JP2014187149A - Power module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve workability by preventing reduced radiation due to the generation of an area having insufficient pressing force between a power semiconductor unit and a heat radiation unit.SOLUTION: A part of each radiation unit 35, 36 protrudes outer than one side edge k of each conductor plate 33, 34, to form a protrusion 71 in the region of the part. A gate electrode of a semiconductor element 31 and each lead terminal 24U, 24L are bonded by a wire 2. The region of the conductor plate 35, 36 protruding outer than the one side edge k of the conductor plate 33, 34 is covered with a sealing resin 6. A distance X between the top face 71a of the protrusion 71 and an insulation layer 51 is smaller than a thickness T of the conductor plate 33, 34.

Description

  The present invention relates to a power module, and more particularly, to a power module including a heat radiating portion that radiates heat generated from a power semiconductor element.

There is known a power module having a structure in which a power semiconductor module having a power semiconductor element is housed in a metal case provided with a heat radiating portion on both front and back surfaces. The power module is used as a power conversion device mounted on an electric vehicle such as an electric vehicle or a hybrid vehicle.
The power semiconductor module includes a power semiconductor element, the first electrode provided on one surface of the power semiconductor element is connected to the first conductor plate, and the second electrode provided on the other surface of the power semiconductor element is It has a structure connected to the second conductor plate. A part of the second conductor plate extends outward from one side edge of the first conductor plate, and the extended region is covered with a sealing resin.

The first and second conductor plates are made of metal, and the second conductor plate functions as a lead terminal connected to the second electrode of the power semiconductor element. The first conductor plate is connected to the first electrode of the power semiconductor element via a lead terminal by a bonding wire. A part of the lead terminal is covered with a sealing resin.
The power module is formed by housing the power semiconductor module in a metal case and pressurizing the heat dissipating parts on both the front and back surfaces to the power semiconductor module side. By pressurizing the heat dissipating part, heat conduction between the first conductor plate and the second conductor plate and each heat dissipating part is improved, and heat dissipating property is improved (for example, see Patent Document 1).

JP 2012-5322 A

In the power module described in the above cited reference 1, the first conductor plate is not extended on the opposite surface side of the region on the one side portion of the second conductor plate, and between the heat radiating portion on the opposite side. Is provided only with a sealing resin. The sealing resin has a smaller elastic modulus than the metal that is the material of the first conductor plate.
For this reason, in the operation of pressurizing the heat radiating portion and pressing it against the first and second conductor plates, the region of the second conductor plate that extends outward from one side edge of the first conductor plate has a pressing force. Becomes an area where it is difficult to transmit. If a region where the pressing force between the heat radiating portion and the second conductor plate is insufficient is generated, the entire heat radiating characteristic is lowered. Therefore, it takes a long time to avoid this, and the workability is poor.

  The power module of the present invention includes a power semiconductor element having a first electrode on one side and a second electrode on the other side, a first conductor plate bonded to one side of the power semiconductor element, and the other side of the power semiconductor element. A second conductive plate joined to the power semiconductor element, a power semiconductor element, a first conductive plate, an insertion port for inserting the second conductive plate, a first heat radiating portion capable of conducting heat to the first conductive plate, A second heat radiating portion capable of conducting heat to the second conductor plate, and a metal case housing the power semiconductor element, the first conductor plate, and the second conductor plate, and housed in the metal case. , A power semiconductor element, a first conductor plate, and a sealing resin surrounding an outer periphery of the second conductor plate, and a part of the second conductor plate is outward from one side edge of the first conductor plate. The sealing resin has a portion that covers the extended region of the second conductive plate, and the second conductive plate extends in the sealing resin. A portion covering the area that is, protrusions protruding in the first heat radiating plate side is disposed.

  According to the present invention, the pressing force is transmitted to the region of the second conductor plate extending outward from one side edge of the first conductor plate only through the protrusion or the protrusion and the sealing resin. The Accordingly, the pressing force is improved as compared with the case where the pressure is transmitted only through the sealing resin, and accordingly, workability can be improved.

The external appearance perspective view of one embodiment of the power module of the present invention. II-II sectional view taken on the line of FIG. The external appearance perspective view of the surface side of a power semiconductor module. The external appearance perspective view of the back surface side of a power semiconductor module. The perspective view of the state which removed the sealing resin in FIG. (A) is the VIa-VIa sectional view taken on the line in FIG. 5, (b) is VIb-VIb sectional view taken on the line in FIG. FIG. 6 is a circuit diagram as one embodiment built in the power semiconductor module illustrated in FIG. 5. Sectional drawing for demonstrating one Embodiment of the manufacturing method of the power module of this invention. Sectional drawing for demonstrating the next process of FIG. Sectional drawing for demonstrating the next process of FIG. FIG. 3 is an enlarged view of a region XI illustrated in FIG. 2. The characteristic view which shows the relationship between the thickness T of a conductor board / distance X of a processus | protrusion, and an insulating layer, and the increase rate of the pressure transmitted to a conductor board. The external appearance perspective view of the power semiconductor module as Embodiment 2 of this invention. The XIV-XIV sectional view taken on the line in FIG. Sectional drawing of the power module as Embodiment 3 of this invention. Sectional drawing of the power module as Embodiment 4 of this invention.

Hereinafter, an embodiment of a power module according to the present invention will be described with reference to the drawings.
--Embodiment 1--
[Outline of power module]
A hybrid vehicle or an electric vehicle is equipped with a power conversion device that drives a motor. The power conversion device converts the DC power supplied from the battery into AC power to drive the motor, and conversely converts the AC power regenerated by the motor into DC power and stores it in the power storage device.
The power converter includes a power module having a power semiconductor element, and drives the motor by controlling the on / off operation of the semiconductor element at a high voltage to obtain a high output.
Along with the on / off operation, the amount of heat generated from the semiconductor element is large. Therefore, the power module is required to have a structure with high heat dissipation performance.

[Overall structure of power module]
FIGS. 1-12 is a figure which concerns on Embodiment 1 of the power module of this invention.
FIG. 1 is an external perspective view of a power module as an embodiment according to the present invention, and FIG. 2 is a sectional view taken along line II-II in FIG.
The power module 100 includes a power semiconductor module 30 (see FIGS. 3 and 4) that includes a switching element and is transfer-molded in a metal case 40 that is a CAN cooler. The power module 100 is used in, for example, a power conversion device mounted on an electric vehicle such as an electric vehicle or a hybrid vehicle.
Here, the CAN type cooler is a cylindrical cooler having an insertion port 17 on one surface and a bottom on the other surface. The metal case 40 is formed of a member having electrical conductivity, for example, a composite material such as Cu, Cu alloy, Cu—C, or Cu—CuO, or a composite material such as Al, Al alloy, AlSiC, or Al—C. ing.

  The metal case 40 is formed by integral molding into a bottomed thin can shape having no opening other than the insertion port 17 provided on one side, and the flange 11 is provided around the insertion port 17. It has been. A heat radiating portion 41a is provided on one of the two opposing surfaces having a large area of the flat case, and a heat radiating portion 41b (see FIG. 2) is provided on the other surface. The heat dissipating part 41a and the heat dissipating part 41b function as heat dissipating walls of the metal case 40, and a plurality of heat dissipating fins 42 are arranged in a matrix on the outer side surfaces thereof.

The surrounding area surrounding the heat radiating portion 41a and the heat radiating portion 41b is a curved portion 44 that is thin and easily plastically deformable. By thinning the curved portion 44, when the heat radiating portion 41a and the heat radiating portion 41b are pressed in the case inner direction in the manufacturing process of the power module 100, they can be easily deformed. In addition, the shape of the metal case 40 does not need to be an accurate rectangular parallelepiped, and the corners may be formed in a curved surface.
Further, a plurality of heat radiation fins 42 are molded integrally with the heat radiation part 41a or the heat radiation part 41b by forging or the like, and the case main body having openings corresponding to the heat radiation parts 41a and 41b is highly waterproof such as welding. The metal case 40 may be formed by integration by a joining method.

The power semiconductor module 30 is accommodated in the metal case 40. The power semiconductor module 30 includes power semiconductor elements 31U and 31L, diodes 32U and 32L, conductor plates 33 to 36, and a first sealing resin 6. The outer periphery of the power semiconductor module 30 is filled with the second sealing resin 12 so as to surround the first sealing resin 6. A heat conductive insulating layer 51 is interposed between the power semiconductor module 30 and the heat radiating portions 41a and 41b.
As will be described in detail later, the gate electrode 81 (see FIG. 5) of the power semiconductor element 31 is connected to the lead terminals (electrode terminals) 24U and 24L by the wire 2. The conductor plates 33 to 36 are made of metal, and a DC positive terminal 35a and an AC output terminal 36a are integrated with the conductor plates 35 and 36, respectively. Each of the conductor plates 35 and 36 (second conductor plate) has an area larger than that of the conductor plates 33 and 34 (first conductor plate), and a part thereof is one side edge k of the conductor plates 33 and 34. More outward, that is, outward toward the insertion port 17 side. A protrusion 71 is formed in an extended region of the conductor plates 35 and 36 where the conductor plates 33 and 34 do not face each other, and this region is covered with the first sealing resin 6 together with the wire 2.
Details of the power semiconductor module 30 will be described below.

[Power semiconductor module]
3 is an external perspective view of the front surface side of the power semiconductor module, FIG. 4 is an external perspective view of the back surface side of the power semiconductor module, and FIG. 5 is a perspective view in a state where the sealing resin in FIG. 4 is removed. FIG.
On the surface side of the power semiconductor module 30, a DC positive-side conductor plate 35 and an AC output-side conductor plate 36 are arranged on the same plane. As shown in FIG. 3, the first sealing resin 6 of the power semiconductor module 30 exposes the upper surface 35 b of the conductor plate 35 and the upper surface 36 b of the conductor plate 36 on the surface side of the power semiconductor module 30. The entire circumference of the plates 35 and 36 is covered. The surface of the first sealing resin 6 is flush with the upper surface 35 b of the conductor plate 35 and the upper surface 36 b of the conductor plate 36.

  Similarly, on the back surface side of the power semiconductor module 30, an AC output side conductor plate 33 (first conductor plate) and a DC negative electrode side conductor plate (first conductor plate) 34 are arranged on the same plane. ing. As illustrated in FIG. 4, the first sealing resin 6 exposes the upper surface 33 b of the conductor plate 33 and the upper surface 34 b of the conductor plate 34 on the back surface side of the power semiconductor module 30. The entire circumference of the is covered. The surface of the first sealing resin 6 is flush with the upper surface 33 b of the conductor plate 33 and the upper surface 34 b of the conductor plate 34. The conductor plates 33 to 36 are made of, for example, aluminum.

  Power semiconductor elements 31U and 31L have one surface joined to conductor plates 35 and 36 via solder 61, and the other surface joined to conductor plates 33 and 34 via solder 61 (see FIG. 2). Although not shown, the diodes 32 </ b> U and 32 </ b> L are similarly joined on one side to the conductor plates 35 and 36 via the solder 61 and on the other side to the conductor plates 33 and 34 via the solder 61.

FIG. 7 is a circuit diagram showing an embodiment of a circuit built in the power semiconductor module 30. In the following description, this circuit diagram is also referred to.
The power semiconductor element 31U, the diode 32U, the power semiconductor element 31L, and the diode 32L constitute the upper and lower arm series circuit 121.
A DC positive electrode terminal 35 a is integrally formed on the DC positive electrode side conductor plate 35, and an AC output terminal 36 a is integrally formed on the AC output side conductor plate 36. Further, a power semiconductor element 31U and a diode 32U are joined to the conductor plate 35 on the DC positive electrode side, and an upper arm circuit is constituted by these elements, and the input / output portion of the power semiconductor element 31U has a plurality of signal terminals 24U. (Lead terminal) and wire 2 (see FIG. 5).
A power semiconductor element 31L and a diode 32L are joined to the conductor plate 36 on the AC output side to form a lower arm circuit. The input / output portion of the power semiconductor element 31L has a plurality of signal terminals 24L (lead terminals). Are connected by a wire 2.

As shown in FIGS. 5 and 6, the conductor plate 35, the conductor plate 33, the DC positive terminal 35a, the signal terminal 24U, the power semiconductor element 31U, and the diode 32U constitute a power semiconductor unit 10A. The conductor plate 36, the conductor plate 34, the AC output terminal 36a, the signal terminal 24L, the power semiconductor element 31L, and the diode 32L constitute the power semiconductor unit 10B.
As shown in FIG. 5, the conductive plate 33 has a protruding portion 33 c that protrudes toward the conductive plate 34 on the lower end side, and the conductive plate 34 protrudes toward the conductive plate 33 on the upper side. Have

6A is a cross-sectional view taken along line VIa-VIa in FIG. 5, and FIG. 6B is a cross-sectional view taken along line VIb-VIb in FIG.
As shown in FIG. 6A, a connecting member 38 is disposed between the protruding portion 33 c of the conductor plate 33 and the conductor plate 36, and both surfaces of the connecting member 38 are respectively extended by solder 62. The portion 33c and the conductor plate 36 are joined. Further, as illustrated in FIG. 6B, the overhanging portion 34 c of the conductor plate 34 and the conductor plate 36 are electrically connected by solder 63. As a result, as shown in FIG. 7, a circuit in which the conductor plate 33 and the conductor plate 36 are connected and the conductor plate 36 is connected to the conductor plate 34 is configured.

The power semiconductor elements 31U and 31L and the diodes 32U and 32L have a plate-like flat structure, and electrodes that occupy almost the entire surface are formed on one surface and the other surface.
A collector electrode (not shown) is formed on one surface of the power semiconductor elements 31U and 31L, and the collector electrode is joined to the conductor plate 35 or 36 by the solder 61 as described above. As shown in FIG. 5, a plurality of gate electrodes 81 and one emitter electrode 82 are formed on the other surface of the power semiconductor elements 31U and 31L. The emitter electrode 82 occupies a large area that is almost nearly the entire surface, and the emitter electrode 82 is joined to the conductor plate 33 or 34 by the solder 61 as described above. Usually, a plurality of power semiconductor elements 31U and 31L are arranged in parallel between the conductor plates 35 and 33 or between the conductor plates 36 and 34, and function as one power semiconductor element. Although the emitter electrode 82 is illustrated as one electrode having a large area, it may be separated into a plurality of electrodes. The gate electrode 81 of the power semiconductor element 31U and the signal terminal 24U are connected by the wire 2 using a wire bonding method. Similarly, the gate electrode 81 of the power semiconductor element 31L and the signal terminal 24L are connected by the wire 2 using a wire bonding method.

Although not shown, a cathode electrode is formed over one surface of the diodes 32U and 32L, and an anode electrode is formed over the entire other surface. As described above, the cathode electrodes of the diodes 32U and 32L are joined to the conductor plate 35 or 36, and the anode electrode is joined to the conductor plate 33 or 34 by the solder 61.
The collector electrodes of the power semiconductor elements 31U and 31L, the emitter electrode 82, the gate electrode 81, and the cathode electrodes and anode electrodes of the diodes 32U and 32L are formed of, for example, copper, aluminum, nickel, etc., and tin, gold, It is plated with silver or nickel.

  On the conductor plate 35, protrusions 71 are formed on both sides of the wire 2 connecting the gate electrode 81 of the power semiconductor element 31U and the signal terminal 24U. Similarly, protrusions 71 are formed on both sides of the conductor plate 36 across the wire 2 connecting the gate electrode 81 of the power semiconductor element 31L and the signal terminal 24L. Each protrusion 71 is integrally formed with the conductor plate 35 or the conductor plate 36 by a forging method or the like.

The power semiconductor module 30 has a structure in which the projections 71 and the wires 2 of the power semiconductor units 10 </ b> A and 10 </ b> B are covered and sealed with the first sealing resin 6.
Next, a method for manufacturing the power module 100 will be described.

[Power Module Manufacturing Method]
8-10 is a figure for demonstrating the manufacturing method of the power module 100. FIG.
First, as illustrated in FIG. 8, the power semiconductor module 30 is manufactured.
The collector electrodes of the power semiconductor elements 31U and 31L and the anode electrodes of the diodes 32U and 32L are joined to the conductor plate 35 or 36 by solder 61. Further, the emitter electrode 82 of the power semiconductor elements 31U and 31L and the cathode electrode of the diodes 32U and 32L are joined to the conductor plate 33 or 34 by the solder 61.

  The plurality of signal terminals 24U are each wire-bonded to the gate electrode 81 of the power semiconductor element 31U, and similarly, the plurality of signal terminals 24L are respectively wire-bonded to the gate electrode 81 of the power semiconductor element 31L. Then, the outer periphery of the power semiconductor elements 31U and 31L, the diodes 32U and 32L, and the conductor plates 33 to 36 is sealed with the first sealing resin 6 by the first sealing resin 6 using a transfer molding method or the like. The first sealing resin 6 is formed so as to cover all the wires 2 and the protrusions 71. Thereby, the power semiconductor module 30 is formed.

  Insulating layers 51 are formed on the front and back surfaces of the power semiconductor module 30. The insulating layer 51 can be formed by a method of attaching a heat conductive insulating sheet, a method of forming an insulating layer by printing, coating, or the like.

  As shown in FIG. 9, the power semiconductor module 30 in which the insulating layers 51 are formed on both the front and back surfaces is inserted from the insertion port 17 of the metal case 40 and stored in the metal case 40.

  Then, as shown in FIG. 10, a flat pressing jig is pressed against the upper surface of the heat radiation fin 42 of the heat radiation portion 41a and the upper surface of the heat radiation fin 42 of the heat radiation portion 41b, and the power semiconductor module Pressurize toward 30 side. As a result, the metal case 40 is bent with the connecting portion side of the bending portion 44 to the heat dissipation portions 41a and 41b facing the power semiconductor module 30 side, and the conductor plates 35 and 36 of the power semiconductor module 30 are changed to the heat dissipation portion 41a. In addition, the conductor plates 33 and 34 are press-contacted or bonded to the heat radiating portion 41 b via the insulating layer 51. After that, when the second sealing resin 12 is filled in the metal case 40 and cured, the power module 100 illustrated in FIGS. 1 and 2 is formed.

FIG. 11 is an enlarged view of the region XI shown in FIG.
The protrusion 71 formed on the conductor plate 35 or 36 protrudes into the first sealing resin 6 toward the opposing heat radiating portion 41b. The upper surface 71a of the protrusion 71 and the insulating layer 51 are separated by a distance (gap) X, and the first sealing resin 6 is interposed in this gap. For this reason, the pressing force from the opposite heat radiating part 41b side is transmitted to the conductor plates 35 and 36 via the first sealing resin 6 and the protrusions 71 filled in the gap. The elastic modulus is smaller for the resin than for the metal, but since a part of the transmission path by the resin is made of metal, the pressing force transmitted to the conductor plates 35 and 36 is increased. Thereby, compared with the case where there is no protrusion as in the conventional example, the adhesiveness with the heat radiating portion 41a is improved on the entire surface of the conductor plates 35 and 36, and the heat radiating performance is improved.

[Verification of projection effect]
The relationship between the distance X between the upper surface 71a of the protrusion 71 and the inner surface 51a of the insulating layer 51 and the thickness T of the conductor plates 33 and 34 was examined.
FIG. 12 shows the relationship between (thickness T of the conductor plates 33 and 34) / (distance X between the upper surface 71a of the protrusion 71 and the insulating layer 51) and the increasing rate of the pressing force transmitted to the conductor plates 35 and 36. FIG.
As shown in FIG. 12, in a region where T / X is approximately 3 or less, the pressing force transmitted to the conductor plates 35 and 36 increases substantially in proportion to T / X. However, when T / X exceeds 3, the increase in the pressing force transmitted to the conductor plates 33 and 34 is saturated.

That is, the distance X between the upper surface 71a of the protrusion 71 and the insulating layer 51 is preferably as small as possible. However, if the distance X is about 1/3 or less of the thickness T of the conductor plates 33 and 34, the pressing force is reduced even if the distance X is further reduced. It can be seen that almost no increase is expected.
In FIG. 12, the increase in the pressing force is only 20% at the maximum as compared with the case where the protrusion 71 is not formed. However, a further increase in the pressing force can be expected by increasing the area of the upper surface 71a of the protrusion 71.

As described above, according to the above-described embodiment, a part of the second conductor plates 35 and 36 is located outside the one side edge k of the first conductor plates 33 and 34, that is, the conductor plates 33 and 34. The second conductor plates 35, 36 extending outward are provided with protrusions 71 so as not to oppose each other, and this region is covered with the first sealing resin 6. Although the resin has a smaller elastic modulus than that of the metal, the pressing force transmitted to the second conductor plates 35 and 36 can be increased by forming the protrusions 71.
Therefore, the adhesiveness between the heat radiating portion 41a and the second conductor plates 35 and 36 can be made uniform over the entire area of the second conductor plates 35 and 36. The performance can be improved.

  In the above embodiment, since the protrusions 71 are provided on both sides of the wire 2 connecting the gate electrode 81 of the power semiconductor element 31U and the signal terminal 24U, the bonding work by the wire 2 is not hindered. Absent.

  In the above embodiment, since the protrusion 71 is integrally formed with the conductor plates 35 and 36, the number of parts does not increase, and the assembling work does not increase except for the process of integrally forming the protrusion 71.

  In the above embodiment, (thickness T of the conductor plates 33 and 34) / (distance X between the upper surface 71a of the protrusion 71 and the insulating layer 51) and the increasing rate of the pressing force transmitted to the conductor plates 35 and 36. The relationship was verified. For this reason, it became possible to immediately determine the height of the protrusion 71 in response to an increase in the required pressing force.

--Embodiment 2--
13 is an external perspective view of a power semiconductor module as Embodiment 2 of the present invention, and FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG.
The power module 100A of the second embodiment is different from the power module 100 of the first embodiment in that the protrusion 71A is formed as a separate member from the conductor plates 35 and 36.
As shown in FIG. 14, the protrusion 71 </ b> A formed as a separate member is joined to the conductor plates 35 and 36 by solder 64. The protrusion 71A may be formed of the same material as the conductor plates 35 and 36, or may be formed of a different material. The protrusion 71A and the conductor plates 35 and 36 are preferably formed of a material having a close elastic modulus.
Other structures in the second embodiment are the same as those in the first embodiment, and the corresponding members are denoted by the same reference numerals and description thereof is omitted.

Also in the second embodiment, the projection 71A is provided in the region of the second conductor plates 35 and 36 extending outward from the one side edge k of the first conductor plates 33 and 34, and this region is sealed in the first seal. Since it is covered with the stop resin 6, the pressing force transmitted to the second conductor plates 35 and 36 can be increased as in the first embodiment.
In addition, since the projection 71A is formed by a member separate from the conductor plates 35 and 36, the number of assembly steps is increased, but a molding apparatus such as a forging device for integrally molding the projection 71A with the conductor plates 35 and 36 can be provided. The cost to introduce can be reduced.

--Embodiment 3--
FIG. 15 is a cross-sectional view of a power module as Embodiment 3 of the present invention.
The power module 100B shown in the third embodiment is different from the power module 100 of the first embodiment in that the protrusion 71B is formed so as to reach the opposing insulating layer 51.
In the power module 100B shown in the third embodiment, the distance X = 0 between the protrusion 71B and the insulating layer 51 pressed against the heat radiating portion 41b, in other words, there is no gap. Other structures in the third embodiment are the same as those in the first embodiment, and the corresponding members are denoted by the same reference numerals and description thereof is omitted.

As described above, when the distance X is less than about 1/3 of the thickness T of the conductor plates 33 and 34, the pressing force transmitted to the heat radiating portions 35 and 36 is saturated. However, since the metal protrusion 71B is directly connected to the insulating layer 51, the heat transfer efficiency between the first conductor plates 33 and 34 and the second heat radiating portions 35 and 36 is improved, and the power module 100B. Uniform the overall heat dissipation characteristics and improve its efficiency.
Also in the third embodiment, the protrusion 71B is provided in the region of the second conductor plates 35 and 36 extending outward from the one side edge k of the first conductor plates 33 and 34, and this region is sealed in the first seal. Since it is covered with the stop resin 6, the pressing force transmitted to the second conductor plates 35 and 36 can be increased as in the first and second embodiments.

--Embodiment 4--
FIG. 15 is a cross-sectional view of a power module as Embodiment 4 of the present invention.
The power module 100C shown in the fourth embodiment is different from the power module 100 of the first embodiment in the following two points.
(1) The DC positive terminal of the conductor plate 35A is formed as a positive lead 35c, and the AC output terminal of the conductor plate 36A is formed as a separate member from the conductor plates 35A and 36A. It is joined to the plates 35A and 36A.
(2) Each of the positive electrode lead 35c and the output lead 36c is formed with a protrusion 71C at the tip portion on the side joined to the conductor plates 35A and 36A. Further, the end opposite to the protrusion 71C extends to the outside of the first sealing resin 6 and serves as a terminal to which wiring is connected.

Other structures in the fourth embodiment are the same as those in the first embodiment, and the corresponding members are denoted by the same reference numerals and description thereof is omitted.
In the power module 100C shown in the fourth embodiment, the shapes of the conductor plates 35A and 36A are simplified, the productivity of the molding process is improved, and the number of fractions from the base material is increased.
Also in the fourth embodiment, the projections 71C of the positive lead 35c and the output lead 36c are formed in the regions of the second conductive plates 35A and 36A extending outward from the one side edge k of the first conductive plates 33 and 34, respectively. Since this region is covered with the first sealing resin 6, the pressing force transmitted to the second conductor plates 35 and 36 can be increased as in the first embodiment.
In the fourth embodiment, since the positive electrode lead 35c and the output lead 36c are interposed between the conductor plates 35A and 36A and the insulating layer 51 facing each other, the thickness of the first sealing resin 6 is accordingly increased. Get smaller. Therefore, even when the protrusion 71C is not provided on the positive lead 35c and the output lead 36c, the transmission efficiency of the pressing force is improved. For this reason, the positive electrode lead 35c and the output lead 36c not provided with the protrusion 71C are also included in the protrusion of the present invention.

[Application to power conversion equipment]
The power modules 100 and 100A to 100C described above are used as, for example, power conversion devices mounted on hybrid vehicles and electric vehicles, power conversion devices such as trains, ships, and airplanes, and control devices for motors that drive factory equipment. The present invention can be applied to an industrial power converter that is used, or a household power converter that is used in a control device for an electric motor that drives a household solar power generation system or household electrical appliance.

In the above embodiment, the metal case 40 is illustrated as having a structure in which a plurality of power semiconductor units 10A and 10B are accommodated. However, only one of the power semiconductor units 10A and 10B is accommodated in the metal case 40. It can also be applied to cases.
Moreover, although the circuit comprised by the power semiconductor module 30 was illustrated as the upper-lower arm series circuit 121, it is applicable also to the power semiconductor module 30 which comprises another circuit.

  In the said embodiment, the side surface of power semiconductor element 31U, 31L and diode 32U, 32L was covered with the 1st sealing resin 6, and it illustrated as a structure which covers the outer periphery of the 1st sealing resin 6 with the 2nd sealing resin 12. However, the side surfaces of the power semiconductor elements 31U and 31L and the diodes 32U and 32L may be covered with one sealing resin.

  In the said embodiment, it illustrated as a structure in which the heat conductive insulating layer 51 is interposed between the metal case 40 and the both side surfaces of the power semiconductor module 30. However, the metal case 40 and both side surfaces of the power semiconductor module 30 may be in direct contact with each other, or may be crimped with another heat conducting member interposed therebetween. It is only necessary that the both side surfaces of the two are coupled so as to be able to conduct heat.

  The shape and arrangement of the protrusions 71 and 71A to 71C shown in the above embodiments are merely examples, and the protrusions 71 and 71A to 71C may have other shapes such as a columnar shape or arranged in a plurality of rows. However, it is possible to change only one, not a plurality, or appropriately.

  In each said embodiment, it illustrated as a member with the large area of the 2nd conductor plates 35 and 36 with respect to the 1st conductor plates 33 and 34. FIG. However, the first conductor plates 33 and 34 and the second conductor plates 35 and 36 may be reversed in size or the same area. In short, a part of one conductor plate is important. May be disposed so as to protrude outward from one side edge of the other conductor plate, and the protrusions 71 and 71A to 71C may be disposed in this region.

In addition, the present invention is not limited to the above-described embodiment, and various modifications can be applied within the scope of the gist of the present invention.
In short, a part of the second conductor plate extends outward from one side edge of the first conductor plate, and a protrusion is disposed in the extended region of the second conductor plate. Any material can be used as long as it is covered with a sealing resin.

2 Wire 6 1st sealing resin 10A, 10B Power semiconductor unit 12 2nd sealing resin 24U, 24L Signal terminal (electrode terminal)
30 Power semiconductor module 31U, 31L Power semiconductor element 32U, 32L Diode 33, 34 Conductor plate (first conductor plate)
35, 36 Conductor plate (second conductor plate)
35A, 36A Conductor plate (second conductor plate)
35a DC positive terminal 36a AC output terminal 35c Positive lead (lead terminal)
36c Output lead (lead terminal)
40 Metal case 41a, 41b Heat radiation part 71, 71A-71C Protrusion 100, 100A-100C Power module

Claims (10)

A power semiconductor element having a first electrode on one side and a second electrode on the other side;
A first conductor plate joined to the one surface of the power semiconductor element;
A second conductor plate joined to the other surface of the power semiconductor element;
In the power semiconductor element, the first conductor plate, an insertion port for inserting the second conductor plate, a first heat radiating portion capable of conducting heat to the first conductor plate, and the second conductor plate A metal case that houses the power semiconductor element, the first conductor plate, and the second conductor plate having a second heat dissipating part capable of conducting heat;
A sealing resin that is housed in the metal case and surrounds an outer periphery of the power semiconductor element, the first conductor plate, and the second conductor plate;
A part of the second conductor plate extends outward from one side edge of the first conductor plate, and the sealing resin covers a portion covering the extended region of the second conductor plate. Have
A power module in which a protrusion protruding toward the first heat radiating plate is disposed in a portion of the sealing resin that covers an extended region of the second conductor plate. The power module according to claim 1,
And an electrode terminal, and a wire for electrically connecting the electrode terminal and the first electrode of the power semiconductor element, wherein at least a part of the electrode terminal and the wire are the second conductor. A power module covered with the sealing resin portion covering an extended region of the plate. The power module according to claim 1,
The protrusion is a power module provided on the second conductor plate. In the power module according to claim 3,
The projection is a power module formed integrally with the second conductor plate.   4. The power module according to claim 3, wherein the protrusion is a separate member from the second conductor plate, and is laminated and joined on the second conductor plate. 5. The power module according to claim 5,
The protrusion is a lead terminal connected to the second electrode of the power semiconductor element, and extends outward from a portion of the sealing resin that covers an extended region of the second conductor plate. A power module having a portion. The power module according to claim 1,
The protrusion has an upper surface facing the first heat radiating portion, and a gap is provided between the upper surface of the protrusion and the first heat radiating portion to substantially interpose the sealing resin. Not a power module. The power module according to any one of claims 1 to 6,
The projection has a top surface facing the first heat dissipation portion, and a power module in which a gap is provided between the top surface of the projection and the first heat dissipation portion to interpose the sealing resin. . The power module according to claim 8, wherein
The said clearance gap is a power module smaller than the thickness of a said 1st thermal radiation part. The power module according to claim 9, wherein
The power module, wherein the gap is about 1/3 or less of the thickness of the first heat radiating portion.

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