JP2015233094A - Semiconductor module cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure high peeling strength compared to a conventional cooler in a joint part between a PPS resin molding and an aluminum plate which form a coolant passage.SOLUTION: A semiconductor module cooler 1 includes a PPS resin molding 2 in which a groove part 2a is formed and an aluminum plate 3 covering the groove part 2a. A coolant passage 5 is formed by the groove part 2a and the aluminium plate 3. A semiconductor module 10 contacting with the aluminum plate 3 is cooled by a cooling medium circulating in the coolant passage 5. The PPS resin molding 2 and the aluminum plate 3 are joined through an elastic body 4.

Description

  The present invention relates to a technology of a semiconductor module cooler, which is a cooler for cooling a semiconductor module, and more particularly to a technology for ensuring a peel strength between members constituting a cooling water channel formed in a semiconductor module. .

Conventionally, a semiconductor module cooler, which is a cooler for cooling a semiconductor module, has been used. For example, the one shown in Patent Document 1 below is known.
The conventional semiconductor module cooler disclosed in Patent Document 1 includes a cooling water channel that circulates a cooling medium (coolant liquid) in the cooler, and the cooling water channel has a semiconductor module with respect to a resin molded product. It forms by joining the metal plate which covers. In the conventional semiconductor module cooler, the material of the resin molded product is PPS (polyphenylene sulfide), the material of the metal plate is aluminum, and the aluminum plate (hereinafter referred to as the aluminum plate) is joined to the PPS resin molded product. Thus, a configuration for forming a cooling water channel is widely adopted.

JP 2012-99748 A

Since the conventional semiconductor module cooler is configured to circulate a relatively high-pressure cooling medium in the cooling water channel, high peel strength is required at the joint between the PPS resin molded product and the aluminum plate.
In a conventional semiconductor module cooler, an aluminum plate is directly joined to a PPS resin molded product to form a cooling water channel. However, in such a configuration, a sufficient amount of bonding is required at the joint between the PPS resin molded product and the aluminum plate. It was difficult to ensure peel strength.

  The present invention has been made in view of such a current problem, and it is possible to ensure a high peel strength as compared with the prior art at the joint between the PPS resin molded product and the aluminum plate constituting the cooling water channel. An object of the present invention is to provide a semiconductor module cooler.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in claim 1, the PPS resin molded product in which the groove portion is formed and an aluminum plate that covers the groove portion, a cooling water channel is formed by the groove portion and the aluminum plate, and the cooling water flowing through the cooling water channel A semiconductor module cooler for cooling a semiconductor module in contact with the aluminum plate by a medium, wherein the PPS resin molded product and the aluminum plate are joined via an elastic body.

  As effects of the present invention, the following effects can be obtained.

  According to the first aspect, the peel strength of the aluminum plate with respect to the PPS resin molded product can be increased as compared with the case where the PPS resin molded product and the aluminum plate are directly joined.

The schematic diagram which shows the whole structure of the semiconductor module cooler which concerns on one Embodiment of this invention, (a) Perspective schematic diagram, (b) The perspective schematic diagram which shows the disassembled state. The perspective schematic diagram which shows the aluminum plate which provided the elastic body which comprises the semiconductor module cooler which concerns on one Embodiment of this invention. The schematic diagram which shows the detailed form of the semiconductor module cooler which concerns on one Embodiment of this invention, (a) Cross-sectional schematic diagram, (b) Perspective schematic diagram. The cross-sectional schematic diagram which shows the specification state in the case of using combining multiple semiconductor module coolers. The figure which shows the measurement result (with and without an elastic body) of the peeling strength of a PPS material and an aluminum plate, (a) The graph which shows a measurement result, (b) The measurement piece (with and without an elastic body) Pattern diagram.

Next, embodiments of the invention will be described.
First, the overall configuration of a semiconductor module cooler according to an embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 1A, a semiconductor module cooler 1 according to an embodiment of the present invention is a cooler for cooling a semiconductor module 10 and includes a PPS resin molded product 2 and an aluminum plate 3. .
The semiconductor module cooler 1 is configured to form the cooling water channel 5 by joining the PPS resin molded product 2 and the aluminum plate 3 via the elastic body 4.

The PPS resin molded product 2 is a member molded by injection molding a PPS resin having high rigidity and excellent chemical resistance, and has a groove 2a as shown in FIG. 1B.
As shown in FIG. 1 (a), the groove portion 2a constitutes a bottom portion of the cooling water channel 5 and a pair of side portions, and both end portions in the length direction of the groove portion 2a and the surface facing the bottom portion are open. Has been.
In addition, although the groove part 2a shown by this embodiment has a substantially rectangular cross-sectional shape, the shape of the groove part 2a formed in the PPS resin molded product 2 which comprises the semiconductor module cooler 1 is not limited to this.

The aluminum plate 3 is a member that constitutes a portion that directly contacts the semiconductor module 10 that is an object to be cooled, and aluminum having a relatively high heat transfer coefficient is selected as a material.
Then, as shown in FIG. 1 (b), the aluminum plate 3 closes the surface facing the bottom of the groove 2a, so that the length of the groove 2a is directed as shown in FIG. 1 (a). Thus, the cooling water passage 5 communicating with each other is formed.
In the present embodiment, the aluminum plate 3 made of aluminum is used. However, the semiconductor module cooler can be configured by using a metal plate other than aluminum.

The elastic body 4 is a member interposed at the joint between the PPS resin molded product 2 and the aluminum plate 3 and is arranged to relieve internal stress generated when the PPS resin molded product 2 and the aluminum plate 3 are joined. is there.
More specifically, when the PPS resin molded product 2 and the aluminum plate 3 are joined, when the PPS resin molded product 2 cools and contracts, the PPS resin molded product 2 and the aluminum plate 3 are caused to have a difference in linear expansion coefficient. Internal stress is generated in the resin molded product 2. By interposing the elastic body 4 between the PPS resin molded product 2 and the aluminum plate 3, it is possible to absorb the influence due to the difference in linear expansion coefficient, thereby joining the PPS resin molded product 2 and the aluminum plate 3. Internal stress that occurs sometimes can be relieved.

As the material of the elastic body 4, a material that has good elongation and good reactivity with aluminum and PPS resin is selected.
Further, as the material of the elastic body 4, it is preferable to use a material having an elongation at break of 600% or more and a material having an epoxy group or a maleic anhydride group at the end of the molecular structure. Is preferred.
In this embodiment, as the material of the elastic body 4, a modified polyethylene (hereinafter also referred to as a modified PE) having an elongation at break of 600% or more and having a glycidyl methacrylate at the end of the molecular structure is employed.

The elastic body 4 is previously applied to the aluminum plate 3 by injection-molding the modified PE with a predetermined thickness.
When the modified PE is injection molded to the aluminum plate 3, it is preferable to form fine concave portions on the surface of the aluminum plate 3 for the purpose of improving the peel strength, or on the surface of the aluminum plate 3. It is preferable to apply a silane coupling agent and add an OH group.

Next, a more detailed embodiment of the semiconductor module cooler 1 will be described with reference to FIGS.
As shown in FIG. 2, a layer of modified PE elastic body 4 is formed in advance on the aluminum plate 3 constituting the semiconductor module cooler 1 by injection molding. The layer of the elastic body 4 made of modified PE is formed at least at the joint portion of the aluminum plate 3 with the PPS resin molded product 2.
Incidentally, the aluminum plate 3 constituting the semiconductor module cooler 1 has a plurality of cooling fins 6, 6... On the surface in contact with the cooling medium, as shown in FIG. Is preferably formed. The cooling fins 6 are implanted on the surface of the aluminum plate 3 opposite to the surface in contact with the semiconductor module 10, that is, on the surface in contact with the cooling medium.

FIGS. 3A and 3B show a semiconductor module cooler 1 manufactured by joining an aluminum plate 3 to a PPS resin molded product 2.
For joining the PPS resin molded product 2 and the aluminum plate 3 in the semiconductor module cooler 1, a mold for injection-molding the PPS resin molded product 2 on the aluminum plate 3 to which the elastic body 4 made of modified PE is applied in advance. It is set by injecting each member 2, 3, 4 while melting the modified PE, and then integrating them by injection molding.

  The aluminum plate 3 is arranged at a predetermined position of the PPS resin molded product 2 with the cooling fins 6 facing inward so that the cooling fins 6 are arranged in the cooling water channel 5, and the PPS is interposed via the elastic body 4. Joined to the resin molded product 2 (more specifically, injection welding). By disposing the cooling fins 6 continuous from the aluminum plate 3 in the cooling water channel 5, heat can be radiated more efficiently from the semiconductor module 10 (not shown in FIG. 3) in contact with the aluminum plate 3.

  Further, as shown in FIG. 3A, the semiconductor module cooler 1 shown in the present embodiment has a configuration in which the aluminum plates 3 and 3 are arranged on both upper and lower surfaces of the PPS resin molded product 2. In addition, in FIG.3 (b), illustration of the aluminum plate 3 of a lower surface side is abbreviate | omitted.

  The semiconductor module cooler 1 in which the aluminum plates 3 and 3 are arranged on both the upper and lower surfaces of the PPS resin molded product 2 can be used in a state where a plurality of the laminated plates are stacked as shown in FIG. In FIG. 4, illustration of the elastic body 4 and the cooling fin 6 is omitted.

  As shown in FIG. 4, the semiconductor module cooler 1 has a configuration (see FIG. 3A) in which aluminum plates 3 and 3 are arranged on both upper and lower surfaces of a PPS resin molded product 2, and a pair of stacked semiconductor modules. Between the coolers 1 and 1, spaces (module placement portions 7) for placing the semiconductor modules 10, 10... Are formed. Then, by disposing the semiconductor module 10 in the module disposition portion 7, it becomes possible to efficiently exhaust heat from the semiconductor modules 10, 10.

  That is, as shown in FIG. 4, the semiconductor module cooler 1 shown in FIGS. 3 (a) and 3 (b) can form a series of cooling water channels 5 by laminating a plurality and combining them in a header shape. A plurality of semiconductor modules 10, 10... Can be configured as a semiconductor module cooler group capable of efficiently cooling at a time while realizing space saving.

Next, the confirmation result of the peel strength between the PPS resin molded product 2 and the aluminum plate 3 will be described with reference to FIG.
The peel strength measurement results shown in FIG. 5 (a) are obtained when the PPS material and the aluminum plate as shown in FIG. 5 (b) are directly laminated (that is, there is no elastic body 4) and through the elastic body 4. The adhesive strength (peeling strength) was measured based on JISK6829 using two types of test pieces in the case of being laminated (that is, having the elastic body 4).
The PPS material and the aluminum plate used for the test piece have a common size of 25 mm in width and 100 mm in length, and are obtained by injection welding in a state where both materials are wrapped 12.5 mm in the length direction. .

According to FIG. 5A, the peel strength when the elastic body 4 is present is approximately 11.2 MPa, and the peel strength when the elastic body 4 is absent is approximately 0.4 MPa. The peel strength when present is about 28 times that when there is no peel strength.
A semiconductor module cooler 1 according to an embodiment of the present invention has a configuration in which an elastic body 4 is interposed between a PPS resin molded product 2 and an aluminum plate 3, and is bonded to a PPS resin molded product as compared with the conventional one. 2 and the aluminum plate 3 can be greatly improved in peel strength. From the above measurement results, it was confirmed that such an improvement effect was obtained.

Moreover, the state of the welding surface of a PPS material and an aluminum plate was confirmed besides the measurement of peeling strength.
The state of the welded surface between the PPS material and the aluminum plate was confirmed by ultrasonic inspection.
According to the results of the ultrasonic flaw detection, it was confirmed that when there was no elastic body 4, a void was formed on the weld surface, but when there was an elastic body 4, there was a void on the weld surface. Was not recognized. If there is a void in the weld surface, it is considered that the peel strength is reduced due to the reduction in the bonding area. However, when the elastic body 4 is provided, the reduction in the bonding area does not occur. Will be certain.
That is, the effectiveness of joining the PPS resin molded product 2 and the aluminum plate 3 via the elastic body 4 was confirmed also from the confirmation result by the ultrasonic flaw detection.

That is, the semiconductor module cooler 1 according to an embodiment of the present invention includes a PPS resin molded product 2 in which a groove 2a is formed and an aluminum plate 3 that covers the groove 2a, and is cooled by the groove 2a and the aluminum plate 3. A water channel 5 is formed to cool the semiconductor module 10 in contact with the aluminum plate 3 by a cooling medium flowing through the cooling water channel 5, and the PPS resin molded product 2 and the aluminum plate 3 are joined via the elastic body 4. To do.
With such a configuration, the peel strength of the aluminum plate 3 with respect to the PPS resin molded product 2 can be increased as compared with the case where the PPS resin molded product 2 and the aluminum plate 3 are directly joined.

DESCRIPTION OF SYMBOLS 1 Semiconductor module cooler 2 PPS resin molded product 2a Groove part 3 Aluminum plate 4 Elastic body 5 Cooling water channel 10 Semiconductor module

Claims (1)

A PPS resin molded product in which a groove is formed, and an aluminum plate that covers the groove,
A cooling water channel is formed by the groove and the aluminum plate,
A semiconductor module cooler that cools the semiconductor module in contact with the aluminum plate by a cooling medium flowing through the cooling water channel,
The PPS resin molded product and the aluminum plate,
Joining via elastic body,
A semiconductor module cooler characterized by that.

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