Semiconductor module

Abstract

To effectively prevent a semiconductor module from overheating.SOLUTION: A semiconductor module includes a metal plate, a plurality of switching elements bonded to one side of the metal plate, a temperature fuse bonded to one side of the metal plate, and external terminals bonded to the temperature fuse so as to be electrically connected to the plurality of switching elements.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a semiconductor module. [Background technology]

[0002] BACKGROUND ART Semiconductor modules, typified by power semiconductor modules, include switching elements such as IGBTs (Insulated Gate Bipolar Transistors), as disclosed in, for example, Patent Documents 1 to 6. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-99547 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-175506 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-216755 [Patent Document 4] Japanese Patent Application Publication No. 5-135850 [Patent Document 5] Japanese Patent Application Publication No. 2018-81947 [Patent Document 6] Japanese Patent Application Laid-Open No. 2005-123516 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventionally, fail-safe measures have been taken, such as stopping the operation of the module when the temperature detected by a temperature sensor built into the module exceeds a predetermined temperature, or installing a current fuse in the main current path of the module.

[0005] However, in power modules that pass large currents, it is difficult to balance performance with the use of current fuses. Therefore, there is room for improvement in terms of achieving both fail-safe measures and continuity performance in the event of a system abnormality.

[0006] In consideration of the above circumstances, one aspect of the present disclosure aims to suitably prevent an excessive temperature rise in a semiconductor module. [Means for solving the problem]

[0007] In order to solve the above problems, a semiconductor module according to a preferred embodiment of the present disclosure comprises a metal plate, a plurality of switching elements bonded to one side of the metal plate, a temperature fuse bonded to one side of the metal plate, and an external terminal bonded to the temperature fuse and thereby electrically connected to the plurality of switching elements. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view of a semiconductor module according to an embodiment. [Figure 2] 1 is a cross-sectional view of a portion of a semiconductor module according to an embodiment. [Figure 3] FIG. 2 is a plan view illustrating the arrangement of a thermal fuse. [Figure 4] 1 is a circuit diagram showing an application example of a semiconductor module according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the dimensions and scale of each part in the drawings may differ from those in reality. Furthermore, the embodiments described below are preferred specific examples of the present disclosure. Therefore, various technically preferable limitations are applied to the following embodiments. However, the scope of the present disclosure is not limited to these embodiments unless otherwise specified in the following description to the effect that the present disclosure is limited.

[0010] 1. Embodiment 1-1. Overall configuration of semiconductor module Fig. 1 is a plan view of a semiconductor module 10 according to an embodiment. The semiconductor module 10 is a power module such as an IGBT (Insulated Gate Bipolar Transistor) module. In the example shown in Fig. 1, the semiconductor module 10 is an IPM (Intelligent Power Module) incorporating an inverter bridge circuit and a control circuit, and is used for power control in devices such as inverters or rectifiers mounted in appliances such as air conditioners, railway vehicles, automobiles, and household electrical appliances.

[0011] 1, the semiconductor module 10 includes a plurality of switching elements 21, a plurality of control elements 22, a plurality of diodes 23, a lead group 30, a sealing resin 40, a wire group 50, an insulating substrate 60, and a thermal fuse 70. For ease of explanation, in FIG. 2, only the outer edge of the sealing resin 40 is simply shown by a two-dot chain line.

[0012] First, the outline of each part of the semiconductor module 10 will be sequentially described below based on FIG. 1. For convenience, the following description will be made using the mutually orthogonal X-axis, Y-axis, and Z-axis as appropriate. The Z-axis is an axis parallel to the thickness direction of the semiconductor module 10. Hereinafter, one direction along the X-axis is the X1 direction, and the direction opposite to the X1 direction is the X2 direction. One direction along the Y-axis is the Y1 direction, and the direction opposite to the Y1 direction is the Y2 direction. One direction along the Z-axis is the Z1 direction, and the direction opposite to the Z1 direction is the Z2 direction. The relationship between these directions and the vertical direction is not particularly limited and can be arbitrary.

[0013] The switching element 21 is a semiconductor switching element such as an IGBT (Insulated Gate Bipolar Transistor) or a power MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor). In the example shown in Fig. 1, the switching element 21 is a switching element such as an RC (Reverse-Conducting)-IGBT, and further includes a diode such as an FWD (Free Wheeling Diode).

[0014] A drain electrode or collector electrode, which is the input electrode of the switching element, is provided on the back surface of the switching element 21, and a cathode electrode, which is the output electrode of the diode, is provided so as to be electrically connected to the input electrode. On the other hand, a source electrode or emitter electrode, which is the output electrode of the switching element, and a gate electrode, which is the control electrode, are provided on the front surface of the switching element 21, and an anode electrode, which is the input electrode of the diode, is provided so as to be electrically connected to the output electrode.

[0015] In the example shown in Fig. 1, there are six switching elements 21. The six switching elements 21 configure three half-bridge circuits for the U phase, V phase, and W phase. Of the six switching elements 21, the three switching elements 21 on the lower side (X2 direction) in Fig. 1 are high-potential side elements, and the three switching elements 21 on the upper side (X1 direction) in Fig. 1 are low-potential side elements.

[0016] The number of switching elements 21 is not limited to the example shown in Fig. 1 and may be any number. Diodes such as FWDs (Free Wheeling Diodes) may be provided separately from the switching elements 21. In this case, for example, the output electrode of the switching element 21 is electrically connected to the input electrode of the paired diode via a bonding wire.

[0017] Each of the plurality of control elements 22 is an electronic component such as an IC (Integrated Circuit) for controlling the driving of the switching elements 21. In the example shown in Fig. 1, there are two control elements 22. Of the two control elements 22, the control element 22 on the lower side (X2 direction) in Fig. 1 corresponds to the three switching elements 21 on the high potential side, and the control element 22 on the upper side (X1 direction) in Fig. 1 corresponds to the three switching elements 21 on the low potential side. Each of the two control elements 22 is electrically connected to the control electrodes of the corresponding three switching elements 21 via bonding wires 52 of the wire group 50, and controls the driving of the corresponding three switching elements 21.

[0018] In this embodiment, which will be described in detail later based on Figure 4, of the two control elements 22, the control element 22 corresponding to the three switching elements 21 on the low potential side has a temperature sensor 22a, and when the temperature detected by the temperature sensor 22a reaches a predetermined temperature, the power supply to the three switching elements 21 on the low potential side is cut off.

[0019] Each of the plurality of diodes 23 is a diode such as a BSD (Boot Strap Diode). In the example shown in Fig. 1, there are three diodes 23, and the three diodes 23 are electrically connected to the front surface of the control element 22 on the high potential side via bonding wires 54 of the wire group 50.

[0020] The insulating substrate 60 is a substrate such as a DCB (Direct Copper Bonding) substrate or a DBA (Direct Bonded Aluminum) substrate for mounting a plurality of switching elements 21. The insulating substrate 60 has an insulating plate 61, a conductor pattern 62 bonded to the front surface of the insulating plate 61, and a conductor plate 63 bonded to the back surface of the insulating plate 61.

[0021] The insulating plate 61 is a plate-shaped member made of a resin composition. The resin composition includes, for example, a resin such as epoxy resin and an inorganic filler such as silicon dioxide (SiO2) or boron nitride (BN). The conductive pattern 62 is made of a metal such as copper or aluminum and includes multiple conductive plates that are separated from one another. In the example shown in FIG. 1, the conductive pattern 62 includes metal plates 62a, 62b, 62c, and 62d as the multiple conductive plates. The back surfaces of three high-potential side switching elements 21 are joined by soldering or the like to the surface of the metal plate 62a facing the Z1 direction. The back surface of one low-potential side switching element 21 is joined by soldering or the like to each of the metal plates 62b, 62c, and 62d. The conductive plate 63 is made of a metal such as copper or aluminum and has the function of dissipating heat from the switching elements 21.

[0022] In an embodiment using such an insulating substrate 60, the metal plates 62a, 62b, 62c, and 62d can be easily installed at desired positions during the manufacture of the semiconductor module 10. Furthermore, since the insulating plate 61 is made of a resin composition, the insulating plate 61 is more susceptible to damage due to excessive heating than in an embodiment in which the insulating plate 61 is made of ceramics. Therefore, as will be described later, the effect of preventing excessive heating of the semiconductor module 10 is significant. Note that the shape of the conductor pattern 62 shown in FIG. 1 is one example and is not limited to this. Furthermore, the insulating plate 61 is not limited to an embodiment in which it is made of a resin composition, and may be made of ceramics such as aluminum nitride, aluminum oxide, or silicon nitride.

[0023] The lead group 30 is a collection of multiple leads for electrically connecting each of the multiple switching elements 21, the multiple control elements 22, and the multiple diodes 23 to a substrate (not shown) on which the semiconductor module 10 is mounted. The lead group 30 is made of a metal such as copper, a copper alloy, aluminum, an aluminum alloy, or an iron alloy, and is obtained by processing a lead frame.

[0024] The lead group 30 includes a plurality of external terminals 31 for power and a plurality of external terminals 32 for control.

[0025] Each of the multiple external terminals 31 is arranged inside and outside the sealing resin 40, and is electrically connected to the main current path of the switching element 21. In the example shown in Fig. 1, there are seven external terminals 31. The seven external terminals 31 are the output terminals U, V, and W of the three half-bridge circuits, the positive DC terminal P, and the negative DC terminals N(U), N(V), and N(W).

[0026] The external terminal 31 serving as the positive DC terminal P is joined to the metal plate 62a of the insulating substrate 60 via a thermal fuse 70 by soldering or the like. The external terminal 31 serving as the output terminal U is joined to the metal plate 62b of the insulating substrate 60 by soldering or the like. The external terminal 31 serving as the output terminal V is joined to the metal plate 62c of the insulating substrate 60 by soldering or the like. The external terminal 31 serving as the output terminal W is joined to the metal plate 62d of the insulating substrate 60 by soldering or the like. The thermal fuse 70 will be described later with reference to FIG. 2.

[0027] Here, the three external terminals 31, which are output terminals U, V, and W, correspond to the three switching elements 21 on the metal plate 62a described above, and are electrically connected to the output electrodes of the corresponding switching elements 21 via bonding wires 51 of the wire group 50. Furthermore, the negative DC terminals N(U), N(V), and N(W) correspond to the three switching elements 21 on the metal plates 62b, 62c, and 62d described above, and are electrically connected to the output electrodes of the corresponding switching elements 21 via bonding wires 51 of the wire group 50.

[0028] Each of the plurality of external terminals 32 is arranged inside and outside the sealing resin 40, and is electrically connected to the control element 22 or the diode 23. In the example shown in FIG. 1, the number of external terminals 32 is 21, and the 21 external terminals 32 are connected to the gate power supply terminal V BU , V BV , V BW , reference potential terminal V S2U , V S2V , V S2W , signal input terminal UINH , V INH , W INH , signal power terminal V CCH , 2 common terminals COM, signal input terminal U INL , V INL , W INL , signal power terminal V CCL , the current detection terminal IS, two NC terminals, and two dummy terminals. Of the two dummy terminals, one is the signal power terminal V CCH The other dummy terminal is electrically connected to the common terminal COM. The NC terminal is used as a terminal for outputting a signal indicating the detection result of the temperature sensor 22a.

[0029] Here, the rear surfaces of the two control elements 22 are joined to one of the two common terminals COM via an insulating or conductive adhesive or the like. BU , V BV , V BW The backside of the diode 23 is bonded to each of the 21 external terminals 32 via a conductive adhesive or the like. BU , V BV , V BW The external terminals 32 excluding the above are electrically connected to the front surfaces of the two control elements 22 via bonding wires 53 of the wire group 50 .

[0030] The sealing resin 40 seals the multiple switching elements 21, the multiple control elements 22, the multiple diodes 23, and part of the lead group 30. Although not shown, a heat dissipation member such as a heat dissipation fin is joined by screws or the like to the back surface of the sealing resin 40. The heat dissipation member dissipates heat from the multiple switching elements 21 to the outside.

[0031] The sealing resin 40 is made of a resin composition containing a resin such as a thermosetting resin, such as an epoxy resin. The resin composition preferably contains an inorganic filler from the viewpoint of improving thermal conductivity. An example of the inorganic filler is a silica (SiO2) filler. If necessary, the surface of the inorganic filler is subjected to a surface treatment such as a coupling treatment.

[0032] Although not shown, the sealing resin 40 has a frame-shaped first portion formed by insert molding using, for example, a lead frame including the lead group 30 as an insert part, and a second portion filled inside the first portion. During manufacturing of the semiconductor module 10, for example, after molding the first portion, the insulating substrate 60 is placed inside the first portion with the multiple switching elements 21 mounted thereon, and then the wire group 50 is formed and then the second portion is formed.

[0033] 1-2. Thermal fuse FIG. 2 is a cross-sectional view of a portion of the semiconductor module 10 according to the embodiment. FIG. 3 is a plan view illustrating the arrangement of the thermal fuse 70. FIG. 2 illustrates the connection between the external terminal 31, which is the positive DC terminal P, of the multiple external terminals 31 of the semiconductor module 10 and the insulating substrate 60. Note that in FIG. 2, only the outer edge of the sealing resin 40 is simply indicated by a two-dot chain line. Also, FIG. 3 illustrates the configuration on the metal plate 62a of the semiconductor module 10, but for ease of explanation, the wire group 50 is not illustrated.

[0034] Of the multiple external terminals 31, the external terminal 31 used as the positive DC terminal P is electrically connected to the metal plate 62a of the insulating substrate 60 via a thermal fuse 70, as shown in Fig. 2. The sealing resin 40 covers the multiple switching elements 21, the thermal fuse 70, the metal plate 62a, and a part of the external terminal 31 (positive DC terminal P).

[0035] In the example shown in FIG. 2, the thermal fuse 70 is plate-shaped with its thickness along the Z axis. A surface of the thermal fuse 70 facing the Z1 direction, of the external terminal 31 used as the positive DC terminal P, facing the Z2 direction, is joined via a conductive bonding material such as solder. Meanwhile, a surface of the metal plate 62a facing the Z1 direction is joined via a conductive bonding material such as solder to the surface of the thermal fuse 70 facing the Z2 direction. In this way, the thermal fuse 70 is joined onto one surface of the metal plate 62a. Furthermore, the external terminal 31 used as the positive DC terminal P is joined to the thermal fuse 70, thereby electrically connecting it to multiple switching elements 21 on the high-potential side.

[0036] The thermal fuse 70 is an overcurrent protection element that cuts off conduction when a predetermined temperature is reached, thereby protecting the multiple switching elements 21 on the high potential side from overheating.

[0037] Here, as described above, the thermal fuse 70 is bonded to the same metal plate 62a as the multiple high-potential side switching elements 21, so the thermal fuse 70 can be operated with high precision in response to the temperatures of these switching elements 21. Furthermore, the external terminal 31 (positive DC terminal P) and the multiple high-potential side switching elements 21 are electrically connected via the thermal fuse 70 and the metal plate 62a, so the operation of the multiple switching elements 21 can be stopped collectively by the operation of the thermal fuse 70. Furthermore, the positional relationship between the metal plate 62a and the external terminal 31 (positive DC terminal P) is fixed by the sealing resin 40, so that the electrical insulation state between the external terminal 31 (positive DC terminal P) and the metal plate 62a can be stably maintained after the thermal fuse 70 is activated. From the above, excessive temperature rise of the semiconductor module 10 can be effectively prevented.

[0038] The operating temperature of the thermal fuse 70 is lower than the thermal decomposition temperature of the sealing resin 40. This allows the thermal fuse 70 to operate before the sealing resin 40 is thermally decomposed. This prevents unintended conduction due to carbonization after the sealing resin 40 is thermally decomposed. As a result, even after the thermal fuse 70 operates, the sealing resin 40 maintains the fixed positional relationship between the metal plate 62a and the external terminal 31 (positive DC terminal P), and the sealing resin 40 also maintains an electrically insulating state.

[0039] From a similar perspective, the operating temperature of the thermal fuse 70 is preferably lower than the thermal decomposition temperature of the resin composition of the insulating plate 61. This allows the thermal fuse to operate before the resin composition of the insulating plate 61 is thermally decomposed. This prevents unintended conduction due to carbonization after thermal decomposition of the insulating plate 61. The specific operating temperature of the thermal fuse 70 is determined depending on the types of resins used for the sealing resin 40 and the insulating plate 61, and is not particularly limited, but is, for example, within the range of 180°C to 220°C.

[0040] As shown in FIG. 3, the distance L1 between the center P1 of the set S of multiple high-potential side switching elements 21 and the thermal fuse 70 is shorter than the distance L2 between the end E of the set S in the longitudinal direction and the thermal fuse 70. This reduces the variation in the distance between the high-potential side switching elements 21 and the thermal fuse 70 for each switching element 21. This allows the thermal fuse 70 to operate with high precision in accordance with the temperature of each high-potential side switching element 21. In this embodiment, the multiple high-potential side switching elements 21 are aligned in the direction along the X-axis, and the longitudinal direction of the set S is the direction along the X-axis.

[0041] The multiple switching elements 21 correspond to different phases and are therefore driven and controlled independently of one another. Therefore, by operating the thermal fuse 70, an excessive temperature rise in the multiple semiconductor modules 10 of different phases can be suitably prevented.

[0042] The thermal fuse 70 may be a non-resettable thermal fuse or a resettable thermal fuse.

[0043] A non-resettable thermal fuse is a thermal fuse having a conductor that melts and cuts off electrical continuity when it reaches its operating temperature. When the thermal fuse 70 is a non-resettable type, unintended electrical continuity can be more reliably prevented after the thermal fuse 70 has been activated.

[0044] On the other hand, a resettable thermal fuse is an element that cuts off conduction when a predetermined temperature is reached, but restores conduction when the temperature drops below the predetermined temperature, even after the predetermined temperature has been reached. When the thermal fuse 70 is resettable, if there are no abnormalities in the components of the semiconductor module 10 after the thermal fuse 70 has operated, the semiconductor module 10 can be restored without replacing the thermal fuse 70.

[0045] An example of a resettable thermal fuse is a polyswitch. A polyswitch includes a molded body containing conductive particles such as carbon or nickel and a resin, and restricts conduction by reducing contact between the conductive particles due to the expansion of the resin as the temperature rises. Even after reaching a predetermined temperature, a polyswitch returns to its original state when cooled due to the contraction of the resin. Note that resettable thermal fuses are not limited to polyswitches, and include, for example, a polyswitch whose resistance value increases due to a phase transition above a predetermined temperature (V 1-X Cr X The element may be made of a material such as a conductive metal oxide such as .2O3.

[0046] 1-3. Application examples of semiconductor modules 4 is a circuit diagram showing an application example of the semiconductor module 10 according to the embodiment. In the example shown in FIG. 4, the semiconductor module 10 includes a motor M and a DC power supply V DC The current detection resistor Rdet, power supply capacitors CB(U), CB(V), and CB(W), a signal power supply Vcc, and the controller 90 are connected.

[0047] The motor M is a three-phase motor and is connected to the output terminals U, V, and W of the three half-bridge circuits mentioned above. DC The positive poles of the DC power supply V are connected to the positive DC terminals P of the three half-bridge circuits. DC The negative poles of the positive and negative DC terminals N(U), N(V), and N(W) of the three half-bridge circuits are connected to the negative DC terminals N(U), N(V), and N(W) of the three half-bridge circuits via the current detection resistors Rdet. With the above connections, the semiconductor module 10 is connected to the DC power supply V via the positive DC terminal P and the negative DC terminals N(U), N(V), and N(W). DC It receives DC power from the inverter and supplies power to the motor M via output terminals U, V, and W.

[0048] The power supply capacitors CB(U), CB(V), and CB(W) are used as gate drive power supplies for the three high-potential side switching elements 21. Here, one of the pair of terminals of the power supply capacitor CB(U) is connected to the gate power supply terminal V BU and the other terminal is connected to the reference potential terminal V S2U Similarly, one of the pair of terminals of the power supply capacitor CB(V) is connected to the gate power supply terminal V BV and the other terminal is connected to the reference potential terminal V S2V One of the pair of terminals of the power supply capacitor CB(W) is connected to the gate power supply terminal V BW and the other terminal is connected to the reference potential terminal V S2W is connected to.

[0049] The positive terminal of the signal power supply Vcc is connected to the signal power supply terminal V CCH and signal power supply terminal V CCL On the other hand, the negative terminal of the signal power supply Vcc is connected to the common terminal COM and the ground terminal (GND) of the controller 90. CCH and the gate power supply terminal V BU , V BV , V BW and the signal power terminal V CCHThe anode is connected to the signal power supply V CC The power supply capacitors CB(U), CB(V), and CB(W) are charged by the power from

[0050] The controller 90 is an integrated arithmetic unit (MPU: Micro Processing Unit) for PWM (pulse width modulation) control. INH , V INH , W INH , common terminal COM, signal input terminal U INL , V INL , W INL and connected to the current detection terminal IS.

[0051] The controller 90 is connected to the signal input terminal U. INH , V INH , W INH and signal input terminal U INL , V INL , W INL Outputs the PWM signal input to each of the signal input terminals. INH , V INH , W INH The PWM signal input to the signal input terminal U is input to the control element 22 on the high potential side. INL , V INL , W INL The PWM signal input to the output terminal U is input to the control element 22 on the low potential side. Based on the input PWM signal, the control element 22 outputs a signal that changes the gate potential of the corresponding three switching elements 21 to the output terminal U. OUT ,V OUT ,W OUT As a result, the switching element of the switching element 21 is switched on and off based on the PWM signal from the controller 90.

[0052] The semiconductor module 10 detects the current flowing through each phase of the three half-bridge circuits based on the resistance value of the current detection resistor Rdet, and has the function of protecting the semiconductor module 10 from damage when an overcurrent occurs. A current level signal corresponding to changes in the resistance value of the current detection resistor Rdet is input to the low-potential side control element 22 via the current detection terminal IS and also input to the controller 90. The low-potential side control element 22 determines whether an overcurrent has occurred based on the results of comparing the current level signal with a reference value, and if an overcurrent has occurred, shuts off the current in the low-potential side switching element 21. The controller 90 also determines whether an overcurrent has occurred based on the results of comparing the current level signal with a reference value, and if an overcurrent has occurred, shuts off the current in the high-potential side switching element 21.

[0053] Furthermore, in the semiconductor module 10, as described above, a thermal fuse 70 is interposed between the positive DC terminal P and the three switching elements on the high potential side, and when the operating temperature is reached, the thermal fuse 70 cuts off the current to all of the switching elements 21 on the high potential side.

[0054] Furthermore, when the temperature detected by the temperature sensor 22a reaches a predetermined temperature, the control element 22 on the low potential side also collectively cuts off the current to the switching elements 21 on the high potential side.

[0055] Specifically, when the temperature detected by the temperature sensor 22a reaches a predetermined temperature, the low-potential side control element 22 cuts off the power supply to the multiple switching elements 21 on the low-potential side. In addition, the low-potential side control element 22 shuts down the system by outputting an FO alarm signal to the controller 90. The predetermined temperature is lower than the operating temperature of the thermal fuse 70. As a result, if the control element 22 can operate normally, the thermal fuse 70 is not activated, and an overheating of the semiconductor module 10 can be prevented. Furthermore, even if the control element 22 cannot operate normally due to some problem, the operation of the thermal fuse 70 can prevent an overheating of the semiconductor module 10.

[0056] 2. Variations The present disclosure is not limited to the above-described embodiments, and various modifications are possible as described below. Furthermore, the embodiments and modifications may be combined as appropriate.

[0057] 2-1. Variation 1 In the above-described embodiment, the thermal fuse 70 is disposed on the metal plate 62a, but the present invention is not limited to this. For example, the thermal fuse 70 may be bonded to at least one of the metal plates 62b, 62c, and 62d. In other words, the external terminal 31 using the thermal fuse 70 is not limited to the positive DC terminal P, and may be, for example, the external terminal 31 used as the output terminals U, V, and W.

[0058] Furthermore, the number of thermal fuses 70 is not limited to one, but may be two or more.

[0059] 2-2. Variation 2 In addition, in the above-described embodiment, an example in which the insulating plate 61 and the conductive plate 63 are used is illustrated, but the present invention is not limited to this example, and for example, the insulating plate 61 and the conductive plate 63 may be omitted. In this case, for example, the thickness of the conductive pattern 62 may be thicker than that shown in the above-described drawings.

[0060] 2-3. Variation 3 In the above-described embodiment, the temperature sensor 22a is built into the control element 22, but the temperature sensor 22a may be configured as a separate element from the control element 22. In this case, the temperature sensor 22a may be located anywhere within the semiconductor module 10, for example, on the insulating substrate 60. The temperature sensor 22a is not limited to an IC temperature sensor and may be a temperature detection element such as a thermocouple, an RTD (Resistance Temperature Detector), or a thermistor. Furthermore, the number of temperature sensors 22a may be multiple. For example, the temperature sensor 22a may be built into each of the two control elements 22, or the temperature sensors 22a may be located at multiple positions on the insulating substrate 60.

[0061] Furthermore, the configuration for interrupting the current to the switching element 21 by the temperature sensor 22a is provided as needed, and may be omitted.

[0062] 3. Notes For example, the following aspects can be understood from the above embodiment and modified examples.

[0063] (Appendix 1) A first aspect, which is a preferred example of a semiconductor module of the present disclosure, comprises a metal plate, a plurality of switching elements bonded to one side of the metal plate, a temperature fuse bonded to one side of the metal plate, and an external terminal bonded to the temperature fuse and thereby electrically connected to the plurality of switching elements.

[0064] In the above-described embodiment, the thermal fuse is bonded to the same metal plate as the multiple switching elements, allowing the thermal fuse to operate with high precision in response to the temperatures of the switching elements. Furthermore, the external terminals and the multiple switching elements are electrically connected via the thermal fuse and the metal plate, allowing the operation of the multiple switching elements to be stopped collectively. This effectively prevents the semiconductor module from overheating.

[0065] (Note 2) In a second aspect, which is a preferred example of the first aspect, an insulating substrate for mounting the plurality of switching elements is further provided, the insulating substrate having an insulating plate and a conductor pattern disposed on one surface of the insulating plate, the conductor pattern including the metal plate. In this aspect, the metal plate can be easily installed at a desired position during manufacturing of the semiconductor module 10.

[0066] (Supplementary Note 3) In a third aspect, which is a preferred example of the second aspect, the insulating plate is made of a resin composition. In this aspect, the insulating plate is more likely to be damaged by excessive heating than in an aspect in which the insulating plate is made of ceramics. Therefore, the effect of preventing excessive heating of the semiconductor module is significant.

[0067] (Appendix 4) In a fourth aspect, which is a preferred example of the third aspect, the operating temperature of the thermal fuse is lower than the thermal decomposition temperature of the resin composition. In this aspect, the thermal fuse can be activated before the resin composition of the insulating plate is thermally decomposed. This makes it possible to prevent unintended conduction due to carbonization after thermal decomposition of the insulating plate.

[0068] (Appendix 5) In a fifth aspect, which is a preferred example of any of the first to fourth aspects, the distance between the center of the group of multiple switching elements and the thermal fuse is shorter than the distance between the longitudinal end of the group and the thermal fuse. In this aspect, it is possible to reduce the variation in the distance between each switching element and the thermal fuse. This allows the thermal fuse to operate with high precision according to the temperature of each switching element. It is also possible to prevent delays in disconnection when the temperature rises.

[0069] (Supplementary Note 6) In a sixth aspect which is a preferred example of any one of the first to fifth aspects, the plurality of switching elements are driven and controlled independently of one another. In the above aspect, by operating a thermal fuse, an excessive temperature rise in a plurality of semiconductor modules of different phases is preferably prevented.

[0070] (Supplementary Note 7) In a seventh aspect which is a preferred example of any of the first to sixth aspects, the thermal fuse is a non-reset type. In this aspect, unintended conduction can be more reliably prevented after the thermal fuse is activated.

[0071] (Appendix 8) In an eighth aspect which is a preferred example of any of the first to sixth aspects, the thermal fuse is a resettable type. In the above aspect, if there is no abnormality in any part of the semiconductor module after the thermal fuse has been activated, the semiconductor module can be restored without replacing the thermal fuse.

[0072] (Supplementary Note 9) In a ninth aspect, which is a preferred example of any one of the first to eighth aspects, a sealing resin is further provided to cover the plurality of switching elements, the thermal fuse, the metal plate, and a part of the external terminal. In the above aspect, the positional relationship between the metal plate and the external terminal is fixed by the sealing resin, so that the electrical insulation state between the external terminal and the metal plate can be stably maintained after the thermal fuse is activated.

[0073] (Appendix 10) In the tenth aspect, which is a preferred example of the ninth aspect, the operating temperature of the thermal fuse is lower than the thermal decomposition temperature of the sealing resin. In this aspect, the thermal fuse can be operated before the sealing resin is thermally decomposed. This makes it possible to prevent unintended conduction due to carbonization after the sealing resin is thermally decomposed. As a result, even after the thermal fuse is operated, the sealing resin can suitably maintain the fixed positional relationship between the metal plate and the external terminal, and the sealing resin can suitably maintain the electrical insulation state.

[0074] (Supplementary Note 11) In an eleventh aspect, which is a preferred example of any of the first to tenth aspects, the semiconductor module further includes a temperature sensor and a control element that cuts off current to the plurality of switching elements when the temperature detected by the temperature sensor reaches a predetermined temperature that is lower than the operating temperature of the thermal fuse. In the above aspect, if the control element can operate normally, the semiconductor module can be prevented from overheating without operating the thermal fuse. Furthermore, even if the control element cannot operate normally due to some problem, the semiconductor module can be prevented from overheating by operating the thermal fuse. [Explanation of symbols]

[0075] 10...semiconductor module, 21...switching element, 22...control element, 22a...temperature sensor, 23...diode, 30...lead group, 31...external terminal, 32...external terminal, 40...encapsulating resin, 50...wire group, 51...bonding wire, 52...bonding wire, 53...bonding wire, 54...bonding wire, 60...insulating substrate, 61...insulating plate, 62...conductor pattern, 62a...metal plate, 62b...metal plate, 62c...metal plate, 62d...metal plate, 63...conductor plate, 70...thermal fuse, 90...controller, CB(U), CB(V), CB(W)...power supply capacitor, COM...common terminal, E...end, IS...current detection terminal, L1...distance, L2...distance, M...motor, N(U), N(V), N(W)...negative DC terminal, P...positive DC terminal, P1...center, R det ...Current detection resistor, S...Collective, U...Output terminal, U INH …Signal input terminal, U INL …Signal input terminal, U OUT …output terminal, V…output terminal, V BU …Gate power supply terminal, V BV …Gate power supply terminal, V BW …Gate power supply terminal, V CC …Signal power supply, V CCH …Signal power supply terminal, V CCL …Signal power supply terminal, V DC …DC power supply, V INH …Signal input terminal, V INL …Signal input terminal, V OUT …output terminal, V S2U ...Reference potential terminal, V S2V ...Reference potential terminal, V S2W ...Reference potential terminal, V cc …Signal power supply, W…Output terminal, W INH …Signal input terminal, W INL …Signal input terminal, W OUT ...Output terminal.

Claims

1. A metal plate; a plurality of switching elements bonded to one surface of the metal plate; a thermal fuse bonded to one surface of the metal plate; an external terminal joined to the thermal fuse to be electrically connected to the plurality of switching elements; Semiconductor module.

2. further comprising an insulating substrate for mounting the plurality of switching elements; The insulating substrate is An insulating plate; a conductor pattern disposed on one surface of the insulating plate, The conductor pattern includes the metal plate. The semiconductor module according to claim 1 .

3. The insulating board is made of a resin composition. The semiconductor module according to claim 2 .

4. The operating temperature of the thermal fuse is lower than the thermal decomposition temperature of the resin composition. The semiconductor module according to claim 3 .

5. a distance between a center of the group of the plurality of switching elements and the thermal fuse is shorter than a distance between an end of the group in the longitudinal direction and the thermal fuse; The semiconductor module according to claim 1 .

6. The plurality of switching elements are driven and controlled independently of each other. The semiconductor module according to claim 1 .

7. The thermal fuse is a non-resettable type. The semiconductor module according to claim 1 .

8. The thermal fuse is a reset type. The semiconductor module according to claim 1 .

9. a sealing resin that covers the plurality of switching elements, the thermal fuse, the metal plate, and a part of the external terminal; The semiconductor module according to claim 1 .

10. The operating temperature of the thermal fuse is lower than the thermal decomposition temperature of the sealing resin. The semiconductor module according to claim 9 .

11. A temperature sensor; a control element that cuts off current to the plurality of switching elements when the temperature detected by the temperature sensor reaches a predetermined temperature that is lower than the operating temperature of the thermal fuse. The semiconductor module according to claim 1 .

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