Semiconductor Devices

Abstract

This semiconductor device includes a power module, a first casing and a second casing having bonding surfaces thereof bonded to each other to form a refrigerant flow path, and a sealant, wherein a sealant coating portion to which the sealant is applied is provided at the bonding surface of the first casing or the second casing, a sealant pressing portion that applies pressure to the sealant is provided at a position corresponding to the sealant coating portion at the other bonding surface, and a sealant inflow suppressing portion that suppresses the inflow of the sealant to the refrigerant flow path is provided at a position closer to the refrigerant flow path than the sealant coating portion at the bonding surface of either the first casing or the second casing.

Description

[Technical Field]

[0001] The present invention relates to a semiconductor device. [Background technology]

[0002] A cooling flow path for cooling a semiconductor device is formed by joining two housings together, and high reliability is required for assembling the housings together when forming the cooling flow path.

[0003] For example, Patent Document 1 listed below discloses a power converter having a double-grooved structure and a protrusion on the surface where the sealing material is applied at the joint between the housings. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-92209 Summary of the Invention [Problem to be solved by the invention]

[0005] Although the structure of Patent Document 1 does not pose a problem with the sealing itself, there is a possibility that the sealant may come into contact with the coolant flow path, resulting in corrosion and deterioration of assembly. In view of this, an object of the present invention is to provide a semiconductor device that prevents a decrease in adhesive strength and prevents the adhesive from flowing into the coolant flow path. [Means for solving the problem]

[0006] The semiconductor device includes a power module that uses a semiconductor to output power to drive a motor, a first housing and a second housing that each have adhesive surfaces and that form a refrigerant flow path that cools the power module by adhering the adhesive surfaces to each other, and a sealant that seals the adhesive surfaces between the first housing and the second housing, wherein the adhesive surface of either the first housing or the second housing has a sealant application portion to which the sealant is applied, and the other adhesive surface has a sealant pressing portion that presses the sealant at a position corresponding to the sealant application portion, and the adhesive surface of either the first housing or the second housing has a sealant inflow suppression portion that suppresses the inflow of the sealant into the refrigerant flow path at a position closer to the refrigerant flow path than the sealant application portion. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a semiconductor device that can prevent a decrease in adhesive strength and prevent the adhesive from flowing into the coolant flow path. [Brief explanation of the drawings]

[0008] [Figure 1] Exploded perspective view of a power conversion device [Figure 2] 2 is a cross-sectional view of the power converter of FIG. 1 taken along line AA according to one embodiment of the present invention; [Figure 3] 3 is an explanatory diagram of the adhesive portion between the housings of FIG. 2 according to one embodiment of the present invention; [Figure 4] 1 is an explanatory diagram illustrating the relationship between a sealing material and an adhesive surface according to an embodiment of the present invention. [Figure 5] Shape pattern of the pressing part and application part [Figure 6] First to fourth modified examples of the pressing portion, the application portion, and the reservoir portion [Figure 7] Fifth and Sixth Modifications of the Pressing Section, the Application Section, and the Reservoir Section

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and some omissions and simplifications have been made as appropriate for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0010] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0011] (One embodiment of the present invention and overall configuration of the device) (Figure 1) Fig. 1(a) is an explanatory diagram of the power module housed in the housing, and Fig. 1(b) is an explanatory diagram of the lower cover attached to the housing. In the semiconductor device 1, a power module 3 that uses semiconductors to output power to drive a motor is inserted into a case 5, and a power module plate 13 is assembled to the case 5 to house and hold the power module 3 in a sandwiched manner.

[0012] The lower cover 4 has a water channel pipe 14. The water channel pipe 14 is press-fitted into the lower cover 4. A sealant (described later) is applied to the groove of the case 5, and the lower cover 4 is assembled to the case 5 so that the sealant is sandwiched between them.

[0013] (Figure 2) Fig. 2(a) is a cross-sectional view taken along line AA in Fig. 1(b), and Fig. 2(b) is an enlarged view of the housing connection portion in Fig. 2(a). The semiconductor device 1 has a power module 3, and a lower cover 4 is attached to the case 5 to house the power module 3 inside the case 5. This forms a refrigerant flow path 2 that cools the power module 3. In the following explanation, the lower cover 4 will be referred to as the first housing 4, and the case 5 will be referred to as the second housing 5.

[0014] At the housing connection portion 6, when the first housing 4 and the second housing 5 are bonded to each other at their respective bonding surfaces to form the refrigerant flow path 2, a sealant 7 is used on the bonding surfaces. The sealant 7 is, for example, a silicone-based adhesive, and bonds and seals the bonding surfaces of the first housing 4 and the second housing 5. At the housing connection portion 6, when the first housing 4 and the second housing 5 are connected, two grooves are formed in the connection portion: a groove formed by the sealant pressing portion 9 and the sealant application portion 10, and a groove formed by the sealant inflow suppression portion 8. Of these two grooves, the groove located on the outer periphery of the first housing 4 and the second housing 5 is the sealant pressing portion 9 on the first housing 4 and the sealant application portion 10 on the second housing 5.

[0015] The sealant application portion 10 has a recessed shape, and the sealant pressing portion 9 has a protruding shape with a protrusion. The sealant application portion 10 and the sealant pressing portion 9 are bonded together so as to surround the refrigerant flow path 2. The sealant application portion 10 may have a trapezoidal shape in consideration of the ease of flow of the sealant 7.

[0016] On the other hand, the second housing 5 has a recessed sealant inflow suppression portion 8 as a groove formed on the adhesive surface of either the first housing 4 or the second housing 5 at a position closer to the refrigerant flow path 2 than the sealant application portion 10. The sealant inflow suppression portion 8 is formed so as to surround the refrigerant flow path 2. In addition, a sealant reservoir 12 is provided outside the refrigerant flow path 2 of the first housing 4 and the second housing 5.

[0017] 2, the sealant application section 10 may be formed on the adhesive surface of either the first housing 4 or the second housing 5, and the sealant 7 may be applied thereto. In this case, the sealant pressing section 9 is formed on the other adhesive surface, and presses the sealant 7 placed on the sealant application section 10 at a position corresponding to the sealant application section 10.

[0018] (Figure 3) The sealant applicator 10 and the sealant inflow suppressor 8 are positioned to control the spread of the sealant 7 when the first housing 4 and the second housing 5 are bonded together. The sealant applicator 10 is positioned on the bonding surface between the first housing 4 and the second housing 5, closer to the outer periphery than the refrigerant flow path 2. On the other hand, the sealant inflow suppressor 8 is positioned on the bonding surface between the first housing 4 and the second housing 5, closer to the refrigerant flow path 2 than the outer periphery.

[0019] If we define the length from the sealant application portion 10 to the sealant inflow suppression portion 8 on the bonding surface as a first length 11a and the length from the outer periphery of the bonding surface to the sealant application portion 10 as a second length 11b, the first length 11a is longer than the second length 11b. In other words, the bonding area is wider near the refrigerant flow path 2 than near the outer periphery of the bonding surface, based on the sealant application portion 10. This is because the refrigerant in the refrigerant flow path 2 applies internal pressure to the bonding surface, causing the first housing 4 to expand due to the internal pressure. To efficiently transfer the load due to the internal pressure to the sealant 7, the portion with the larger bonding area (first length 11a) is positioned closer to the refrigerant flow path 2. Furthermore, since the sealant 7 overflows into the sealant inflow suppression portion 8 when the housings are bonded together, a wide bonding surface is provided along the first length 11a to prevent the sealant 7 from overflowing.

[0020] (Figure 4) Fig. 4(a) is a diagram showing the sealant 7 applied to the sealant application section 10, Fig. 4(b) is a diagram showing the state in the middle of bonding the first housing 4 and the second housing 5, and Fig. 4(c) is a diagram showing the state when the first housing 4 and the second housing 5 have been bonded. Figs. 4(a) to 4(c) show a series of processes for connecting the housings.

[0021] First, sealant 7 is applied to sealant application section 10 of second housing 5. The amount of sealant 7 applied is controlled to a predetermined amount by an applicator or the like, and is adjusted so that the sealant 7, which is pushed out in the left-right direction when the housings are bonded, can be retained in sealant inflow suppression section 8, thereby suppressing the inflow of sealant 7 into refrigerant flow path 2. In addition, the width of sealant application section 10 is set to a width that can adequately receive the amount of sealant 7 applied.

[0022] Next, in the process of attaching the first housing 4 to the second housing 5, the sealant pressing portion 9 of the first housing 4 comes into contact with the sealant 7 applied to the sealant application portion 10 and begins to press the sealant 7. When the first housing 4 and the second housing 5 are bonded together, the sealant pressing portion 9 bites into the sealant 7, crushing and spreading it. The adhesive areas of the concave sealant application portion 10 and the convex sealant pressing portion 9 are equal and are arranged so that there is no difference in adhesiveness, so that the sealant 7 does not peel off at the interface and has sufficient adhesive strength.

[0023] When the first housing 4 is assembled to the second housing 5, the sealing material 7 is spread out in the left-right direction of the adhesive surface. As a result, part of the sealing material 7 accumulates in the groove of the sealing material inflow suppression portion 8 on the refrigerant flow path 2 side, while part of the sealing material 7 accumulates in the sealing material reservoir portion 12 as it spreads out toward the outer periphery.

[0024] Since the bonding process between the housings is carried out using this configuration, the sealant pressing section 9 of the first housing 4 separates the air entrained in the sealant 7 and expels it toward both ends of the bonding surface, ensuring a sufficient bonding area at the sealant application section 10. Furthermore, by making the adhesive strength uniform, the adhesive force of the bonding surface is stabilized. Furthermore, since the application and pressing of the sealant 7 is carried out using only one groove, rather than the double groove structure shown in the prior art, air entrainment is prevented, thereby improving the reliability of the bond.

[0025] At the bonding surface between the housings, the end of the first housing 4 on the refrigerant flow path 2 side is defined as the first end 4a, the end of the first housing 4 on the outer periphery side is defined as the second end 4b, the end of the second housing 5 on the refrigerant flow path 2 side is defined as the third end 5a, and the end of the second housing 5 on the outer periphery side is defined as the fourth end 5b. The first housing 4 and the second housing 5 are bonded together so that the first end 4a and the third end 5a contact each other and the second end 4b and the fourth end 5b contact each other.

[0026] Since the sealing material 7 has a tendency to adhere to the housing with the larger surface area when the housings are overlapped, which can cause problems with the reliability of the adhesive surface, this problem can be prevented by adhering the first housing 4 and the second housing 5 so that the lengths between their ends match. Furthermore, by aligning the first end 4a and the third end 5a, the sealing material 7 has the effect of not flowing into the refrigerant flow path 2 even if it separates from the sealing material inflow suppression portion 8.

[0027] Furthermore, the first housing 4 and the second housing 5 are provided with a sealant reservoir 12 for storing the sealant 7 on the outer periphery of the adhesive surface of each housing. This prevents the sealant 7 from overflowing onto the outer periphery of the adhesive surface, and prevents salt accumulation in the overflowed portion, thereby suppressing corrosion of the sealant 7.

[0028] (Figure 5) The sealant applicator 10 has sloped edges rather than right angles so that when the sealant 7 is applied and the first housing 4 is attached to the second housing 5, the sealant pressing section 9 can push out the sealant 7 and expel air. This makes it easier for the sealant 7 to flow when the housings are bonded together. The sealant pressing section 9 is the center of the left and right spread of the sealant 7 during assembly, so the way the sealant 7 spreads can be controlled by the position and shape of the pressing section 9.

[0029] At least one of the sealant pressing portion 9 and the sealant applying portion 10 of the first housing 4 may be trapezoidal. Fig. 5(a) shows an example in which the sealant pressing portion 9 is trapezoidal. In Fig. 5(a), the sealant pressing portion 9 and the sealant applying portion 10 are positioned symmetrically with respect to the center line 16.

[0030] The shape of the sealing material pressing portion 9 may be symmetrical or asymmetrical. Specifically, as shown in Fig. 5(b), the position of the sealing material pressing portion 9 relative to the width of the sealant-applied portion 10 may be such that a groove length 15a from the sealing material pressing portion 9 to one end of the sealant-applied portion 10 is different from a groove length 15b from the sealing material pressing portion 9 to the other end of the sealant-applied portion 10. Furthermore, as shown in Fig. 5(c), the sealing material pressing portion 9 may be a sealing material pressing portion 9a that is asymmetrical with respect to the center line 16.

[0031] Although an example of a trapezoidal pattern for the sealing material pressing portion 9 has been shown above, other shapes may be used as long as they can press the sealing material 7 and ensure adhesive reliability at the adhesive surfaces between the housings.

[0032] (First to fourth modified examples) (Figure 6) The sealant inflow suppression unit 8 may be provided in either the first housing 4 or the second housing 5. Furthermore, the sealant pressing unit 9 and the sealant application unit 10 can be arranged regardless of whether the sealant inflow suppression unit 8 is attached to the first housing 4 or the second housing 5, as long as the sealant pressing unit 9 is housed in the sealant application unit 10 during bonding.

[0033] FIG. 6(a) shows an example in which the sealant inflow suppression unit 8 and the sealant application unit 10 are arranged in the second housing 5, and the sealant pressing unit 9 is arranged in the first housing 4. FIG. 6(b) shows an example in which the sealant inflow suppression unit 8 and the sealant pressing unit 9 are arranged in the first housing 4, and the sealant application unit 10 is arranged in the second housing 5. FIG. 6(c) shows an example in which the sealant inflow suppression unit 8 and the sealant application unit 10 are arranged in the first housing 4, and the sealant pressing unit 9 is arranged in the second housing 5. FIG. 6(d) shows an example in which the sealant application unit 10 is arranged in the first housing 4, and the sealant inflow suppression unit 8 and the sealant pressing unit 9 are arranged in the second housing 5.

[0034] (Fifth Modification, Sixth Modification) (Figure 7) As shown in Figure 7(a), a sealant pressing portion 9b having a groove around the pressing portion can also achieve the same effect, and this allows the sealant pressing portion 9 to be formed with simpler processing than a sealant pressing portion 9 without a groove. Also, as shown in Figure 7(b), the sealant application portion 10 does not need to have an adhesive area corresponding to the sealant pressing portion 9, and the sealant pressing portion 9 may not be positioned at the center of the sealant application portion 10.

[0035] According to the embodiment of the present invention described above, the following advantageous effects are achieved.

[0036] (1) The semiconductor device 1 includes a power module 3 that uses a semiconductor to output power to drive a motor, a first housing 4 and a second housing 5 each having an adhesive surface that is bonded to each other to form a refrigerant flow path 2 that cools the power module 3, and a sealant 7 that seals the adhesive surfaces between the first housing 4 and the second housing 5. The adhesive surface of either the first housing 4 or the second housing 5 has a sealant application section 10 to which the sealant 7 is applied, and the other adhesive surface has a sealant pressing section 9 that presses the sealant 7 at a position corresponding to the sealant application section 10, and the adhesive surface of either the first housing 4 or the second housing 5 has a sealant inflow suppression section 8 that suppresses the inflow of the sealant 7 into the refrigerant flow path 2, at a position closer to the sealant application section 10. This configuration makes it possible to provide a semiconductor device 1 that both prevents a decrease in adhesive strength and prevents adhesive from inflow into the refrigerant flow path.

[0037] (2) The sealant application portion 10 has a concave shape, and the sealant pressing portion 9 has a convex shape, and the sealant application portion 10 and the sealant pressing portion 9 are bonded together so as to surround the refrigerant flow path 2. In this way, the refrigerant flow path 2 is formed by the housing with a stable bonding surface.

[0038] (3) At least one of the sealant application portion 10 and the sealant pressing portion 9 has a trapezoidal shape, which makes it easier for the sealant 7 to flow.

[0039] (4) The sealing material inflow suppression portion 8 is recessed and is formed to surround the refrigerant flow path 2. This ensures the reliability of the adhesive surface while controlling the spreading of the sealing material 7 so that the sealing material 7 does not flow into the refrigerant flow path 2.

[0040] (5) At the bonding surface, the length from the position of the sealant application portion 10 to the position of the sealant inflow suppression portion 8 is longer than the length from the outer periphery of the bonding surface to the position of the sealant application portion 10. This allows the load due to the internal pressure from the refrigerant flow path 2 to be efficiently transmitted to the sealant 7.

[0041] (6) The bonding surface of the first housing 4 has a first end 4a which is the end on the refrigerant flow path 2 side and a second end 4b which is the end on the outer periphery side, and the bonding surface of the second housing 5 has a third end 5a which is the end on the refrigerant flow path 2 side and a fourth end 5b which is the end on the outer periphery side, and the first housing 4 and the second housing 5 are bonded so that the first end 4a and the third end 5a are in contact and the second end 4b and the fourth end 5b are in contact. This prevents the sealant 7 from entering the refrigerant flow path 2.

[0042] (7) The first housing 4 and the second housing 5 each have a sealant reservoir 12 for storing the sealant 7 at the outer periphery of the adhesive surface of the housing. This prevents salt from pooling in the protruding portion, thereby suppressing corrosion of the sealant 7.

[0043] The present invention is not limited to the above-described embodiments, and various modifications and combinations of other configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to those having all of the configurations described in the above-described embodiments, and includes those in which some of the configurations are omitted. [Explanation of symbols]

[0044] 1. Semiconductor device 2 Coolant flow path 3 Power Module 4 Lower cover (first housing) 4a 1st end 4b Second end 5 Case (secondary enclosure) 5a 3rd end 5b 4th end 6 Housing connection 7 Sealing material 8 Sealing material inflow prevention section 9 Sealing material pressing part 9a Asymmetrical pressing part 9b Pressing portion with grooves around the periphery 10 Sealant application section 10a Application part with large grooves 11 Length 11a First Length 11b Second Length 12 Sealing material storage section 13 Power module plate 14 Waterway Pipe 15 Length 15a Length of first groove 15b Second groove length 16 Center line

Claims

1. a power module that uses semiconductors to output power to drive a motor; a first housing and a second housing each having a bonding surface, the bonding surfaces being bonded to each other to form a refrigerant flow path for cooling the power module; a sealing material that seals the adhesive surfaces between the first housing and the second housing, a sealant application section to which the sealant is applied is provided on the adhesive surface of either the first housing or the second housing; a sealant pressing portion for pressing the sealant at a position corresponding to the sealant application portion on the other adhesive surface; a sealant inflow suppression portion that suppresses inflow of the sealant into the refrigerant flow path, the sealant inflow suppression portion being located on the adhesive surface of either the first housing or the second housing closer to the refrigerant flow path than the sealant application portion; On the adhesive surface, a length from a position of the sealant application portion to a position of the sealant inflow suppression portion is greater than a length from an outer periphery of the adhesive surface to a position of the sealant application portion. Semiconductor device.

2. 2. The semiconductor device according to claim 1, the sealant application portion has a recessed shape, the sealing material pressing portion has a convex shape, The sealant application portion and the sealant pressing portion are bonded together so as to surround the refrigerant flow path. Semiconductor device.

3. 2. The semiconductor device according to claim 1, At least one of the sealant application portion and the sealant pressing portion has a trapezoidal shape. Semiconductor device.

4. 2. The semiconductor device according to claim 1, The sealing material inflow suppression portion has a recessed shape and is formed so as to surround the refrigerant flow path. Semiconductor device.

5. 2. The semiconductor device according to claim 1, the adhesive surface of the first housing has a first end portion that is an end portion on the coolant flow path side and a second end portion that is an end portion on the outer periphery side, the adhesive surface of the second housing has a third end portion which is an end portion on the coolant flow path side and a fourth end portion which is an end portion on the outer periphery side, The first housing and the second housing are bonded together such that the first end and the third end are in contact with each other and the second end and the fourth end are in contact with each other. Semiconductor device.

6. The semiconductor device according to any one of claims 1 to 5, The first housing and the second housing each have a sealant reservoir portion for storing the sealant at the outer periphery of the adhesive surface of the housing. Semiconductor device.

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