Semiconductor module and method of manufacturing semiconductor module

Abstract

To improve the reliability of a semiconductor module.SOLUTION: A semiconductor module comprises an insulation substrate which has an insulation plate and a metal plate joined to one surface of the insulation plate, a cylindrical sleeve which has a first end face joined to the metal plate by resistance welding and a second end face on the opposite side from the first end face, and a pin which is inserted into the sleeve, wherein a welding mark of the resistance welding has smaller area than the first end face.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a semiconductor module and a method for manufacturing the semiconductor module. [Background technology]

[0002] Semiconductor modules, such as power semiconductor modules, generally include external terminals for electrically connecting semiconductor chips to external devices. For example, Patent Document 1 describes press-fitting a pin into a sleeve that is joined to a substrate by soldering, welding, or adhesive. Patent Document 2 describes joining a contact pin to an upper metallization by resistance welding. Patent Document 3 describes press-fitting an external connection terminal into a hollow hole of a contact component that is solder-joined to a conductive pattern on a substrate. Patent Document 4 describes inserting an external output terminal into a hole of a contact component that is solder-joined to an insulating substrate. Patent Document 5 describes press-fitting an implant pin into a cylindrical terminal that is solder-joined to a metal layer of an insulating wiring substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-153782 [Patent Document 2] U.S. Patent No. 8,563,364 [Patent Document 3] Japanese Patent Application Publication No. 2018-160554 [Patent Document 4] International Publication No. 2014 / 148319 [Patent Document 5] International Publication No. 2013 / 89211 Summary of the Invention [Problem to be solved by the invention]

[0004] When the substrate and sleeve are joined by solder as in Patent Documents 3-5, there is a problem that the sleeve is likely to tilt or shift position relative to the substrate between when the solder melts and when it solidifies. Also, when the load on the pin is concentrated at the joint between the substrate and sleeve, the solder joint is susceptible to deterioration due to temperature cycles.

[0005] On the other hand, Patent Documents 1 and 2 do not specifically describe welding of the sleeve and the substrate.

[0006] In consideration of the above circumstances, one aspect of the present disclosure aims to improve the reliability of a semiconductor module. [Means for solving the problem]

[0007] In order to solve the above problems, a semiconductor module according to one embodiment of the present disclosure comprises an insulating substrate having an insulating plate and a metal plate joined to one side of the insulating plate, a cylindrical sleeve having a first end face joined to the metal plate and a second end face opposite the first end face, and a pin inserted into the sleeve, wherein weld marks formed by resistance welding are formed on the first end face and on the surface of the metal plate facing the first end face, and the area of ​​the weld marks formed by resistance welding is smaller than the area of ​​the first end face.

[0008] A method for manufacturing a semiconductor module according to one embodiment of the present disclosure includes a preparation process for preparing an insulating substrate having an insulating plate and a metal plate joined to one side of the insulating plate, and a cylindrical sleeve having a first end face, a second end face opposite the first end face, and an opening provided in the second end face; a joining process for joining the first end face to the metal plate by resistance welding; and an insertion process for inserting a pin into the sleeve, wherein in the joining process, a cross-sectional area of ​​a current path formed by the resistance welding between the metal plate and the first end face is smaller than an area of ​​the first end face. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view of a semiconductor module according to a first embodiment. [Figure 2] FIG. 2 is an explanatory diagram of a sleeve in the first embodiment. [Figure 3] 5 is an explanatory view of a weld mark between a sleeve and a metal plate in the first embodiment. FIG. [Figure 4] 4 is a flowchart showing a method for manufacturing the semiconductor module according to the first embodiment. [Figure 5] FIG. 4 is an explanatory diagram of a preparation step in the first embodiment. [Figure 6] 10A and 10B are diagrams illustrating examples of arrangement of a plurality of protrusions. [Figure 7] FIG. 3 is an explanatory diagram of a joining step in the first embodiment. [Figure 8] FIG. 4 is an explanatory diagram of an insertion step in the first embodiment. [Figure 9] FIG. 10 is an explanatory view of a sleeve in the second embodiment. [Figure 10] 10 is an explanatory view of a welding mark between a sleeve and a metal plate in the second embodiment. FIG. [Figure 11] FIG. 10 is an explanatory diagram of a preparation step in the second embodiment. [Figure 12] FIG. 10 is an explanatory diagram of a joining step in the second embodiment. [Figure 13] FIG. 10 is an explanatory diagram of a joining step in the third embodiment. [Figure 14] FIG. 10 is an explanatory diagram of a second electrode in the third embodiment. [Figure 15] 10 is an explanatory view of a welding mark between a sleeve and a metal plate in the fourth embodiment. FIG. [Figure 16] FIG. 10 is an explanatory diagram of a joining step in the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] The embodiments for carrying out the present disclosure will be described with reference to the drawings. Note that the dimensions and scale of each element in each drawing may differ from those of the actual product. Furthermore, the embodiment described below is an exemplary embodiment that may be envisioned when carrying out the present disclosure. Therefore, the scope of the present disclosure is not limited to the embodiment exemplified below.

[0011] 1. First embodiment 1-1.Semiconductor module Fig. 1 is a cross-sectional view of a semiconductor module 100 according to a first embodiment. The semiconductor module 100 is a power semiconductor module, and is used, for example, in a power conversion device such as an inverter circuit. Note that for ease of explanation, Fig. 1 shows the semiconductor module 100 schematically, and the shape and number of each part of the semiconductor module 100 may differ appropriately from the actual state.

[0012] As shown in FIG. 1, the semiconductor module 100 includes an insulating substrate 30, a semiconductor chip 40, a plurality of wires 50, a plurality of external terminals 60, a case 70, and a potting material PA.

[0013] Below, each part of the semiconductor module 100 will be described in order based on FIG. 1. For ease of explanation, the term "Z axis" will be used as appropriate below. The Z axis is an axis parallel to the thickness direction or height direction of the semiconductor module 100. Hereinafter, one direction along the Z axis will be referred to as the "Z1 direction," and the direction opposite to the Z1 direction will be referred to as the "Z2 direction." The relationship between these directions and the vertical direction is not particularly limited and is arbitrary. Hereinafter, viewing in the direction along the Z axis may be referred to as a "planar view."

[0014] The insulating substrate 30 is a wiring substrate on which the semiconductor chip 40 is mounted. As the insulating substrate 30, for example, a DCB (Direct Copper Bonding) substrate, an AMB (Active Metal Brazing) substrate, an IMS (Insulated Metal Substrate) substrate, or the like is used.

[0015] The insulating substrate 30 has an insulating plate 31, a heat sink 32, and multiple metal plates 33. These are stacked in the Z1 direction in the order of metal plate 33, insulating plate 31, and heat sink 32. Here, the multiple metal plates 33 are bonded to one of the two surfaces of the insulating plate 31, and the heat sink 32 is bonded to the other surface.

[0016] The insulating plate 31 is a plate-shaped insulating member and is made of, for example, a ceramic material such as aluminum oxide, aluminum nitride, or silicon nitride, or a resin material such as epoxy resin.

[0017] The heat sink 32 is a thin, highly thermally conductive material bonded to the surface of the insulating plate 31 facing the Z1 direction. The heat sink 32 is made of a metal material such as copper or aluminum. A heat dissipation structure 400 is bonded to the heat sink 32, and heat generated in the semiconductor chip 40 is transferred to the heat dissipation structure 400 via the heat sink 32. The heat dissipation structure 400 is, for example, a structure such as a heat dissipation fin, and is made of a metal material such as aluminum or copper.

[0018] Each of the plurality of metal plates 33 is a thin conductive plate joined to the surface facing the Z2 direction of the insulating plate 31. Each of the metal plates 33 is made of a low-resistance conductive material such as copper or a copper alloy.

[0019] The semiconductor chip 40 is a power semiconductor element mounted on the insulating substrate 30, and is used as a switching element that switches between conducting and blocking current. The semiconductor chip 40 is, for example, an RC-IGBT (Reverse Conducting IGBT) that includes an IGBT (Insulated Gate Bipolar Transistor) and an FWD (Free Wheeling Diode). The semiconductor chip 40 is bonded to the metal plate 33 by a bonding material 34. The bonding material 34 is, for example, a conductive bonding material such as solder.

[0020] The semiconductor chip 40 has a first electrode 41, a second electrode 42, and a control electrode (not shown). One of the first electrode 41 and the second electrode 42 is an electrode to which a current to be controlled is input, and the other is an electrode from which that current is output. The first electrode 41 is a collector electrode that forms the surface of the semiconductor chip 40 facing the Z1 direction and also functions as a cathode electrode of the FWD. The first electrode 41 is bonded to the metal plate 33 by a bonding material 34. The second electrode 42 is an emitter electrode that forms the surface of the semiconductor chip 40 facing the Z2 direction and also functions as an anode electrode of the FWD. The control electrode is a gate electrode to which a control voltage is applied to control the on / off of the semiconductor chip 40, and together with the second electrode 42, forms the surface of the semiconductor chip 40 facing the Z2 direction.

[0021] Each of the plurality of wires 50 is a linear conductor that appropriately electrically connects each part of the insulating substrate 30 and the semiconductor chip 40. The plurality of wires 50 includes wires 50 that connect the metal plates 33 to each other and wires 50 that connect the metal plates 33 to the semiconductor chip 40.

[0022] Each of the multiple external terminals 60 is a terminal for electrically connecting the semiconductor chip 40 to an external device. Each external terminal 60 has a sleeve 61 and a pin 62. The sleeve 61 is a cylindrical conductor and is joined to the metal plate 33 by resistance welding. The pin 62 is a rod-shaped conductor and is inserted into the sleeve 61. The sleeve 61 and the pin 62 are each made of a low-resistance metal such as copper or a copper alloy. The surfaces of the sleeve 61 and the pin 62 may be plated with, for example, tin or nickel. The sleeve 61 will be described later with reference to FIGS. 2 and 3.

[0023] The case 70 is a structure that houses the semiconductor chip 40, the plurality of wires 50, and the sleeves 61 of the external terminals 60. The case 70 has a frame body 71 and a lid body 72.

[0024] The frame 71 is a frame-shaped structure that surrounds an assembly of the semiconductor chip 40, the plurality of wires 50, and the sleeves 61 of each external terminal 60. The insulating substrate 30 is fixed to the frame 71, for example, with an adhesive. The frame 71 is made of a resin composition containing various insulating resins, such as PPS (polyphenylene sulfide) resin, PBT (polybutylene terephthalate) resin, PBS (polybutylene succinate) resin, PA (polyamide) resin, or ABS (acrylonitrile-butadiene-styrene) resin.

[0025] The lid 72 is a flat plate-shaped member that closes the opening of the frame 71. Like the frame 71, the lid 72 is made of a resin composition containing various insulating resins, such as PPS (polyphenylene sulfide) resin, PBT (polybutylene terephthalate) resin, PBS (polybutylene succinate) resin, PA (polyamide) resin, or ABS (acrylonitrile-butadiene-styrene) resin. The lid 72 is provided with a plurality of through holes 72a, and the pins 62 are inserted into each of the through holes 72a. As a result, a portion of each pin 62 protrudes outside the case 70. The lid 72 may be formed integrally with the frame 71.

[0026] The potting material PA is an insulating material that fills the internal space surrounded by the insulating substrate 30 and the case 70. The potting material PA is made of, for example, a silicone resin such as silicone gel or an epoxy resin. Note that the constituent materials of the potting material PA may contain various fillers such as silicon oxide or aluminum oxide.

[0027] 1-2.External terminal sleeve 2 is an explanatory diagram of the sleeve 61 in the first embodiment. As shown in FIG. 2, the sleeve 61 has a cylindrical portion 610, a first flange 611, and a second flange 612.

[0028] The tubular portion 610 is a part of the sleeve 61 and is a cylindrical portion having an inner circumferential surface 613 with a central axis along the Z axis. In the example shown in FIG. 2, the inner diameter and the outer diameter of the tubular portion 610 are constant throughout the entire length. However, the inner diameter and the outer diameter of the tubular portion 610 do not have to be constant. Furthermore, the cross-sectional shape of the tubular portion 610 is not limited to the example shown in FIG. 2 and is arbitrary.

[0029] The first flange 611 is a part of the sleeve 61 and is an annular portion that protrudes radially outward from the end of the tubular portion 610 in the Z1 direction. The second flange 612 is a part of the sleeve 61 and is an annular portion that protrudes radially outward from the end of the tubular portion 610 in the Z2 direction. One or both of the first flange 611 and the second flange 612 may be omitted.

[0030] The sleeve 61 has a first end face F1 and a second end face F2. The first end face F1 is the end face of the sleeve 61 in the Z1 direction. The second end face F2 is the end face of the sleeve 61 opposite the first end face F1 and is the end face of the sleeve 61 in the Z2 direction.

[0031] 2, the first end face F1 is made up of the end face of the tubular portion 610 in the Z1 direction and the face of the first flange 611 facing the Z1 direction, and is a plane perpendicular to the Z axis. The second end face F2 is made up of the end face of the tubular portion 610 in the Z2 direction and the face of the second flange 612 facing the Z2 direction, and is a plane perpendicular to the Z axis.

[0032] In this embodiment, each of the first end face F1 and the second end face F2 has an opening that communicates with the internal space of the tubular portion 610. A portion of the pin 62 is inserted into the sleeve 61 through the opening provided in the second end face F2. The pin 62 is fixed to the sleeve 61, for example, by being press-fitted into the sleeve 61. Note that the method of fixing the pin 62 to the sleeve 61 is not limited to press-fitting, and may be, for example, fixing by soldering or the like. Furthermore, the cross-sectional shape of the pin 62 is not limited to the example shown in FIG. 2 and is arbitrary. Furthermore, the first end face F1 does not have to have an opening that communicates with the internal space of the tubular portion 610.

[0033] The first end face F1 is joined to the metal plate 33 via a plurality of weld marks B formed by resistance welding. Each weld mark B is formed by joining a protrusion 614 provided on the first end face F1 to the metal plate 33 by resistance welding in a manufacturing method described below. The weld marks B are integral with both the sleeve 61 and the metal plate 33. The protrusions 614 will be described later with reference to FIG. 5. Note that for convenience of description, FIG. 2 clearly shows the boundary between the weld marks B and the metal plate 33, but in reality, the boundary may not be clear due to a gradient metal composition, etc. In this embodiment, a plurality of protrusions 614 are also provided on the second end face F2, which will also be described later with reference to FIG. 5.

[0034] 2, the first end face F1 is disposed with a gap between it and the metal plate 33 in an area other than the weld mark B. Note that the first end face F1 may have a portion in contact with the metal plate 33 in an area other than the weld mark B.

[0035] In this way, the sleeve 61 is joined to the metal plate 33 by resistance welding, which provides a first advantage that the sleeve 61 is less likely to tilt or become misaligned with respect to the substrate when the metal plate 33 and the sleeve 61 are joined. Furthermore, the joining strength between the metal plate 33 and the sleeve 61 can be increased compared to an embodiment in which the sleeve 61 is joined to the metal plate 33 by soldering. Therefore, a second advantage is provided in that even if the load applied to the pin 62 is concentrated on the joint between the metal plate 33 and the sleeve 61, the joint between the metal plate 33 and the sleeve 61 is less susceptible to deterioration due to temperature cycles.

[0036] FIG. 3 is an explanatory diagram of the weld marks B between the sleeve 61 and the metal plate 33 in the first embodiment. In FIG. 3, a cross section of the weld marks B cut along the plate surface of the metal plate 33 is shown together with a plan view of the first end face F1. As shown in FIG. 3, multiple weld marks B are scattered across the first end face F1. Therefore, the area of ​​the weld marks B is smaller than the area of ​​the first end face F1. This shortens the time required to join the metal plate 33 and the sleeve 61. This allows the first advantage described above to be preferably achieved, and also prevents the heat generated during joining of the metal plate 33 and the sleeve 61 from adversely affecting other parts. The area of ​​the weld marks B is the sum of the areas of the multiple weld marks B.

[0037] In this embodiment, the metal plate 33 and the sleeve 61 are joined via a plurality of weld marks B. Here, the weld marks B in this embodiment are scattered along the circumferential direction of the outer or inner circumference of the first end face F1. This makes it possible to stabilize the position of the sleeve 61 during resistance welding without providing a recess in the metal plate 33 for inserting the first end face F1. Another advantage is that, after resistance welding, the joining strength between the metal plate 33 and the sleeve 61 can be easily increased compared to an embodiment in which the weld marks B are unevenly arranged on one side of the first end face F1.

[0038] In the example shown in Fig. 3, the weld marks B are made up of four weld marks B. The four weld marks B are arranged at equal intervals in the circumferential direction along the inner circumference of the first end face F1. The number and arrangement of the weld marks B are determined according to the number and arrangement of protrusions 614 provided on the first end face F1 in the manufacturing method described below, and are not limited to the example shown in Fig. 3 and can be any number.

[0039] The size of each weld mark B is determined to some extent depending on the size of the protrusion 614 provided on the first end face F1 in the manufacturing method described below. The width Wa of each weld mark B needs only to be smaller than the width W0 of the first end face F1, but in this embodiment, it is smaller than the distance W1 between the inner and outer peripheries of the first end face F1.

[0040] 3, each weld mark B overlaps with the cylindrical portion 610 when viewed along the Z axis. This allows current to flow efficiently through the protrusions 614, which will be described later, during resistance welding. Note that at least one of the multiple weld marks B may overlap with the first flange 611 without overlapping with the cylindrical portion 610 when viewed along the Z axis. When multiple weld marks B overlap with the first flange 611 when viewed along the Z axis, this has the advantage of making it easier to improve the stability of the posture of the sleeve 61 relative to the metal plate 33 in the joining step S20 of the manufacturing method, which will be described later.

[0041] The width Wa of each weld mark B is preferably 0.5 to 1.5 times the thickness T of the cylindrical portion 610. This effectively prevents the heat generated when joining the metal plate 33 and the sleeve 61 together from adversely affecting other portions.

[0042] As described above, by providing protrusions 614 and performing current welding, scattering is suppressed, unlike welding marks using other methods, so the width Wa of the welding mark B is 0.5 to 1.5 times the thickness T of the opposing part, and the area of ​​the welding mark B is about 1 / 3 to 1 time the area of ​​the opposing part. Furthermore, when multiple protrusions 614 are used, similar welding marks B are obtained for the multiple protrusions 614.

[0043] 1-3. Manufacturing method of semiconductor module 4 is a flowchart showing a method for manufacturing the semiconductor module 100 according to the first embodiment. The method for manufacturing the semiconductor module 100 includes, in this order, a preparation step S10, a bonding step S20, and an insertion step S30, as shown in FIG. Each step will be described below in order.

[0044] 5 is an explanatory diagram of the preparation step S10 in the first embodiment. In the preparation step S10, as shown in FIG.

[0045] In a preparation step S10 prior to the joining step S20, a plurality of protrusions 614 are provided on the first end face F1. Each of the protrusions 614 provided on the first end face F1 is an example of a "first protrusion." Each of the protrusions 614 provided on the first end face F1 is a protrusion for achieving projection welding, and becomes the aforementioned weld marks B by resistance welding in the joining step S20.

[0046] In this embodiment, a plurality of protrusions 614 are also provided on the second end surface F2. Each of the protrusions 614 provided on the second end surface F2 is an example of a "second protrusion." In the preparation step S10, the sleeve 61 has a shape that is symmetrical in the length direction. This eliminates the distinction between the top and bottom of the sleeve 61. This improves the efficiency of the resistance welding process. The sleeve 61 may also have a shape that is asymmetrical in the length direction. Furthermore, each of the protrusions 614 may be omitted from the second end surface F2.

[0047] Each protrusion 614 has a tapered shape. That is, the width of each protrusion 614 decreases toward the tip. This allows current to be effectively concentrated between the metal plate 33 and the sleeve 61 during resistance welding in the joining step S20. In the example shown in FIG. 5, each protrusion 614 has a conical shape. Note that the shape of each protrusion 614 is not limited to the example shown in FIG. 5, and may be, for example, a pyramidal shape, a truncated conical shape, or a truncated pyramidal shape, or may have a constant width.

[0048] The height H of each protrusion 614 is preferably 0.5 to 2 times the thickness T of the tubular portion 610. This makes it possible to effectively concentrate the current between the metal plate 33 and the sleeve 61 during resistance welding in the joining step S20, while preventing heat from adversely affecting other parts.

[0049] Fig. 6 is a diagram showing an example of the arrangement of multiple protrusions 614. In the example shown in Fig. 6, the number of protrusions 614 provided on the first end face F1 is four. The four protrusions 614 are arranged at equal intervals in the circumferential direction along the outer periphery of the first end face F1.

[0050] In this way, by providing a plurality of protrusions 614 on the first end face F1, the posture of the sleeve 61 can be stabilized during resistance welding in the joining step S20, even if a recess into which the first end face F1 is inserted is not provided in the metal plate 33. The number of protrusions 614 is not limited to the example shown in FIG. 6 and may be three or less or five or more. However, from the viewpoint of achieving both stability in the posture of the sleeve 61 during resistance welding and efficiency in resistance welding, the number of protrusions 614 provided on the first end face F1 must be three or more, and preferably three to seven.

[0051] The width Wb of each protrusion 614 may be smaller than the width W0 of the first end face F1, but is preferably 0.5 to 1.5 times the thickness T of the tubular portion 610. This effectively prevents the heat generated when joining the metal plate 33 and the sleeve 61 in the joining step S20 from adversely affecting other parts.

[0052] 6, each of the protrusions 614 overlaps the cylindrical portion 610 when viewed along the Z axis. This allows current to flow efficiently through the protrusions 614 during resistance welding in the joining step S20. Note that at least one of the multiple protrusions 614 may overlap the first flange 611 without overlapping the cylindrical portion 610 when viewed along the Z axis. When the multiple protrusions 614 overlap the first flange 611 when viewed along the Z axis, this has the advantage of making it easier to improve the stability of the posture of the sleeve 61 relative to the metal plate 33 in the joining step S20.

[0053] 7 is an explanatory diagram of the joining step S20 in the first embodiment. In the joining step S20, the first end surface F1 is joined to the metal plate 33 by resistance welding.

[0054] Specifically, first, the first electrode 210 is connected to the sleeve 61 to be welded, and the second electrode 220 is connected to the metal plate 33 to be welded. Then, the power supply 200 of the resistance welding machine passes a current between the first electrode 210 and the second electrode 220, thereby generating Joule heat at the contact point between the protrusion 614 and the metal plate 33. As a result, in the joining step S20, the metal plate 33 and the multiple protrusions 614 are joined by resistance welding. At this time, each protrusion 614 melts into the metal plate 33, forming a weld mark B.

[0055] The power source 200 is not particularly limited, and may be, for example, a power source for a known resistance welding machine. The first electrode 210 and the second electrode 220 are each made of a material that does not easily form an alloy with the sleeve 61, such as tungsten or molybdenum. Furthermore, in order to minimize the electrical resistance between the first electrode 210 and the sleeve 61, it is preferable that the first electrode 210 contacts the entire second end face F2. That is, it is preferable that the contact area between the first electrode 210 and the sleeve 61 is equal to or greater than the contact area between each protrusion 614 and the metal plate 33. For example, in this embodiment, since multiple protrusions 614 are provided on the second end face F2, the first electrode 210 has recesses shaped to avoid each protrusion 614, thereby making the contact area between the first electrode 210 and the sleeve 61 approximately the same as the area of ​​the second end face F2. In this case, since it is difficult to align the sleeve 61 with the first electrode 210 if the cross-sectional shape of the sleeve 61 is circular, it is preferable to make the cross-sectional shapes of the sleeve 61 and the first electrode 210 polygonal such as hexagonal or octagonal and to match the number and positions of the protrusions 614 to the cross-sectional shape of the sleeve 61, or to provide marks such as notches or cutouts on the sleeve 61 and the first electrode 210 to make alignment easier. Also, the shape of the first electrode 210 may be concave so as to press the outside of the protrusions 614 on the second end face. From the viewpoint of minimizing the electrical resistance between the second electrode 220 and the metal plate 33, the contact area between the second electrode 220 and the metal plate 33 is preferably equal to or larger than the contact area between each protrusion 614 and the metal plate 33.

[0056] In this embodiment, as described above, the second end surface F2 uses the surface of the second flange 612. In this manner, the sleeve 61 has the second flange 612 as a flange including the second end surface F2. This increases the contact area between the first electrode 210, which is an electrode for resistance welding, and the second end surface F2.

[0057] In this way, in the joining step S20, resistance welding is performed by passing a current between the first electrode 210 in contact with the sleeve 61 and the second electrode 220 in contact with the metal plate 33. This allows a current for resistance welding to flow between the metal plate 33 and the first end surface F1 of the sleeve 61 even if the insulating plate 31 is provided on the other surface of the metal plate 33.

[0058] Joining the first end face F1 to the metal plate 33 by resistance welding provides a first advantage that the sleeve 61 is less likely to tilt or shift position relative to the substrate when the metal plate 33 and the sleeve 61 are joined. Also, the joining strength between the metal plate 33 and the sleeve 61 can be increased compared to an embodiment in which the sleeve 61 is joined to the metal plate 33 by soldering. Therefore, a second advantage is provided in that the joining portion between the metal plate 33 and the sleeve 61 is less susceptible to deterioration due to temperature cycles even if the load applied to the pin 62 is concentrated on the joining portion between the metal plate and the sleeve 61.

[0059] The current flowing between the first electrode 210 and the second electrode 220 flows between the metal plate 33 and the sleeve 61 through each of the protrusions 614. This allows the metal plate 33 and the first end face F1 to be joined by projection welding. Here, in the joining step S20, the cross-sectional area of ​​the current path formed by resistance welding between the metal plate 33 and the first end face F1 is smaller than the area of ​​the first end face F1. This shortens the time required to join the metal plate 33 and the sleeve 61. This allows the aforementioned first advantage to be preferably achieved, and also prevents the heat generated during joining of the metal plate 33 and the sleeve 61 from adversely affecting other parts.

[0060] Here, as mentioned above, since the width Wb of each protrusion 614 is smaller than the width W0 of the sleeve 61, the cross-sectional area of ​​the current path due to resistance welding between the metal plate 33 and the first end face F1 can be made smaller than the area of ​​the first end face F1.

[0061] 8 is an explanatory diagram of the insertion step S30 in the first embodiment. In the insertion step S30, as shown in FIG. 8, the pin 62 is inserted into the sleeve 61. The pin 62 is fixed to the sleeve 61, for example, by being press-fitted into the sleeve 61. Note that the method of fixing the pin 62 to the sleeve 61 is not limited to press-fitting, and it may also be fixed by, for example, soldering or the like.

[0062] Although not shown, between the bonding step S20 and the insertion step S30, for example, by known techniques, the semiconductor chip 40 is mounted on the insulating substrate 30 and a plurality of wires 50 are formed in this order. After the insertion step S30, for example, the case 70 is attached and the potting material PA is formed in this order. In this way, the semiconductor module 100 is obtained.

[0063] As described above, the method for manufacturing the semiconductor module 100 of this embodiment can improve the reliability of the semiconductor module 100.

[0064] 2. Second embodiment A second embodiment of the present disclosure will be described below. In the following exemplary embodiment, for elements whose actions and functions are similar to those of the above embodiment, the reference numerals used in the description of the above embodiment will be used, and detailed descriptions of each element will be omitted as appropriate.

[0065] 9 is an explanatory diagram of a sleeve 61A in the second embodiment. This embodiment is similar to the first embodiment except that an insulating substrate 30A and a sleeve 61A are used instead of the insulating substrate 30 and the sleeve 61 of the first embodiment.

[0066] The insulating substrate 30A is configured similarly to the insulating substrate 30 of the first embodiment, except that it includes a metal plate 33A instead of the metal plate 33 of the first embodiment. The metal plate 33A is configured similarly to the metal plate 33 of the first embodiment, except that it has a recess 331.

[0067] The recess 331 is a depression into which the first end face F1 is inserted, and has a shape corresponding to the first end face F1. In the example shown in Fig. 9, the recess 331 has a concave curved shape. Note that the shape of the recess 331 is determined according to the shape of the first end face F1, and is not limited to the example shown in Fig. 9.

[0068] The sleeve 61A has the same configuration as the sleeve 61 of the first embodiment, except that the first flange 611 and the second flange 612 of the first embodiment are omitted and a bottom portion 615 is added. Note that the sleeve 61A also omits the protrusion 614 on the second end face F2.

[0069] The bottom portion 615 is a part of the sleeve 61B, and is a portion that closes the opening in the Z1 direction of the tubular portion 610. By having such a bottom portion 615, the sleeve 61A has a bottomed tubular shape with the first end face F1 as the bottom surface.

[0070] 9, the first end face F1 is made up of the end face of the tubular portion 610 in the Z1 direction and the surface of the bottom portion 615 facing the Z1 direction, and has a curved shape that is convex toward the insulating plate 31. The second end face F2 is made up of the end face of the tubular portion 610 in the Z2 direction, and is a plane that is perpendicular to the Z axis.

[0071] In this embodiment, the first end face F1 is joined to the metal plate 33A via one weld mark B. Here, the first end face F1 is inserted into the recess 331. This stabilizes the position and posture of the sleeve 61B during resistance welding. In the example shown in FIG. 9, the first end face F1 is disposed with a gap between it and the wall surface of the recess 331 in an area other than the weld mark B. Note that the first end face F1 may have a portion that contacts the wall surface of the recess 331 in an area other than the weld mark B.

[0072] In this embodiment, the weld mark B is located at the center of the first end face F1. Therefore, the weld mark B encompasses the center of the first end face F1. This makes it easier to concentrate current at the center of the first end face F1 during resistance welding, significantly shortening the time required to join the metal plate 33A and the sleeve 61. Note that in this embodiment, there may be a plurality of weld marks B, i.e., a plurality of protrusions 614. For example, instead of or in addition to the weld marks B or protrusions 614 encompassing the center of the first end face F1, the weld marks B or protrusions 614 may be provided scattered circumferentially along the inner or outer circumference of the first end face F1.

[0073] FIG. 10 is an explanatory diagram of a weld mark B between the sleeve 61A and the metal plate 33A in the second embodiment. In FIG. 10, a cross section of the weld mark B cut along the plate surface of the metal plate 33A is shown together with a plan view of the first end face F1. As shown in FIG. 10, one weld mark B is provided on the first end face F1, and the area of ​​the weld mark B is smaller than the area of ​​the first end face F1. This shortens the time required to join the metal plate 33A and the sleeve 61A.

[0074] 11 is an explanatory diagram of the preparation step S10 in the second embodiment. In the preparation step S10 in this embodiment, as shown in FIG.

[0075] In the preparation step S10 prior to the joining step S20, one protrusion 614 is provided on the first end face F1 of this embodiment. The one protrusion 614 is located at the center of the first end face F1. Therefore, the one protrusion 614 includes a protrusion that encompasses the center of the first end face F1. This makes it easier to concentrate current at the center of the first end face F1 during resistance welding, and therefore the time required to join the metal plate 33A and the sleeve 61 can be extremely short.

[0076] 12 is an explanatory view of the joining step S20 in the second embodiment. In the joining step S20 in this embodiment, the first end surface F1 of the sleeve 61A is joined to the metal plate 33A by resistance welding. At this time, one protrusion 614 provided on the first end surface F1 melts into the metal plate 33A to form a weld mark B.

[0077] In the joining step S20 of this embodiment, the first end surface F1 is inserted into the recess 331. This makes it possible to stabilize the position and posture of the sleeve 61 during resistance welding.

[0078] In this embodiment, as described above, the first end face F1 has a curved shape that convexly extends toward the insulating plate 31, which makes it difficult for portions of the first end face F1 other than the center thereof to come into contact with the metal plate 33A during resistance welding. This makes it easy to concentrate current at the center of the first end face F1 during resistance welding. Furthermore, in this embodiment, the second end face F2 does not have multiple protrusions 614, which makes it easy to increase the contact area between the first electrode 210 and the sleeve 61A without having to modify the shape of the first electrode 210.

[0079] After the above-described joining step S20, the insertion step S30 and the like are performed in the same manner as in the first embodiment. According to the above-described second embodiment, the reliability of the semiconductor module can also be improved.

[0080] 3. Third embodiment A third embodiment of the present disclosure will be described below. In the following exemplary embodiment, for elements whose actions and functions are similar to those of the above-described embodiment, the reference numerals used in the description of the above-described embodiment will be used, and detailed descriptions of each element will be omitted as appropriate.

[0081] Fig. 13 is an explanatory diagram of the joining step S20 in the third embodiment. The joining step S20 in this embodiment is similar to the joining step S20 in the first embodiment, except that the configuration of the second electrode 220 is different and jigs 310 and 320 are used. However, Fig. 13 illustrates an example in which a sleeve 61B is used instead of the sleeve 61 in the first embodiment.

[0082] The sleeve 61B is configured similarly to the sleeve 61 of the first embodiment, except that the first flange 611, the second flange 612, and the multiple protrusions 614 on the second end face F2 of the first embodiment are omitted. Omitting the first flange 611 and the second flange 612 in this way has the advantage of making it easier to reduce the distance between the first electrode 210 and the second electrode 220. Note that, even in this embodiment, one or both of the first flange 611 and the second flange 612 do not necessarily have to be omitted.

[0083] In the joining step S20 of this embodiment, a plurality of second electrodes 220 are used to surround the periphery of the sleeve 61. This shortens the current path between the first electrode 210 and each second electrode 220, and makes it possible to uniform the current between the metal plate 33 and the first end face F1.

[0084] Fig. 14 is an explanatory diagram of second electrodes 220-1 to 220-4 in the third embodiment. Fig. 14 shows a cross section of second electrodes 220-1 to 220-4 and sleeve 61B cut along a plane perpendicular to the Z axis. Each of second electrodes 220-1 to 220-4 is second electrode 220. Note that hereinafter, second electrodes 220-1 to 220-4 may be referred to as second electrode 220 without being distinguished from one another.

[0085] The second electrodes 220-1, 220-2, 220-3, and 220-4 are arranged in this order at intervals in the circumferential direction around the sleeve 61B. The interval between the second electrodes 220-3 and 220-4 is greater than the width of the sleeve 61B. This allows the sleeve 61B to be introduced into the region surrounded by the second electrodes 220-1 to 220-4 through the interval between the second electrodes 220-3 and 220-4.

[0086] 14, the distance between second electrode 220-1 and second electrode 220-4, the distance between second electrode 220-1 and second electrode 220-2, and the distance between second electrode 220-2 and second electrode 220-3 are each smaller than the distance between second electrode 220-3 and second electrode 220-4. This increases the contact area between second electrode 220 and metal plate 33. Note that these distances are not limited to the example shown in FIG. 14 and may be, for example, equal to or different from each other.

[0087] By using such a plurality of second electrodes 220-1 to 220-4, the second electrodes 220 can be easily arranged to surround the periphery of the sleeve 61.

[0088] A jig 310 is inserted between second electrodes 220-1 and 220-4, between second electrodes 220-1 and 220-2, and between second electrodes 220-2 and 220-3. A jig 320 is inserted between second electrodes 220-1 and 220-4.

[0089] During resistance welding, the three jigs 310 and 320 are arranged to surround the periphery of the sleeve 61B and are in contact with the outer periphery of the sleeve 61B. The relative positions of the three jigs 310 are fixed by members (not shown). Meanwhile, the jig 320 is movable in a direction away from the three jigs 310 to a position where the sleeve 61B can pass between the second electrodes 220-3 and 220-4.

[0090] The jigs 310, 320 are not in contact with the second electrode 220 and are electrically insulated from the second electrode 220. The jigs 310, 320 are made of an insulating material such as ceramics or a resin composition. The jigs 310, 320 may be made of a conductive material such as a metal material as long as they are electrically insulated from the second electrode 220. In this case, the jigs 310, 320 may also serve as the first electrode 210.

[0091] As described above, in the joining step S20, the sleeve 61B is held by the jigs 310, 320 between the plurality of second electrodes 220. This makes it possible to stabilize the position and posture of the sleeve 61B during resistance welding, even if the second electrodes 220 are arranged so as to surround the periphery of the sleeve 61B.

[0092] The reliability of the semiconductor module can also be improved by the third embodiment described above. Note that the number and shapes of the second electrodes 220 and the jigs 310, 320 are not limited to the example shown in Fig. 14. For example, the number of second electrodes 220 may be two or three, or may be five or more.

[0093] 4. Fourth embodiment A fourth embodiment of the present disclosure will be described below. In the following exemplary embodiment, for elements whose actions and functions are similar to those of the above-described embodiment, the reference numerals used in the description of the above-described embodiment will be used, and detailed descriptions of each element will be omitted as appropriate.

[0094] 15 is an explanatory diagram of a sleeve 61C in the fourth embodiment. This embodiment is similar to the first embodiment except that a sleeve 61C is used instead of the sleeve 61 of the first embodiment.

[0095] The sleeve 61C is configured similarly to the sleeve 61 of the first embodiment, except that the first flange 611 and the plurality of protrusions 614 on the second end face F2 of the first embodiment are omitted.

[0096] 15, the first end face F1 is formed by the end face of the tubular portion 610 in the Z1 direction and is along a plane perpendicular to the Z axis. The second end face F2 is formed by the end face of the tubular portion 610 in the Z2 direction and a surface of the second flange 612 facing the Z2 direction, and is a plane perpendicular to the Z axis.

[0097] 16 is an explanatory view of the joining step S20 in the fourth embodiment. In the joining step S20 in this embodiment, the first end surface F1 of the sleeve 61C is joined to the metal plate 33 by resistance welding. At this time, a plurality of protrusions 614 provided on the first end surface F1 melt into the metal plate 33, thereby forming a plurality of weld marks B.

[0098] In this embodiment, since the second end face F2 does not have multiple protrusions 614, it is easy to increase the contact area between the first electrode 210 and the sleeve 61C without having to devise a new shape for the first electrode 210. Moreover, since the sleeve 61C has the second flange 612, coupled with the fact that the second end face F2 does not have multiple protrusions 614, it is easy to increase the contact area between the first electrode 210 and the second end face F2.

[0099] According to the fourth embodiment described above, the reliability of the semiconductor module can also be improved.

[0100] 5. Variations Specific modified embodiments that can be added to the above-described embodiments are exemplified below. Two or more embodiments arbitrarily selected from the following examples may be combined as appropriate within a range that does not contradict each other.

[0101] 5-1. Variation 1 In the above-described embodiment, an example is given in which at least one protrusion 614 is provided on the first end face F1, but this is not limited to this embodiment, and it is sufficient that the cross-sectional area of ​​the current path due to resistance welding between the metal plate 33 or metal plate 33A and the first end face F1 be smaller than the area of ​​the first end face F1.

[0102] For example, the protrusion 614 may be omitted from the sleeve 61A of the second embodiment. In this case, the curvature of the concavely curved recess 331 of the second embodiment may be made smaller than the curvature of the convexly curved first end face F1, or a metal plate 33 without the recess 331 may be used, thereby making the cross-sectional area of ​​the current path smaller than the area of ​​the first end face F1.

[0103] Furthermore, even if the protrusion 614 is not provided on the first end face F1, the cross-sectional area of ​​the current path can be made smaller than the area of ​​the first end face F1 by providing a protrusion on the metal plate 33 or the metal plate 33A that contacts the first end face F1.

[0104] Furthermore, even without providing a protrusion 614 on the first end face F1, the cross-sectional area of ​​the current path can be made smaller than the area of ​​the first end face F1 by placing a welding member such as a metal piece having a smaller cross-sectional area than the first end face F1 between the first end face F1 and the metal plate 33 or the metal plate 33A.

[0105] 5-2. Variation 2 In the above-described embodiment, an example is given of a configuration in which a semiconductor chip 40 or the like is sealed using a frame body 71, a potting material PA, and a lid body 72, but this is not limited to this configuration, and the present disclosure can also be applied to a full mold configuration in which a semiconductor chip 40 or the like is sealed using a single resin composition.

[0106] 5-3. Variation 3 In the above embodiment, the semiconductor chip 40 is an RC-IGBT, but the embodiment of the semiconductor chip 40 is not limited to the above embodiment. For example, various electronic elements such as an IGBT (Insulated Gate Bipolar Transistor) or an SBD (Schottky Barrier Diode) may be used as the semiconductor chip 40. Also, a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) whose semiconductor layer is formed of silicon (Si) or silicon carbide (SiC) may be used as the semiconductor chip 40. In an embodiment in which the semiconductor chip 40 is configured as a MOSFET, the first electrode 41 is a drain electrode and the second electrode 42 is a source electrode.

[0107] 6. Notes From the above-described exemplary embodiments, the following configurations can be understood, for example.

[0108] (Appendix 1) A first aspect, which is a preferred example of a semiconductor module of the present disclosure, comprises an insulating substrate having an insulating plate and a metal plate joined to one side of the insulating plate, a tubular sleeve having a first end face joined to the metal plate and a second end face opposite the first end face, and a pin inserted into the sleeve, wherein weld marks formed by resistance welding are formed on the first end face and on the surface of the metal plate facing the first end face, and the area of ​​the weld marks formed by resistance welding is smaller than the area of ​​the first end face.

[0109] In the above-described embodiment, the sleeve is joined to the metal plate by resistance welding, which provides a first advantage that the sleeve is less likely to tilt or shift relative to the substrate when the metal plate and sleeve are joined. Furthermore, the strength of the joint between the metal plate and the sleeve can be increased compared to an embodiment in which the sleeve is joined to the metal plate by soldering. Therefore, a second advantage is also provided in that the joint between the metal plate and the sleeve is less susceptible to deterioration due to temperature cycles, even if the load applied to the pin is concentrated at the joint between the metal plate and the sleeve. Furthermore, because the area of ​​the weld marks created by resistance welding is smaller than the area of ​​the first end face, the time required to join the metal plate and the sleeve is reduced. Therefore, the first advantage is preferably achieved, and the heat generated when the metal plate and the sleeve are joined is prevented from adversely affecting other parts.

[0110] (Supplementary Note 2) In a second aspect which is a preferred example of the first aspect, the sleeve has a flange including the second end surface. In the above aspect, the contact area between the electrode for resistance welding and the second end surface can be increased.

[0111] (Note 3) In a third aspect, which is a preferred example of the first or second aspect, the sleeve has a bottomed cylindrical shape with the first end face as its bottom, and the weld mark encompasses the center of the first end face. In this aspect, current can be easily concentrated at the center of the first end face during resistance welding, so the time required to join the metal plate and the sleeve is extremely short.

[0112] (Note 4) In a fourth aspect, which is a preferred example of the third aspect, the first end surface has a curved shape that is convex toward the insulating plate. This aspect makes it difficult for parts other than the center of the first end surface to come into contact with the metal plate during resistance welding. This makes it easy to concentrate current at the center of the first end surface during resistance welding.

[0113] (Supplementary Note 5) In a fifth aspect which is a preferred example of the fourth aspect, the metal plate has a recess having a shape corresponding to the first end face, and the first end face is inserted into the recess. In this aspect, the position and posture of the sleeve can be stabilized during resistance welding.

[0114] (Note 6) In a sixth aspect, which is a preferred example of the first aspect, the weld marks are scattered along the circumferential direction of the outer or inner circumference of the first end face. In this aspect, the position of the sleeve can be stabilized during resistance welding without providing a recess in the metal plate into which the first end face is inserted.

[0115] (Appendix 7) A seventh aspect, which is a preferred example of the method for manufacturing a semiconductor module of the present disclosure, includes a preparation step of preparing an insulating substrate having an insulating plate and a metal plate joined to one side of the insulating plate, and a cylindrical sleeve having a first end face, a second end face opposite the first end face, and an opening provided in the second end face, a joining step of joining the first end face to the metal plate by resistance welding, and an insertion step of inserting a pin into the sleeve, wherein in the joining step, a cross-sectional area of ​​a current path formed by the resistance welding between the metal plate and the first end face is smaller than an area of ​​the first end face.

[0116] In the above-described embodiment, the sleeve is joined to the metal plate by resistance welding, which provides a first advantage that the sleeve is less likely to tilt or shift relative to the substrate when the metal plate and sleeve are joined. Furthermore, the strength of the joint between the metal plate and the sleeve can be increased compared to an embodiment in which the sleeve is joined to the metal plate by soldering. Therefore, a second advantage is also provided in that the joint between the metal plate and the sleeve is less susceptible to deterioration due to temperature cycles, even if the load applied to the pin is concentrated at the joint between the metal plate and the sleeve. Furthermore, in the joining process, the cross-sectional area of ​​the current path formed by resistance welding between the metal plate and the first end face is smaller than the area of ​​the first end face, which shortens the time required to join the metal plate and the sleeve. Therefore, the first advantage is preferably achieved, and the heat generated when joining the metal plate and the sleeve is prevented from adversely affecting other parts.

[0117] (Supplementary Note 8) In an eighth aspect which is a preferred example of the seventh aspect, the sleeve has a flange including the second end surface. In the above aspect, it is possible to increase the contact area between an electrode for resistance welding and the second end surface.

[0118] (Supplementary Note 9) In a ninth aspect which is a preferred example of the seventh or eighth aspect, in the preparing step, the first end surface is provided with at least one first projection having a width smaller than the width of the sleeve, and in the joining step, the metal plate and the at least one first projection are joined by resistance welding. In the above aspect, the cross-sectional area of ​​the current path formed by resistance welding between the metal plate and the first end surface can be made smaller than the area of ​​the first end surface.

[0119] (Supplementary Note 10) In a tenth aspect which is a preferred example of the ninth aspect, the sleeve has a bottomed tubular shape with the first end face as a bottom face, and the at least one first projection includes a projection that encompasses the center of the first end face. In this aspect, current can be easily concentrated at the center of the first end face during resistance welding, so the time required to join the metal plate and the sleeve can be extremely short.

[0120] (Supplementary Note 11) In the eleventh aspect, which is a preferred example of the tenth aspect, the first end surface has a curved shape that is convex toward the insulating plate. In this aspect, it is possible to make it difficult for parts other than the center of the first end surface to come into contact with the metal plate during resistance welding. Therefore, it is easy to concentrate current at the center of the first end surface during resistance welding.

[0121] (Supplementary Note 12) In a twelfth aspect which is a preferred example of the eleventh aspect, the metal plate has a recess having a shape corresponding to the first end surface, and in the joining step, the first end surface is inserted into the recess. In this aspect, the position and posture of the sleeve can be stabilized during resistance welding.

[0122] (Supplementary Note 13) In a thirteenth aspect which is a preferred example of the ninth aspect, the at least one first projection is a plurality of projections. In this aspect, the position of the sleeve during resistance welding can be stabilized without providing a recess in the metal plate into which the first end face is inserted.

[0123] (Appendix 14) In a fourteenth aspect, which is a preferred example of the thirteenth aspect, the second end surface is provided with at least one second protrusion, and in the preparation step, the sleeve has a shape that is symmetrical in the longitudinal direction. In this aspect, the distinction between the top and bottom of the sleeve can be eliminated. This can improve the efficiency of resistance welding.

[0124] (Supplementary Note 15) In a fifteenth aspect which is a preferred example of any of the seventh to fourteenth aspects, the joining step performs the resistance welding by passing a current between a first electrode in contact with the sleeve and at least one second electrode in contact with the metal plate. In the above aspect, even if an insulating plate is provided on the other surface of the metal plate, a current for resistance welding can be passed between the metal plate and the first end surface of the sleeve.

[0125] (Supplementary Note 16) In a sixteenth aspect which is a preferred example of the fifteenth aspect, in the joining step, the at least one second electrode surrounds the periphery of the sleeve. In this aspect, it is possible to shorten the current path between the first electrode and the second electrode and to make the current uniform between the metal plate and the first end surface.

[0126] (Supplementary Note 17) In a seventeenth aspect which is a preferred example of the sixteenth aspect, the at least one second electrode is a plurality of second electrodes. In this aspect, the second electrodes can be easily arranged so as to surround the periphery of the sleeve.

[0127] (Appendix 18) In an 18th aspect which is a preferred example of either the 16th or 17th aspect, in the joining step, the sleeve is held by a jig through the gap between the plurality of second electrodes. In this aspect, even if the second electrodes are arranged so as to surround the periphery of the sleeve, the position and posture of the sleeve can be stabilized during resistance welding. [Explanation of symbols]

[0128] 30...insulating substrate, 30A...insulating substrate, 31...insulating plate, 32...heat sink, 33...metal plate, 33A...metal plate, 34...bonding material, 40...semiconductor chip, 41...first electrode, 42...second electrode, 50...wire, 60...external terminal, 61...sleeve, 61A...sleeve, 61B...sleeve, 62...pin, 70...case, 71...frame, 72...lid, 72a...through hole, 100...semiconductor module, 200...power supply, 210...first electrode, 220...second electrode, 220-1...second electrode, 2 20-2...second electrode, 220-3...second electrode, 220-4...second electrode, 310...jig, 320...jig, 331...recess, 400...heat dissipation structure, 610...tubular portion, 611...first flange, 612...second flange, 613...inner surface, 614...protrusion, 615...bottom, B...welding mark, F1...first end face, F2...second end face, H...height, PA...potting material, S10...preparation process, S20...bonding process, S30...insertion process, T...thickness, W0...width, W1...distance, Wa...width, Wb...width.

Claims

1. an insulating substrate having an insulating plate and a metal plate bonded to one surface of the insulating plate; a cylindrical sleeve having a first end surface joined to the metal plate and a second end surface opposite to the first end surface; a pin inserted into the sleeve; a weld mark formed by resistance welding on the first end surface and on a surface of the metal plate facing the first end surface; an area of ​​the weld mark formed by resistance welding is smaller than an area of ​​the first end surface; Semiconductor module.

2. the sleeve has a flange including the second end surface; The semiconductor module according to claim 1 .

3. the sleeve has a cylindrical shape with a bottom, the first end surface being a bottom surface, The welding mark includes a center of the first end surface. The semiconductor module according to claim 1 .

4. the first end surface has a curved shape that is convex toward the insulating plate; The semiconductor module according to claim 3 .

5. the metal plate has a recess having a shape corresponding to the first end surface, The first end surface is inserted into the recess. The semiconductor module according to claim 4 .

6. The welding marks are scattered along the circumferential direction of the outer periphery or the inner periphery of the first end surface. The semiconductor module according to claim 1 .

7. an insulating substrate having an insulating plate and a metal plate bonded to one surface of the insulating plate; a preparing step of preparing a cylindrical sleeve having a first end surface, a second end surface opposite to the first end surface, and an opening provided in the second end surface; a joining step of joining the first end surface to the metal plate by resistance welding; an inserting step of inserting a pin into the sleeve, In the joining step, a cross-sectional area of ​​a current path formed by resistance welding between the metal plate and the first end surface is smaller than an area of ​​the first end surface. A method for manufacturing a semiconductor module.

8. the sleeve has a flange including the second end surface; The method for manufacturing a semiconductor module according to claim 7 .

9. In the preparing step, at least one first protrusion having a width smaller than a width of the sleeve is provided on the first end surface, the joining step joins the metal plate and the at least one first projection by resistance welding; The method for manufacturing a semiconductor module according to claim 7 .

10. the sleeve has a cylindrical shape with a bottom, the first end surface being a bottom surface, the at least one first protrusion includes a protrusion encompassing the center of the first end surface; The method for manufacturing a semiconductor module according to claim 7 .

11. the first end surface has a curved shape that is convex toward the insulating plate; The method for manufacturing a semiconductor module according to claim 10 .

12. the metal plate has a recess having a shape corresponding to the first end surface, In the joining step, the first end surface is inserted into the recess. The method for manufacturing a semiconductor module according to claim 11 .

13. the at least one first protrusion is a plurality of protrusions; The method for manufacturing a semiconductor module according to claim 7 .

14. At least one second protrusion is provided on the second end surface, In the preparation step, the sleeve has a shape that is symmetrical in the length direction. The method for manufacturing a semiconductor module according to claim 13 .

15. the joining step performs the resistance welding by passing a current between a first electrode in contact with the sleeve and at least one second electrode in contact with the metal plate; The method for manufacturing a semiconductor module according to claim 7 .

16. the at least one second electrode is a plurality of second electrodes; The method for manufacturing a semiconductor module according to claim 15.

17. In the bonding step, the at least one second electrode surrounds the sleeve. The method for manufacturing a semiconductor module according to claim 16 .

18. In the joining step, the sleeve is held by a jig through the plurality of second electrodes. The method for manufacturing a semiconductor module according to claim 16 or 17.

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