surface 31d of the main body 31 and the substrate mounting portion 32. Furthermore, according to the power module 3a of this embodiment, the tapered portion 32b of the substrate mounting portion 32 is press-fitted against the tapered receiving surface 31f of the main body 31. Therefore, the power module 3a of this embodiment can improve the liquid-tightness at the boundary between the substrate mounting portion 32 on which the power device 20 is mounted and the main body 31 to which the substrate mounting portion 32 is attached.

[0067] Furthermore, in the power module 3a of this embodiment, the main body portion 31 is formed of a material having lower rigidity than the substrate mounting portion 32. According to the power module 3a of this embodiment, by press-fitting the substrate mounting portion 32 into the through opening 31a of the main body portion 31, a part of the main body portion 31 can be easily plastically deformed, and the embedded filling portion 31g can be easily formed.

[0068] Furthermore, in the power module 3a of this embodiment, the main body 31 is formed of a material that is lighter than the substrate mounting portion 32. According to the power module 3a of this embodiment, the weight of the heat sink 30 can be reduced compared to when the entire heat sink 30 is formed of the same material as the substrate mounting portion 32.

[0069] Furthermore, in the power module 3a of this embodiment, the substrate mounting portion 32 is formed of a material having a higher thermal conductivity than the main body portion 31. According to the power module 3a of this embodiment, the heat of the power devices 20 can be transferred to the coolant X more efficiently than when the entire heat sink 30 is formed of the same material as the main body portion 31, and the cooling efficiency of the power devices 20 can be improved.

[0070] Furthermore, in the power module 3a of this embodiment, the embedded surface 31e is located closer to the power device 20 than the tapered receiving surface 31f. According to the power module 3a of this embodiment, it is also possible to locate the tapered receiving surface 31f closer to the power device 20 than the embedded surface 31e. However, by positioning the embedded surface 31e closer to the power device 20 than the tapered receiving surface 31f, the tapered receiving surface 31f extends outward beyond the embedded surface 31e, and a wide contact area can be secured between the tapered receiving surface 31f and the pressure contact surface 32d of the substrate installation portion 32.

[0071] The power converter 1 of this embodiment includes the above-described power module 3a and performs power conversion using the power module 3a. Therefore, the power converter 1 of this embodiment can improve the liquid-tightness at the boundary between the board mounting portion 32 on which the power device 20 is mounted and the main body portion 31 to which the board mounting portion 32 is attached.

[0072] The method for manufacturing the power module 3a of this embodiment is a method for manufacturing the power module 3a including the heat sink 30 that forms at least a part of the flow path Y through which the coolant X flows to cool the power device 20. The method for manufacturing the power module 3a of this embodiment also includes a power device installation step and a press-fitting step.

[0073] The power device installation process is a process of installing the power device 20, on which the semiconductor element 22 is mounted, on the substrate installation portion 32 before the power device 20 is press-fitted into the through opening 31a. The press-fitting process is a process of press-fitting the substrate installation portion 32, on which the power device 20 is installed, into the through opening 31a. In the press-fitting process, a part of the main body 31 is plastically deformed to form an embedded filling portion 31g between the substrate installation portion 32 and an embedded surface 31e, which is part of the inner wall surface 31d of the through opening 31a. Furthermore, in the press-fitting process, the tapered portion 32b of the substrate installation portion 32 is pressed against a tapered receiving surface 31f, which is part of the inner wall surface 31d of the through opening 31a and different from the embedded surface 31e and is formed in a tapered shape.

[0074] According to the manufacturing method of the power module 3a of this embodiment, the substrate mounting portion 32 is press-fitted into the through opening 31a of the main body portion 31. Furthermore, an embedded filling portion 31g is provided between the inner wall surface 31d of the main body portion 31 and the substrate mounting portion 32. Furthermore, the tapered portion 32b of the substrate mounting portion 32 is pressed against the tapered receiving surface 31f of the main body portion 31. Therefore, the manufacturing method of the power module 3a of this embodiment can improve the liquid-tightness at the boundary between the substrate mounting portion 32 on which the power device 20 is mounted and the main body portion 31 to which the substrate mounting portion 32 is attached.

[0075] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to the above-described embodiments. The shapes and combinations of the components shown in the above-described embodiments are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0076] In the above embodiment, the semiconductor device of the present invention is applied to a power converter, i.e., the power converter includes the semiconductor device. However, the semiconductor device of the present invention is not limited to being used in a power converter, and can be applied to a semiconductor device in which a substrate on which a semiconductor element is mounted is provided on a support plate portion that forms a part of a flow path.

[0077] The above embodiment can also be described as follows, for example:

[0078] (Appendix 1) a substrate on which a semiconductor element is mounted; a support plate portion that supports the substrate and forms at least a part of a flow path through which a cooling liquid that cools the substrate flows; Equipped with The support plate portion is a main body portion having a through opening formed therethrough so as to be connected to the flow path; a substrate installation portion press-fitted into the through opening and on which the substrate is installed; Equipped with The main body portion is a buried filling portion that is plastically deformed and filled between the substrate placement portion and a buried surface that is a part of the inner wall surface of the through opening; a tapered receiving surface that is a part of the inner wall surface of the through opening and is different from the embedding surface and is formed in a tapered shape; and The substrate placement unit includes: a press-fit insertion portion having an embedded filling portion filled between the press-fit insertion portion and the embedded surface; a tapered portion formed in a tapered shape and pressed against the tapered receiving surface; have A semiconductor device characterized by:

[0079] (Appendix 2) 2. The semiconductor device according to claim 1, wherein the main body is formed of a material having a lower rigidity than the substrate placement portion.

[0080] (Appendix 3) 3. The semiconductor device according to claim 1, wherein the main body is made of a material that is lighter than the substrate placement portion.

[0081] (Appendix 4) 4. The semiconductor device according to any one of claims 1 to 3, wherein the substrate placement portion is made of a material having a higher thermal conductivity than the main body portion.

[0082] (Appendix 5) 5. The semiconductor device according to claim 1, wherein the embedded surface is located closer to the substrate than the tapered receiving surface.

[0083] (Appendix 6) A semiconductor device according to any one of appendices 1 to 5, Power conversion is performed using the semiconductor device A power conversion device characterized by:

[0084] (Appendix 7) A method for manufacturing a semiconductor device including a support plate portion that forms at least a part of a flow path through which a coolant for cooling a substrate flows, comprising: The support plate portion is a main body portion having a through opening formed therethrough so as to be connected to the flow path; a substrate installation portion press-fitted into the through opening; Equipped with a substrate installation step of installing the substrate, on which a semiconductor element is mounted, on the substrate installation portion before the substrate is press-fitted into the through opening; a press-fitting step of press-fitting the substrate mounting portion on which the substrate is mounted into the through-opening; and In the press-fitting step, a portion of the main body is plastically deformed to form a buried filling portion between a buried surface, which is a portion of an inner wall surface of the through opening, and the substrate installation portion; In the press-fitting step, a tapered portion of the substrate installation portion is pressed against a tapered receiving surface that is a part of an inner wall surface of the through opening portion different from the embedding surface and is formed in a tapered shape. 10. A method for manufacturing a semiconductor device comprising the steps of: [Explanation of symbols]

[0085] 1...power conversion device, 2...inverter case, 3...intelligent power module, 3a...power module, 3b...board unit, 4...capacitor unit, 10...module case, 11...opening, 20...power device (board), 21...mounting board, 22...semiconductor element, 23...insulating substrate, 24...front conductor layer, 25...rear conductor layer, 30...heat sink (support plate portion), 30a...surface, 31...main body portion, 31a...through opening, 31b...power device side portion, 31c...flow path side portion, 31d...inner wall surface, 31e...embedded surface, 31f...tapered receiving surface, 31g...embedded filling portion, 31h...protrusion, 32...board installation portion, 32a...press-fit insertion portion, 32b...tapered portion, 32c...fin, 32d...press-contact surface, X...coolant, Y...flow path

Claims

1. a substrate on which a semiconductor element is mounted; a support plate portion that supports the substrate and forms at least a part of a flow path through which a cooling liquid that cools the substrate flows; Equipped with The support plate portion is a main body portion having a through opening formed therethrough so as to be connected to the flow path; a substrate installation portion press-fitted into the through opening and on which the substrate is installed; Equipped with The main body portion is a buried filling portion that is plastically deformed and filled between the substrate placement portion and a buried surface that is a part of the inner wall surface of the through opening; a tapered receiving surface that is a part of the inner wall surface of the through opening and is different from the embedding surface and is formed in a tapered shape; and The substrate placement unit includes: a press-fit insertion portion having an embedded filling portion filled between the press-fit insertion portion and the embedded surface; a tapered portion formed in a tapered shape and pressed against the tapered receiving surface; have A semiconductor device characterized by:

2. 2. The semiconductor device according to claim 1, wherein the main body is made of a material having a lower rigidity than the substrate placement portion.

3. 3. The semiconductor device according to claim 1, wherein the main body is made of a material that is lighter than the substrate placement portion.

4. 3. The semiconductor device according to claim 1, wherein the substrate placement portion is made of a material having a higher thermal conductivity than the main body portion.

5. 3. The semiconductor device according to claim 1, wherein the embedded surface is located closer to the substrate than the tapered receiving surface.

6. A semiconductor device according to claim 1 or 2, Power conversion is performed using the semiconductor device A power conversion device characterized by:

7. A method for manufacturing a semiconductor device including a support plate portion that forms at least a part of a flow path through which a coolant for cooling a substrate flows, comprising: The support plate portion is a main body portion having a through opening formed therethrough so as to be connected to the flow path; a substrate installation portion press-fitted into the through opening; Equipped with a substrate installation step of installing the substrate, on which a semiconductor element is mounted, on the substrate installation portion before the substrate is press-fitted into the through opening; a press-fitting step of press-fitting the substrate mounting portion on which the substrate is mounted into the through-opening; and In the press-fitting step, a portion of the main body is plastically deformed to form a buried filling portion between a buried surface, which is a portion of an inner wall surface of the through opening, and the substrate installation portion; In the press-fitting step, a tapered portion of the substrate installation portion is pressed against a tapered receiving surface that is a part of an inner wall surface of the through opening portion different from the embedding surface and is formed in a tapered shape.

10. A method for manufacturing a semiconductor device comprising the steps of:

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