Semiconductor module and semiconductor device

Abstract

A cooler (30): has a heat dissipation base (31) and a plurality of heat dissipation fins (32) that are positioned on the opposite side of the heat dissipation base (31) from a substrate (20); and is attached to a water jacket (110) that is for making cooling water (W) flow through the heat dissipation fins (32). An insulation material (40) integrates: a bottom part (41) that extends in the direction (D) in which the cooling water (W) flows through the heat dissipation fins (32) and is opposite at least a portion of the heat dissipation fins (32); and a side wall (42) that extends from the bottom part (41) toward the heat dissipation base (31) side and is opposite at least a portion of the heat dissipation fins (32).

Description

Semiconductor module and semiconductor device

[0001] The present invention relates to a semiconductor module including a cooler, and a semiconductor device including this semiconductor module and a water jacket.

[0002] Among semiconductor devices used in power conversion devices such as inverters, there are known semiconductor devices in which cooling water flows through multiple heat dissipation fins in a water jacket to cool semiconductor elements by heat dissipation (see, for example, Patent Documents 1 to 4). A clearance is provided between the multiple heat dissipation fins and the water jacket to prevent them from contacting each other due to dimensional variations during manufacturing.

[0003] Japanese Patent No. 7160216 International Publication No. 2012 / 114475 International Publication No. 2014 / 045758 Japanese Patent Application Laid-Open No. 2007-110025

[0004] The larger the clearance between the multiple heat dissipation fins and the water jacket, the less cooling water passes through the gaps between the fins, resulting in a deterioration in cooling performance. Furthermore, in the clearance, a local battery is formed due to a potential difference, generating corrosion products. These corrosion products can also clog the gaps between the fins, resulting in a deterioration in cooling performance. However, fixing and positioning components that block the clearance increases the time and effort required to assemble the semiconductor device.

[0005] An object of the present invention is to provide a semiconductor module and a semiconductor device that can be easily assembled while improving cooling performance and preventing corrosion.

[0006] In one aspect, a semiconductor module includes a semiconductor device, a substrate, a cooler, and an insulating material. The semiconductor device is mounted on the substrate. The cooler has a heat dissipation base and a plurality of heat dissipation fins located on the opposite side of the heat dissipation base from the substrate, and is attached to a water jacket for flowing cooling water through the plurality of heat dissipation fins. The insulating material integrally includes a bottom portion extending in the direction of flow of the cooling water through the plurality of heat dissipation fins and facing at least a portion of the tips of the plurality of heat dissipation fins, and a sidewall extending from the bottom portion toward the heat dissipation base and facing at least a portion of the plurality of heat dissipation fins.

[0007] According to the above aspect, in the semiconductor module and the semiconductor device, the assembly can be facilitated while improving the cooling performance and preventing corrosion.

[0008] 13A and 13B are cross-sectional views of a semiconductor device according to an embodiment, illustrating the internal structure of a water jacket; a right side view of a semiconductor device according to an embodiment, illustrating the internal structure of a water jacket; an exploded perspective view of a cooler, an insulator, and a water jacket according to an embodiment; a front view of a semiconductor device according to an embodiment, illustrating the internal structure of a water jacket; a cross-sectional view taken along line IV-IV of FIG. 3; a cross-sectional view taken along line IV-IV of FIG. 3 of a first modified example of an embodiment; a graph illustrating the relationship between the installation size of an insulator and pressure loss; a cross-sectional view taken along line IV-IV of FIG. 3 of a second modified example of an embodiment; a cross-sectional view taken along line IV-IV of FIG. 3 of a third modified example of an embodiment; a cross-sectional view taken along line IV-IV of FIG. 3 of a fourth modified example of an embodiment; a right side view of a semiconductor device according to a fifth modified example of an embodiment, illustrating the internal structure of a water jacket; a cross-sectional view taken along line IV-IV of FIG. 3 of a fifth modified example of an embodiment; a right side view of a semiconductor device according to a sixth modified example of an embodiment, illustrating the internal structure of a water jacket according to an embodiment; a right side view of a semiconductor device according to an embodiment, illustrating the internal structure of a water jacket with the insulator removed; a front view of a semiconductor device according to an embodiment, illustrating the internal structure of a water jacket with the insulator removed; a cross-sectional view taken along line XIV-XIV of FIG. 13; an explanatory view for explaining the generation of corrosion products. FIG. 10 is a front view of the semiconductor device showing the internal structure of the water jacket for explaining the corroded portion with the insulating material removed.

[0009] A semiconductor module and a semiconductor device according to an embodiment of the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the embodiment described below, and can be modified as appropriate within the scope of the present invention.

[0010] FIG. 1 is a right side view of a semiconductor device 100 showing the internal structure of a water jacket 110 according to one embodiment.

[0011] FIG. 2 is an exploded perspective view of the cooler 30, the insulating material 40, and the water jacket 110.

[0012] FIG. 3 is a front view of the semiconductor device 100 showing the internal structure of the water jacket 110.

[0013] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.

[0014] 1 to 4 and FIGS. 5A, 6 to 14, and 16, which will be described later, the thickness direction of the semiconductor element 10 is defined as the Z direction, and of the X and Y directions that are perpendicular to the Z direction and perpendicular to each other, the flow direction D of the cooling water W is defined as the positive X direction. In some cases, the X direction may be referred to as the left-right direction, the Y direction as the front-back direction, and the Z direction as the up-down direction. These directions are terms used for convenience of explanation, and the corresponding relationships between the X direction, Y direction, and Z direction will change depending on the mounting orientation of the semiconductor device 100.

[0015] The semiconductor module 1 according to this embodiment is a power semiconductor module that is applied to a power conversion device such as a power control unit, and constitutes an inverter circuit. The semiconductor module 1 and the semiconductor device 100 that includes the semiconductor module 1 and the water jacket 110 can be used for any purpose, but may be used, for example, as an inverter device for an in-vehicle or industrial motor.

[0016] 1 and 3 includes a semiconductor module 1 and a water jacket 110. The semiconductor module 1 includes two semiconductor elements 10, a laminated substrate 20, a cooler 30, and an insulating material 40.

[0017] The water jacket 110 is attached to the lower part of the cooler 30 by, for example, fastening screws. The water jacket 110 is provided, for example, in an inverter case of an inverter device. In order to ensure watertightness inside the water jacket 110, it is preferable to place a sealant such as an O-ring between the upper surface of the water jacket 110 and the cooler 30 (heat dissipation base 31).

[0018] The water jacket 110 is made of a die-cast material such as aluminum alloy (ADC12). The water jacket 110 has a rectangular parallelepiped shape with an opening at the top, and coolant W flows through the interior, which houses a plurality of heat dissipation fins 32. The coolant W flows in a flow direction D to the right (positive side of the X direction) so as to pass through the plurality of heat dissipation fins 32 of the cooler 30, and heat is transferred from the plurality of heat dissipation fins 32. The coolant W is a liquid such as water containing additives such as antifreeze, anti-rust agents, and antioxidants.

[0019] The bottom surface 111 of the interior of the water jacket 110, through which the cooling water W flows, faces the tips 32a of the multiple heat dissipation fins 32, with the insulating material 40 interposed therebetween. The front and rear side surfaces 112, 113 of the interior of the water jacket 110 extend in the XZ plane, and therefore extend along a flow direction D (positive side of the X direction) in which the cooling water W flows through the multiple heat dissipation fins 32. In this embodiment, the flow direction D is parallel to the longitudinal direction (X direction) of the area in which the multiple heat dissipation fins 32 are arranged in a plan view (see FIG. 4), but may also be parallel to the lateral direction (Y direction).

[0020] 2 and 3 , an inlet pipe 114 for introducing cooling water W into the water jacket 110 and an outlet pipe 115 for discharging the cooling water W from the water jacket 110 are connected to the bottom surface 111 of the water jacket 110. The inlet pipe 114 and the outlet pipe 115 extend downward (toward the negative side in the Z direction) from the bottom surface 111. However, the inlet pipe 114 and the outlet pipe 115 may extend in the X direction or the Y direction.

[0021] The two semiconductor elements 10 of the semiconductor module 1 are mounted on a laminated substrate 20 (circuit board 22) by a bonding material S1, such as solder, and are connected to other circuit boards by conductor wires, metal wiring boards, etc. The semiconductor elements 10 are formed into a square or rectangular shape in plan view using a semiconductor substrate made of, for example, silicon (Si), silicon carbide (SiC), gallium nitride (GaN), diamond, or the like.

[0022] The semiconductor element 10 may be a switching element such as an insulated gate bipolar transistor (IGBT) or a power metal oxide semiconductor field effect transistor (MOSFET), or a diode such as a free wheeling diode (FWD). The switching element and the diode may be connected in anti-parallel. Alternatively, the semiconductor element 10 may be a reverse conducting (RC) IGBT element in which an IGBT and an FWD are integrated, a power MOSFET element, or a reverse blocking (RB) IGBT element having sufficient withstand voltage against reverse bias.

[0023] The laminated substrate 20 is an example of a substrate on which the semiconductor element 10 is mounted. The laminated substrate 20 is formed, for example, of a DCB (Direct Copper Bonding) substrate, an AMB (Active Metal Brazing) substrate, or a metal-based substrate. The laminated substrate 20 is formed, for example, in a rectangular shape when viewed from above. The laminated substrate 20 includes an insulating plate 21, a circuit board 22, and a heat sink 23.

[0024] The insulating plate 21 is made of, for example, aluminum oxide (Al ２ O ３ ), aluminum nitride (AlN), silicon nitride (Si ３ N ４ ), aluminum oxide and zirconium oxide (ZrO ２ The insulating plate 21 is formed of an insulating material such as a ceramic material, a composite material with a ceramic material, a resin material such as epoxy, or an epoxy resin material using a ceramic material as a filler. The insulating plate 21 may also be called an insulating layer or an insulating film.

[0025] The circuit board 22 is formed on the upper surface of the insulating plate 21. The number of circuit boards 22 may be any number equal to or greater than one. The circuit board 22 is a metal layer such as copper foil, and, for example, a plurality of circuit boards 22 are formed in the shape of islands on the insulating plate 21 while being electrically insulated from one another. The circuit board 22 may also be called a circuit pattern, a circuit layer, a wiring board, a wiring pattern, a wiring layer, etc.

[0026] The heat sink 23 is formed on the lower surface of the insulating plate 21. The heat sink 23 is preferably formed from a metal plate with good thermal conductivity, such as copper or aluminum. The heat sink 23 is joined to the upper surface 31a of the heat sink base 31 of the cooler 30 by a joining material S2, such as solder. The heat sink 23 may also be called a heat sink layer.

[0027] The two semiconductor elements 10 and the laminated substrate 20 are arranged on the heat dissipation base 31. However, these two semiconductor elements 10 and the laminated substrate 20 may be used as one set of semiconductor units, and three sets of semiconductor units forming a three-phase inverter circuit may be arranged. In this way, the number of semiconductor elements 10 and the laminated substrate 20 is not particularly limited.

[0028] A rectangular frame-shaped resin case is placed on top of the heat dissipation base 31 so as to surround the two semiconductor elements 10 and the laminated substrate 20, and this case is filled with a sealing material (e.g., resin or gel) so as to cover the two semiconductor elements 10 and the laminated substrate 20. The sealing material may be formed by transfer molding or potting.

[0029] The cooler 30 includes a heat dissipation base 31 and a plurality of heat dissipation fins 32. The cooler 30 is made of, for example, copper or aluminum.

[0030] The heat dissipation base 31 has, for example, a rectangular plate shape. The laminated substrate 20 (heat dissipation plate 23) is bonded to the upper surface 31a, which is an example of a first surface of the heat dissipation base 31, by the bonding material S2 as described above. The heat dissipation base 31 can be called the top plate of the cooler 30. Note that the laminated substrate 20 may be bonded to the upper surface 31a of the heat dissipation base 31 via, for example, a heat dissipation plate or the like.

[0031] The plurality of heat dissipation fins 32 protrude from a lower surface 31b, which is an example of a second surface of the heat dissipation base 31. As a result, the plurality of heat dissipation fins 32 are located on the opposite side of the heat dissipation base 31 from the laminated substrate 20 (negative side in the Z direction). The heat dissipation fins 32 can be considered open fins exposed to the outside of the cooler 30 below the heat dissipation base 31. The plurality of heat dissipation fins 32 may be formed integrally with the heat dissipation base 31 or may be formed by being fixed to the heat dissipation base 31. The plurality of heat dissipation fins 32 are, for example, pin fins and have a cylindrical shape as shown in FIG. 4 . The plurality of heat dissipation fins 32 are arranged in multiples in both the X and Y directions. The heat exchange performance of the plurality of heat dissipation fins 32 increases as the flow rate of the cooling water W passing through the heat dissipation fins 32 increases. Therefore, the density and arrangement of the heat dissipation fins 32 are designed taking into account the balance with the allowable pressure of the pump circulating the cooling water W.

[0032] The multiple heat dissipation fins 32 are not limited to cylindrical pin fins, but may also be pin fins of other shapes such as polygonal pillars, flat fins (plate fins), curved plate fins (corrugated fins), etc., and are not particularly limited.

[0033] The insulating material 40 has a bottom (bottom wall) 41 and opposing side walls 42, 43, and is generally U-shaped (or U-shaped) when viewed from the right side (see FIG. 1 ). The insulating material 40 may be made of an elastic material such as silicone rubber or ethylene propylene rubber. When the insulating material 40 is made of an elastic material, assembly is particularly easy. For example, the insulating material 40 may be attached to the cooler 30 and then the semiconductor module 1 may be mounted in the water jacket 110, or the insulating material 40 may be placed in the water jacket 110 and then the cooler 30 may be mounted on the insulating material 40. The insulating material 40 may be disposed by applying a liquid paste or the like to the water jacket 110. The insulating material 40 may also be fixed to the cooler 30 or the water jacket 110 by adhesive or the like.

[0034] As shown in Fig. 1, the bottom portion 41 of the insulating material 40 is disposed on at least a portion of the bottom surface 111 inside the water jacket 110 and has a flat plate shape. The bottom portion 41 extends along the flow direction D in which the cooling water W flows through the plurality of heat dissipation fins 32, and is disposed so as to face at least a portion of the tips 32a of the plurality of heat dissipation fins 32. As shown in Fig. 4, the bottom portion 41 is preferably disposed on the bottom surface 111 of the water jacket 110 so as to face the tips 32a of all the heat dissipation fins 32. In other words, the bottom portion 41 is preferably formed to be equal to or larger than the area in which the plurality of heat dissipation fins 32 are disposed in both the X and Y directions.

[0035] The bottom 41 is preferably made of an elastic material as described above to prevent the heat dissipation fins 32 (cooler 30) from being pressed upward by the bottom 41 when the heat dissipation fins 32 expand downward (negative side in the Z direction) due to thermal expansion, thereby preventing the airtightness between the cooler 30 and the water jacket 110 from being impaired or the heat dissipation fins 32 from being deformed. Note that thermal expansion can cause not only expansion of the heat dissipation fins 32 in the negative Z direction, but also expansion of the heat dissipation fins 32 in the X and Y directions and expansion of the water jacket 110 toward the heat dissipation fins 32. Therefore, it is preferable that the entire insulating material 40 be made of an elastic material as described above so as to be able to follow the thermal deformation of the heat dissipation fins 32 and the water jacket 110.

[0036] The sidewall 42 (first sidewall) is disposed on at least a portion of the side surface 112, which is the front surface of the interior of the water jacket 110, and is flat. The sidewall 43 (second sidewall) is disposed on at least a portion of the side surface 113, which is the rear surface of the interior of the water jacket 110, and is flat. The sidewalls 42, 43 extend from the bottom 41 toward the heat dissipation base (positive side in the Z direction) and are positioned to face at least a portion of the heat dissipation fins. As shown in FIG. 4 , the sidewalls 42, 43 are preferably formed to be equal to or larger than the area in the X direction in which the multiple heat dissipation fins 32 are arranged. As shown in FIG. 3 , the sidewalls 42, 43 are preferably formed to be the same height as the multiple heat dissipation fins 32 in the Z direction.

[0037] The heat dissipation fins 32 are surrounded by a bottom 41 and side walls 42, 43 of the insulating material 40. The thickness (Z direction) of the bottom 41 preferably coincides with the clearance between the heat dissipation fins 32 and the bottom surface 111 of the water jacket 110 at a temperature before the semiconductor device 10 generates heat. The thickness (Y direction) of the side walls 42, 43 preferably coincides with the clearance between the heat dissipation fins 32 and the side surfaces 112, 113 of the water jacket 110 at a temperature before the semiconductor device 10 generates heat. This configuration allows the insulation material 40 to fill the clearance between the heat dissipation fins 32 and the water jacket 110. In the example of FIG. 1 , the clearance between the heat dissipation fins 32 and the side surfaces 112, 113 of the water jacket 110 is larger than the clearance between the heat dissipation fins 32 and the bottom surface 111 of the water jacket 110, so the thicknesses of the side walls 42, 43 are thicker than the thickness of the bottom 41.

[0038] At least one of the bottom 41, the side wall 42, and the side wall 43 may have a thickness that is partially thicker or thinner. For example, the thickness of the bottom 41 and the side walls 42, 43 may be partially thickened so that the cooling water W can easily pass between some of the heat dissipation fins 32 by narrowing the clearance between the heat dissipation fins 32 and the water jacket 110, or conversely, the thickness of the bottom 41 may be partially thinned below the heat dissipation fins 32 that become hot and tend to expand downward (toward the negative side in the Z direction) due to thermal expansion.

[0039] The insulating material 40 may be an L-shaped plate having a bottom 41 and a side wall 42 or a side wall 43. Alternatively, an L-shaped insulating material having a portion of the bottom 41 on the negative side in the Y direction and the side wall 42, and an L-shaped insulating material having a portion of the bottom 41 on the positive side in the Y direction and the side wall 43 may be disposed.

[0040] FIG. 5A is a cross-sectional view taken along line IV-IV of FIG. 3 (a cross-sectional view corresponding to FIG. 4) in the first modified example.

[0041] As shown in FIG. 5A, an insulating material 50 in the first modification has a bottom 51 and side walls 52 and 53 facing each other, which are integral with each other, similar to the insulating material 40 described above.

[0042] Since the coolant W flows through multiple heat dissipation fins 32, it is more likely to become hotter when passing through the heat dissipation fins 32 downstream in the flow direction D than when passing through the heat dissipation fins 32 upstream in the flow direction D. Therefore, from the perspective of equalizing the heat dissipation performance between the heat dissipation fins 32 upstream in the flow direction D and the heat dissipation fins 32 downstream in the flow direction D, it is desirable to fill the clearance between the heat dissipation fins 32 and the water jacket 110 only downstream in the flow direction D, thereby increasing the flow rate (flow velocity) of the coolant W passing through the heat dissipation fins 32 downstream compared to upstream in the flow direction D. Therefore, the insulating material 50 is disposed only in a portion of the downstream side of the region where the heat dissipation fins 32 are disposed in the flow direction D (positive side of the X direction). The insulating material 50 shown in FIG. 5A is an example in which the length in the X direction is half that of the insulating material 40 shown in FIG. 4.

[0043] As shown in Fig. 5B, if the pressure loss when the insulating material 40 is not provided is set to "1," the pressure loss of the insulating material 40 shown in Fig. 4 (the entire area where the plurality of heat dissipation fins 32 are arranged) exceeds "2," but the pressure loss of the insulating material 50 shown in Fig. 5A (the downstream half of the area where the plurality of heat dissipation fins 32 are arranged) is less than "2." Therefore, it can be said that the insulating material 50 can reduce pressure loss more than the insulating material 40 while achieving uniform heat dissipation performance in the downstream part of the area where the plurality of heat dissipation fins 32 are arranged.

[0044] Matters other than those described in this first modified example can be the same as those described above, and therefore, explanations of overlapping matters will be omitted. Similarly, explanations of overlapping matters will be omitted for the second to sixth modified examples described later.

[0045] FIG. 6 is a cross-sectional view taken along line IV-IV of FIG. 3 (a cross-sectional view corresponding to FIG. 4) in the second modified example.

[0046] As shown in FIG. 6, an insulating material 60 in the second modification has a bottom 61 and side walls 62 and 63 facing each other, which are integral with each other, similar to the insulating materials 40 and 50 described above.

[0047] 5A , the insulating material 60 shown in Fig. 6 is different from the insulating material 50 shown in Fig. 5A in that the entire insulating material 60 is not disposed only in a portion on the downstream side of the area where the plurality of heat dissipation fins 32 are disposed, but rather, only the side walls 62, 63 are disposed only in a portion on the downstream side of the area where the plurality of heat dissipation fins 32 are disposed. In other words, the side walls 62, 63 are positioned so as to face only a portion of the plurality of heat dissipation fins 32 that are on the downstream side in the flow direction D.

[0048] FIG. 7 is a cross-sectional view taken along line IV-IV of FIG. 3 (a cross-sectional view corresponding to FIG. 4) in the third modified example.

[0049] As shown in FIG. 7, an insulating material 70 in the third modification has a bottom 71 and side walls 72 and 73 facing each other, which are integral with each other, similar to the insulating materials 40, 50, and 60 described above.

[0050] 5A , the insulating material 70 shown in Fig. 7 is different from the insulating material 50 shown in Fig. 5A in that the entire insulating material 70 is not disposed only in a portion on the downstream side of the area where the plurality of heat dissipation fins 32 are disposed, but rather only the bottom portion 71 is disposed only in a portion on the downstream side of the area where the plurality of heat dissipation fins 32 are disposed. In other words, the bottom portion 71 is positioned so as to face the tips 32 a of only a portion of the plurality of heat dissipation fins 32 that are on the downstream side in the flow direction D.

[0051] In addition, when the semiconductor element 10 is located above only the heat dissipation fins 32 in the central portion in the flow direction D, it is desirable to relatively improve the heat dissipation performance of the heat dissipation fins 32 in the central portion in the flow direction D. In this case, each part provided to face only some of the heat dissipation fins 32, such as the entire insulating material 50, the side walls 62 and 63 of the insulating material 60, and the bottom portion 71 of the insulating material 70, may be arranged only in the region where the heat dissipation fins 32 in the central portion in the flow direction D are arranged.

[0052] 5A , in the case where two semiconductor elements 10 are located on the upstream and downstream sides of the flow direction D and the heat dissipation performance of the heat dissipation fins 32 below each of the two semiconductor elements 10 is to be improved, an insulating material 50 facing only some of the heat dissipation fins 32 may be disposed below each of the two semiconductor elements 10. In this manner, a plurality of insulating materials 50 may be disposed at intervals in the flow direction D.

[0053] FIG. 8 is a cross-sectional view taken along line IV-IV of FIG. 3 (a cross-sectional view corresponding to FIG. 4) in the fourth modified example.

[0054] As shown in Fig. 8, the heat dissipation fins 32 are arranged at equal intervals in the X and Y directions, but one heat dissipation fin 32 located at the end on the positive side in the Y direction is missing (the missing heat dissipation fin 32 is shown by a dashed line). This allows the heat dissipation fins 32 to be considered to have recesses formed in a plan view (see Fig. 8). The heat dissipation fins 32 are arranged in a staggered pattern in the X direction such that the heat dissipation fins 32 are alternately arranged with their positions in the Y direction shifted by half the arrangement interval of the heat dissipation fins 32, but the arrangement intervals in both the X and Y directions are constant.

[0055] Similar to the insulating material 40 described above, the insulating material 80 integrally includes a bottom 81 and opposing side walls 82, 83. The side wall 83 is provided with a fin-side protrusion 83a that protrudes toward the plurality of heat dissipation fins 32. The fin-side protrusion 83a is inserted into a recess (a portion where one heat dissipation fin 32 is missing) of the plurality of heat dissipation fins 32. Preferably, the fin-side protrusion 83a is fitted into the recess of the plurality of heat dissipation fins 32. The fin-side protrusion 83a is formed at the same height in the Z direction as the plurality of heat dissipation fins 32 (i.e., the same height as the side wall 83). However, the fin-side protrusion 83a may protrude toward the plurality of heat dissipation fins 32 from a portion of the side wall 83 in the Z direction at a height lower than the plurality of heat dissipation fins 32, the recess of the plurality of heat dissipation fins 32, or the side wall 83. The recesses in the multiple heat dissipation fins 32 may be formed, for example, by shortening the length of the heat dissipation fins 32 at the positive end or the negative end of the Y direction, or by cutting out a portion of the positive end of the Y direction of the heat dissipation fin 32 at the positive end of the Y direction, or a portion of the negative end of the Y direction of the heat dissipation fin 32 at the negative end of the Y direction.

[0056] In this fourth modified example, the fin side protrusions 83a are provided only on the side walls 83 of the insulating material 80, but the fin side protrusions may be provided only on the side walls 82, or the fin side protrusions 83a may be provided on both the side walls 82 and 83.

[0057] Alternatively, a fin-side recess may be provided in the insulating material 80, and protrusions to be inserted into the fin-side recess may be provided on the plurality of heat dissipation fins 32. In this case, the protrusions of the plurality of heat dissipation fins 32 may be provided so as to protrude in the Y direction from at least one heat dissipation fin 32, for example, or may be provided by arranging additional heat dissipation fins 32.

[0058] FIG. 9 is a right side view of the semiconductor device showing the internal structure of the water jacket 110 in the fifth modified example.

[0059] FIG. 10 is a cross-sectional view taken along line IV-IV of FIG. 3 (a cross-sectional view corresponding to FIG. 4) in the fifth modified example.

[0060] 9 and 10 , like the insulating material 40 described above, the insulating material 90 integrally includes a bottom 91 and opposing side walls 92, 93. The bottom 91 is provided with a fin-side protrusion 91a that protrudes toward the heat dissipation fins 32. The fin-side protrusion 91a can be provided at any position, but in the example of FIG. 10 , it is provided at the center of the bottom 91 in the X and Y directions. Note that the fin-side protrusion 91a has a rectangular shape in a plan view (see FIG. 10 ), but may have another shape, such as a circle.

[0061] The fin side protrusions 91a are inserted into the recesses 32b of the plurality of heat dissipation fins 32. The recesses 32b are formed by shortening the length of at least one heat dissipation fin 32 (the heat dissipation fin 32 hatched in the opposite direction to the other heat dissipation fins 32 in FIG. 10 ) that faces the fin side protrusions 91a. The fin side protrusions 91a are inserted into the recesses 32b. Preferably, the fin side protrusions 91a are fitted into the recesses 32b of the plurality of heat dissipation fins 32.

[0062] Alternatively, a fin-side recess may be provided in the insulating material 90, and protrusions to be inserted into the fin-side recess may be provided on the plurality of heat dissipation fins 32. In this case, the protrusions of the plurality of heat dissipation fins 32 may be provided by, for example, making at least one heat dissipation fin 32 extend further in the negative Z direction than the other heat dissipation fins 32.

[0063] FIG. 11 is a right side view of a semiconductor device showing the internal structure of a water jacket 110 in a sixth modified example.

[0064] The water jacket 110 has side surfaces 112 and 113 each having recesses 112 a and 113 a on the insulating material 140 side.

[0065] Similar to the insulating material 40 described above, the insulating material 140 integrally includes a bottom 141 and opposing side walls 142, 143. The side walls 142, 143 are provided with jacket-side protrusions 142a, 143a that protrude away from the heat dissipation fins 32 and are inserted into the recesses 112a, 113a of the side surfaces 112, 113. Preferably, the jacket-side protrusions 142a, 143a are fitted into the recesses 112a, 113a of the side surfaces 112, 113.

[0066] The jacket-side convex portions 142a, 143a of the side walls 142, 143 of the insulating material 140 may be provided on only a portion of the insulating material 140 in the X direction and the Z direction. The jacket-side convex portions 142a, 143a of the insulating material 140 may also be provided on only one of the side walls 142, 143 or on the bottom 141. In this case, the recesses 112a, 113a of the water jacket 110 are also provided on only one of the side walls 112, 113 or on the bottom 111.

[0067] Alternatively, a convex portion may be provided on the water jacket 110 , and a jacket-side concave portion may be provided on the insulating material 140 that is recessed toward the heat dissipation fin 32 and inserted into the convex portion of the water jacket 110 .

[0068] 1 to 4 is removed, the water resistance in the clearance between the plurality of heat dissipation fins 32 and the water jacket 110 (bottom surface 111 and side surfaces 112, 113) is low, and the flow rate (flow velocity) of the cooling water W passing between the heat dissipation fins 32 is relatively reduced when the cooling water W flows through this clearance, making it impossible to fully demonstrate cooling performance. Therefore, adopting a structure that makes it difficult for the cooling water W to flow through the clearance or high-precision machining that reduces tolerances increases costs.

[0069] In addition, in the clearance between the plurality of heat dissipation fins 32 and the water jacket 110, when the plurality of heat dissipation fins 32 (cooler 30) are made of copper and the water jacket 110 is made of die-cast material, a local battery is formed due to the potential difference between the different metals when they are close to each other and filled with cooling water W, and aluminum hydroxide (Al(OH) ３ ) and other corrosion products are generated.

[0070] 15, the cooler 30 is plated with, for example, nickel 30a. The water jacket 110, which is made of aluminum, which has a relatively high ionization tendency, acts as an anode and generates electrons e － and aluminum ions Al ３＋The cooler 30 made of copper, which has a relatively low ionization tendency, becomes a cathode and dissolves the emitted electrons e － This electron e － and oxygen O ２ and cooling water W water H ２ The cathodic reaction with O produces hydroxide ions OH － is produced (cathode reaction). Then, aluminum hydroxide (Al(OH) ３ ) are generated. The corrosion products generated by the corrosion of the water jacket 110 in particular adhere to the spaces between the heat dissipation fins 32 and between the heat dissipation fins 32 and the water jacket 110, as shown by the corroded area C indicated by the dashed line in FIG. 16 . Furthermore, the corrosion of the water jacket 110 causes localized pitting corrosion to form in the water jacket 110.

[0071] In the present embodiment described above, the semiconductor module 1 includes a semiconductor element 10, a laminated substrate 20, which is an example of a substrate, a cooler 30, and an insulating material 40. The semiconductor element 10 is mounted on the laminated substrate 20. The cooler 30 has a heat dissipation base 31 and a plurality of heat dissipation fins 32 located on the opposite side of the heat dissipation base 31 from the laminated substrate 20, and is attached to a water jacket 110 for flowing cooling water W through the plurality of heat dissipation fins 32. The insulating material 40 integrally includes a bottom 41 extending along a flow direction D in which the cooling water W flows through the plurality of heat dissipation fins 32 and positioned so as to face at least a portion of the tips 32 a of the plurality of heat dissipation fins 32, and sidewalls 42, 43 extending from the bottom 41 toward the heat dissipation base 31 and positioned on at least a portion of the plurality of heat dissipation fins 32.

[0072] In this embodiment, the semiconductor device 100 includes the semiconductor module 1 and a water jacket 110 .

[0073] In these semiconductor modules 1 and semiconductor devices 100, an insulating material 40 is disposed in a clearance between the heat dissipation fins 32 and the water jacket 110 to prevent them from contacting each other due to dimensional variations during manufacturing. This fills the clearance between the heat dissipation fins 32 and the water jacket 110 with the insulating material 40, allowing the cooling water W to easily pass between the heat dissipation fins 32 and improving cooling performance. Furthermore, by disposing the insulating material 40 between the heat dissipation fins 32 and the water jacket 110, the formation of a local battery due to a potential difference can be suppressed. This prevents corrosion of the water jacket 110 or the heat dissipation fins 32, and prevents accumulated corrosion products from clogging the spaces between the heat dissipation fins 32, resulting in a deterioration in cooling performance and pressure loss. Furthermore, in the insulating material 40, at least one of the side walls 42 and 43 and the bottom 41 are integral with each other. Therefore, the insulating material 40 can be arranged along the bottom surface 111 and side surfaces 112, 113 of the water jacket 110 or along the tip 32a and side surfaces of the heat dissipation fins 32, thereby facilitating fixing and positioning of the insulating material 40 inside the water jacket 110. Therefore, according to this embodiment, assembly can be facilitated while improving cooling performance and preventing corrosion. Furthermore, compared to when the insulating material 40 is formed of a bottom 41 and separate side walls 42, 43, the semiconductor module 1 and the semiconductor device 100 can be simplified in configuration. Furthermore, the shape of the insulating material 40, which has an integral bottom 41 and side walls 42, 43, is easy to mold. Furthermore, improving the cooling performance (heat dissipation performance) as described above enables the semiconductor module 1 to be more compact and have higher output, reduce chip shrink costs, and improve reliability by suppressing heat generation temperatures. In addition, since the design can be carried out without concern for contact between the heat dissipation fins 32 and the bottom surface 111 of the water jacket 110 or the formation of a local battery due to this contact, it is also possible to relax the tolerance requirements regarding the flatness of the heat dissipation fins 32 and the water jacket 110.

[0074] In this embodiment, the side walls 42 and 43 of the insulating material 40 face each other, and the heat dissipation fins 32 are surrounded by the bottom 41 and the side walls 42 and 43 .

[0075] As a result, the insulating material 40 is disposed in the clearance between the plurality of heat dissipation fins 32 and the bottom surface 111 and the side surfaces 112, 113 of the water jacket 110, thereby improving cooling performance and preventing corrosion on all of the bottom surface 111, the side surfaces 112, and the side surfaces 113. Furthermore, because the insulating material 40 can be disposed along the interior of the water jacket 110, it is possible to further facilitate assembly of the insulating material 40 inside the water jacket 110. Furthermore, compared to when the insulating material 40 is separate from the bottom 41 and the two side walls 42, 43, the configuration can be further simplified.

[0076] In addition, in the first variant (Figure 5A) and the third variant (Figure 7) of this embodiment, the bottoms 51, 71 of the insulating materials 50, 70 are positioned so as to face the tips 32a of only a portion of the heat dissipation fins 32 that are downstream in the flow direction D among the multiple heat dissipation fins 32.

[0077] As a result, when passing through the downstream radiator fins 32 where the temperature of the cooling water W is likely to be higher than when passing through the upstream radiator fins 32 in the flow direction D, the cooling water W is less likely to flow through the clearance between the radiator fins 32 and the bottom surface 111 of the water jacket 110. Therefore, the heat dissipation performance of the downstream radiator fins 32 in the flow direction D can be made closer to that of the upstream radiator fins 32.

[0078] In addition, in the first variant (Figure 5A) and the second variant (Figure 6) of this embodiment, the side walls 52, 62 of the insulating materials 50, 60 are positioned so as to face only a portion of the heat dissipation fins 32 that are downstream in the flow direction D among the multiple heat dissipation fins 32.

[0079] As a result, when passing through the downstream radiator fins 32 where the temperature of the coolant W is likely to increase more than when passing through the upstream radiator fins 32 in the flow direction D, the coolant W is less likely to flow through the clearance between the radiator fins 32 and the side surfaces 112, 113 of the water jacket 110. Therefore, the heat dissipation performance of the downstream radiator fins 32 in the flow direction D can be made similar to that of the upstream radiator fins 32.

[0080] In addition, in the fourth (Figure 8) and fifth (Figures 9 and 10) variants of this embodiment, the multiple heat dissipation fins 32 include at least one of a recess 32b (or a recess formed by the absence of one heat dissipation fin 32) into which the fin side protrusions 83a and 91a provided on the insulating material 80 and 90 are inserted, and a protrusion inserted into the fin side recess provided on the insulating material 80 and 90.

[0081] This allows the insulating materials 80, 90 to be positioned relative to the heat dissipation fins 32, making it easier to assemble the insulating materials 80, 90 inside the water jacket 110. In addition, it is possible to prevent the insulating materials 40 from shifting in position due to the water pressure when the cooling water W flows.

[0082] In addition, in a sixth variant of this embodiment (Figure 11), the insulating material 140 includes at least one of jacket side convex portions 142a, 143a that are inserted into concave portions 112a provided in the water jacket 110, and jacket side concave portions into which convex portions provided in the water jacket 110 are inserted.

[0083] This allows the insulating material 140 to be directly positioned in the water jacket 110, making it even easier to assemble the insulating material 140 inside the water jacket 110. In addition, it is possible to prevent the insulating material 140 from shifting in position due to the water pressure when the cooling water W flows.

[0084] Below, some of the inventions described in the specification and drawings of this application will be additionally noted.

[0085] <Supplementary Note 1> A semiconductor module comprising: a semiconductor element; a substrate on which the semiconductor element is mounted; a cooler having a heat dissipation base and a plurality of heat dissipation fins located on the opposite side of the heat dissipation base from the substrate, the cooler being attached to a water jacket for flowing cooling water through the plurality of heat dissipation fins; and an insulating material having, integrally therewith, a bottom extending in the direction in which the cooling water flows through the plurality of heat dissipation fins and facing at least a portion of the tips of the plurality of heat dissipation fins, and a sidewall extending from the bottom toward the heat dissipation base and facing at least a portion of the heat dissipation fins.

[0086] <Supplementary Note 2> The semiconductor module according to Supplementary Note 1, characterized in that the side walls of the insulating material have a first side wall and a second side wall arranged opposite the first side wall, and the plurality of heat dissipation fins are surrounded by the bottom, the first side wall, and the second side wall in a side view.

[0087] <Supplementary Note 3> The semiconductor module according to Supplementary Note 1 or 2, wherein the bottom of the insulating material is positioned to face the tips of only a portion of the heat dissipation fins that are downstream in the flow direction among the plurality of heat dissipation fins.

[0088] <Supplementary Note 4> The semiconductor module according to any one of Supplementary Notes 1 to 3, wherein the side wall of the insulating material is positioned to face only a portion of the plurality of heat dissipation fins that are downstream in the flow direction.

[0089] <Supplementary Note 5> The semiconductor module according to any one of Supplementary Notes 1 to 4, wherein the plurality of heat dissipation fins include at least one of recesses into which fin-side protrusions provided in the insulating material are inserted, and protrusions that are inserted into fin-side recesses provided in the insulating material.

[0090] <Supplementary Note 6> The semiconductor module according to Supplementary Note 1, wherein the insulating material includes at least one of a jacket-side convex portion that protrudes on the side opposite to the heat dissipation fins and a jacket-side concave portion that is recessed toward the heat dissipation fins.

[0091] <Supplementary Note 7> The semiconductor module according to Supplementary Note 1, wherein the bottom of the insulating material has a size equal to or larger than an area in which the plurality of heat dissipation fins are arranged.

[0092] <Supplementary Note 8> The semiconductor module according to Supplementary Note 1, wherein the side wall of the insulating material has a size equal to or larger than an area in which the plurality of heat dissipation fins are arranged in the flow direction.

[0093] <Supplementary Note 9> A semiconductor device comprising: the semiconductor module according to any one of Supplementary Notes 1 to 8; and the water jacket.

[0094] <Supplementary Note 10> The semiconductor device according to Supplementary Note 9, wherein the water jacket has a bottom surface on which the bottom of the insulating material is disposed and a side surface on which the sidewall of the insulating material is disposed.

[0095] As described above, the present invention has the effect of facilitating assembly in semiconductor modules and semiconductor devices while improving cooling performance and preventing corrosion, and is particularly useful for inverter devices for industrial or electrical equipment.

[0096] This application is based on Japanese Patent Application No. 2024-069640, filed on April 23, 2024, the contents of which are incorporated herein in their entirety.

[0097] REFERENCE SIGNS LIST 1 semiconductor module 10 semiconductor element 20 laminated substrate (substrate) 21 insulating plate 22 circuit board 23 heat sink 30 cooler 30a nickel plating 31 heat sink base 31a upper surface 31b lower surface 32 heat sink fin 32a tip 32b recess 40, 50, 60, 70, 80, 90, 140 insulating material 41, 51, 61, 71, 81, 91, 141 bottom 42, 43, 52, 53, 62, 63, 72, 73, 82, 83, 92, 93, 142, 143 side wall 83a, 91a fin side convex portion 142a, 143a jacket side convex portion 100 semiconductor device 110 water jacket 111 bottom surface 112, 113 Side surface 112a, 113a Recess 114 Inlet pipe 115 Outlet pipe C Corroded portion D Flow direction S1, S2 Joint material W Cooling water

Claims

1. A semiconductor module comprising: a semiconductor element; a substrate on which the semiconductor element is mounted; a cooler having a heat dissipation base and a plurality of heat dissipation fins located on the opposite side of the heat dissipation base from the substrate, the cooler being attached to a water jacket for flowing cooling water through the plurality of heat dissipation fins; and an insulating material having, integrally therewith, a bottom extending in the direction in which the cooling water flows through the plurality of heat dissipation fins and facing at least a portion of the tips of the plurality of heat dissipation fins, and a sidewall extending from the bottom toward the heat dissipation base and facing at least a portion of the plurality of heat dissipation fins.

2. The semiconductor module according to claim 1, characterized in that the side walls of the insulating material have a first side wall and a second side wall arranged opposite the first side wall, and the plurality of heat dissipation fins are surrounded by the bottom, the first side wall and the second side wall in a side view.

3. The semiconductor module according to claim 1, characterized in that the bottom of the insulating material is positioned so as to face the tips of only a portion of the plurality of heat dissipation fins that are located downstream in the flow direction.

4. The semiconductor module according to claim 1, characterized in that the side wall of the insulating material is positioned so as to face only a portion of the plurality of heat dissipation fins on the downstream side in the flow direction.

5. The semiconductor module according to claim 1, characterized in that the plurality of heat dissipation fins include at least one of recesses into which fin-side protrusions provided in the insulating material are inserted, and protrusions that are inserted into fin-side recesses provided in the insulating material.

6. The semiconductor module according to claim 1, characterized in that the insulating material includes at least one of a jacket-side convex portion that protrudes on the side opposite to the heat dissipation fins and a jacket-side concave portion that is recessed toward the heat dissipation fins.

7. The semiconductor module according to claim 1, wherein the bottom of the insulating material has a size equal to or larger than the area where the plurality of heat dissipation fins are arranged.

8. The semiconductor module according to claim 1, wherein the side wall of the insulating material has a size equal to or larger than the area in the flow direction in which the plurality of heat dissipation fins are arranged.

9. A semiconductor device comprising: a semiconductor module according to any one of claims 1 to 8; and the water jacket.

10. The semiconductor device according to claim 9, wherein the water jacket has a bottom surface on which the bottom of the insulating material is disposed and a side surface on which the sidewall of the insulating material is disposed.

Images