JP7171516B2 - Power semiconductor module, power converter, and method for manufacturing power semiconductor module - Google Patents

Description

The present invention relates to a power semiconductor module, a power converter, and a method of manufacturing a power semiconductor module.

2. Description of the Related Art A power semiconductor module having a switching element for power conversion has high conversion efficiency, so it is widely used for consumer use, vehicle use, railway use, substation equipment, and the like. Since this power semiconductor module generates heat when energized, high heat dissipation is required.
Conventionally, a power semiconductor module generally has a box shape in which front and back surfaces of an electric circuit body having switching elements are thermally coupled to a heat radiating member having heat radiating fins, and both side surfaces of the heat radiating member are connected by connecting members. there is Thermal coupling between the heat radiating member and the electric circuit is performed by inserting a resin member between the heat radiating member and the electric circuit. However, in this structure, excessive residual stress is generated in the connecting portion between the heat dissipating member and the connecting member, and cracks may occur in the connecting portion or peeling may occur at the connection interface.

For this reason, there is known a power semiconductor module having a structure in which an intermediate member that is curved so as to protrude toward the electric circuit body is provided at the joint between the heat radiating member and the connecting member. It is said that residual stress can be reduced by forming the curved portion (see, for example, Patent Document 1). However, the resin member that joins the heat radiating member and the electric circuit body is not connected to the intermediate member.

JP 2012-178484 A

In the power semiconductor module disclosed in Patent Document 1, the resin member that joins the heat radiating member and the electric circuit body is not connected to the intermediate member. Therefore, due to a temperature change, the heat radiating member may warp due to the difference in coefficient of thermal expansion between the heat radiating member and the electric circuit body, and the resin member may peel off.

A power semiconductor module according to a first aspect of the present invention includes an electric circuit body having a semiconductor element and a conductor, a heat radiating section having a heat radiating base and a plurality of fins, a supporting section for supporting the heat radiating section, and the heat radiating base. an intermediate portion connecting the supporting portion; and an interposed portion provided between the heat radiating base and the conductor and connecting the heat radiating portion and the conductor so as to allow heat conduction, wherein the intermediate portion is a deformed portion protruding toward the electric circuit body from a connection portion with the heat dissipation base; A portion is adhered to the deformed portion.
A method for manufacturing a power semiconductor module according to a second aspect of the present invention comprises preparing an electric circuit body having conductor elements and conductors, and connecting a heat dissipating portion having a plurality of fins and a heat dissipating base to a supporting portion at an intermediate portion. providing the intermediate portion with a deformed portion that protrudes from a connection portion with the heat dissipation base toward the electric circuit body; and connecting the heat dissipation base and the conductor by an interposing portion capable of conducting heat. and connecting the heat dissipating base and the conductor by an interposing portion capable of conducting heat, wherein the interposing portion extends to a region where the deformed portion of the intermediate portion is formed. providing an extension to the deformed portion; and bonding the extension to the deformed portion.

According to the present invention, it is possible to suppress peeling of the interposed portion that connects the heat radiating portion and the conductor.

1 is an external perspective view of an embodiment of a power semiconductor module according to the present invention; FIG. 2(a) is a cross-sectional view of the power semiconductor module shown in FIG. 1 taken along the IIa-IIa crimping jig line, and FIG. 2(b) is an enlarged view of region IIb of FIG. 2(a). 3 is a circuit diagram showing an example of a circuit of the power semiconductor module shown in FIG. 2; FIG. 4A to 4C are cross-sectional views for explaining a method of manufacturing the power semiconductor module shown in FIG. 1; FIG. 5 is a cross-sectional view for explaining the method of manufacturing the power semiconductor module continued from FIGS. 4(a) to 4(c); FIG. Fig.6 (a) is sectional drawing for analysis of the power semiconductor module of an Example, FIG.6(b) is sectional drawing for analysis of the power semiconductor module of a comparative example. FIG. 7 is a comparison diagram of generated stresses in a comparative example and an example by elasto-plastic analysis. FIG. 8 is an enlarged view of FIG. 2(b) and is a view for explaining adhesion between the interposing portion and the intermediate portion; FIG. 9 is a schematic diagram for explaining a cause of peeling of an interposed portion; 10(a) is an external perspective view of a power semiconductor device having the power semiconductor module illustrated in FIG. 1, and FIG. 10(b) is a cross-sectional view of the power semiconductor device of FIG. 10(a) along line Xb-Xb. perspective view. 11(a) is an external perspective view of a power semiconductor device having a flow path forming portion, and FIG. 11(b) is a perspective view of the power semiconductor device of FIG. 11(a) cut along line XIb-X1b. 11(c) is a perspective view of the power semiconductor device of FIG. 11(b) from which a flow path forming portion is removed; FIG. 12 is a circuit diagram of a power converter using the power semiconductor device according to the present invention; 13 is an external perspective view showing an example of the power converter shown in FIG. 12; FIG. 14 is a cross-sectional view taken along line XIV-XIV of the power converter shown in FIG. 13;

Embodiments of the present invention will be described below with reference to the drawings. The following description and drawings are examples for explaining the present invention, and are appropriately omitted and simplified for clarity of explanation. The present invention can also be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.
The position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc., in order to facilitate understanding of the invention. As such, the present invention is not necessarily limited to the locations, sizes, shapes, extents, etc., disclosed in the drawings.

FIG. 1 is an external perspective view of an embodiment of a power semiconductor module according to the present invention, FIG. 2(a) is a sectional view taken along line IIa-IIa of the power semiconductor module shown in FIG. b) is an enlarged view of region IIb of FIG. 2(a).
As illustrated in FIG. 1 , power semiconductor module 300 has a flat box-shaped case 310 that accommodates heat radiating portion 330 and electric circuit body 400 therein. case 310
A brim-shaped channel seal portion 335 is formed on the upper portion of the . The channel seal portion 335 has an annular groove, and when the power semiconductor module 300 is inserted into a channel forming body (not shown), the channel sealing portion 335 is watertightly fitted to the inner surface of the channel forming body.
The electric circuit body 400 has an electric circuit mounting portion housed in the case 310 and a terminal mounting portion protruding from the case 310 .

A plurality of power terminals for inputting/outputting a large current and a plurality of signal terminals for inputting/outputting a signal are provided in the terminal mounting portion of the electric circuit body 400 . As power terminals, it has a positive terminal 315B, a negative terminal 319B, and an AC terminal 320B. As signal terminals, it has an upper arm gate terminal 325U, a lower arm gate terminal 325L, a mirror emitter signal terminal 325M, a Kelvin emitter signal terminal 325K, a temperature sense signal terminal 325S, a mirror emitter signal terminal 325M, and a Kelvin emitter signal terminal 325K. Since the plurality of power terminals and the plurality of signal terminals protrude from one direction, the channel seal portion 335 can be easily formed. The positive electrode side terminal 315B and the negative electrode side terminal 319B are each branched into two and arranged adjacent to each other alternately. This has the effect of bringing the input and output currents closer together and reducing the inductance.

As shown in FIG. 2A, the case 310 includes a pair of upper and lower heat radiating portions 330, a pair of left and right support portions 334 connecting the pair of upper and lower heat radiating portions 330, and the heat radiating portion 330 and the support portion 334. It has an intermediate portion 333 to which it connects. The intermediate portions 333 are provided near four corners where the heat radiating portion 330 and the supporting portion 334 intersect, and connect the heat radiating portion 330 and the supporting portion 334 in the vicinity of the four corners. The case 310 constitutes a generally box-shaped housing portion that houses the electric circuit mounting portion of the electric circuit body 400 .

The heat dissipation part 330 has a plurality of pin-shaped fins 331 and a heat dissipation base 332 .
The electric circuit mounting portion of the electric circuit body 400 has a plurality of semiconductor elements 150 , collector-side conductors 431 , emitter-side conductors 430 and sealing resin 360 .

Interposed portions 440 are interposed between the upper heat radiating portion 330 and the emitter-side conductor 430 and between the lower heat radiating portion 330 and the collector-side conductor 431, respectively. Each interposed portion 440 is bonded to the heat dissipation base 332 and the emitter-side conductor 430 of the heat dissipation portion 330 or to the heat dissipation base 332 and the collector-side conductor 431 of the heat dissipation portion 330 .

The semiconductor element 150 and the emitter-side conductor 430, and the semiconductor element 150 and the collector-side conductor 431 are joined by a joining material 51 such as solder or sintered metal.

By sandwiching the semiconductor element 150 between the collector-side conductor 431 and the emitter-side conductor 430, heat dissipation from both surfaces of the semiconductor element 150 can be promoted. Si is often used as a material forming the semiconductor element 150, but SiC, GaN, GaO, or the like can also be used. The collector-side conductor 431 and the emitter-side conductor 430 are not particularly limited as long as they are made of a material having excellent electrical conductivity and thermal conductivity, but copper-based materials are preferable in terms of electrical conductivity, thermal conductivity and cost. The sealing resin 360 is not particularly limited as long as it is an insulating material, but a resin formed by transfer molding is preferable because of its excellent productivity.

As shown in FIG. 2B, the intermediate portion 333 has a V-shaped deformation portion 381 protruding toward the semiconductor element 150 side. The deformation portion 381 has an inner inclined portion 381 a connected to the heat radiation base 332 and an outer inclined portion 381 b connected to the support portion 334 . The intermediate portion 333 has less rigidity than the heat dissipation base 332 and the support portion 334 .

In addition, the interposed portion 440 has extension portions 440a further extending from both ends of the emitter-side conductor 430, as shown in FIG. 2(b). The extending portion 440a extends parallel to the lower surface of the heat dissipation base 332, contacts the inner inclined portion 381a of the deformed portion 381 of the intermediate portion 333, and is bent along the inner inclined portion 381a. The extension portion 440 a is adhered to the inner inclined portion 381 a of the deformation portion 381 . A region surrounded by the sealing resin 360, the intermediate portion 333 and the support portion 334 is a spatial region. That is, according to the structure of the present embodiment, peeling of the interposed portion 440 connecting the heat radiating portion 330 and the conductors 430 and 431 can be suppressed without filling resin or the like in this space region. This will be discussed later.

3 is a circuit diagram showing an example of a circuit of the power semiconductor module shown in FIG. 2. FIG.
The power semiconductor module 300 includes an upper arm circuit 305a having a switching function composed of an active element 155 and a diode 156, and a lower arm circuit 305b having a switching function composed of an active element 157 and a diode 158. FIG. As the active elements 155 and 157, transistors such as IGBTs (Insulated Gate Bipolar Transistors) and MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) are used. SBDs (Schottky Diodes), FRDs (Fast Recovery Diodes), etc. are used as the diodes 156 and 158 .

As illustrated in FIG. 3, the positive terminal 315B is connected to the collector conductor 431a. The collector electrode of active element 155 and the cathode electrode of diode 156, which constitute the switching element of the upper arm circuit, are electrically connected by collector-side conductor 431a. The emitter electrode of active element 155 and the anode electrode of diode 156 are electrically connected by emitter-side conductor 430a.

The negative terminal 319B is electrically connected to the emitter conductor 430b. The emitter electrode of active element 157 and the anode electrode of diode 158, which constitute the switching element of the lower arm circuit, are electrically connected by emitter-side conductor 430b. A collector electrode of the active element 157 and a cathode electrode of the diode 158 are electrically connected by a collector-side conductor 431b. The collector-side conductor 431b and the emitter-side conductor 430a are electrically connected via an intermediate electrode 414 (not shown in FIG. 2(a)). The AC-side terminal 320B is electrically connected to the collector-side conductor 431b. Kelvin emitter signal terminal 325K is connected to the emitter electrodes of each of the upper and lower arm circuits. The collector sense signal terminal 325C of the upper arm circuit is electrically connected to the collector side conductor 431a, and the collector sense signal terminal 325C of the lower arm circuit is connected to the collector side conductor 431b.
Active elements 155 and 157 and diodes 156 and 158 are hereinafter referred to as semiconductor element 150 . Also, the emitter-side conductors 430a, 430b and the collector-side conductors 431a, 431b are referred to as conductors 430, 431, respectively.

The power semiconductor module 300 illustrated in FIG. 2 has one upper arm circuit 305a and one lower arm circuit 305b. Accordingly, the power semiconductor module 300 illustrated in FIG. 2 is illustrated as a 2-in-1 package.

As shown in FIG. 2A, the heat radiating portion 330 is thermally coupled, in other words thermally coupled, to the conductors 430 and 431 by the interposed portion 440 . Therefore, the heat generated by the semiconductor element 150 is efficiently radiated from the heat radiation portion 330 via the conductor 430 or the conductor 431 and the interposed portion 440 . The intermediate portion 333 is made of a member having less rigidity than the heat radiation base 332 and the support portion 334 . Therefore, when the heat radiation base 332 is deformed such as warping due to heat or the like, it deforms together with the heat radiation base 332, thereby suppressing the generation of stress.
In addition, in this embodiment, there is provided an interposed portion peeling suppression structure that suppresses exfoliation of the interposed portion 440 due to the difference in coefficient of thermal expansion between the heat dissipation base 332 and the conductors 430 and 431 .
The structure for suppressing peeling of the interposed portion will be described below.

9A and 9B are schematic diagrams for explaining the factors of peeling of the interposed portion. FIG.
FIG. 9 shows a structure in which a conductor 430r and a heat dissipation base 332r are adhered by an interposing portion 440r. The conductor 430r, the heat dissipation base 332r, and the interposed portion 440r are sealed on one side with a sealing resin 360r. The conductor 430r is made of, for example, copper, which has low electrical resistance and good thermal conductivity. The heat dissipation base 332r is made of, for example, a material such as aluminum that has a higher coefficient of thermal expansion than copper. When the semiconductor element 150 is driven and heat is generated, the temperature of the electric circuit body 400 rises. For this reason, the heat dissipation base 332r made of aluminum, which has a larger thermal expansion coefficient than copper, has both side edges directed upward with respect to the central portion, in other words, on the opposite side of the conductor 430r (in the z direction in the drawing). Warp to protrude. Therefore, thermal stress in the peeling direction acts on the interposed portion 440r that bonds the conductor 430r and the heat dissipation base 332, and the interposed portion 440r may be peeled off.

In this embodiment, as described above, the interposing portion 440 has the extension portion 440a that abuts on the inner inclined portion 381a of the deformed portion 381 of the intermediate portion 333, and both ends of the extension portion 440a are connected to the heat radiation base. It is adhered to the deformation portion 381 of the intermediate portion 333 that deforms with the deformation of the intermediate portion 332 . Due to the deformation of the deformable portion 381 , the thermal stress acting on the interposed portion 440 bonding the heat dissipation base 332 and the intermediate portion 333 together is relaxed, and the exfoliation of the interposed portion 440 is suppressed.

The interposed portion 440 is made by kneading a high thermal conductivity filler with an insulating resin at a high density, and is a material that develops adhesiveness through a curing reaction. A sheet formed in advance may be used, or a paste may be applied on the electric circuit body 400 . From the viewpoint of heat dissipation, the thermal conductivity of the interposed portion 440 must be 5 W/mmk or more, preferably 10 W/mk or more. Since the interposed portion 440 is filled with a high thermal conductivity filler at a high density, it is brittle at room temperature before hardening and easily cracked when deformed, so care must be taken in handling it. This will be explained in the manufacturing method of the power semiconductor module.

The heat radiation base 332 and the fins 331 are not particularly limited as long as they are made of a material having high thermal conductivity, but copper-based or aluminum-based metal materials are preferable. When using a copper-based material, it is preferable to apply plating such as Ni in order to improve water resistance.

The supporting portion 334 is not particularly limited as long as it is made of a material having high rigidity. A copper-based, aluminum-based, or iron-based metal material, a resin material reinforced with a filler, or the like can be used. In order to improve water resistance, a coating such as Ni plating may be applied.

The intermediate portion 333 is not particularly limited as long as it is made of a material with low rigidity, but a material having excellent adhesion to the interposed portion 440 is preferable. Copper-based or aluminum-based metal materials, PPS (polyphenylene sulfide), PBT (polybutylene terephthalate), PA (polyamide), resin materials such as urethane resin, epoxy resin, and silicone resin can be used. In order to improve water resistance, a coating such as Ni plating may be applied.

The heat dissipation base 332, the support portion 334, and the intermediate portion 333 may be made of the same material or may be made of different materials. The intermediate portion 333 preferably has less rigidity than the heat radiation base 332 and the support portion 334 , and is formed thinner than the heat radiation base 332 and the support portion 334 when formed from the same material.
Next, an example of a method for manufacturing the power semiconductor module 300 will be described.

4(a) to 4(c) are cross-sectional views for explaining the method of manufacturing the power semiconductor module shown in FIG. 1, and FIG. It is sectional drawing for demonstrating the manufacturing method of a power semiconductor module which follows.
The collector-side conductor 431 and the semiconductor element 150 are bonded with the bonding material 51 , and the semiconductor element 150 and the emitter-side conductor 430 are bonded with the bonding material 51 . Then, the periphery of the collector-side conductor 431, the emitter-side conductor 430, and the semiconductor element 150 is sealed with a sealing resin 360 to fabricate the electrical circuit body 400 of the 2-in-1 package shown in FIG. 4(a). The upper surface 400 a and the lower surface 400 b of the electric circuit body 400 are not covered with the sealing resin 360 .

Next, as shown in FIG. 4B, the interposed portion 440 is temporarily fixed to each of the upper surface 400a and the lower surface 400b of the electric circuit body 400. Next, as shown in FIG. Temporary fixation may utilize the adhesiveness of the material itself, or may be thermocompression bonding at a temperature at which the uncured interposed portion 440 does not reach complete curing.

On the other hand, the case 310 in which the supporting portion 334, the heat radiation base 332, and the intermediate portion 333 are integrated, and an accommodating portion in which the electric circuit body 400 is accommodated is formed is prepared.
Then, as shown in FIG. 4(c), the electric circuit body 400 to which the interposed portion 440 is temporarily fixed is housed in the housing portion of the case 310, and the upper and lower interposed portions 440 are respectively arranged as upper and lower heat dissipating units. It is arranged at a position facing the base 332 .

Next, the case 310 accommodating the electric circuit body 400 with the temporarily fixed interposed portion 440 is set in the vacuum pressure bonding apparatus 600 shown in FIG. 5(a).
The vacuum crimping device 600 includes a pair of upper and lower crimping devices 601 . The upper and lower crimping devices 601 have the same structure.
The crimping device 601 includes a plurality of crimping jigs 603 , a pair of right and left deformation jigs 604 , a base portion 605 , a base portion 605 , and between each of the crimping jigs 603 and between each of the deformation jigs 604 . It has a resilient member 602 such as a compression spring provided.

The crimping jig 603 is a plate-like member, and presses the upper end surfaces of the fins 331 of the heat radiating section 330 against the conductors 430 and 431 . The crimping jig 603 has a projecting portion 604a and a flat portion 604b at the end opposite to the base portion 605 side. The flat portion 604b is provided closer to the base portion 605 than the tip of the projecting portion 604a. That is, the flat portion 604b is formed at the base of the protruding portion 604a, and there is a step of the height of the protruding portion 604a between the flat portion 604b and the tip of the protruding portion 604a.

As shown in FIG. 5( a ), in a state where the case 310 housing the electric circuit body 400 is set in the vacuum pressure bonding device 600 , the inside of the vacuum pressure bonding device 600 is heated to a temperature higher than the softening temperature of the interposed portion 440 . For example, it is heated to 120° C. or higher.
The interposed portion 440 before hardening is brittle at room temperature and may be damaged if deformed. However, when heated to a softening temperature or higher, the interposed portion 440 becomes flexible and can be deformed without being damaged.

After that, as shown in FIG. 5(b), the vacuum crimping device 600 is clamped. Due to the clamping of the vacuum crimping device 600, the base portion 605 moves (lowers or rises) toward the case 310 in which the electric circuit body 400 is accommodated. As a result, each crimping jig 603 presses the upper surfaces of the fins 331 arranged in the opposing regions, and thermally crimps the interposing portion 440 between the heat dissipation base 332 and the conductors 430 and 431 . Therefore, the heat radiation base 332 and the conductors 430 and 431 are adhered and thermally coupled by the interposing portion 440 .

Further, due to the movement of the base portion 605, the intermediate portion 333 is pressed by the protruding portion 604a of the deforming jig 604 and protrudes toward the semiconductor element 150, forming the deforming portion 381. As shown in FIG. The deformation jig 604 is restricted from moving toward the semiconductor element 150 by abutting the flat portion 604 b on the upper surface of the peripheral portion of the heat dissipation base 332 .

By thermally compressing the heat radiation base 332 and the intermediate portion 333 with the crimping jig 603 and the deforming jig 604 at a temperature equal to or higher than the softening temperature of the interposing portion 440, a part of the interposing portion 440 is also attached to the extending portion 440a. It flows and comes into contact with the inner inclined portion 381 a of the deformation portion 381 .
The inside of the vacuum pressure bonding device 600 is heated to, for example, about 180° C. to advance the curing reaction of the interposed portion 440 , and after the adhesive force is developed, the interposed portion 440 is cooled and cured.

After that, the mold of the vacuum pressure bonding device 600 is opened, and as shown in FIG. 2 can be obtained.

The crimping jig 603 of the vacuum crimping apparatus 600 has a structure in which the fins 331 provided on the entire area of the heat dissipation base 332 are divided into a plurality of areas, and each area faces the fins 331 provided in one divided area. there is Therefore, even if the height of the fins 331 varies, or if the height position of the fins 331 varies due to the warp of the heat radiation base 332, the interposed portion 440 can be provided with the necessary power through the fins 331. It is possible to apply surface pressure.

Further, the deformation jig 604 has a protruding portion 604 a that applies a constant pressure to the intermediate portion 333 and a flat portion 604 b that crimps a portion of the intermediate portion 333 near the connection portion with the heat dissipation base 332 . The movement of the deformation jig 604 toward the semiconductor element 150 is stopped when the flat portion 604b comes into contact with the upper surface of the peripheral edge portion of the heat radiation base 332 . Therefore, the amount of projection of the deformation portion 381 formed in the intermediate portion 333 can be controlled to be constant, and damage due to excessive deformation can be prevented.

Moreover, since the portion of the intermediate portion 333 near the connection portion with the heat dissipation base 332 is crimped, the effect of suppressing the peeling of the heat dissipation base 332 from the interposing portion 440 due to warping can be improved.

[Example]
A power semiconductor module 300 having a structure illustrated in FIG. 6(a) was produced. The structure of the power semiconductor module 300 is the same as the structure illustrated in FIGS. 2(a) and 2(b). An intermediate portion 333 connecting the heat radiation base 332 and the support portion 334 is formed thinner than the heat radiation base 332 and the support portion 334 and has a deformation portion 381 . The heat radiation base 332, the support portion 334 and the intermediate portion 333 are made of pure aluminum. Conductors 430 and 431 are made of pure copper. The sealing resin 360 and the interposed portion 440 were formed of filler-containing resin having the same coefficient of thermal expansion as pure copper. The Young's modulus of the sealing resin 360 is 14 GPa, and the Young's modulus of the interposed portion 440 is 18 GPa. Further, the glass transition temperature Tg of the sealing resin 360 is 175°C, and the glass transition temperature Tg of the interposed portion 440 is 150°C.
About the power semiconductor module 300, environmental temperature was changed from normal temperature to 175 degreeC, and the generated stress of the analysis point Y was elastic-plastic-analyzed.

[Comparative example]
A power semiconductor module 300R of a comparative example having the structure illustrated in FIG. 6B was produced. The power semiconductor module 300R of the comparative example has a flat intermediate portion 333r connecting the heat dissipation base 332 and the support portion 334, and does not have the deformed portion 381 of the power semiconductor module 300 of the embodiment. In the power semiconductor module 300R of the comparative example, the intermediate portion 333r is formed thinner than the heat radiation base 332 and the support portion 334 as well. Everything other than the above is the same as the power semiconductor module 300 of the embodiment.
Also for the power semiconductor module 300R of the comparative example, the environmental temperature was changed from room temperature to 175° C., and the generated stress at the analysis point Y was subjected to elastoplastic analysis.

FIG. 7 is a comparison diagram of generated stresses in comparative examples and examples by elastic-plastic analysis. FIG. 7 shows the value of the maximum principal stress at the analysis point Y of the power semiconductor module 300R of the example as a relative value, with the value of the maximum principal stress at the analysis point Y of the power semiconductor module 300R of the comparative example being 100%. It is a thing.
As shown in FIG. 7, the maximum principal stress generated at the analysis point Y in the power semiconductor module 300 of the example is reduced to about 30% of that in the power semiconductor module 300R of the comparative example.
Therefore, the reason for reducing the stress generated in the intermediate portion 333 in the embodiment is that the extending portion 440a of the interposed portion 440 is adhered to the inner inclined portion 381a of the deformable portion 381 of the intermediate portion 333. was confirmed.

FIG. 8 is an enlarged view of FIG. 2(b), and is a view for explaining the bonding between the interposing portion and the intermediate portion.
An extending portion 440 a of the interposed portion 440 extends parallel to the lower surface of the heat dissipation base 332 . The extension portion 440a is in contact with and adhered to the inner inclined portion 381a of the deformation portion 381 . Therefore,
The z-direction thickness w at which the extending portion 440a of the interposing portion 440 is adhered to the inner inclined portion 381a of the deforming portion 381 is determined by It is preferably equal to or greater than the thickness x in the z direction at the position corresponding to the joint v (w≧x).
In other words, as shown in FIG. 8, the z-direction thickness w at which the extending portion 440a of the interposing portion 440 is adhered to the inner inclined portion 381a of the deforming portion 381 is equal to the extension of the interposing portion 440. The z-direction thickness x of the portion 440a at the position corresponding to the junction v of the intermediate portion 333 with the heat dissipation base 332 is projected onto the deformation portion 381 by projection light parallel to the extending direction of the interposed portion 440. It is preferably equal to or greater than the projection z-direction thickness w. As a result, the extension portion 440a of the interposed portion 440 and the deformable portion 381 can be adhered efficiently and reliably.

According to the above embodiment, the following effects are obtained.
(1) The power semiconductor module 300 includes an electric circuit body 400 having a semiconductor element 150 and conductors 430 and 431, a heat dissipation portion 330 having a heat dissipation base 332 and a plurality of fins 331, a support portion 334 supporting the heat dissipation portion 330, Interposed portion 440 provided between heat dissipation base 332 and conductors 430 and 431 to connect heat dissipation portion 330 and conductors 430 and 431 in a heat conductive manner, and an intermediate portion connecting heat dissipation base 332 and support portion 334 333. The intermediate portion 333 has a deformed portion 381 that protrudes toward the electric circuit body 400 from the connection portion with the heat dissipation base 332, and the interposed portion 440 has an extension portion 440a that contacts the deformed portion 381 of the intermediate portion 333. , and the extension portion 440 a is adhered to the deformation portion 381 .
In addition, the method of manufacturing a power semiconductor module includes preparing an electric circuit body 400 having a semiconductor element 150 and conductors 430 and 431, and disposing a heat dissipating portion 330 having a plurality of fins 331 and a heat dissipating base 332 and a supporting portion 334 in the middle. connecting at the portion 333; providing the intermediate portion 333 with a deformed portion 381 projecting from the connection portion with the heat dissipation base 332 toward the electric circuit body 400; connecting the heat dissipating base 332 and the conductors 430 and 431 with the heat conductive interposer 440 , connecting the interposer 440 to the intermediate portion 333 ; It includes providing an extension portion 440 a extending to a region where the deformation portion 381 is formed, and bonding the extension portion 440 a to the deformation portion 381 . Therefore, peeling of the interposed portion 440 that connects the heat radiating portion 330 and the conductors 430 and 431 can be suppressed.

(2) the coefficient of thermal expansion of the heat dissipation base 332 is greater than the coefficient of thermal expansion of the conductors 430 and 431; Therefore, the heat generated by the semiconductor element 150 causes the temperature of the electric circuit body 400 to rise, and the heat radiation base 332 is warped such that the connection portion side of the heat radiation base 332 with the intermediate portion 333 is separated from the conductors 430 and 431. Even in this case, peeling of the interposed portion 440 that connects the heat radiating portion 330 and the conductors 430 and 431 can be suppressed.

(3) The deformed portion 381 of the intermediate portion 333 includes an inner inclined portion 381a extending from the heat radiation base 332 toward the support portion 334, and an end portion of the inner inclined portion 381a extending toward the support portion 334. and an outer inclined portion 381b. In other words, the intermediate portion 333 has a V-shaped cross-sectional shape. Therefore, residual stress generated in the heat radiation base 332 can be reduced.

(4) The z-direction thickness w at which the extending portion 440a of the interposed portion 440 is adhered to the inner inclined portion 381a of the deformable portion 381 is It is equal to or greater than the thickness x in the z direction at the position corresponding to the junction v with 332 (w≧x). Therefore, the thickness of adhesion between the extending portion 440a of the interposed portion 440 and the interposed portion 440, in other words, the adhesion strength can be increased.

(5) Furthermore, the electric circuit body 400 has a facing heat dissipation portion 330 provided on the side facing the heat dissipation portion 330 and connected to the support portion 334 . A region surrounded by the intermediate portion 333, the support portion 334, and the sealing resin 360 is a spatial region. As described above, even if the area surrounded by the intermediate portion 333, the support portion 334, and the sealing resin 360 is not filled with a filler such as a resin and is left as a space, the heat radiating portion 330 and the conductors 430 and 431 are connected. Separation of the interposed portion 440 to be connected can be suppressed. Therefore, a step of filling resin or the like in the space region can be omitted, and productivity can be improved.

FIG. 10(a) is an external perspective view of a power semiconductor device having the power semiconductor module shown in FIG. 1, and FIG. 10(b) shows the power semiconductor device of FIG. It is a perspective view cut at .
A power semiconductor device 700 is obtained by integrating three power semiconductor modules 300 shown in FIG. Power semiconductor device 700 includes three power semiconductors that extend case 310A in the arrangement direction of power semiconductor modules 300 and house three electric circuit bodies 400 and a pair of heat radiating parts 330 sandwiching each electric circuit body 400. This is a shared case for module 300 . The channel seal portion 335A is formed in an annular shape on the outer periphery of the entire case 310A, which is a common case for the three power semiconductor modules 300. As shown in FIG.

As shown in FIG. 10(b), two intermediate portions 333 connected to the heat radiation bases 332 of the power semiconductor modules 300 on both sides are formed on the supporting portion 334A provided between the adjacent power semiconductor modules 300. It is A deformation portion 381 is provided in each of the intermediate portions 333 . In addition, each power semiconductor module 300 has an interposed portion separation suppression structure having an interposed portion 440 that thermally couples the heat dissipation base 332 and the conductors 430 and 431 . That is, as shown in FIGS. 2A and 2B, the extending portion 440a of the interposed portion 440 is adhered to the deformable portion 381 of the intermediate portion 333. As shown in FIGS. Therefore, the three power semiconductor modules 300 forming the power semiconductor device 700 respectively have the effects (1) to (5) of the embodiment.

By providing a control unit (not shown) for controlling the three power semiconductor modules 300 constituting the power semiconductor device 700 to output three-phase AC power of U-phase, V-phase, and W-phase, respectively, The power semiconductor device 700 can be, for example, a power conversion device that supplies three-phase AC power to a load such as a motor generator.
Since power semiconductor device 700 integrates three power semiconductor modules 300 , productivity can be improved compared to the case where three power semiconductor modules 300 are used to drive a motor generator.

11(a) is an external perspective view of a power semiconductor device having a flow path forming portion, and FIG. 11(b) is a perspective view of the power semiconductor device of FIG. 11(a) cut along line XIb-X1b. , and FIG. 11C is a perspective view of the power semiconductor device of FIG.
The power semiconductor device 700A is the power semiconductor device 700 shown in FIG. The flow path forming portion 710 has a case body 711 (see FIG. 11B), an upper cover 712 and a lower cover 713 .

The upper cover 712 is provided to cover the fins 331 of the heat radiating section 330 on the upper side of the three power semiconductor modules 300 . Between the upper cover 712 and the heat radiating section 330 on the upper side, an upper flow path 721 through which the coolant flows is provided. A peripheral portion of the upper cover 712 is joined to the case body 711 by welding such as laser welding.
The lower cover 713 is provided so as to cover the fins 331 of the heat radiating section 330 on the lower side of the three power semiconductor modules 300 . Between the lower cover 713 and the heat radiating section 330 on the lower side, a lower flow path 722 through which the coolant flows is provided. A peripheral portion of the lower cover 713 is joined to the case body 711 by welding such as laser welding.

The case body 711 has an outer wall 711a on the outside of each of the support portions 334 on both end sides in the arrangement direction of the power semiconductor modules 300 . A vertical communication channel 723 is formed between the outer wall 711 a and the support portion 334 .

A coolant inlet 713a is provided at one longitudinal end of the lower cover, and a coolant outlet 713b is provided at the other longitudinal end of the lower cover. The coolant that has flowed into the lower flow path 722 from the inlet 713a flows between the fins 331 of the heat radiating section 330 on the lower side, and cools the electrical circuit mounting section of the electrical circuit body 400 . In addition, the cooling liquid that has flowed into the lower flow path 722 flows into the upper flow path 721 via the vertical communication flow path 723, flows between the fins 331 of the heat radiation portion 330 on the upper side, and cools the electric circuit body 400. Cool the circuit mounting part.
The flow path forming portion 710 of the above embodiment can be made watertight by simply welding the upper cover 712 and the lower cover 713 to the case body 711 by laser welding or the like. Therefore, productivity of the power semiconductor device 700A having the flow path forming portion 710 can be improved.

FIG. 12 is a circuit diagram of a power converter using the electric circuit device according to the present invention.
The power converter 200 includes inverter circuit units 140 and 142 , an auxiliary inverter circuit unit 43 , and a capacitor module 500 . The inverter circuit units 140 and 142 are provided with a plurality of power semiconductor modules 300, which are connected to form a three-phase bridge circuit. When the current capacity is large, the power semiconductor modules 300 are further connected in parallel, and these parallel connections are made corresponding to each phase of the three-phase inverter circuit, so that the current capacity can be increased. Also, the current capacity can be increased by connecting in parallel the active elements 155 and 157 and the diodes 156 and 158 which are power semiconductor elements built in the power semiconductor module 300 .

The inverter circuit section 140 and the inverter circuit section 142 have basically the same circuit configuration, and basically have the same control method and operation. Since the outline of the circuit-like operation of the inverter circuit unit 140 and the like is well known, detailed description thereof will be omitted here.
As described above, the upper arm circuit includes the upper arm active element 155 and the upper arm diode 156 as switching power semiconductor elements, and the lower arm circuit includes the lower arm circuit as switching power semiconductor elements. It has an active element 157 for the arm and a diode 158 for the lower arm. The active elements 155 and 157 receive drive signals output from one or the other of the two driver circuits forming the driver circuit 174 and perform switching operations to convert the DC power supplied from the battery 136 into three-phase AC power. .

As described above, the upper arm active element 155 and the lower arm active element 157 have collector electrodes, emitter electrodes, and gate electrodes. The diode 156 for the upper arm and the diode 158 for the lower arm have two electrodes, a cathode electrode and an anode electrode. As shown in FIG. 3, the cathode electrodes of diodes 156 and 158 are electrically connected to the collector electrodes of IGBTs 155 and 157, and the anode electrodes are electrically connected to the emitter electrodes of active elements 155 and 157, respectively. As a result, the current flows in the forward direction from the emitter electrode to the collector electrode of the active element 155 for the upper arm and the active element 157 for the lower arm.
A MOSFET (metal oxide semiconductor field effect transistor) may be used as the active element, and in this case, the diode 156 for the upper arm and the diode 158 for the lower arm are not required.

The positive terminal 315B and the negative terminal 319B of each upper and lower arm series circuit are connected to DC terminals for capacitor connection of the capacitor module 500, respectively. AC power is generated at the connecting portion of the upper arm circuit and the lower arm circuit, respectively, and the connecting portion of the upper arm circuit and the lower arm circuit of each upper and lower arm series circuit is connected to the AC side terminal 320B of each power semiconductor module 300. It is AC side terminals 320B of each power semiconductor module 300 of each phase are connected to AC output terminals of power converter 200, and the generated AC power is supplied to the stator windings of motor generator 192 or 194. FIG.

The control circuit 172 controls the switching timing of the active element 155 for the upper arm and the active element 157 for the lower arm based on input information from a vehicle-side control device or sensor (for example, the current sensor 180). Generate timing signals. Based on the timing signal output from the control circuit 172, the driver circuit 174 generates drive signals for switching the active element 155 for the upper arm and the active element 157 for the lower arm.
181, 182 and 188 are connectors.

The upper/lower arm series circuit includes a temperature sensor (not shown), and temperature information of the upper/lower arm series circuit is input to the microcomputer. Also, voltage information on the DC positive side of the upper and lower arm series circuits is input to the microcomputer. Based on this information, the microcomputer detects overtemperature and overvoltage, and when overtemperature or overvoltage is detected, switches all the active elements 155 for the upper arm and the active elements 157 for the lower arm. It stops and protects the upper and lower arm series circuits from over temperature or over voltage.

13 is an external perspective view showing an example of the power converter shown in FIG. 12, and FIG. 14 is a cross-sectional view of the power converter shown in FIG. 13 taken along line XIV-XIV.
The power conversion device 200 includes a housing 12 which is composed of a lower case 11 and an upper case 10 and is formed in a substantially rectangular parallelepiped shape. The housing 12 accommodates an electric circuit body 400, a capacitor module 500 (see FIG. 12), and the like. The electric circuit body 400 has a cooling flow path, and a cooling water inflow pipe 13 and a cooling water outflow pipe 14 that communicate with the cooling flow path protrude from one side surface of the housing 12 .

As shown in FIG. 13, the lower case 11 has an opening on the upper side, and the upper case 10 is attached to the lower case 11 so as to close the opening of the lower case 11 . The upper case 10 and the lower case 11 are made of an aluminum alloy or the like, and are hermetically fixed to the outside. The upper case 10 and the lower case 11 may be integrally configured. By forming the housing 12 into a simple rectangular parallelepiped shape, it is easy to attach to a vehicle or the like, and it is easy to manufacture.

A connector 17 is attached to one side surface of the housing 12 , and an AC terminal 18 is connected to this connector 17 . A connector 21 is provided on the surface from which the cooling water inflow pipe 13 and the cooling water outflow pipe 14 are led out.

As illustrated in FIG. 14 , a power semiconductor device 700 is housed inside the housing 12 .
A control circuit 172 and a driver circuit 174 are arranged above the power semiconductor device 700 , and a capacitor module 500 is accommodated below the power semiconductor device 700 . The AC side terminal 320B of the power semiconductor module 300 penetrates the current sensor 180 and is joined to the bus bar 361 . A positive terminal 315B and a negative terminal 319B, which are DC terminals of the power semiconductor module 300, are connected to the positive and negative terminals 362A and 362B of the capacitor module 500, respectively.
In addition, in the power semiconductor module 300 shown in FIG. 1, the AC-side terminal 320B is not bent and extends straight. Moreover, the positive electrode side terminal 315B and the negative electrode side terminal 319B have a short shape cut at the root side.

In the above embodiment, the deformed portion 381 of the intermediate portion 333 is exemplified as a member having a V-shaped cross section having an inner inclined portion 381a and an outer inclined portion 381b. However, the deformed portion 381 of the intermediate portion 333 may be a member having U-shaped cross sections on the inner and outer sides. In the case of the V-shaped cross section, the inclination angles of the inner inclined portion 381a and the outer inclined portion 381b may be the same or different. In the case of a U-shaped cross section, the curvature of curvature may be the same or different. Moreover, the inner side and the outer side may each have a flat portion and a curved portion.

In the above-described embodiment, the case 310 has a structure in which the intermediate portion 333 having the deformed portion 381 is formed above and below the electric circuit body 400 . However, the present invention can be widely applied to structures in which the heat dissipation base 332 is thermally coupled to one side of the electric circuit body 400 .

Although various embodiments and modifications have been described above, the present invention is not limited to these contents. The various embodiments and modifications described above may be combined or modified as appropriate, and other aspects conceivable within the scope of the technical idea of the present invention are also included within the scope of the present invention.

150 Semiconductor element 172 Control circuit 174 Driver circuit 200 Power converter 300 Power semiconductor module 310, 310A Case 330 Heat dissipation part 331 Fin 332 Heat dissipation base 333 Intermediate part 334, 334A Support part 360 Sealing resin 381 Deformed part 381a Inner inclined part 381b Outside Inclined portion 400 Electric circuit bodies 430, 430a, 430b Emitter-side conductors 431, 431a, 431b Collector-side conductor 440 Interposed portion 440a Extension portion 500 Capacitor modules 700, 700A Power semiconductor device 710 Flow path forming portion 711 Case body

Claims (9)

an electrical circuit body having a semiconductor element and a conductor;
a heat dissipation part having a heat dissipation base and a plurality of fins;
a supporting portion that supports the heat radiating portion;
an intermediate portion that connects the heat dissipation base and the support portion;
an interposed portion provided between the heat dissipation base and the conductor, and connecting the heat dissipation portion and the conductor in a heat conductive manner;
the intermediate portion has a deformed portion protruding from a connection portion with the heat dissipation base toward the electric circuit body;
In the power semiconductor module, the interposing portion has an extending portion that abuts on the deforming portion of the intermediate portion, and the extending portion is adhered to the deforming portion. In the power semiconductor module according to claim 1,
The power semiconductor module, wherein the coefficient of thermal expansion of the heat dissipation base is greater than the coefficient of thermal expansion of the conductor. In the power semiconductor module according to claim 1,
The deformed portion of the intermediate portion includes an inner slope portion extending from the heat dissipation base toward the support portion and an outer slope portion extending from an end of the inner slope portion toward the support portion. A power semiconductor module having In the power semiconductor module according to claim 1,
The thickness at which the extending portion of the interposing portion is bonded to the inner inclined portion of the deforming portion is at a position corresponding to the joint portion of the extending portion of the interposing portion with the heat dissipation base of the intermediate portion. power semiconductor modules whose thickness is equal to or greater than the thickness of In the power semiconductor module according to claim 1,
further comprising a facing heat radiating portion provided on a side facing the heat radiating portion of the electric circuit body and connected to the supporting portion;
The electric circuit body has a sealing resin that seals the semiconductor element and the conductor,
A power semiconductor module in which a region surrounded by the intermediate portion, the support portion, and the sealing resin is a spatial region. In the power semiconductor module according to claim 1,
The power semiconductor module, wherein the intermediate portion has lower rigidity than the heat radiation base and the support portion. a power semiconductor module according to any one of claims 1 to 6;
and a control unit that controls the semiconductor element of the power semiconductor module to perform power conversion. providing an electrical circuit having semiconductor elements and conductors;
connecting a heat dissipating portion having a plurality of fins and a heat dissipating base and a supporting portion at an intermediate portion;
providing the intermediate portion with a deformed portion projecting from a connection portion with the heat dissipation base toward the electric circuit body;
connecting the heat dissipating base and the conductor with an interposed portion capable of conducting heat;
Connecting the heat dissipating base and the conductor by means of an interposed portion capable of conducting heat includes providing the interposed portion with an extension portion extending to a region where the deformed portion of the intermediate portion is formed, A method of manufacturing a power semiconductor module, including bonding the extension portion to the deformation portion. In the method for manufacturing a power semiconductor module according to claim 8,
Connecting the heat dissipating portion having the plurality of fins and the heat dissipating base and the supporting portion at the intermediate portion means forming a case in which the heat dissipating base and the supporting portion are connected and integrated by the intermediate portion. A method of manufacturing a power semiconductor module comprising:

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