Power module, electronic device, and power conversion device

Abstract

A power module (1) comprises: an electronic circuit board (3); a conductive bridge connection member (20); and an external connection terminal (21) connected to the bridge connection member (20). The electronic circuit board (3) includes an insulating circuit board (10), and at least one power semiconductor element (14a, 14b) mounted on the insulating circuit board (10). The bridge connection member (20) is connected to a first portion of the electronic circuit board (3) and to a second portion of the electronic circuit board (3). A linear expansion coefficient of the bridge connection member (20) is between a linear expansion coefficient of the insulating circuit board (10) and a linear expansion coefficient of the external connection terminal (21).

Description

Power module, electronic device and power conversion device

[0001] The present disclosure relates to a power module, an electronic device, and a power conversion device.

[0002] Japanese Patent No. 5793995 (Patent Document 1) discloses a power module including a heat spreader, an insulated gate bipolar transistor (IGBT), a diode, and a power lead portion. The IGBT and the diode are soldered to the heat spreader. The power lead portion is soldered to the IGBT and the diode.

[0003] Patent No. 5793995

[0004] An object of the present disclosure is to provide a power module, an electronic device, and a power conversion device with improved reliability.

[0005] The power module of the present disclosure includes an electronic circuit board, a conductive bridge connection member, and external connection terminals connected to the bridge connection member. The electronic circuit board includes an insulating circuit board and at least one power semiconductor element mounted on the insulating circuit board. The insulating circuit board includes an insulating layer having a main surface and a circuit pattern layer disposed on the main surface. The bridge connection member is connected to a first portion of the electronic circuit board and a second portion of the electronic circuit board. The linear expansion coefficient of the bridge connection member is between the linear expansion coefficients of the insulating circuit board and the external connection terminals.

[0006] The electronic device of the present disclosure includes a cooler, a thermal interface material, and a power module of the present disclosure attached to the cooler via the thermal interface material.

[0007] The power conversion device of the present disclosure includes a power module of the present disclosure, a main conversion circuit that converts input power and outputs it, and a control circuit that outputs a control signal to the main conversion circuit to control the main conversion circuit.

[0008] According to the present disclosure, a power module, an electronic device, and a power conversion device with improved reliability are provided.

[0009] 1. A schematic, partially enlarged plan view of a power module and an electronic device according to a first embodiment. A schematic, partially enlarged cross-sectional view of the power module and the electronic device according to the first embodiment, taken along the cross-sectional line II-II shown in FIG. 1. A schematic, partially enlarged plan view of a power module and an electronic device according to a comparative example. A schematic, partially enlarged cross-sectional view of the power module and the electronic device according to the comparative example, taken along the cross-sectional line IV-IV shown in FIG. 3. A schematic, partially enlarged plan view of a power module and an electronic device according to a second embodiment. A schematic, partially enlarged cross-sectional view of the power module and the electronic device according to the second embodiment, taken along the cross-sectional line VI-VI shown in FIG. 5. A circuit diagram of a power module and an electronic device according to a third embodiment. A schematic, partially enlarged plan view of a power module and an electronic device according to a third embodiment. A schematic, partially enlarged cross-sectional view of the power module and the electronic device according to the third embodiment, taken along the cross-sectional line IX-IX shown in FIG. 8. A schematic, partially enlarged cross-sectional view of the power module and the electronic device according to the third embodiment, taken along the cross-sectional line X-X shown in FIG. 8. A schematic, partially enlarged plan view of a power module and an electronic device according to a fourth embodiment. A schematic, partially enlarged cross-sectional view of the power module and the electronic device according to the fourth embodiment, taken along the cross-sectional line XII-XII shown in FIG. 16 is a schematic partial enlarged plan view of a power module and electronic device according to a first modified example of embodiment 4. FIG. 17 is a schematic partial enlarged plan view of a power module and electronic device according to a second modified example of embodiment 4. FIG. 18 is a schematic partial enlarged plan view of a power module and electronic device according to a fifth embodiment. FIG. 19 is a schematic partial enlarged cross-sectional view of the power module and electronic device according to the fifth embodiment, taken along the cross-sectional line XVI-XVI shown in FIG. 15 . FIG. 19 is a schematic partial enlarged plan view of a power module and electronic device according to a first modified example of embodiment 5. FIG. 19 is a schematic partial enlarged plan view of a power module and electronic device according to a second modified example of embodiment 5. FIG. 20 is a schematic partial enlarged cross-sectional view of a power module and electronic device according to a third modified example of embodiment 5. FIG. 21 is a schematic partial enlarged cross-sectional view of a power module and electronic device according to a sixth embodiment. FIG. 22 is a block diagram showing the configuration of a power conversion system according to a seventh embodiment.

[0010] Hereinafter, embodiments of the present disclosure will be described. Note that the same reference numerals are used to designate the same components, and the description thereof will not be repeated.

[0011] 1 and 2, a power module 1 according to a first embodiment will be described. The power module 1 mainly comprises an electronic circuit board 3, a bridge connection member 20, external connection terminals 21, and a sealing member 30. The electronic circuit board 3 includes an insulating circuit board 10 and at least one power semiconductor element (e.g., power semiconductor elements 14a, 14b).

[0012] The insulating circuit board 10 includes an insulating layer 11 , a circuit pattern layer 12 , and a conductive pattern layer 13 .

[0013] The insulating layer 11 has a main surface 11a and a main surface 11b opposite to the main surface 11a. The insulating layer 11 is, for example, a ceramic layer or a resin sheet. When the insulating layer 11 is a ceramic layer, the insulating layer 11 is, for example, alumina (Al ２ O ３ ), aluminum nitride (AlN) or silicon nitride (Si ３ N ４ ) are made of ceramics such as

[0014] The circuit pattern layer 12 is disposed on the main surface 11a. The conductive pattern layer 13 is disposed on the main surface 11b. The surface 13a of the conductive pattern layer 13 opposite the insulating layer 11 is a mounting surface for the cooler 33 and is also a surface on which the thermal interface material 32 is provided. The circuit pattern layer 12 and the conductive pattern layer 13 are formed of a metal such as copper (Cu) or aluminum (Al). The insulating circuit board 10 is, for example, a DBC (Direct Bonded Copper) substrate in which a copper layer is bonded to a ceramic substrate.

[0015] In this embodiment, the at least one power semiconductor element includes a power semiconductor element 14 a and a power semiconductor element 14 b. The power semiconductor elements 14 a and 14 b are, for example, switching elements such as insulated gate bipolar transistors (IGBTs) or metal oxide semiconductor field effect transistors (MOSFETs), or diodes such as freewheeling diodes. The power semiconductor elements 14 a and 14 b are mainly formed of a semiconductor material such as silicon (Si) or silicon carbide (SiC).

[0016] The power semiconductor elements 14a and 14b are mounted on the insulating circuit board 10. Specifically, the power semiconductor element 14a is joined to the circuit pattern layer 12 using a conductive bonding member 15a. The power semiconductor element 14b is joined to the circuit pattern layer 12 using a conductive bonding member 15b. The conductive bonding members 15a and 15b are, for example, solder or a sintered bonding member (for example, a metal fine particle sintered body such as a silver nanoparticle sintered body).

[0017] The bridge connection member 20 is electrically conductive. The bridge connection member 20 is formed of, for example, a copper-invar-copper clad material, an iron-nickel alloy, a copper-molybdenum composite material, a copper-molybdenum clad material, a copper-tungsten composite material, an aluminum-silicon carbide composite material, or a printed circuit board including an insulating substrate formed of a material having a linear expansion coefficient of less than 10 ppm / K (for example, glass epoxy). The bridge connection member 20 may have a width wider than the external connection terminals 21. The bridge connection member 20 may be formed of a material having a higher electrical resistivity than the external connection terminals 21.

[0018] The bridge connection member 20 includes a surface 20a facing the insulating circuit board 10 and a surface 20b opposite to surface 20a. The bridge connection member 20 includes an end 20i and an end 20j opposite end 20i. Ends 20i and 20j are, for example, both ends of the bridge connection member 20 in the longitudinal direction of the bridge connection member 20. At least a portion of the bridge connection member 20 extends above the insulating circuit board 10. In this embodiment, the entire bridge connection member 20 extends above the insulating circuit board 10.

[0019] The bridge connection member 20 is connected to a first portion of the electronic circuit board 3 and a second portion of the electronic circuit board 3. In this embodiment, the first portion of the electronic circuit board 3 is the power semiconductor element 14a. The second portion of the electronic circuit board 3 is the power semiconductor element 14b. For example, the bridge connection member 20 is joined to the power semiconductor element 14a using a conductive bonding member 16a. The bridge connection member 20 is joined to the power semiconductor element 14b using a conductive bonding member 16b. The conductive bonding members 16a and 16b are, for example, solder or a sintered bonding member (for example, a metal microparticle sintered body such as a silver nanoparticle sintered body). The conductive bonding members 16a and 16b are in contact with a surface 20a of the bridge connection member 20.

[0020] In a plan view of the main surface 11a of the insulating layer 11, the bridge connection member 20 may be disposed inside the insulating circuit board 10. In a plan view of the main surface 11a of the insulating layer 11, the ends 20i and 20j of the bridge connection member 20 may be disposed inside the insulating circuit board 10. In a plan view of the main surface 11a of the insulating layer 11, the bridge connection member 20 may be disposed inside the circuit pattern layer 12. In a plan view of the main surface 11a of the insulating layer 11, the ends 20i and 20j of the bridge connection member 20 may be disposed inside the circuit pattern layer 12. In a plan view of the main surface 11a of the insulating layer 11, the end 20i of the bridge connection member 20 may overlap a first portion of the electronic circuit board 3, and the end 20j of the bridge connection member 20 may overlap a second portion of the electronic circuit board 3. The linear expansion coefficient of the bridge connection member 20 is between the linear expansion coefficients of the insulating circuit board 10 and the external connection terminals 21. The linear expansion coefficient of the bridge connection member 20 is between the linear expansion coefficient of the insulating layer 11 and the linear expansion coefficient of the external connection terminal 21 .

[0021] The external connection terminals 21 are connected to the bridge connection member 20 by a conductive joining member (not shown) such as solder, or by welding such as ultrasonic welding or laser welding. The external connection terminals 21 are connected to the surface 20b of the bridge connection member 20 via a conductive joining member (not shown) or directly. The external connection terminals 21 are conductive. The external connection terminals 21 extend to the outside of the sealing member 30. For example, a current or a voltage may be input to the power module 1 from outside the power module 1 through the external connection terminals 21. A current or a voltage may be output from the power module 1 to the outside of the power module 1 through the external connection terminals 21.

[0022] The sealing member 30 seals at least one power semiconductor element (power semiconductor elements 14 a, 14 b in this embodiment) and at least a portion of the insulating circuit board 10. The sealing member 30 has insulating properties and is formed of, for example, a thermosetting resin such as an epoxy resin or a gel-like resin such as a silicone gel.

[0023] An electronic device 2 according to the present embodiment will be described with reference to Figures 1 and 2. The electronic device 2 includes the power module 1 according to the present embodiment, a thermal interface material (TIM) 32, and a cooler 33.

[0024] The thermal interface material 32 is disposed between the insulating circuit board 10 and the cooler 33. Specifically, the thermal interface material 32 is disposed between the surface 13a of the conductive pattern layer 13 and the cooler 33. The thermal interface material 32 is, for example, a grease such as silicone grease. The thermal interface material 32 has, for example, a thermal conductivity of 1.0 W / (m·K) or more. The thermal conductivity of the thermal interface material 32 may be 3.0 W / (m·K) or more, or may be 5.0 W / (m·K) or more.

[0025] The cooler 33 is, for example, a heat sink. The cooler 33 is made of a metal such as aluminum (Al) or copper (Cu), or an alloy such as an aluminum alloy. The cooler 33 dissipates heat from the power module 1 to the outside of the electronic device 2. The power module 1 is attached to the cooler 33 via a thermal interface material 32.

[0026] An example of a method for manufacturing the power module 1 and electronic device 2 of this embodiment will be described. Power semiconductor elements 14a, 14b are mounted on the insulating circuit board 10. Specifically, the power semiconductor element 14a is bonded to the circuit pattern layer 12 using a conductive bonding member 15a. The power semiconductor element 14b is bonded to the circuit pattern layer 12 using a conductive bonding member 15b. In this manner, the electronic circuit board 3 is obtained.

[0027] A bridge connection member 20 is connected to the first and second portions of the electronic circuit board 3. For example, the bridge connection member 20 is joined to the power semiconductor element 14a using a conductive bonding member 16a. The bridge connection member 20 is joined to the power semiconductor element 14b using a conductive bonding member 16b. In this embodiment, the first portion of the electronic circuit board 3 is the power semiconductor element 14a, and the second portion of the electronic circuit board 3 is the power semiconductor element 14b.

[0028] The external connection terminals 21 are connected to the bridge connection member 20 by a conductive joining member (not shown) such as solder, or by welding such as ultrasonic welding or laser welding.

[0029] A sealing member 30 is provided on the electronic circuit board 3. For example, when the sealing member 30 is formed from a thermosetting resin such as an epoxy resin, the sealing member 30 is provided on the electronic circuit board 3 by transfer molding, injection molding, or the like. The sealing member 30 seals the power semiconductor elements 14a, 14b and at least a portion of the insulating circuit board 10. The external connection terminals 21 extend outside the sealing member 30. In this manner, the power module 1 is obtained.

[0030] Then, the power module 1 is attached to the cooler 33 via the thermal interface material 32. The thermal interface material 32 is disposed between the insulating circuit board 10 and the cooler 33. In this way, the electronic device 2 is obtained.

[0031] The operation of the power module 1 and electronic device 2 of this embodiment shown in FIGS. 1 and 2 will be described below in comparison with a power module 1a and electronic device 2a of a comparative example shown in FIGS.

[0032] The power module 1a and electronic device 2a of the comparative example are configured similarly to the power module 1 and electronic device 2 of the present embodiment, but differ from the power module 1 and electronic device 2 of the present embodiment in the following respects: The power module 1a and electronic device 2a of the comparative example do not have the bridge connection member 20, and the external connection terminals 21 are joined to the power semiconductor elements 14a and 14b using conductive joining members 16a and 16b.

[0033] In the comparative example, the external connection terminals 21 are joined to the power semiconductor elements 14a, 14b using conductive bonding members 16a, 16b. The difference between the linear expansion coefficient of the external connection terminals 21 and the linear expansion coefficient of the insulating circuit board 10 is large. For example, if the external connection terminals 21 are made of copper (Cu), the linear expansion coefficient of the external connection terminals 21 is, for example, approximately 17 ppm / K. If the insulating circuit board 10 is a DBC substrate, the linear expansion coefficient of the insulating circuit board 10 is, for example, approximately 5 ppm / K. Therefore, the thermal stress applied to the insulating layer 11 during operation of the power module 1a of the comparative example is large, and cracks may occur in the insulating layer 11. As a result, the reliability of the power module 1a and electronic device 2a of the comparative example is insufficient.

[0034] Furthermore, in the comparative example, the difference between the linear expansion coefficient of the external connection terminals 21 and the linear expansion coefficient of the insulating circuit board 10 is large, causing the insulating layer 11 to warp significantly during operation of the power module 1a. When the power module 1a is repeatedly switched between the on and off states and temperature cycles are repeatedly applied to the power module 1a and the electronic device 2, the insulating layer 11 undergoes repeated thermal deformation between a large warpage state and a small warpage state. The insulating circuit board 10, including the insulating layer 11, also undergoes repeated thermal deformation between a large warpage state and a small warpage state. Due to the repeated thermal deformation of the insulating circuit board 10, a portion of the thermal interface material 32 is pumped outward in a plan view of the main surface 11a (see FIG. 3). Therefore, a void 32a (see FIG. 4) is generated between the insulating circuit board 10 and the cooler 33, increasing the thermal resistance between the insulating circuit board 10 and the cooler 33. This makes it difficult for heat from the power module 1a to dissipate to the cooler 33, making the power module 1a more susceptible to thermal damage. The reliability of the power module 1a and the electronic device 2 is reduced.

[0035] In contrast, in the present embodiment, the external connection terminals 21 are joined to the insulating circuit board 10 via bridge connection members 20. The linear expansion coefficient of the bridge connection members 20 is between the linear expansion coefficients of the insulating circuit board 10 and the external connection terminals 21. This reduces the thermal stress applied to the insulating layer 11 during operation of the power module 1, thereby suppressing the occurrence of cracks in the insulating layer 11. The reliability of the power module 1 and the electronic device 2 of this embodiment is improved.

[0036] Furthermore, in this embodiment, the linear expansion coefficient of the bridge connection member 20 is between the linear expansion coefficient of the insulating circuit board 10 and the linear expansion coefficient of the external connection terminal 21, thereby reducing warping of the insulating layer 11 during operation of the power module 1. Pump-out of the thermal interface material 32 caused by repeated thermal deformation of the insulating circuit board 10 is suppressed. This prevents voids from occurring between the insulating circuit board 10 and the cooler 33, thereby suppressing an increase in thermal resistance between the insulating circuit board 10 and the cooler 33. Heat from the power module 1 is efficiently dissipated to the cooler 33, making the power module 1 less susceptible to thermal damage. The reliability of the power module 1 and the electronic device 2 is improved.

[0037] The effects of the power module 1 and electronic device 2 of this embodiment will be described. The power module 1 of this embodiment includes an electronic circuit board 3, a conductive bridge connection member 20, and external connection terminals 21 connected to the bridge connection member 20. The electronic circuit board 3 includes an insulating circuit board 10 and at least one power semiconductor element (e.g., power semiconductor elements 14a, 14b) mounted on the insulating circuit board 10. The insulating circuit board 10 includes an insulating layer 11 having a main surface 11a and a circuit pattern layer 12 disposed on the main surface 11a. The bridge connection member 20 is connected to a first portion of the electronic circuit board 3 and a second portion of the electronic circuit board 3. The linear expansion coefficient of the bridge connection member 20 is between the linear expansion coefficients of the insulating circuit board 10 and the external connection terminals 21.

[0038] This reduces the thermal stress applied to the insulating layer 11 during operation of the power module 1, thereby suppressing the occurrence of cracks in the insulating layer 11. The reliability of the power module 1 of this embodiment is improved.

[0039] Furthermore, warping of the insulating layer 11 during operation of the power module 1 is reduced. Pump-out of the thermal interface material 32 on the insulating circuit board 10, which is caused by repeated thermal deformation of the insulating circuit board 10, is suppressed. An increase in thermal resistance between the insulating circuit board 10 and the cooler 33 is suppressed, and heat from the power module 1 is efficiently dissipated to the cooler 33. The power module 1 is less susceptible to thermal damage, and the reliability of the power module 1 is improved.

[0040] In the power module 1 of this embodiment, at least one power semiconductor element (e.g., power semiconductor elements 14a, 14b) includes a first power semiconductor element (e.g., power semiconductor element 14a) bonded to the circuit pattern layer 12 and a second power semiconductor element (e.g., power semiconductor element 14b) bonded to the circuit pattern layer 12. The first portion of the electronic circuit board 3 is the first power semiconductor element. The second portion of the electronic circuit board 3 is the second power semiconductor element.

[0041] This prevents cracks from occurring in the insulating layer 11. It also prevents pump-out of the thermal interface material 32 caused by repeated thermal deformation of the insulating circuit board 10. This improves the reliability of the power module 1 of this embodiment.

[0042] In the power module 1 of this embodiment, the bridge connection member 20 includes a first end (end 20i) and a second end (end 20j) opposite the first end. In a plan view of the main surface 11a of the insulating layer 11, the first end of the bridge connection member 20 overlaps the first portion, and the second end of the bridge connection member 20 overlaps the second portion.

[0043] This reduces the size of the bridge connection member 20. The cost of the bridge connection member 20 is reduced, and the cost of the power module 1 is reduced.

[0044] In the power module 1 of this embodiment, the bridge connection member 20 is formed of a copper-invar-copper clad material, an iron-nickel alloy, a copper-molybdenum composite material, a copper-molybdenum clad material, a copper-tungsten composite material, an aluminum-silicon carbide composite material, or a printed circuit board.

[0045] This prevents cracks from occurring in the insulating layer 11. It also prevents pump-out of the thermal interface material 32 caused by repeated thermal deformation of the insulating circuit board 10. This improves the reliability of the power module 1 of this embodiment.

[0046] Furthermore, the power module 1 of this embodiment includes bridge connection members 20 and external connection terminals 21. Therefore, the length of the bridge connection members 20 can be made shorter than that of the external connection terminals 21. Even if the bridge connection members 20 are made of a material that is more expensive than the external connection terminals 21, an excessive increase in the cost of the power module 1 can be suppressed. Even if the bridge connection members 20 are made of a material that has a higher electrical resistivity than the external connection terminals 21, there is no need to excessively increase the width and thickness of the bridge connection members 20 in order to prevent a significant increase in the electrical resistance of the bridge connection members 20. Therefore, an increase in the size of the power module 1 is prevented.

[0047] The electronic device 2 of this embodiment includes the power module 1 of this embodiment, a thermal interface material 32, and a cooler 33. The power module 1 is attached to the cooler 33 via the thermal interface material 32.

[0048] This prevents cracks from occurring in the insulating layer 11. It also prevents pump-out of the thermal interface material 32 caused by repeated thermal deformation of the insulating circuit board 10. This improves the reliability of the electronic device 2 of this embodiment.

[0049] Second Embodiment A power module 1 and an electronic device 2 according to a second embodiment will be described with reference to Figures 5 and 6. The power module 1 and the electronic device 2 according to this embodiment have the same configurations and effects as the power module 1 and the electronic device 2 according to the first embodiment, but differ mainly in the following respects.

[0050] In this embodiment, the circuit pattern layer 12 includes a first circuit pattern partial layer 12a and a second circuit pattern partial layer 12b. The second circuit pattern partial layer 12b is spaced apart from the first circuit pattern partial layer 12a and electrically insulated from the first circuit pattern partial layer 12a. The at least one power semiconductor element is a power semiconductor element 14a. The power module 1 of this embodiment does not include the power semiconductor element 14b. The power semiconductor element 14a is bonded to the first circuit pattern partial layer 12a using a conductive bonding member 15a.

[0051] The bridge connection member 20 is connected to the power semiconductor element 14a and the circuit pattern layer 12 (second circuit pattern partial layer 12b). In other words, in this embodiment, the first portion of the electronic circuit board 3 to which the bridge connection member 20 is connected is the power semiconductor element 14a, and the second portion of the electronic circuit board 3 to which the bridge connection member 20 is connected is the circuit pattern layer 12 (second circuit pattern partial layer 12b).

[0052] Specifically, the bridge connection member 20 is bonded to the power semiconductor element 14a using a conductive bonding member 16a. The conductive bonding member 16a is in contact with a surface 20a of the bridge connection member 20. The bridge connection member 20 is bonded to the second circuit pattern partial layer 12b by a conductive bonding member (not shown) such as solder, or by welding such as ultrasonic welding or laser welding. The surface 20a of the bridge connection member 20 is connected to the second circuit pattern partial layer 12b via a conductive bonding member (not shown) or directly.

[0053] The power module 1 and the electronic device 2 of this embodiment have the following effects similar to those of the power module 1 and the electronic device 2 of the first embodiment.

[0054] In the power module 1 and the electronic device 2 of this embodiment, at least one power semiconductor element (e.g., the power semiconductor element 14a) includes a first power semiconductor element (e.g., the power semiconductor element 14a) bonded to the circuit pattern layer 12. The first portion of the electronic circuit board 3 is the first power semiconductor element. The second portion of the electronic circuit board 3 is the circuit pattern layer 12.

[0055] This prevents cracks from occurring in the insulating layer 11. It also prevents pump-out of the thermal interface material 32 caused by repeated thermal deformation of the insulating circuit board 10. This improves the reliability of the power module 1 and the electronic device 2 of this embodiment.

[0056] Third Embodiment The circuit configuration of a power module 1 according to a third embodiment will be described with reference to FIG.

[0057] The power module 1 of this embodiment further includes power semiconductor elements 14c and 14d. In this embodiment, at least one power semiconductor element is power semiconductor elements 14a, 14b, 14c, and 14d. The power semiconductor elements 14c and 14d are primarily formed of a semiconductor material such as silicon (Si) or silicon carbide (SiC). In this embodiment, the power semiconductor elements 14a and 14c are switching elements such as insulated gate bipolar transistors (IGBTs) or metal oxide semiconductor field effect transistors (MOSFETs). The power semiconductor elements 14b and 14d are diodes such as freewheeling diodes. The power module 1 of this embodiment is a 2-in-1 type power module including two pairs of semiconductor switching elements and diodes.

[0058] The power module 1 includes a positive terminal 17, a negative terminal 18, and an output terminal 19. The power semiconductor elements 14c and 14d form an upper arm of a bridge circuit. In the upper arm, the power semiconductor elements 14c and 14d are connected in anti-parallel to each other. The upper arm is connected to the positive terminal 17 and the output terminal 19. The power semiconductor elements 14a and 14b form a lower arm of the bridge circuit. In the lower arm, the power semiconductor elements 14a and 14b are connected in anti-parallel to each other. The lower arm is connected to the negative terminal 18 and the output terminal 19. The upper arm and the lower arm are connected in series to each other. The output terminal 19 is connected to a load (not shown), such as a motor.

[0059] The power module 1 and electronic device 2 of this embodiment will be described with reference to Figures 8 to 10. The power module 1 and electronic device 2 of this embodiment have the same configurations and effects as the power module 1 and electronic device 2 of embodiment 1, but differ mainly in the following respects.

[0060] In this embodiment, the circuit pattern layer 12 includes a first circuit pattern partial layer 12a and a second circuit pattern partial layer 12b spaced apart from the first circuit pattern partial layer 12a.

[0061] Power semiconductor elements 14a, 14b, 14c, and 14d are mounted on the insulating circuit board 10. Specifically, the power semiconductor element 14a is bonded to the first circuit pattern partial layer 12a using a conductive bonding member 15a. The power semiconductor element 14b is bonded to the first circuit pattern partial layer 12a using a conductive bonding member 15b. The power semiconductor element 14c is bonded to the second circuit pattern partial layer 12b using a conductive bonding member 15c. The power semiconductor element 14d is bonded to the second circuit pattern partial layer 12b using a conductive bonding member 15d. The conductive bonding members 15c and 15d are, for example, solder or a sintered bonding member (e.g., a metal microparticle sintered body such as a silver nanoparticle sintered body).

[0062] The power module 1 of this embodiment further includes a bridge connection member 25 and external connection terminals 26 and 29 .

[0063] The bridge connection member 25 is electrically conductive. The bridge connection member 25 is formed of, for example, a copper-invar-copper clad material, an iron-nickel alloy, a copper-molybdenum composite material, a copper-molybdenum clad material, a copper-tungsten composite material, an aluminum-silicon carbide composite material, or a printed circuit board including an insulating substrate formed of a material having a linear expansion coefficient of less than 10 ppm / K (for example, glass epoxy). The bridge connection member 25 may have a width greater than that of the external connection terminals 21, 26. The bridge connection member 25 may be formed of a material having a higher electrical resistivity than that of the external connection terminals 21, 26. The bridge connection member 25 may be formed of the same material as the bridge connection member 20, or may be formed of a different material.

[0064] The bridge connection member 25 includes a surface 25a facing the insulating circuit board 10 and a surface 25b opposite to surface 25a. The bridge connection member 25 includes an end 25i and an end 25j opposite end 25i. Ends 25i and 25j are, for example, both ends of the bridge connection member 25 in the longitudinal direction of the bridge connection member 25. A portion of the bridge connection member 25 extends above the insulating circuit board 10.

[0065] The bridge connection member 25 is connected to the power semiconductor element 14c, the power semiconductor element 14d, and the first circuit pattern partial layer 12a. For example, the bridge connection member 25 is joined to the power semiconductor element 14c using a conductive bonding member 16c. The bridge connection member 25 is joined to the power semiconductor element 14d using a conductive bonding member 16d. The conductive bonding members 16c, 16d are, for example, solder or a sintered bonding member (e.g., a metal microparticle sintered body such as a silver nanoparticle sintered body). The conductive bonding members 16c, 16d are in contact with a surface 25a of the bridge connection member 20.

[0066] The bridge connection member 25 is connected to the first circuit pattern portion layer 12a by a conductive joining member (not shown) such as solder, or by welding such as ultrasonic welding or laser welding. The surface 25a of the bridge connection member 20 is connected to the first circuit pattern portion layer 12a via a conductive joining member (not shown) or directly.

[0067] In a plan view of the main surface 11a of the insulating layer 11, the bridge connection member 25 may be disposed inside the insulating circuit board 10. In a plan view of the main surface 11a of the insulating layer 11, the ends 25i and 25j of the bridge connection member 25 may be disposed inside the insulating circuit board 10. In a plan view of the main surface 11a of the insulating layer 11, the bridge connection member 25 may be disposed inside the circuit pattern layer 12. In a plan view of the main surface 11a of the insulating layer 11, the ends 25i and 25j of the bridge connection member 25 may be disposed inside the circuit pattern layer 12. In a plan view of the main surface 11a of the insulating layer 11, the end 25i of the bridge connection member 25 may overlap the first circuit pattern partial layer 12a, and the end 25j of the bridge connection member 25 may overlap the power semiconductor element 14d. The linear expansion coefficient of the bridge connection member 25 is between the linear expansion coefficient of the insulating circuit board 10 and the linear expansion coefficient of the external connection terminal 26. The linear expansion coefficient of the bridge connection member 25 is between the linear expansion coefficient of the insulating layer 11 and the linear expansion coefficient of the external connection terminal 26 .

[0068] The external connection terminals 26 are connected to the bridge connection member 25 by a conductive joining member (not shown) such as solder, or by welding such as ultrasonic welding or laser welding. The external connection terminals 26 are connected to the surface 25b of the bridge connection member 25 via a conductive joining member (not shown) or directly. The external connection terminals 26 are conductive. The external connection terminals 26 extend to the outside of the sealing member 30. For example, a current or a voltage may be input to the power module 1 from outside the power module 1 through the external connection terminals 26. A current or a voltage may be output from the power module 1 to the outside of the power module 1 through the external connection terminals 26.

[0069] The external connection terminals 29 are connected to the circuit pattern layer 12 (second circuit pattern partial layer 12b) by a conductive joining member (not shown) such as solder, or by welding such as ultrasonic welding or laser welding. The external connection terminals 29 are conductive. The external connection terminals 29 extend above the first circuit pattern partial layer 12a to the outside of the sealing member 30. For example, a current or a voltage may be input to the power module 1 from outside the power module 1 through the external connection terminals 29. A current or a voltage may be output from the power module 1 to the outside of the power module 1 through the external connection terminals 29.

[0070] The electronic device 2 of this embodiment has a configuration similar to that of the electronic device 2 of embodiment 1, but differs from the electronic device 2 of embodiment 1 in that it has the power module 1 of this embodiment instead of the power module 1 of embodiment 1.

[0071] The power module 1 and the electronic device 2 of this embodiment have the following effects similar to those of the power module 1 and the electronic device 2 of the first embodiment.

[0072] In the power module 1 and electronic device 2 of this embodiment, the circuit pattern layer 12 includes a first circuit pattern partial layer 12a and a second circuit pattern partial layer 12b spaced apart from the first circuit pattern partial layer 12a. At least one power semiconductor element (e.g., power semiconductor element 14d) includes a first power semiconductor element (e.g., power semiconductor element 14d) bonded to the second circuit pattern partial layer 12b. The first portion of the electronic circuit board 3 is the first power semiconductor element. The second portion of the electronic circuit board 3 is the first circuit pattern partial layer 12a.

[0073] This prevents cracks from occurring in the insulating layer 11. It also prevents pump-out of the thermal interface material 32 caused by repeated thermal deformation of the insulating circuit board 10. This improves the reliability of the power module 1 and the electronic device 2 of this embodiment.

[0074] Fourth Embodiment A power module 1 and an electronic device 2 according to a fourth embodiment will be described with reference to Figures 11 and 12. The power module 1 and the electronic device 2 according to this embodiment have the same configurations and effects as the power module 1 and the electronic device 2 according to the first embodiment, but differ mainly in the following respects.

[0075] The bridge connection member 20 has a through hole 40 extending from the surface 20a to the surface 20b. The through hole 40 is formed, for example, by punching the bridge connection member 20. The bridge connection member 20 includes a side surface 20c and a side surface 20d opposite the side surface 20c. The side surfaces 20c and 20d are connected to the surface 20a and the surface 20b, respectively. The side surfaces 20c and 20d are connected to the ends 20i and 20j, respectively. The side surfaces 20c and 20d may extend along the direction in which the power semiconductor elements 14a and 14b are arranged. The side surfaces 20c and 20d may extend along the longitudinal direction of the external connection terminals 21.

[0076] The power module 1 and the electronic device 2 of this embodiment further include an insulating film 35 , a conductive pad 36 , a conductive wire 37 , and a signal terminal 38 .

[0077] The insulating film 35 is disposed on the surface 20b of the bridge connection member 20. Specifically, the insulating film 35 is disposed on a region of the surface 20b on the opposite side of the through-hole 40 from the external connection terminal 21. The insulating film 35 is formed of, for example, an inorganic insulating material such as silicon dioxide or silicon nitride, or an organic insulating material such as epoxy resin.

[0078] The conductive pad 36 is disposed on the insulating film 35. The conductive pad 36 is electrically insulated from the bridge connection member 20 by the insulating film 35. The conductive pad 36 is formed of a metal such as copper (Cu) or aluminum (Al).

[0079] The signal terminal 38 is made of a metal such as copper (Cu) and is conductive. The signal terminal 38 may be, for example, a terminal for applying a control signal to the power semiconductor element 14b to control the power semiconductor element 14b, or a terminal for detecting a current, such as a source current, flowing through the power semiconductor element 14b. The signal terminal 38 extends to the outside of the sealing member 30.

[0080] The signal terminals 38 are joined to the conductive pads 36 by a conductive joining member (not shown), such as solder or a sintered joining member (e.g., a metal fine particle sintered body such as a silver nanoparticle sintered body), or by welding, such as ultrasonic welding or laser welding. The signal terminals 38 are electrically insulated from the bridge connection member 20 by the insulating film 35. In a plan view of the main surface 11a of the insulating layer 11, the end of the signal terminal 38 proximal to the bridge connection member 20 (in this embodiment, the end of the signal terminal 38 joined to the conductive pad 36) is disposed inside the insulating circuit board 10.

[0081] The conductive wire 37 is connected to the power semiconductor element 14b and the conductive pad 36 through the through hole 40. The signal terminal 38 is electrically connected to the power semiconductor element 14b through the conductive pad 36 and the conductive wire 37. The conductive wire 37 is electrically insulated from the bridge connection member 20. The conductive wire 37 is a metal wire such as a copper (Cu) wire, a gold (Au) wire, or an aluminum (Al) wire.

[0082] 13 , in a first modification of the present embodiment, the bridge connection member 20 is provided with through-holes 41 extending from the surface 20a to the surface 20b instead of the through-holes 40. The through-holes 41 are provided on the side surfaces 20c and 20d. The through-holes 41 are formed, for example, by stamping the bridge connection member 20. The conductive wires 37 pass through the through-holes 41 and are connected to the power semiconductor elements 14b and the conductive pads 36. The signal terminals 38 are electrically connected to the power semiconductor elements 14b through the conductive pads 36 and the conductive wires 37.

[0083] 14 , in a second modification of the present embodiment, the conductive wire 37 straddles the side surfaces 20 c and 20 d and is connected to the power semiconductor element 14 b and the conductive pad 36. The signal terminal 38 is electrically connected to the power semiconductor element 14 b through the conductive pad 36 and the conductive wire 37.

[0084] The power module 1 and the electronic device 2 of this embodiment have the following advantages in addition to the advantages of the power module 1 and the electronic device 2 of the first embodiment.

[0085] The power module 1 and electronic device 2 of this embodiment further include a signal terminal 38 and a conductive wire 37. The signal terminal 38 and the conductive wire 37 are electrically insulated from the bridge connection member 20. The signal terminal 38 is electrically connected to at least one power semiconductor element (e.g., the power semiconductor element 14b) through the conductive wire 37. In a plan view of the main surface 11a of the insulating layer 11, the end of the signal terminal 38 that is closest to the bridge connection member 20 is disposed inside the insulating circuit board 10.

[0086] This reduces the area occupied by the insulating circuit board 10 and the signal terminals 38 in a plan view of the main surface 11a of the insulating layer 11. This allows the power module 1 to be made smaller.

[0087] In the power module 1 and electronic device 2 of this embodiment, the signal terminal 38 is electrically connected to at least one power semiconductor element (e.g., the power semiconductor element 14b) through a conductive wire 37 that passes through the bridge connection member 20.

[0088] This reduces the area occupied by the bridge connection members 20 and the signal terminals 38 in a plan view of the main surface 11a of the insulating layer 11. This allows the power module 1 to be made smaller.

[0089] Fifth Embodiment A power module 1 and an electronic device 2 according to a fifth embodiment will be described with reference to Figures 15 and 16. The power module 1 and the electronic device 2 according to this embodiment have the same configuration as the power module 1 and the electronic device 2 according to the fourth embodiment and achieve the same effects, but differ mainly in the following respects.

[0090] In place of the through-holes 40 of the fourth embodiment, through-holes 45 extending from the surface 20a to the surface 20b are provided in the bridge connection member 20. The through-holes 45 are formed by punching the bridge connection member 20, for example.

[0091] The power module 1 and electronic device 2 of this embodiment include an insulating film 46 and conductive pillars 47 instead of the insulating film 35, conductive pads 36, and conductive wires 37 of the fourth embodiment.

[0092] The insulating film 46 is disposed on the inner surface of the bridge connection member 20 that defines the through-hole 45. The insulating film 46 may be further disposed on the surface 20a and the surface 20b of the bridge connection member 20. The insulating film 46 is formed of, for example, an inorganic insulating material such as silicon dioxide or silicon nitride, or an organic insulating material such as epoxy resin.

[0093] The conductive pillar 47 is disposed in the through hole 45. The conductive pillar 47 extends in the thickness direction of the bridge connection member 20, where the surface 20a and the surface 20b are spaced apart from each other. The conductive pillar 47 penetrates the bridge connection member 20 and serves as a through electrode. The conductive pillar 47 is disposed on the insulating film 46. The conductive pillar 47 is electrically insulated from the bridge connection member 20 by the insulating film 46. The conductive pillar 47 is formed of a metal such as copper (Cu) or aluminum (Al). The conductive pillar 47 is electrically connected to the power semiconductor element 14b using a conductive bonding member 16e. The conductive bonding member 16e is, for example, solder or a sintered bonding member (e.g., a metal fine particle sintered body such as a silver nanoparticle sintered body).

[0094] The signal terminal 38 is joined to the conductive pillar 47 by a conductive joining member (not shown) such as solder or a sintered joining member (e.g., a metal fine particle sintered body such as a silver nanoparticle sintered body), or by welding such as ultrasonic welding or laser welding. The signal terminal 38 is electrically connected to the power semiconductor element 14b through the conductive pillar 47 and the conductive joining member 16e. The signal terminal 38 is electrically insulated from the bridge connection member 20 by the insulating film 46. In a plan view of the main surface 11a of the insulating layer 11, the end of the signal terminal 38 proximal to the bridge connection member 20 (in this embodiment, the end of the signal terminal 38 joined to the conductive pillar 47) is disposed inside the insulating circuit board 10.

[0095] 17 , in a first modification of the present embodiment, the bridge connection member 20 is provided with through-hole recesses 41 extending from the surface 20a to the surface 20b, instead of the through holes 45. The through-hole recesses 41 are provided on the side surfaces 20c and 20d. The through-hole recesses 41 are formed, for example, by stamping the bridge connection member 20. An insulating film 46 is disposed on the inner surface of the bridge connection member 20 that defines the through-hole recesses 41. A conductive pillar 47 is disposed within the through-hole recesses 41. The conductive pillar 47 is electrically insulated from the bridge connection member 20 by the insulating film 46. The signal terminal 38 is electrically connected to the power semiconductor element 14b through the conductive pillar 47 and the conductive bonding member 16e.

[0096] 18 , in a second modification of the present embodiment, the conductive pillars 47 are disposed on the side surfaces 20 c and 20 d of the bridge connection member 20 via an insulating film 46. The signal terminals 38 and the conductive pillars 47 are electrically insulated from the bridge connection member 20 by the insulating film 46. For example, the insulating film 46 is an insulating adhesive, and the conductive pillars 47 are bonded to the side surfaces 20 c and 20 d of the bridge connection member 20 using the insulating adhesive. The signal terminals 38 are electrically connected to the power semiconductor elements 14 b through the conductive pillars 47 and the conductive bonding members 16 e.

[0097] Referring to FIG. 19, the power module 1 and the electronic device 2 according to the third modification of the present embodiment further include an insulating film 35 and an electrical wiring 49 .

[0098] The insulating film 35 is disposed on the surface 20b of the bridge connection member 20. Specifically, the insulating film 35 is disposed on a region of the surface 20b on the opposite side of the through-hole 45 from the external connection terminal 21. The insulating film 35 is formed of, for example, an inorganic insulating material such as silicon dioxide or silicon nitride, or an organic insulating material such as epoxy resin. The insulating film 35 may be connected to the insulating film 46. The insulating films 35 and 46 may be a single insulating film.

[0099] The electrical wiring 49 is disposed on the insulating film 35. The electrical wiring 49 is electrically insulated from the bridge connection member 20 by the insulating film 35. The electrical wiring 49 is connected to the conductive pillars 47. The electrical wiring 49 is formed of a metal such as copper (Cu) or aluminum (Al).

[0100] The signal terminals 38 are joined to the electrical wiring 49 by a conductive joining member (not shown), such as solder or a sintered joining member (e.g., a metal fine particle sintered body such as a silver nanoparticle sintered body), or by welding, such as ultrasonic welding or laser welding. The signal terminals 38 are electrically connected to the conductive pillars 47 through the electrical wiring 49. The signal terminals 38 are electrically insulated from the bridge connection member 20 by the insulating films 35 and 46. In a plan view of the main surface 11a of the insulating layer 11, the end of the signal terminal 38 proximal to the bridge connection member 20 (in this embodiment, the end of the signal terminal 38 joined to the electrical wiring 49) is disposed inside the insulating circuit board 10.

[0101] The power module 1 and the electronic device 2 of this embodiment have the following effects similar to those of the power module 1 and the electronic device 2 of the fourth embodiment.

[0102] The power module 1 and electronic device 2 of this embodiment include a signal terminal 38 and a conductive pillar 47. The signal terminal 38 and the conductive pillar 47 are electrically insulated from the bridge connection member 20. The bridge connection member 20 includes a first surface (surface 20a) facing the electronic circuit board 3 and a second surface (surface 20b) opposite the first surface. The conductive pillar 47 extends in the thickness direction of the bridge connection member 20, with the first surface and the second surface spaced apart from each other. The signal terminal 38 is electrically connected to at least one power semiconductor element (e.g., power semiconductor element 14b) through the conductive pillar 47. In a plan view of the main surface 11a of the insulating layer 11, the end of the signal terminal 38 closest to the bridge connection member 20 is located inside the insulating circuit board 10.

[0103] This reduces the area occupied by the insulating circuit board 10 and the signal terminals 38 in a plan view of the main surface 11a of the insulating layer 11. This allows the power module 1 to be made smaller.

[0104] In the power module 1 and electronic device 2 of this embodiment, the signal terminal 38 is electrically connected to at least one power semiconductor element (e.g., the power semiconductor element 14b) through a conductive pillar 47 that penetrates the bridge connection member 20.

[0105] This reduces the area occupied by the bridge connection members 20 and the signal terminals 38 in a plan view of the main surface 11a of the insulating layer 11. This allows the power module 1 to be made smaller.

[0106] The power module 1 and the electronic device 2 of this embodiment further include an insulating film 35 and an electrical wiring 49. The insulating film 35 is disposed on the second surface (surface 20b) of the bridge connection member 20. The electrical wiring 49 is disposed on the insulating film 35. The signal terminal 38 is electrically connected to the conductive pillar 47 through the electrical wiring 49.

[0107] This increases the degree of freedom in arranging the conductive columns 47 and the signal terminals 38. This increases the degree of freedom in designing the power module 1 and the electronic device 2.

[0108] Sixth Embodiment A power module 1 and an electronic device 2 according to a sixth embodiment will be described with reference to Fig. 20. The power module 1 and the electronic device 2 according to this embodiment have the same configuration as the power module 1 and the electronic device 2 according to the fifth embodiment and achieve the same effects, but differ mainly in the following respects.

[0109] The power module 1 and electronic device 2 of this embodiment do not include the conductive pillars 47 (see FIGS. 15 and 16 ) of the fifth embodiment. The signal terminals 38 pass through the through holes 45. The signal terminals 38 are spaced apart from the bridge connection members 20 and are electrically insulated from the bridge connection members 20. The conductive bonding members 16e bond the signal terminals 38 to the power semiconductor elements 14b. The signal terminals 38 are electrically connected to the power semiconductor elements 14b using the conductive bonding members 16e. An insulating film 46 may be formed on the surface of the bridge connection members 20 that defines the through holes 45.

[0110] The power module 1 and the electronic device 2 of this embodiment have the following effects similar to those of the power module 1 and the electronic device 2 of the fifth embodiment.

[0111] The power module 1 and the electronic device 2 of this embodiment further include a signal terminal 38 and a conductive bonding member 16e. The signal terminal 38 is electrically insulated from the bridge connection member 20. The conductive bonding member 16e bonds the signal terminal 38 to at least one power semiconductor element (e.g., the power semiconductor element 14b). The signal terminal 38 penetrates the bridge connection member 20.

[0112] This reduces the area occupied by the bridge connection members 20 and the signal terminals 38 in a plan view of the main surface 11a of the insulating layer 11. This allows the power module 1 to be made smaller.

[0113] Seventh Embodiment In this embodiment, any one of the power modules 1 according to the first to sixth embodiments and their modifications is applied to a power conversion device. Although the present disclosure is not limited to a specific power conversion device, the seventh embodiment will be described below as a case where any one of the power modules 1 according to the first to sixth embodiments and their modifications is applied to a three-phase inverter.

[0114] The power conversion system shown in Fig. 21 is composed of a power supply 100, a power conversion device 200, and a load 300. The power supply 100 is a DC power supply and supplies DC power to the power conversion device 200. The power supply 100 is not particularly limited, and may be composed of, for example, a DC system, a solar cell, or a storage battery, or may be composed of a rectifier circuit or an AC / DC converter connected to an AC system. The power supply 100 may be composed of a DC / DC converter that converts DC power output from the DC system into a predetermined power.

[0115] The power conversion device 200 is a three-phase inverter connected between the power source 100 and the load 300, and converts DC power supplied from the power source 100 into AC power and supplies the AC power to the load 300. As shown in Fig. 21 , the power conversion device 200 includes a main conversion circuit 201 that converts DC power into AC power and outputs it, and a control circuit 203 that outputs a control signal to the main conversion circuit 201 to control the main conversion circuit 201.

[0116] The load 300 is a three-phase electric motor driven by AC power supplied from the power conversion device 200. The load 300 is not limited to a specific application, but is an electric motor mounted on various electrical devices, and is used as an electric motor for, for example, a hybrid vehicle, an electric vehicle, a railroad car, an elevator, or an air conditioning device.

[0117] The power conversion device 200 will be described in detail below. The main conversion circuit 201 includes switching elements (not shown) and freewheeling diodes (not shown). The switching elements switch the voltage supplied from the power supply 100, thereby converting DC power supplied from the power supply 100 into AC power and supplying it to the load 300. The main conversion circuit 201 may have a variety of specific circuit configurations. The main conversion circuit 201 of this embodiment is a two-level, three-phase full-bridge circuit, and may include six switching elements and six freewheeling diodes connected in anti-parallel to each switching element. The power semiconductor elements included in any of the power modules 1 of the first to sixth embodiments and their modifications may be used as each switching element and each freewheeling diode of the main conversion circuit 201. The power module 202 constituting the main conversion circuit 201 may be any of the power modules 1 of the first to sixth embodiments and their modifications. The six switching elements are connected in series with each other to form upper and lower arms, and each upper and lower arm constitutes one phase (U phase, V phase, and W phase) of the full-bridge circuit. The output terminals of the upper and lower arms, that is, the three output terminals of the main conversion circuit 201, are connected to a load 300.

[0118] The main conversion circuit 201 also includes a drive circuit (not shown) that drives each switching element. The drive circuit may be built into the power module 202 or provided externally to the power module 202. The drive circuit generates drive signals that drive the switching elements included in the main conversion circuit 201 and supplies the drive signals to the control electrodes of the switching elements of the main conversion circuit 201. Specifically, in accordance with a control signal from the control circuit 203, the drive circuit outputs a drive signal that turns the switching element on and a drive signal that turns the switching element off to the control electrodes of each switching element.

[0119] The control circuit 203 controls the switching elements of the main conversion circuit 201 so that power is supplied to the load 300. Specifically, it calculates the time (on time) that each switching element of the main conversion circuit 201 should be in the on state based on the power to be supplied to the load 300. For example, the main conversion circuit 201 can be controlled by PWM control, which modulates the on time of the switching elements according to the voltage to be output to the load 300. The control circuit 203 then outputs a control command (control signal) to a drive circuit included in the main conversion circuit 201 so that an on signal is output to a switching element that should be in the on state at each time point, and an off signal is output to a switching element that should be in the off state at each time point. In accordance with this control signal, the drive circuit outputs an on signal or an off signal as a drive signal to the control electrode of each switching element.

[0120] In the power conversion device 200 of this embodiment, any of the power modules 1 of the first to sixth embodiments and their modifications is applied as the power module 202 included in the main conversion circuit 201. Therefore, the power conversion device 200 of this embodiment has improved reliability.

[0121] In the present embodiment, an example in which the present disclosure is applied to a two-level three-phase inverter has been described, but the present disclosure is not limited to this and can be applied to various power conversion devices. Although the present embodiment describes a two-level power conversion device, the present disclosure may be applied to a three-level power conversion device or a multi-level power conversion device. When the power conversion device supplies power to a single-phase load, the present disclosure may be applied to a single-phase inverter. When the power conversion device supplies power to a DC load or the like, the present disclosure may be applied to a DC / DC converter or an AC / DC converter.

[0122] The power conversion device to which the present disclosure is applied is not limited to cases where the load is an electric motor, and may be incorporated, for example, into a power supply device for an electric discharge machine or a laser processing machine, or a power supply device for an induction heating cooker or a contactless power supply system. The power conversion device to which the present disclosure is applied may also be used as a power conditioner for a solar power generation system, a power storage system, or the like.

[0123] The presently disclosed embodiments 1 to 7 and their modifications should be considered to be illustrative in all respects and not restrictive. Unless there is a contradiction, at least two of the presently disclosed embodiments 1 to 7 and their modifications may be combined. The scope of the present disclosure is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0124] REFERENCE SIGNS LIST 1, 1a, 202 Power module, 2, 2a Electronic device, 3 Electronic circuit board, 10 Insulated circuit board, 11 Insulating layer, 11a, 11b Main surface, 12 Circuit pattern layer, 12a First circuit pattern partial layer, 12b Second circuit pattern partial layer, 13 Conductive pattern layer, 14a, 14b, 14c, 14d Power semiconductor element, 15a, 15b, 15c, 15d, 16a, 16b, 16c, 16d, 16e Conductive bonding member, 17 Positive electrode terminal, 18 Negative electrode terminal, 19 Output terminal, 20 Bridge connection member, 20a, 20b Surface, 20c, 20d Side, 20i, 20j End, 21, 26, 29 External connection terminal, 25 Bridge connection member, 25a, 25b Surface, 25i, 25j End, 30 Sealing member, 32 thermal interface material, 32a void, 33 cooler, 35, 46 insulating film, 36 conductive pad, 37 conductive wire, 38 signal terminal, 40, 45 through hole, 41 through recess, 47 conductive column, 49 electrical wiring, 100 power supply, 200 power conversion device, 201 main conversion circuit, 203 control circuit, 300 load.

Claims

1. A power module comprising: an insulating circuit board; an electronic circuit board including at least one power semiconductor element mounted on the insulating circuit board; a conductive bridge connection member; and an external connection terminal connected to the bridge connection member, wherein the insulating circuit board includes an insulating layer having a main surface and a circuit pattern layer disposed on the main surface, the bridge connection member is connected to a first portion of the electronic circuit board and a second portion of the electronic circuit board, and the linear expansion coefficient of the bridge connection member is between the linear expansion coefficient of the insulating circuit board and the linear expansion coefficient of the external connection terminal.

2. The power module according to claim 1, wherein the at least one power semiconductor element includes a first power semiconductor element bonded to the circuit pattern layer and a second power semiconductor element bonded to the circuit pattern layer, the first portion being the first power semiconductor element, and the second portion being the second power semiconductor element.

3. The power module according to claim 1, wherein the at least one power semiconductor element includes a first power semiconductor element bonded to the circuit pattern layer, the first portion being the first power semiconductor element, and the second portion being the circuit pattern layer.

4. The power module described in claim 1, wherein the circuit pattern layer includes a first circuit pattern portion layer and a second circuit pattern portion layer spaced apart from the first circuit pattern portion layer, the at least one power semiconductor element includes a first power semiconductor element bonded to the second circuit pattern portion layer, the first portion is the first power semiconductor element, and the second portion is the first circuit pattern portion layer.

5. A power module as claimed in any one of claims 1 to 4, further comprising: a signal terminal electrically insulated from the bridge connection member; and a conductive wire electrically insulated from the bridge connection member, the signal terminal being electrically connected to the at least one power semiconductor element through the conductive wire, and an end of the signal terminal proximate to the bridge connection member in a plan view of the main surface is disposed inside the insulating circuit board.

6. The power module according to claim 5, wherein said signal terminal is electrically connected to said at least one power semiconductor element through said conductive wire passing through said bridge connection member.

7. A power module according to any one of claims 1 to 4, comprising: a signal terminal electrically insulated from the bridge connection member; and a conductive pillar electrically insulated from the bridge connection member, the bridge connection member including a first surface facing the electronic circuit board and a second surface opposite the first surface, the conductive pillar extending in a thickness direction of the bridge connection member where the first surface and the second surface are spaced apart from each other, the signal terminal being electrically connected to the at least one power semiconductor element through the conductive pillar, and an end of the signal terminal proximate to the bridge connection member in a plan view of the main surface is located inside the isolated circuit board.

8. The power module according to claim 7, wherein the signal terminal is electrically connected to the at least one power semiconductor element through the conductive pillar penetrating the bridge connection member.

9. The power module according to claim 8, further comprising: an insulating film disposed on the second surface; and electrical wiring disposed on the insulating film, wherein the signal terminal is electrically connected to the conductive pillar through the electrical wiring.

10. A power module as claimed in any one of claims 1 to 4, further comprising: a signal terminal electrically insulated from said bridge connection member; and a conductive joining member joining said signal terminal to said at least one power semiconductor element, said signal terminal passing through said bridge connection member.

11. A power module as described in any one of claims 1 to 4, wherein the bridge connection member includes a first end and a second end opposite the first end, and in a plan view of the main surface, the first end of the bridge connection member overlaps the first portion, and the second end of the bridge connection member overlaps the second portion.

12. A power module according to any one of claims 1 to 11, wherein the bridge connection member is formed of a copper-Invar-copper clad material, an iron-nickel alloy, a copper-molybdenum composite material, a copper-molybdenum clad material, a copper-tungsten composite material, an aluminum-silicon carbide composite material, or a printed circuit board.

13. An electronic device comprising: a cooler; a thermal interface material; and the power module according to any one of claims 1 to 12 attached to the cooler via the thermal interface material.

14. A power conversion device comprising: a main conversion circuit having the power module according to any one of claims 1 to 12, which converts and outputs input power; and a control circuit which outputs a control signal for controlling the main conversion circuit to the main conversion circuit.

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