Cooler and cooling structure for semiconductor device

Abstract

This cooler comprises: a housing that includes an opening, an inner space section, and a bottom section; and a partition wall that extends up from the bottom section in a first direction and is accommodated in the inner space section. The housing is provided with an inflow passage and an outflow passage each connected to the inner space section. The inner space section includes a first storage section and a second storage section demarcated by the partition wall. The first storage section is connected to the inflow passage. The second storage section is connected to the outflow passage. The partition wall includes an overflow section that overlaps the opening section when viewed in the first direction and is the most distant section from the base section. The overflow section is positioned between the bottom section and the opening.

Description

Cooler and cooling structure for semiconductor device

[0001] The present disclosure relates to a cooler and a cooling structure for a semiconductor device in which a semiconductor device is attached to the cooler.

[0002] Patent Document 1 discloses an example of a cooler in which a semiconductor device is disposed. The cooler includes a housing having a hollow region and a heat sink. The housing has an opening that leads to the hollow region. The heat sink is attached to the housing so as to cover the opening. A portion of the heat sink is housed in the hollow region. The semiconductor device is joined to a portion of the heat sink that protrudes from the hollow region. When a refrigerant is caused to flow down the hollow region, the refrigerant comes into contact with the heat sink. This allows the semiconductor device to be cooled via the heat sink.

[0003] In the cooler disclosed in Patent Document 1, the radiator interferes with the direction of the refrigerant flow, which causes energy loss in the refrigerant flow and may prevent the refrigerant from reaching the entire radiator portion housed in the hollow region, resulting in a decrease in the cooling efficiency of the cooler.

[0004] International Publication No. 2017 / 094370

[0005] An object of the present disclosure is to provide an improved cooler and cooling structure for a semiconductor device. In particular, in view of the above circumstances, an object of the present disclosure is to provide a cooler that can improve cooling efficiency while suppressing energy loss in the flow of refrigerant, and an attachment structure for the cooler and the semiconductor device.

[0006] A cooler provided by a first aspect of the present disclosure includes a housing having an opening located on one side in a first direction, an internal space connected to the opening, and a bottom located on the opposite side of the internal space from the opening and defining a portion of the internal space; and a partition wall rising from the bottom in the first direction and housed in the internal space. The housing has an inlet channel and an outlet channel, each of which connects to the internal space. The internal space includes a first storage section and a second storage section separated by the partition wall. The first storage section is connected to the inlet channel, and the second storage section is connected to the outlet channel. The partition wall has an overflow section that overlaps the opening when viewed in the first direction and is farthest from the bottom. The overflow section is located between the bottom and the opening.

[0007] A cooling structure for a semiconductor device provided by a second aspect of the present disclosure includes the cooler provided by the first aspect of the present disclosure, wherein the overflow portion is spaced apart from the opening in the first direction, and a semiconductor device attached to the cooler, the semiconductor device being attached to the housing, and the semiconductor device blocking the opening.

[0008] A cooling structure for a semiconductor device provided by a third aspect of the present disclosure is the cooler provided by the first aspect of the present disclosure, further comprising a base surface facing the opening and a lid member closing the opening. The overflow section includes a cooler spaced from the base surface and a semiconductor device attached to the cooler. The semiconductor device is attached to the lid member. When viewed in the first direction, the semiconductor device overlaps the opening.

[0009] A fourth aspect of the present disclosure provides a mounting structure for a cooler and a semiconductor device, comprising: a cooler having a plurality of internal spaces, each recessed in a first direction and arranged in a direction perpendicular to the first direction; and a plurality of semiconductor devices mounted on the cooler. When viewed in the first direction, the semiconductor devices individually overlap the internal spaces. The cooler is provided with a plurality of inlet channels and a plurality of outlet channels set as a system different from the inlet channels. The inlet channels are individually connected to the internal spaces. The outlet channels are individually connected to the internal spaces.

[0010] According to the above configuration, it is possible to improve the cooling efficiency while suppressing the energy loss in the flow of the refrigerant.

[0011] Other features and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

[0012] FIG. 1 is an exploded perspective view of a cooler according to a first embodiment of the present disclosure. FIG. 2 is a plan view of the cooler shown in FIG. 1. FIG. 3 is a bottom view of the cooler shown in FIG. 1. FIG. 4 is a perspective view of a housing included in the cooler shown in FIG. 1, with the bottom portion omitted. FIG. 5 is a cross-sectional view taken along line V-V in FIG. 2. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 2. FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 2. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 2. FIG. 9 is a perspective view of a semiconductor device included in the cooling structure of the semiconductor device shown in FIG. 22. FIG. 10 is a plan view of the semiconductor device shown in FIG. 9. FIG. 11 is a plan view corresponding to FIG. 10, seen through the sealing resin. FIG. 12 is a partially enlarged view of FIG. 11. FIG. 13 is a plan view corresponding to FIG. 10, seen through the first conductive member, with the sealing resin and second conductive member omitted. 14 is a right side view of the semiconductor device shown in FIG. 9 . FIG. 15 is a bottom view of the semiconductor device shown in FIG. 9 . FIG. 16 is a cross-sectional view taken along line XVI-XVI in FIG. 11 . FIG. 17 is a cross-sectional view taken along line XVII-XVII in FIG. 11 . FIG. 18 is a partially enlarged view of the first element and its periphery shown in FIG. 17 . FIG. 19 is a partially enlarged view of the second element and its periphery shown in FIG. 17 . FIG. 20 is a cross-sectional view taken along line XX-XX in FIG. 11 . FIG. 21 is a cross-sectional view taken along line XXI-XXI in FIG. 11 . FIG. 22 is a plan view of a cooling structure of a semiconductor device according to a first embodiment of the present disclosure. FIG. 23 is a cross-sectional view taken along line XXIII-XXIII in FIG. 22 . FIG. 24 is an exploded perspective view of a cooler according to a second embodiment of the present disclosure. FIG. 25 is a plan view of the cooler shown in FIG. 24 . 26 is a cross-sectional view taken along line XXVI-XXVI in FIG. 25. FIG. 27 is a cross-sectional view taken along line XXVII-XXVII in FIG. 25. FIG. 28 is a perspective view of a lid member provided in the cooler shown in FIG. 24. FIG. 29 is a plan view of a cooling structure for a semiconductor device according to a second embodiment of the present disclosure. FIG. 30 is a cross-sectional view taken along line XXX-XXX in FIG. 29. FIG. 31 is a plan view of a cooler according to a third embodiment of the present disclosure, seen through the lid member. FIG. 32 is a cross-sectional view taken along line XXXII-XXXII in FIG. 31. FIG. 33 is a cross-sectional view taken along line XXXIII-XXXIII in FIG. 31.Fig. 34 is a plan view of a cooler according to a fourth embodiment of the present disclosure. Fig. 35 is a cross-sectional view taken along line XXXV-XXXV in Fig. 34. Fig. 36 is a cross-sectional view taken along line XXXVI-XXXVI in Fig. 34. Fig. 37 is a cross-sectional view taken along line XXXVII-XXXVII in Fig. 34. Fig. 38 is a plan view of a cooling structure for a semiconductor device according to a third embodiment of the present disclosure.

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present disclosure will be described with reference to the accompanying drawings.

[0014] First Embodiment (Cooler): A cooler A10 according to a first embodiment of the present disclosure will be described with reference to Figures 1 to 8. The cooler A10 is used to cool a semiconductor device B equipped with a cooling structure C10, which will be described later. The cooler A10 includes a housing 70 and a partition wall 81. For ease of understanding, a bottom 72 of the housing 70, which will be described later, is not shown in Figure 4.

[0015] In the description of the cooler A10, for convenience, the normal direction to the main surface 71A of the housing 70, which will be described later, will be referred to as the "first direction z." The direction perpendicular to the first direction z will be referred to as the "second direction x." The direction perpendicular to the first direction z and the second direction x will be referred to as the "third direction y." The first direction z, the second direction x, and the third direction y will also be applied to the description of the semiconductor device B and the cooling structure C10, which will be described later.

[0016] As shown in FIG. 1 , the housing 70 has a main body 71 and a bottom 72. The bottom 72 is attached to the main body 71. In the cooler A10, the main body 71 and the bottom 72 are each made of a material containing resin. Alternatively, the main body 71 and the bottom 72 may each be made of a material containing metal. In implementing the present disclosure, the materials for the main body 71 and the bottom can be freely selected.

[0017] 1, 2, and 5 to 7, the main body 71 has a main surface 71A and an opening 711. The main surface 71A faces one side in the first direction z. The opening 711 is located on one side in the first direction z. The opening 711 is connected to and surrounded by the main surface 71A.

[0018] 5 to 7 , the bottom 72 is located on the opposite side of the opening 711 of the main body 71 with respect to an inner hollow 73 (described later) as a reference. The bottom 72 closes the main body 71. The bottom 72 has a back surface 72A. The back surface 72A faces the opposite side to the main surface 71A of the main body 71 in the first direction z.

[0019] 2 and 4 to 8, the housing 70 has an internal cavity 73. The internal cavity 73 is connected to an opening 711 of the main body 71. The internal cavity 73 is located inside the main body 71. The main body 71 and the bottom 72 each define a portion of the internal cavity 73.

[0020] As shown in FIGS. 1 , 3 , and 5 , the bottom 72 is provided with an inlet channel 74 and an outlet channel 75. The inlet channel 74 and the outlet channel 75 are each connected to the internal cavity 73 and penetrate the bottom 72 in the first direction z. The inlet channel 74 and the outlet channel 75 are spaced apart from each other in the third direction y. The inlet channel 74 has an inlet portion 741. The inlet portion 741 is connected to the back surface 72A. The outlet channel 75 has an outlet portion 751. The outlet portion 751 is connected to the back surface 72A. A connecting member (not shown) is attached to each of the inlet portion 741 and the outlet portion 751 to supply a refrigerant from the outside or to discharge a refrigerant to the outside.

[0021] As shown in FIGS. 2 and 4 to 8 , the partition wall 81 is housed in the hollow portion 73 of the housing 70. The partition wall 81 rises from the bottom portion 72 in the first direction z. In the cooler A10, the partition wall 81 is made of a material containing resin. The partition wall 81 is integrated with the main body portion 71. Alternatively, the partition wall 81 may be attached to the main body portion 71. The partition wall 81 is exposed from an opening 711 of the main body portion 71.

[0022] 2 and 4, the inner space 73 includes a first storage section 731 and a second storage section 732 separated by a partition wall 81. As shown in FIGS. 3 and 5, the first storage section 731 is connected to the inflow channel 74. The second storage section 732 is connected to the outflow channel 75.

[0023] 1, 2, and 5 to 7, the partition wall 81 has an overflow portion 811. When viewed in the first direction z, the overflow portion 811 overlaps the opening 711 of the main body portion 71. The overflow portion 811 is farthest from the bottom portion 72. The overflow portion 811 is located between the bottom portion 72 and the opening 711 in the first direction z. In the cooler A10, the overflow portion 811 is farthest from the opening 711 in the first direction z.

[0024] In the cooler A10, a refrigerant is supplied from the outside through the inlet 741. The supplied refrigerant flows into the first storage portion 731 through the inlet channel 74. As the supply of refrigerant continues, the liquid level of the refrigerant that has flowed into the first storage portion 731 rises. When the liquid level of the refrigerant subsequently rises to a position farther from the bottom 72 than the overflow portion 811 of the partition wall 81, the refrigerant flows over the overflow portion 811 and down into the second storage portion 732. The refrigerant that has flowed down into the second storage portion 732 is discharged to the outside from the outlet 751 via the outlet channel 75. Therefore, the flow of the refrigerant in the internal space 73 includes a flow component in the first direction z. The refrigerant discharged to the outside from the outlet 751 is cooled again. Subsequently, by supplying the refrigerant again through the inlet 741, the refrigerant can be circulated within the cooler A10 and outside.

[0025] 2 to 4 , the partition wall 81 includes a first partition wall 81A and a second partition wall 81B. When viewed in the first direction z, the first partition wall 81A and the second partition wall 81B overlap the opening 711 of the main body portion 71. The first partition wall 81A and the second partition wall 81B are spaced apart from each other in the second direction x. Each of the first partition wall 81A and the second partition wall 81B extends in the third direction y. Each of the first partition wall 81A and the second partition wall 81B includes an overflow portion 811.

[0026] 2 and 4 , in the cooler A10, the first storage portion 731 is located between the first partition wall 81A and the second partition wall 81B. When viewed in the first direction z, the first storage portion 731 overlaps with the center C of the opening 711 of the main body portion 71. Alternatively, by reversing the arrangement of the inlet channel 74 and the outlet channel 75, a configuration can be adopted in which the second storage portion 732 is located between the first partition wall 81A and the second partition wall 81B. Therefore, in the cooler A10, either the first partition wall 81A or the second partition wall 81B is located between the first partition wall 81A and the second partition wall 81B.

[0027] As shown in FIGS. 2 to 4 , the partition wall 81 includes a third partition wall 81C, a fourth partition wall 81D, and a fifth partition wall 81E. The third partition wall 81C is located on the opposite side of the inlet channel 74 from the first partition wall 81A and the second partition wall 81B in the third direction y. The third partition wall 81C connects the first partition wall 81A and the second partition wall 81B. The fourth partition wall 81D and the fifth partition wall 81E are located on the opposite side of the third partition wall 81C from the first partition wall 81A and the second partition wall 81B. The fourth partition wall 81D connects the first partition wall 81A and the main body portion 71. The fifth partition wall 81E connects the second partition wall 81B and the main body portion 71. Each of the third partition wall 81C, the fourth partition wall 81D, and the fifth partition wall 81E includes a first curved surface facing the first storage portion 731 and a second curved surface facing the second storage portion 732.

[0028] (Semiconductor Device B) Next, a semiconductor device B equipped with a cooling structure C10 (described later) will be described with reference to FIGS. 9 to 21 . The semiconductor device B includes a base material 11, a first conductive layer 121, a second conductive layer 122, a first input terminal 13, an output terminal 14, a second input terminal 15, a first signal terminal 161, a second signal terminal 162, a plurality of semiconductor elements 21, a first conductive member 31, a second conductive member 32, and a sealing resin 50. The semiconductor device B further includes a third signal terminal 171, a fourth signal terminal 172, a pair of fifth signal terminals 181, a pair of sixth signal terminals 182, a seventh signal terminal 19, a pair of thermistors 22, and a pair of control wirings 60. For ease of understanding, FIGS. 11 and 12 show the sealing resin 50 in a transparent manner. In FIG. 11 , the transparent sealing resin 50 is indicated by an imaginary line (double-dashed line). 13, for ease of understanding, the first conductive member 31 is shown in perspective, and the second conductive member 32 and the sealing resin 50 are omitted. In Fig. 13, the first conductive member 31 is shown in perspective by an imaginary line. Furthermore, in Fig. 11, line XVII-XVII is shown by a dashed line.

[0029] The semiconductor device B converts a DC power supply voltage applied to the first input terminal 13 and the second input terminal 15 into AC power using the semiconductor element 21. The converted AC power is input from the output terminal 14 to a power supply target such as a motor.

[0030] As shown in FIGS. 17 to 19 , the substrate 11 is located on the opposite side of the semiconductor elements 21 in the first direction z, with the first conductive layer 121 and the second conductive layer 122 sandwiched therebetween. The substrate 11 supports the first conductive layer 121 and the second conductive layer 122. In the semiconductor device B, the substrate 11 is made of a DBC (Direct Bonded Copper) substrate. As shown in FIGS. 17 to 19 , the substrate 11 includes an insulating layer 111, an intermediate layer 112, and a heat dissipation layer 113. The substrate 11 is covered with a sealing resin 50 except for a portion of the heat dissipation layer 113.

[0031] As shown in FIGS. 17 to 19 , the insulating layer 111 includes a portion interposed between the intermediate layer 112 and the heat dissipation layer 113 in the first direction z. The insulating layer 111 is made of a material with relatively high thermal conductivity. For example, the insulating layer 111 is made of ceramics containing aluminum nitride (AlN). The insulating layer 111 may be made of an insulating resin sheet in addition to ceramics. The thickness of the insulating layer 111 is thinner than the thickness of each of the first conductive layer 121 and the second conductive layer 122.

[0032] 17 to 19 , the intermediate layer 112 is located between the insulating layer 111 and the first and second conductive layers 121 and 122 in the first direction z. The intermediate layer 112 includes a pair of regions spaced apart from each other in the second direction x. The composition of the intermediate layer 112 includes copper (Cu). As shown in FIG. 13 , the intermediate layer 112 is surrounded by the periphery of the insulating layer 111 when viewed in the first direction z.

[0033] 17 to 19, the heat dissipation layer 113 is located on the opposite side of the intermediate layer 112 in the first direction z, with the insulating layer 111 sandwiched therebetween. As shown in FIG. 15, the heat dissipation layer 113 is exposed from the sealing resin 50. The heat dissipation layer 113 contains copper. The thickness of the heat dissipation layer 113 is greater than the thickness of the insulating layer 111. When viewed in the first direction z, the heat dissipation layer 113 is surrounded by the periphery of the insulating layer 111.

[0034] As shown in FIGS. 17 to 19 , the first conductive layer 121 and the second conductive layer 122 are bonded to the substrate 11. The first conductive layer 121 and the second conductive layer 122 contain copper. The first conductive layer 121 and the second conductive layer 122 are spaced apart in the second direction x. As shown in FIGS. 16 and 17 , the first conductive layer 121 has a first main surface 121A and a first back surface 121B facing opposite sides in the first direction z. The first main surface 121A faces the plurality of semiconductor elements 21. As shown in FIG. 18 , the first back surface 121B is bonded to one of a pair of regions of the intermediate layer 112 via a first adhesive layer 123. The first adhesive layer 123 is, for example, a brazing material containing silver (Ag) in its composition. 16 and 17 , the second conductive layer 122 has a second main surface 122A and a second back surface 122B that face opposite each other in the first direction z. The second main surface 122A faces the same side as the first main surface 121A in the first direction z. As shown in FIG. 19 , the second back surface 122B is bonded to the other of the pair of regions of the intermediate layer 112 via a first adhesive layer 123.

[0035] As shown in FIGS. 13 and 17 , each of the multiple semiconductor elements 21 is mounted on either the first conductive layer 121 or the second conductive layer 122. The semiconductor element 21 is, for example, a metal-oxide-semiconductor field-effect transistor (MOSFET). Alternatively, the semiconductor element 21 may be a switching element such as an insulated gate bipolar transistor (IGBT), or a diode. In the description of semiconductor device B, the semiconductor element 21 is an n-channel MOSFET with a vertical structure. The semiconductor element 21 includes a compound semiconductor substrate. The compound semiconductor substrate contains silicon carbide (SiC).

[0036] 13 , in the semiconductor device B, the multiple semiconductor elements 21 include multiple first elements 21A and multiple second elements 21B. The structure of each of the multiple second elements 21B is the same as the structure of each of the multiple first elements 21A. The multiple first elements 21A are mounted on a first main surface 121A of a first conductive layer 121. The multiple first elements 21A are arranged along the third direction y. The multiple second elements 21B are mounted on a second main surface 122A of a second conductive layer 122. The multiple second elements 21B are arranged along the third direction y.

[0037] As shown in FIGS. 13, 18, and 19, the plurality of semiconductor elements 21 have a first electrode 211, a second electrode 212, a third electrode 213, and a fourth electrode 214.

[0038] 18 and 19 , the first electrode 211 faces either the first conductive layer 121 or the second conductive layer 122. A current corresponding to the power before being converted by the semiconductor element 21 flows through the first electrode 211. In other words, the first electrode 211 corresponds to the drain electrode of the semiconductor element 21.

[0039] 18 and 19 , the second electrode 212 is located on the opposite side of the first electrode 211 in the first direction z. A current corresponding to the power converted by the semiconductor element 21 flows through the second electrode 212. In other words, the second electrode 212 corresponds to the source electrode of the semiconductor element 21.

[0040] 18 and 19 , the third electrode 213 is located on the same side as the second electrode 212 in the first direction z. A gate voltage for driving the semiconductor element 21 is applied to the third electrode 213. That is, the third electrode 213 corresponds to the gate electrode of the semiconductor element 21. As shown in FIG. 13 , the area of ​​the third electrode 213 is smaller than the area of ​​the second electrode 212 when viewed in the first direction z.

[0041] 13 , the fourth electrode 214 is located on the same side as the second electrode 212 in the first direction z, and is located next to the third electrode 213 in the third direction y. The potential of the fourth electrode 214 is equal to the potential of the second electrode 212.

[0042] As shown in FIGS. 18 and 19 , the conductive bonding layer 23 is interposed between either the first conductive layer 121 or the second conductive layer 122 and the first electrode 211 of one of the multiple semiconductor elements 21. The conductive bonding layer 23 is, for example, solder. Alternatively, the conductive bonding layer 23 may include a sintered body of metal particles. The first electrodes 211 of the multiple first elements 21A are conductively bonded to the first main surface 121A of the first conductive layer 121 via the conductive bonding layer 23. As a result, the first electrodes 211 of the multiple first elements 21A are electrically connected to the first conductive layer 121. The first electrodes 211 of the multiple second elements 21B are conductively bonded to the second main surface 122A of the second conductive layer 122 via the conductive bonding layer 23. As a result, the first electrodes 211 of the multiple second elements 21B are electrically connected to the second conductive layer 122.

[0043] As shown in FIGS. 11 and 17 , the first input terminal 13 is located on the opposite side of the second conductive layer 122 in the second direction x, with the first conductive layer 121 sandwiched therebetween, and is connected to the first conductive layer 121. This allows the first input terminal 13 to be electrically connected to the first electrodes 211 of the multiple first elements 21A via the first conductive layer 121. The first input terminal 13 is a P terminal (positive electrode) to which a DC power supply voltage to be converted is applied. The first input terminal 13 extends from the first conductive layer 121 in the second direction x. The first input terminal 13 has a covering portion 13A and an exposed portion 13B. As shown in FIG. 17 , the covering portion 13A is connected to the first conductive layer 121 and is covered with a sealing resin 50. The covering portion 13A is flush with the first main surface 121A of the first conductive layer 121. The exposed portion 13B extends from the covered portion 13A in the second direction x and is exposed from the sealing resin 50 .

[0044] As shown in FIGS. 11 and 16 , the output terminal 14 is located on the opposite side of the first conductive layer 121 in the second direction x, with the second conductive layer 122 sandwiched therebetween, and is connected to the second conductive layer 122. This allows the output terminal 14 to be electrically connected to the first electrodes 211 of the plurality of second elements 21B via the second conductive layer 122. AC power converted by the semiconductor elements 21 is output from the output terminal 14. In the semiconductor device B, the output terminal 14 includes a pair of regions spaced apart from each other in the third direction y. Alternatively, the output terminal 14 may have a single configuration without a pair of regions. The output terminal 14 includes a covering portion 14A and an exposed portion 14B. As shown in FIG. 16 , the covering portion 14A is connected to the second conductive layer 122 and covered with a sealing resin 50. The covering portion 14A is flush with the second main surface 122A of the second conductive layer 122. The exposed portion 14B extends from the covered portion 14A in the second direction x and is exposed from the sealing resin 50.

[0045] As shown in FIGS. 11 and 16 , the second input terminal 15 is located on the same side as the first input terminal 13 with respect to the first conductive layer 121 and the second conductive layer 122 in the second direction x, but is spaced apart from the first conductive layer 121 and the second conductive layer 122. The second input terminal 15 is electrically connected to the second electrodes 212 of the plurality of second elements 21B. The second input terminal 15 is an N terminal (negative electrode) to which a DC power supply voltage to be converted is applied. The second input terminal 15 includes a pair of regions spaced apart from each other in the third direction y. The first input terminal 13 is located between the pair of regions in the third direction y. The second input terminal 15 has a covering portion 15A and an exposed portion 15B. As shown in FIG. 16 , the covering portion 15A is spaced apart from the first conductive layer 121 and is covered with sealing resin 50. The exposed portion 15B extends from the covering portion 15A in the second direction x and is exposed from the sealing resin 50.

[0046] The pair of control wirings 60 constitute part of the conductive paths between the first signal terminal 161, the second signal terminal 162, the third signal terminal 171, the fourth signal terminal 172, the pair of fifth signal terminals 181, and the pair of sixth signal terminals 182, and the plurality of semiconductor elements 21. As shown in FIGS. 11 to 13 , the pair of control wirings 60 includes a first wiring 601 and a second wiring 602. In the second direction x, the first wiring 601 is located between the plurality of first elements 21A and the first input terminal 13 and the second input terminal 15. The first wiring 601 is bonded to the first main surface 121A of the first conductive layer 121. The first wiring 601 also constitutes part of the conductive path between the seventh signal terminal 19 and the first conductive layer 121. In the second direction x, the second wiring 602 is located between the plurality of second elements 21B and the output terminal 14. The second wiring 602 is joined to the second main surface 122A of the second conductive layer 122. As shown in Figures 18 and 19, the pair of control wirings 60 has an insulating layer 61, multiple wiring layers 62, a metal layer 63, and multiple sleeves 64. The pair of control wirings 60 is covered with the sealing resin 50 except for a portion of each of the multiple sleeves 64.

[0047] 18 and 19 , the insulating layer 61 includes a portion interposed between the plurality of wiring layers 62 and the metal layer 63 in the first direction z. The insulating layer 61 is made of, for example, ceramics. The insulating layer 61 may be made of an insulating resin sheet instead of ceramics.

[0048] 18 and 19 , the multiple wiring layers 62 are located on one side of the insulating layer 61 in the first direction z. The multiple wiring layers 62 contain copper. As shown in Fig. 13 , the multiple wiring layers 62 include a first wiring layer 621, a second wiring layer 622, a pair of third wiring layers 623, a fourth wiring layer 624, and a fifth wiring layer 625. The pair of third wiring layers 623 are adjacent to each other in the third direction y.

[0049] 18 and 19 , the metal layer 63 is located on the opposite side of the multiple wiring layers 62 in the first direction z, with the insulating layer 61 sandwiched therebetween. The metal layer 63 contains copper. The metal layer 63 of the first wiring 601 is bonded to the first main surface 121A of the first conductive layer 121 by a second adhesive layer 68. The metal layer 63 of the second wiring 602 is bonded to the second main surface 122A of the second conductive layer 122 by the second adhesive layer 68. The second adhesive layer 68 is made of a material that may or may not be conductive. The second adhesive layer 68 is, for example, solder.

[0050] As shown in FIGS. 18 and 19 , each of the multiple sleeves 64 is bonded to one of the multiple wiring layers 62 by a third adhesive layer 69. The multiple sleeves 64 are made of a conductive material such as metal. Each of the multiple sleeves 64 has a cylindrical shape extending along the first direction z. One end of the multiple sleeves 64 is conductively bonded to one of the multiple wiring layers 62. As shown in FIGS. 10 and 17 , an end surface 641 corresponding to the other end of each of the multiple sleeves 64 is exposed from the top surface 51 of the sealing resin 50, which will be described later. The third adhesive layer 69 is conductive. The third adhesive layer 69 is, for example, solder.

[0051] As shown in FIG. 12 , one of the pair of thermistors 22 is conductively joined to a pair of third wiring layers 623 of the first wiring 601. As shown in FIG. 12 , the other of the pair of thermistors 22 is conductively joined to a pair of third wiring layers 623 of the second wiring 602. The pair of thermistors 22 are, for example, NTC (Negative Temperature Coefficient) thermistors. NTC thermistors have the characteristic of gradually decreasing resistance as temperature increases. The pair of thermistors 22 are used as temperature detection sensors for the semiconductor device B.

[0052] As shown in FIG. 9 , the first signal terminal 161, the second signal terminal 162, the third signal terminal 171, the fourth signal terminal 172, the pair of fifth signal terminals 181, the pair of sixth signal terminals 182, and the seventh signal terminal 19 are made of metal pins extending in the first direction z. These terminals protrude from the top surface 51 of the sealing resin 50, which will be described later. Furthermore, these terminals are individually press-fitted into the multiple sleeves 64 of the pair of control wires 60. As a result, each of these terminals is supported by one of the multiple sleeves 64 and is electrically connected to one of the multiple wiring layers 62.

[0053] 13 and 18 , the first signal terminal 161 is press-fitted into one of the multiple sleeves 64 of the pair of control wires 60 that is joined to the first wiring layer 621 of the first wire 601. As a result, the first signal terminal 161 is supported by the sleeve 64 and is electrically connected to the first wiring layer 621 of the first wire 601. Furthermore, the first signal terminal 161 is electrically connected to the third electrodes 213 of the multiple first elements 21A. A gate voltage for driving the multiple first elements 21A is applied to the first signal terminal 161.

[0054] 13 and 19 , the second signal terminal 162 is press-fitted into one of the multiple sleeves 64 of the pair of control wires 60 that is joined to the first wiring layer 621 of the second wire 602. As a result, the second signal terminal 162 is supported by the sleeve 64 and is electrically connected to the first wiring layer 621 of the second wire 602. Furthermore, the second signal terminal 162 is electrically connected to the third electrodes 213 of the multiple second elements 21B. A gate voltage for driving the multiple second elements 21B is applied to the second signal terminal 162.

[0055] As shown in Fig. 10 , the third signal terminal 171 is located next to the first signal terminal 161 in the third direction y. As shown in Fig. 13 , the third signal terminal 171 is press-fitted into one of the multiple sleeves 64 of the pair of control wires 60 that is joined to the second wiring layer 622 of the first wire 601. As a result, the third signal terminal 171 is supported by the sleeve 64 and is electrically connected to the second wiring layer 622 of the first wire 601. Furthermore, the third signal terminal 171 is electrically connected to the fourth electrodes 214 of the multiple first elements 21A. A voltage corresponding to the maximum current among the currents flowing through the fourth electrodes 214 of the multiple first elements 21A is applied to the third signal terminal 171.

[0056] As shown in Fig. 10 , the fourth signal terminal 172 is located next to the second signal terminal 162 in the third direction y. As shown in Fig. 13 , the fourth signal terminal 172 is press-fitted into one of the multiple sleeves 64 of the pair of control wires 60 that is joined to the second wiring layer 622 of the second wire 602. As a result, the fourth signal terminal 172 is supported by the sleeve 64 and is electrically connected to the second wiring layer 622 of the second wire 602. Furthermore, the fourth signal terminal 172 is electrically connected to the fourth electrodes 214 of the multiple second elements 21B. A voltage corresponding to the maximum current among the currents flowing through the fourth electrodes 214 of the multiple second elements 21B is applied to the fourth signal terminal 172.

[0057] As shown in FIG. 10 , the pair of fifth signal terminals 181 are located on the opposite side of the third signal terminal 171 in the third direction y, with the first signal terminal 161 sandwiched therebetween. The pair of fifth signal terminals 181 are adjacent to each other in the third direction y. As shown in FIG. 13 , the pair of fifth signal terminals 181 are individually press-fitted into a pair of sleeves 64, among the multiple sleeves 64 of the pair of control wires 60, that are joined to the pair of third wiring layers 623 of the first wire 601. As a result, the pair of fifth signal terminals 181 are supported by the pair of sleeves 64 and are electrically connected to the pair of third wiring layers 623 of the first wire 601. Furthermore, the pair of fifth signal terminals 181 are electrically connected to the thermistor 22, among the pair of thermistors 22, that is electrically connected to the pair of third wiring layers 623 of the first wire 601.

[0058] As shown in FIG. 10 , the pair of sixth signal terminals 182 are located on the opposite side of the fourth signal terminal 172 in the third direction y, with the second signal terminal 162 sandwiched therebetween. The pair of sixth signal terminals 182 are adjacent to each other in the third direction y. As shown in FIG. 13 , the pair of sixth signal terminals 182 are individually press-fitted into a pair of sleeves 64, among the multiple sleeves 64 of the pair of control wires 60, that are joined to the pair of third wiring layers 623 of the second wire 602. As a result, the pair of sixth signal terminals 182 are supported by the pair of sleeves 64 and are electrically connected to the pair of third wiring layers 623 of the second wire 602. Furthermore, the pair of sixth signal terminals 182 are electrically connected to the thermistor 22, among the pair of thermistors 22, that is electrically connected to the pair of third wiring layers 623 of the second wire 602.

[0059] As shown in Fig. 10 , the seventh signal terminal 19 is located on the opposite side of the first signal terminal 161 in the third direction y, with the third signal terminal 171 sandwiched therebetween. As shown in Fig. 13 , the seventh signal terminal 19 is press-fitted into one of the multiple sleeves 64 of the pair of control wires 60 that is joined to the fifth wiring layer 625 of the first wire 601. As a result, the seventh signal terminal 19 is supported by the sleeve 64 and is electrically connected to the fifth wiring layer 625 of the first wire 601. Furthermore, the seventh signal terminal 19 is electrically connected to the first conductive layer 121. A voltage equivalent to the DC power input to the first input terminal 13 and the second input terminal 15 is applied to the seventh signal terminal 19.

[0060] As shown in FIG. 13 , the multiple first wires 41 are conductively bonded to the third electrodes 213 of the multiple first elements 21A and the fourth wiring layer 624 of the first wiring 601. As shown in FIG. 13 , the multiple third wires 43 are conductively bonded to the fourth wiring layer 624 of the first wiring 601 and the first wiring layer 621 of the first wiring 601. This allows the first signal terminal 161 to be electrically connected to the third electrodes 213 of the multiple first elements 21A. The composition of the multiple first wires 41 and the multiple third wires 43 includes gold (Au). Alternatively, the composition of the multiple first wires 41 and the multiple third wires 43 may include copper or aluminum.

[0061] 13, the plurality of first wires 41 are conductively joined to the third electrodes 213 of the plurality of second elements 21B and the fourth wiring layer 624 of the second wiring 602. Furthermore, the plurality of third wires 43 are conductively joined to the fourth wiring layer 624 of the second wiring 602 and the first wiring layer 621 of the second wiring 602. As a result, the second signal terminal 162 is electrically connected to the third electrodes 213 of the plurality of second elements 21B.

[0062] As shown in FIG. 13 , the multiple second wires 42 are conductively bonded to the fourth electrodes 214 of the multiple first elements 21A and the second wiring layer 622 of the first wiring 601. As a result, the third signal terminal 171 is electrically connected to the fourth electrodes 214 of the multiple first elements 21A. Furthermore, as shown in FIG. 13 , the multiple second wires 42 are conductively bonded to the fourth electrodes 214 of the multiple second elements 21B and the second wiring layer 622 of the second wiring 602. As a result, the fourth signal terminal 172 is electrically connected to the fourth electrodes 214 of the multiple second elements 21B. The composition of the multiple second wires 42 includes gold. Alternatively, the composition of the multiple second wires 42 may include copper or aluminum.

[0063] 13 , the fourth wire 44 is conductively bonded to the fifth wiring layer 625 of the first wiring 601 and the first main surface 121A of the first conductive layer 121. This allows the seventh signal terminal 19 to be electrically connected to the first conductive layer 121. The composition of the fourth wire 44 includes gold. Alternatively, the composition of the fourth wire 44 may include copper or aluminum.

[0064] As shown in FIGS. 13 and 18 , the first conductive member 31 is conductively bonded to the second electrodes 212 of the plurality of first elements 21A and the second main surface 122A of the second conductive layer 122. This allows the second electrodes 212 of the plurality of first elements 21A to be electrically connected to the second conductive layer 122. The first conductive member 31 contains copper. The first conductive member 31 is a metal clip. As shown in FIG. 13 , the first conductive member 31 has a main body 311, a plurality of first joint portions 312, a plurality of first connecting portions 313, a second joint portion 314, and a second connecting portion 315.

[0065] The main body portion 311 forms a main portion of the first conductive member 31. As shown in Fig. 13 , the main body portion 311 extends in the third direction y. As shown in Fig. 17 , the main body portion 311 straddles between the first conductive layer 121 and the second conductive layer 122.

[0066] 18 , the multiple first bonding portions 312 are individually bonded to the second electrodes 212 of the multiple first elements 21A. Each of the multiple first bonding portions 312 faces the second electrode 212 of one of the multiple first elements 21A.

[0067] 13 , the plurality of first coupling portions 313 are connected to the main body portion 311 and the plurality of first bonding portions 312. The plurality of first coupling portions 313 are spaced apart from one another in the third direction y. As shown in FIG. 17 , when viewed in the third direction y, the plurality of first coupling portions 313 are inclined in a direction away from the first main surface 121A of the first conductive layer 121 as they extend from the plurality of first bonding portions 312 toward the main body portion 311.

[0068] 13 and 17 , the second bonding portion 314 is bonded to the second main surface 122A of the second conductive layer 122. The second bonding portion 314 faces the second main surface 122A. The second bonding portion 314 extends in the third direction y. The dimension of the second bonding portion 314 in the third direction y is equal to the dimension of the main body portion 311 in the third direction y.

[0069] 13 and 17 , the second connecting portion 315 is connected to the main body portion 311 and the second bonding portion 314. When viewed in the third direction y, the second connecting portion 315 is inclined in a direction away from the second main surface 122A of the second conductive layer 122 as it extends from the second bonding portion 314 toward the main body portion 311. The dimension of the second connecting portion 315 in the third direction y is equal to the dimension of the main body portion 311 in the third direction y.

[0070] 17, 18, and 21, the semiconductor device B further includes a first conductive bonding layer 33. The first conductive bonding layer 33 is interposed between the second electrodes 212 of the plurality of first elements 21A and the plurality of first bonding portions 312. The first conductive bonding layer 33 conductively bonds the second electrodes 212 of the plurality of first elements 21A to the plurality of first bonding portions 312. The first conductive bonding layer 33 is, for example, solder. Alternatively, the first conductive bonding layer 33 may include a sintered body of metal particles.

[0071] 17 , the semiconductor device B further includes a second conductive bonding layer 34. The second conductive bonding layer 34 is interposed between the second main surface 122A of the second conductive layer 122 and the second bonding portion 314. The second conductive bonding layer 34 conductively bonds the second main surface 122A and the second bonding portion 314. The second conductive bonding layer 34 is, for example, solder. Alternatively, the second conductive bonding layer 34 may include a sintered body of metal particles.

[0072] As shown in FIGS. 12 and 19 , the second conductive member 32 is conductively joined to the second electrodes 212 of the plurality of second elements 21B and the covering portion 15A of the second input terminal 15. This electrically connects the second electrodes 212 of the plurality of second elements 21B to the second input terminal 15. The second conductive member 32 contains copper. The second conductive member 32 is a metal clip. As shown in FIG. 12 , the second conductive member 32 has a pair of main body portions 321, a plurality of third joint portions 322, a plurality of third connecting portions 323, a pair of fourth joint portions 324, a pair of fourth connecting portions 325, a plurality of intermediate portions 326, and a plurality of cross beam portions 327.

[0073] As shown in Fig. 12 , the pair of main bodies 321 are spaced apart from each other in the third direction y. The pair of main bodies 321 extend in the second direction x. As shown in Fig. 16 , the pair of main bodies 321 are arranged parallel to the first main surface 121A of the first conductive layer 121 and the second main surface 122A of the second conductive layer 122. The pair of main bodies 321 are spaced apart from the first main surface 121A and the second main surface 122A more than the main body 311 of the first conductive member 31.

[0074] 12 , the intermediate portions 326 are spaced apart from one another in the third direction y and are located between the pair of main body portions 321 in the third direction y. The intermediate portions 326 extend in the second direction x. The dimension of each of the intermediate portions 326 in the second direction x is smaller than the dimension of each of the pair of main body portions 321 in the second direction x.

[0075] 19 , the multiple third bonding portions 322 are individually bonded to the second electrodes 212 of the multiple second elements 21B. Each of the multiple third bonding portions 322 faces the second electrode 212 of one of the multiple second elements 21B.

[0076] 12 and 20 , the multiple third connecting portions 323 are connected to both sides of the multiple third joint portions 322 in the third direction y. Furthermore, the multiple third connecting portions 323 are connected to either the pair of main body portions 321 or the multiple intermediate portions 326. When viewed in the second direction x, each of the multiple third connecting portions 323 is inclined in a direction away from the second main surface 122A of the second conductive layer 122 as it moves from either one of the multiple third joint portions 322 to either the pair of main body portions 321 or the multiple intermediate portions 326.

[0077] 12 and 16, the pair of fourth joint portions 324 are joined to the covering portion 15A of the second input terminal 15. The pair of fourth joint portions 324 face the covering portion 15A.

[0078] 12 and 16 , the pair of fourth connecting portions 325 are connected to the pair of main body portions 321 and the pair of fourth joint portions 324. When viewed in the third direction y, the pair of fourth connecting portions 325 are inclined in a direction away from the first main surface 121A of the first conductive layer 121 as they extend from the pair of fourth joint portions 324 toward the pair of main body portions 321.

[0079] As shown in FIGS. 12 and 21 , the multiple cross beam portions 327 are arranged along the third direction y. As viewed in the first direction z, the multiple cross beam portions 327 include regions that individually overlap the multiple first joint portions 312 of the first conductive member 31. Of the multiple cross beam portions 327, the cross beam portion 327 located at the center in the third direction y is connected to the multiple intermediate portions 326 on both sides in the third direction y. Of the multiple cross beam portions 327, the remaining two cross beam portions 327 are connected to one of the pair of main body portions 321 and one of the multiple intermediate portions 326 on both sides in the third direction y. As viewed in the second direction x, the multiple cross beam portions 327 are convex in the first direction z toward the first main surface 121A of the first conductive layer 121.

[0080] 17, 19, and 20, the semiconductor device B further includes a third conductive bonding layer 35. The third conductive bonding layer 35 is interposed between the second electrodes 212 of the plurality of second elements 21B and the plurality of third bonding portions 322. The third conductive bonding layer 35 conductively bonds the second electrodes 212 of the plurality of second elements 21B to the plurality of third bonding portions 322. The third conductive bonding layer 35 is, for example, solder. Alternatively, the third conductive bonding layer 35 may include a sintered body of metal particles.

[0081] 16 , the semiconductor device B further includes a fourth conductive bonding layer 36. The fourth conductive bonding layer 36 is interposed between the covering portion 15A of the second input terminal 15 and the pair of fourth joint portions 324. The fourth conductive bonding layer 36 conductively bonds the covering portion 15A and the pair of fourth joint portions 324. The fourth conductive bonding layer 36 is, for example, solder. Alternatively, the fourth conductive bonding layer 36 may include a sintered body of metal particles.

[0082] As shown in FIGS. 16 , 17 , 20 , and 21 , the sealing resin 50 covers the first conductive layer 121, the second conductive layer 122, the semiconductor elements 21, the first conductive members 31, and the second conductive members 32. The sealing resin 50 also covers a portion of each of the substrate 11, the first input terminal 13, the output terminal 14, and the second input terminal 15. The sealing resin 50 has electrical insulation properties. The sealing resin 50 is made of a material containing, for example, black epoxy resin. As shown in FIGS. 10 and 14 to 17 , the sealing resin 50 has a top surface 51, a bottom surface 52, a pair of first side surfaces 53, a pair of second side surfaces 54, and a pair of recesses 55.

[0083] 16 and 17 , top surface 51 faces the same side as first main surface 121A of first conductive layer 121 in first direction z. As shown in Fig. 16 and 17 , bottom surface 52 faces the opposite side from top surface 51 in first direction z. As shown in Fig. 15 , heat dissipation layer 113 of base material 11 is exposed from bottom surface 52.

[0084] 10 and 14 , the pair of first side surfaces 53 are spaced apart from each other in the second direction x. The pair of first side surfaces 53 face the second direction x and extend in the third direction y. The pair of first side surfaces 53 are connected to the top surface 51. An exposed portion 13B of the first input terminal 13 and an exposed portion 15B of the second input terminal 15 are exposed from one of the pair of first side surfaces 53. An exposed portion 14B of the output terminal 14 is exposed from the other of the pair of first side surfaces 53.

[0085] 10 and 15 , the pair of second side surfaces 54 are spaced apart from each other in the third direction y. The pair of second side surfaces 54 face opposite each other in the third direction y and extend in the second direction x. The pair of second side surfaces 54 are connected to the top surface 51 and the bottom surface 52.

[0086] 10 and 15 , the pair of recesses 55 are recessed in the second direction x from the first side surfaces 53 on which the exposed portion 13B of the first input terminal 13 and the exposed portion 15B of the second input terminal 15 are exposed. The pair of recesses 55 extend from the top surface 51 to the bottom surface 52 in the first direction z. The pair of recesses 55 are located on both sides of the first input terminal 13 in the third direction y.

[0087] First embodiment (cooling structure for semiconductor device): Next, a cooling structure C10 (hereinafter referred to as "cooling structure C10") according to a first embodiment of the present disclosure will be described with reference to Figures 22 and 23. The cooling structure C10 includes a cooler A10, a semiconductor device B, and a mounting member 88. The cooling structure C10 constitutes, for example, a part of an inverter device for driving a three-phase AC motor. Here, in Figure 22, line XXIII-XXIII is indicated by a dashed line.

[0088] In the cooling structure C10, the semiconductor device B is attached to the main surface 71A of the housing 70 of the cooler A10, as shown in Figures 22 and 23. The semiconductor device B closes the opening 711 of the housing 70. More specifically, as shown in Figure 23, the heat dissipation layer 113 of the base material 11 of the semiconductor device B closes the opening 711. The bottom surface 52 of the sealing resin 50 of the semiconductor device B contacts the main surface 71A.

[0089] As shown in FIGS. 22 and 23 , the mounting member 88 holds the semiconductor device B in the housing 70 of the cooler A10. The mounting member 88 is made of a material containing metal. The mounting member 88 contacts the top surface 51 of the sealing resin 50 of the semiconductor device B and straddles the top surface 51. The mounting member 88 is, for example, a leaf spring. The mounting member 88 is located between one of the first signal terminals 161 and the second signal terminal 162 of the semiconductor device B in the second direction x. The mounting member 88 is attached to the housing 70 on both sides in the third direction y by fastening members 89. The fastening members 89 are, for example, bolts.

[0090] Next, the effects of the cooler A10 and the cooling structure C10 will be described.

[0091] The cooler A10 includes a housing 70 and a partition wall 81. The housing 70 has an opening 711 located on one side in the first direction z, an inner space 73 connected to the opening 711, and a bottom 72 located on the opposite side of the inner space 73 from the opening 711. The inner space 73 includes a first storage section 731 and a second storage section 732 separated by the partition wall 81. The partition wall 81 overlaps the opening 711 as viewed in the first direction z and has an overflow section 811 that is farthest from the bottom 72 of the housing 70. The overflow section 811 is located between the bottom 72 and the opening 711.

[0092] With this configuration, as the refrigerant continues to flow into the first storage portion 731 via the inflow path 74, the liquid level of the refrigerant rises toward the overflow portion 811. Thereafter, when the liquid level rises further above the overflow portion 811, the refrigerant passes over the overflow portion 811 and flows down into the second storage portion 732. This suppresses interference of the inner space 73 with the direction of the refrigerant flow. Furthermore, because the potential head of the refrigerant increases from the inflow path 74 to the overflow portion 811, a decrease in the total amount of energy of the refrigerant flow in the first storage portion 731 is suppressed. This makes it easier for the refrigerant to be distributed throughout the entire object to be cooled in the cooler A10.

[0093] In the cooling structure C10, the semiconductor device B blocks the opening 711. Furthermore, in the cooler A10, the overflow portion 811 is spaced from the opening 711 in the first direction z. With this configuration, a gap is defined between the overflow portion 811 and the semiconductor device B in the first direction z in the cooling structure C10. As a result, the refrigerant flows down through the gap, allowing the refrigerant to overcome the overflow portion 811 (see the arrows in FIG. 23 ). In the cooling structure C10, the refrigerant flowing down through the gap contacts the semiconductor device B, thereby cooling the semiconductor device B. The flow direction of the refrigerant contacting the semiconductor device B is perpendicular to the first direction z. Therefore, in the cooling structure C10, the semiconductor device B is less likely to interfere with the refrigerant flow. Therefore, with the above configuration, the cooler A10 and the cooling structure C10 can improve cooling efficiency while suppressing energy loss in the refrigerant flow.

[0094] The partition wall 81 includes a first partition wall 81A and a second partition wall 81B that overlap the opening 711 of the housing 70 as viewed in the first direction z and are spaced apart from each other in the second direction x. The first storage section 731 is located between the first partition wall 81A and the second partition wall 81B. As viewed in the first direction z, the first storage section 731 overlaps with the center C of the opening 711. With this configuration, the flow direction of the coolant that overflows the overflow section 811 of the partition wall 81 is directed from the center C to both sides in the second direction x. This reduces bias in the flow of the coolant that comes into contact with the semiconductor device B.

[0095] In the above case, each of the first partition 81A and the second partition 81B extends in the third direction y. With this configuration, when the cooling structure C10 cools a semiconductor device B including a plurality of semiconductor elements 21 arranged in the third direction y, it is possible to reduce uneven heat distribution in the semiconductor device B caused by the plurality of semiconductor elements 21.

[0096] The inlet channel 74 and the outlet channel 75 are provided in the bottom 72. Each of the inlet channel 74 and the outlet channel 75 penetrates the bottom 72 in the first direction z. This configuration makes it possible to increase the head of the refrigerant flowing into the first storage portion 731 while suppressing an increase in the dimension of the cooler A10 in a direction perpendicular to the first direction z. This further suppresses a decrease in the total amount of energy of the refrigerant flow in the first storage portion 731.

[0097] The main body 71 and the partition wall 81 of the housing 70 are made of a material containing resin. The partition wall 81 is integrated with the main body 71. This configuration makes it possible to reduce the weight of the cooler A10 while improving the rigidity of the cooler A10.

[0098] Second embodiment (cooler): A cooler A20 according to a second embodiment of the present disclosure will be described with reference to Figures 24 to 28. In these figures, elements that are the same as or similar to those of the cooler A10 described above are designated by the same reference numerals, and duplicated descriptions will be omitted.

[0099] The cooler A20 differs from the cooler A10 in that it further includes a cover member 82.

[0100] As shown in FIGS. 24 to 27 , the lid member 82 closes the opening 711 of the housing 70. The main body 71 of the housing 70 has a plurality of mounting holes 712 recessed from the main surface 71A. The lid member 82 has a plurality of through holes 824 penetrating the lid member 82 in the first direction z. When viewed in the first direction z, the plurality of through holes 824 individually overlap the plurality of mounting holes 712. The lid member 82 is attached to the main body 71 by inserting fastening members 825 into each of the plurality of through holes 824 and each of the plurality of mounting holes 712. The fastening members 825 are, for example, bolts. The lid member 82 is made of a material containing metal. The thermal conductivity of the lid member 82 is higher than the thermal conductivity of each of the main body 71 and the partition wall 81.

[0101] 26 and 27 , the cover member 82 has a base surface 821 facing the opening 711 of the housing 70. The base surface 821 is spaced apart from the overflow portion 811 of the partition wall 81. Therefore, in the cooler A20, a gap is provided between the overflow portion 811 and the base surface 821.

[0102] 26 to 28 , the cover member 82 has a recessed portion 822 that is recessed in the first direction z. The recessed portion 822 includes a portion defined by the base surface 821. Therefore, the recessed portion 822 faces the opening 711 of the housing 70.

[0103] 26 to 28 , the cover member 82 has a heat dissipation portion 823 that protrudes from a base surface 821. The heat dissipation portion 823 is housed in a recess 822. In the cooler A20, the heat dissipation portion 823 is spaced apart from the overflow portion 811 of the partition wall 81.

[0104] 28 , the heat dissipation unit 823 includes a plurality of fins each extending in the second direction x. The fins are arranged along the third direction y. Therefore, as viewed in the first direction z, each of the fins is perpendicular to each of the first partition 81A and the second partition 81B of the partition 81. Alternatively, the heat dissipation unit 823 may include a plurality of pins spaced apart from each other in a direction perpendicular to the first direction z.

[0105] Second embodiment (cooling structure for semiconductor device): Next, a cooling structure C20 according to a second embodiment of the present disclosure (hereinafter referred to as "cooling structure C20") will be described with reference to Figures 29 and 30. In these figures, elements that are the same as or similar to the cooling structure C10 described above are designated by the same reference numerals, and duplicated descriptions will be omitted. Here, in Figure 29, the XXX-XXX line is indicated by a dashed line.

[0106] The cooling structure C20 includes the cooler A20, the semiconductor device B, and an attachment member 88. In the cooling structure C20, the semiconductor device B is attached to the lid member 82 of the cooler A20, as shown in Figures 29 and 30 . The heat dissipation layer 113 of the base 11 of the semiconductor device B and the bottom surface 52 of the sealing resin 50 of the semiconductor device B are in contact with the lid member 82. When viewed in the first direction z, the base 11 of the semiconductor device B overlaps the opening 711 of the housing 70.

[0107] As shown in FIG. 29, the mounting member 88 is attached to the cover member 82 by fastening members 89 on both sides in the third direction y.

[0108] Next, the effects of the cooler A20 and the cooling structure C20 will be described.

[0109] The cooler A20 includes a housing 70 and a partition wall 81. The housing 70 has an opening 711 located on one side in the first direction z, an inner space 73 connected to the opening 711, and a bottom 72 located on the opposite side of the inner space 73 from the opening 711. The inner space 73 includes a first storage section 731 and a second storage section 732 separated by the partition wall 81. The partition wall 81 has an overflow section 811 that overlaps the opening 711 as viewed in the first direction z and is farthest from the bottom 72 of the housing 70. The overflow section 811 is located between the bottom 72 and the opening 711. With this configuration, energy loss in the refrigerant flow is suppressed in the cooler A20 as well, making it easier for the refrigerant to be distributed throughout the entire object to be cooled.

[0110] The cooler A20 has a base surface 821 facing the opening 711 and further includes a lid member 82 that closes the opening 711. The overflow portion 811 is spaced apart from the base surface 821. This configuration allows a gap to be formed between the overflow portion 811 and the base surface 821 in the cooler A20. This allows the refrigerant to flow downward through the gap, allowing the refrigerant to overcome the overflow portion 811 (see the arrows in FIG. 30 ). Furthermore, in the cooling structure C20, the semiconductor device B is attached to the lid member 82. As viewed in the first direction z, the semiconductor device B overlaps the opening 711. This configuration allows the refrigerant to come into contact with the lid member 82 in the cooling structure C20, thereby cooling the semiconductor device B via the lid member 82. Therefore, the semiconductor device B does not come into contact with the refrigerant, and therefore the semiconductor device B does not interfere with the flow of the refrigerant in the cooling structure C20. Therefore, with the above configuration, it is possible to improve the cooling efficiency while suppressing the energy loss in the flow of the refrigerant in the cooler A20 and the cooling structure C20 as well.

[0111] In the cooler A20, the cover member 82 is provided with a recessed portion 822 that is recessed in the first direction z and includes a portion defined by a base surface 821. The cover member 82 has a heat dissipation portion 823 that protrudes from the base surface 821. The heat dissipation portion 823 is housed in the recessed portion 822. With this configuration, a gap necessary for the refrigerant to flow downward is secured between the overflow portion 811 of the partition wall 81 and the base surface 821, and the refrigerant comes into contact with the heat dissipation portion 823, thereby effectively improving the cooling efficiency of the cooler A20.

[0112] The heat dissipation portion 823 of the cover member 82 includes a plurality of fins each extending in the second direction x. The plurality of fins are arranged along the third direction y. With this configuration, when the refrigerant passes over the overflow portion 811 of the partition wall 81, interference of the heat dissipation portion 823 with the direction of the refrigerant flow is suppressed. Furthermore, since the contact area of ​​the refrigerant with the heat dissipation portion 823 is increased, the cooling efficiency of the cooler A20 can be further improved.

[0113] The cooler A30 has the same configuration as the cooler A10, and thus exhibits the same effects as the cooler A10.

[0114] Third Embodiment (Cooler): A cooler A30 according to a third embodiment of the present disclosure will be described with reference to Figures 31 to 33. In these figures, elements that are the same as or similar to those of the cooler A10 and the cooler A20 described above are designated by the same reference numerals, and duplicated descriptions will be omitted. Here, in Figure 31, the cover member 82 is shown in perspective for ease of understanding. In Figure 31, the transparent cover member 82 is shown by imaginary lines.

[0115] In the cooler A30, the configuration of the partition wall 81 and the main body 71 of the housing 70 differs from that of the cooler A20.

[0116] 32 and 33 , in the first direction z, the position of the overflow portion 811 of the partition wall 81 is equal to the position of the opening 711 of the housing 70. Therefore, the overflow portion 811 is flush with the main surface 71A of the housing 70.

[0117] 31 to 33 , a groove 713 recessed from a main surface 71A is provided in the main body 71 of the housing 70. The groove 713 forms a part of an opening 711 of the housing 70. The portion of the partition wall 81 exposed from the opening 711 is surrounded by the groove 713.

[0118] 32 and 33 , the heat dissipation portion 823 of the cover member 82 is in contact with the overflow portion 811 of the partition wall 81. However, the base surface 821 of the cover member 82 is spaced apart from the overflow portion 811. Therefore, in the cooler A30 as well, a gap is provided between the overflow portion 811 and the base surface 821.

[0119] Next, the function and effect of the cooler A30 will be described.

[0120] The cooler A30 includes a housing 70 and a partition wall 81. The housing 70 has an opening 711 located on one side in the first direction z, an inner space 73 connected to the opening 711, and a bottom 72 located on the opposite side of the inner space 73 from the opening 711. The inner space 73 includes a first storage section 731 and a second storage section 732 separated by the partition wall 81. The partition wall 81 has an overflow section 811 that overlaps the opening 711 as viewed in the first direction z and is farthest from the bottom 72 of the housing 70. The overflow section 811 is located between the bottom 72 and the opening 711. With this configuration, energy loss in the refrigerant flow is suppressed in the cooler A30 as well, making it easier for the refrigerant to be distributed throughout the entire object to be cooled.

[0121] The cooler A30 has a base surface 821 facing the opening 711, and further includes a lid member 82 that closes the opening 711. The overflow portion 811 is spaced apart from the base surface 821. With this configuration, a gap is also formed between the overflow portion 811 and the base surface 821 in the cooler A30. This allows the refrigerant to flow downward into the gap, allowing the refrigerant to come into contact with the lid member 82 and overcome the overflow portion 811. Therefore, with the above configuration, the cooler A30 can also improve cooling efficiency while suppressing energy loss in the refrigerant flow.

[0122] In the cooler A30, the heat dissipation portion 823 of the cover member 82 is in contact with the overflow portion 811 of the partition wall 81. With this configuration, the refrigerant that flows over the overflow portion 811 can come into contact with a wider area of ​​the heat dissipation portion 823. Therefore, the cooling efficiency of the cooler A30 can be further improved.

[0123] The cooler A30 has the same configuration as the cooler A10, and thus has the same effects as the cooler A10. Furthermore, the cooling structure C20 described above may be equipped with the cooler A30 instead of the cooler A20.

[0124] Fourth embodiment (cooler): A cooler A40 according to a fourth embodiment of the present disclosure will be described with reference to Figures 34 to 37. In these figures, elements that are the same as or similar to those of the cooler A10 described above are designated by the same reference numerals, and duplicated descriptions will be omitted.

[0125] In the cooler A40, the configuration of the partition wall 81 and the inner space 73 of the housing 70 differs from that of the cooler A10.

[0126] 34 and 35 , the partition wall 81 includes an annular portion 812 and a cover portion 813 instead of the first partition wall 81A, the second partition wall 81B, the third partition wall 81C, the fourth partition wall 81D, and the fifth partition wall 81E. As viewed in the first direction z, the annular portion 812 surrounds the center C of the opening 711 of the housing 70. In the cooler A40, the annular portion 812 includes an overflow portion 811.

[0127] 34 and 35, the cover portion 813 connects the annular portion 812 and the main body portion 71 of the housing 70. As shown in Figures 35 to 37, the cover portion 813 is spaced apart from the overflow portion 811 in the first direction z.

[0128] 34 , when viewed in the first direction z, the second storage portion 732 surrounds the first storage portion 731. When viewed in the first direction z, the second storage portion 732 overlaps the cover portion 813. A portion of the first storage portion 731 is surrounded by the bottom portion 72 of the housing 70 and the cover portion 813.

[0129] Next, the function and effect of the cooler A40 will be described.

[0130] The cooler A40 includes a housing 70 and a partition wall 81. The housing 70 has an opening 711 located on one side in the first direction z, an inner space 73 connected to the opening 711, and a bottom 72 located on the opposite side of the inner space 73 from the opening 711. The inner space 73 includes a first storage section 731 and a second storage section 732 separated by the partition wall 81. The partition wall 81 has an overflow section 811 that overlaps the opening 711 as viewed in the first direction z and is farthest from the bottom 72 of the housing 70. The overflow section 811 is located between the bottom 72 and the opening 711. With this configuration, energy loss in the refrigerant flow is suppressed in the cooler A40 as well, making it easier for the refrigerant to be distributed throughout the entire object to be cooled.

[0131] In the cooler A40, the overflow portion 811 is spaced apart from the opening 711 in the first direction z. By adopting this configuration, even when the cooler A10 in the cooling structure C10 described above is replaced with the cooler A40, a gap is set between the overflow portion 811 and the semiconductor device B in the first direction z. This allows the refrigerant to flow downward into the gap, allowing the refrigerant to overcome the overflow portion 811. Therefore, with the above configuration, even in the cooler A40, it is possible to improve the cooling efficiency while suppressing energy loss in the refrigerant flow.

[0132] In the cooler A40, the second storage portion 732 surrounds the first storage portion 731 as viewed in the first direction z. Furthermore, as viewed in the first direction z, the first storage portion 731 overlaps with the center C of the opening 711 of the housing 70. With this configuration, the flow of the coolant that overcomes the overflow portion 811 of the partition wall 81 becomes radial as viewed in the first direction z. This further reduces the bias in the flow of the coolant that comes into contact with the semiconductor device B.

[0133] In the cooler A40, the cover portion 813 of the partition wall 81 is spaced apart from the overflow portion 811 of the partition wall 81 in the first direction z. By adopting this configuration, the second storage portion 732 can surround the first storage portion 731 as viewed in the first direction z.

[0134] The cooler A40 has the same configuration as the cooler A10, and thus provides the same operational effects as the cooler A10. As described above, the cooling structure C10 may be equipped with the cooler A40 instead of the cooler A10. Furthermore, the cooler A40 may be configured to include a cover member 82 similar to that of the cooler A20 described above.

[0135] Third Embodiment (Cooling Structure for Semiconductor Device): Next, a cooling structure C30 according to a third embodiment of the present disclosure (hereinafter referred to as "cooling structure C30") will be described with reference to Fig. 38. In these figures, elements that are the same as or similar to the cooling structures C10 and C20 described above are designated by the same reference numerals, and duplicated descriptions will be omitted.

[0136] The cooling structure C30 includes a cooler A50, a plurality of semiconductor devices B, a plurality of mounting members 88, a branch flow path 76, and a merging flow path 77. The cooler A50 is configured by arranging a plurality of coolers A20 along the third direction y and connecting their respective housings 70. Alternatively, the cooler A50 may be configured by arranging any one of a plurality of coolers A10, a plurality of coolers A30, and a plurality of coolers A40 along the third direction y and connecting their respective housings 70.

[0137] 38, the cooler A50 has a plurality of hollow portions 73 arranged in a direction perpendicular to the first direction z. Each of the plurality of hollow portions 73 is recessed in the first direction z.

[0138] 38 , the semiconductor devices B are individually attached to the cover members 82 of the cooler A50 by the attachment members 88. When viewed in the first direction z, the semiconductor devices B individually overlap the hollow portions 73.

[0139] A plurality of inflow channels 74 and a plurality of outflow channels 75 are provided in a bottom 72 of a housing 70 of the cooler A50. Each of the plurality of inflow channels 74 and each of the plurality of inflow channels 74 extend from the bottom 72 to the outside. The plurality of inflow channels 74 are individually connected to a plurality of internal spaces 73. The plurality of outflow channels 75 are individually connected to a plurality of internal spaces 73.

[0140] 38, the branch flow path 76 is connected to the inlet portion 741 of each of the plurality of inlet paths 74. The merged flow path 77 is connected to the outlet portion 751 of each of the plurality of outlet paths 75.

[0141] The arrows in Figure 38 indicate the direction of refrigerant flow in the cooling structure C30. The refrigerant supplied from the outside to the branch channel 76 flows individually into the multiple internal spaces 73 via the multiple inflow channels 74. The refrigerant that has individually flowed into the multiple internal spaces 73 then flows downward into the merging channel 77 via the multiple outflow channels 75. The refrigerant that has flowed downward into the merging channel 77 is discharged to the outside. Therefore, in the cooler A50, each of the multiple outflow channels 75 is set as a different system from any of the multiple inflow channels 74. Therefore, in the cooling structure C30, the refrigerant flowing through each of the multiple outflow channels 75 does not flow downward through any of the multiple inflow channels 74 until it is discharged to the outside.

[0142] Next, the function and effect of the cooling structure C30 will be described.

[0143] The cooling structure C30 includes a cooler A50 having multiple internal cavities 73 and multiple semiconductor devices B attached to the cooler A50. When viewed in the first direction z, the multiple semiconductor devices B are individually overlapped with the multiple internal cavities 73. The cooler A50 is provided with multiple inlet channels 74 and multiple outlet channels 75, each configured as a separate system from the multiple inlet channels 74. The multiple inlet channels 74 are individually connected to the multiple internal cavities 73. The multiple outlet channels 75 are individually connected to the multiple internal cavities 73. This configuration allows the refrigerant flow systems in the multiple internal cavities 73 to be parallel. As a result, the refrigerant flowing into each of the multiple internal cavities 73 is relatively low in temperature and has a uniform temperature. This improves the cooling efficiency of the multiple semiconductor devices B. Furthermore, compared to when the refrigerant flow systems in the multiple internal cavities 73 are serially connected, the number of times the refrigerant's flow cross-section suddenly expands is reduced, thereby suppressing energy loss in the refrigerant flow. Therefore, according to this configuration, even in the cooling structure C30, it is possible to improve the cooling efficiency while suppressing the energy loss in the flow of the refrigerant.

[0144] The present disclosure is not limited to the above-described embodiment, and the specific configuration of each part of the present disclosure can be freely modified in various ways.

[0145] The present disclosure includes embodiments described in the following supplementary notes. Supplementary note 1. A cooler comprising: a housing having an opening located on one side in a first direction, an internal space connected to the opening, and a bottom located on the opposite side of the internal space from the opening and defining a part of the internal space; and a partition wall rising from the bottom in the first direction and housed in the internal space, wherein the housing is provided with an inlet channel and an outlet channel each connected to the internal space, the internal space including a first reservoir and a second reservoir separated by the partition wall, the first reservoir connected to the inlet channel, and the second reservoir connected to the outlet channel, the partition wall having an overflow portion overlapping the opening as viewed in the first direction and farthest from the bottom, the overflow portion being located between the bottom and the opening. Supplementary note 2. The cooler according to Supplementary note 1, wherein the overflow portion is farthest from the opening in the first direction. Supplementary note 3. The cooler according to Appendix 1 or 2, further comprising a base surface facing the opening and a lid member closing the opening, wherein the overflow portion is spaced from the base surface. Appendix 4. The cooler according to Appendix 2 or 3, wherein the second storage portion surrounds the first storage portion when viewed in the first direction. Appendix 5. The cooler according to Appendix 3, wherein the partition wall includes a first wall and a second wall that overlap the opening when viewed in the first direction and are spaced from each other in a second direction perpendicular to the first direction, and either the first storage portion or the second storage portion is located between the first wall and the second wall. Appendix 6. The cooler according to Appendix 5, wherein each of the first wall and the second wall extends in a third direction perpendicular to the first direction and the second direction. Appendix 7. The cooler according to Appendix 6, wherein the first storage portion is located between the first wall and the second wall. Appendix 8. The cooler according to claim 7, wherein the first storage portion overlaps the center of the opening when viewed in the first direction. The cooler according to any one of claims 2 to 8, wherein the inlet channel and the outlet channel are provided in the bottom portion, and each of the inlet channel and the outlet channel penetrates the bottom portion in the first direction.Appendix 10. The cooler according to any one of Appendixes 2 to 9, wherein the housing has a main body including the opening and defining a portion of the internal space, and the bottom is attached to the main body. Appendix 11. The cooler according to any one of Appendixes 2 to 10, wherein the main body and the partition are made of a material including a resin. Appendix 12. The cooler according to Appendix 11, wherein the partition is integral with the main body. Appendix 13. The cooler according to any one of Appendixes 6 to 8, wherein the lid member is provided with a recess that is recessed in the first direction and includes a portion defined by the base surface, and the lid member has a heat dissipation portion that protrudes from the base surface, and the heat dissipation portion is housed in the recess. Appendix 14. The cooler according to Appendix 13, wherein the heat dissipation portion includes a plurality of fins that each extend in the second direction, and the plurality of fins are arranged along the third direction. Appendix 15. A cooling structure for a semiconductor device, comprising: the cooler according to Appendix 2; and a semiconductor device attached to the cooler, wherein the semiconductor device is attached to the housing, and the semiconductor device covers the opening. Appendix 16. A cooling structure for a semiconductor device according to Appendix 15, wherein the semiconductor device comprises a base, a conductive layer supported by the base, and a semiconductor element located on the opposite side of the conductive layer from the base and bonded to the conductive layer, and the base covers the opening. Appendix 17. A cooling structure for a semiconductor device, comprising: the cooler according to Appendix 3; and a semiconductor device attached to the cooler, wherein the semiconductor device is attached to the lid member, and when viewed in the first direction, the semiconductor device overlaps the opening.Supplementary Note 18. A cooling structure for a semiconductor device, comprising: a cooler having a plurality of internal spaces each recessed in a first direction and arranged in a direction perpendicular to the first direction; and a plurality of semiconductor devices attached to the cooler, wherein as viewed in the first direction, the plurality of semiconductor devices individually overlap the plurality of internal spaces, the cooler is provided with a plurality of inflow paths and a plurality of outflow paths set as a system different from the plurality of inflow paths, the plurality of inflow paths individually connected to the plurality of internal spaces, and the plurality of outflow paths individually connected to the plurality of internal spaces.

[0146] A10, A20, A30, A40, A50: cooler B: semiconductor device C10, C20, C30: cooling structure 11: base material 111: insulating layer 112: intermediate layer 113: heat dissipation layer 121: first conductive layer 121A: first main surface 121B: first back surface 122: second support layer 122A: second main surface 122B: second back surface 123: first adhesive layer 13: first input terminal 13A: covering portion 13B: exposed portion 14: output terminal 14A: covering portion 14B: exposed portion 15: second input terminal 15A: covering portion 15B: exposed portion 161: first signal terminal 162: second signal terminal 171: third signal terminal 172: fourth signal terminal 181: fifth signal terminal 182: Sixth signal terminal 19: Seventh signal terminal 21: Semiconductor element 21A: First element 21B: Second element 211: First electrode 212: Second electrode 213: Third electrode 214: Fourth electrode 22: Thermistor 23: Conductive bonding layer 31: First conductive member 311: Main body portion 312: First bonding portion 313: First connecting portion 314: Second bonding portion 315: Second connecting portion 32: Second conductive member 321: Main body portion 322: Third bonding portion 323: Third connecting portion 324: Fourth bonding portion 325: Fourth connecting portion 326: Middle portion 327: Horizontal beam portion 33: First conductive bonding layer 34: Second conductive bonding layer 35: Third conductive bonding layer 36: Fourth conductive bonding layer 41: First wire 42: Second wire 43: Third wire 44: Fourth wire 50: Sealing resin 51: Top surface 52: Bottom surface 53: First side surface 54: Second side surface 55: Recess 60: Control wiring 601: First wiring 602: Second wiring 61: Insulating layer 62: Wiring layer 621: First wiring layer 622: Second wiring layer 623: Third wiring layer 624: Fourth wiring layer 625: Fifth wiring layer 63: Metal layer 64: Sleeve 641: End surface 68: Second adhesive layer 69: Third adhesive layer 70: Housing 71: Main body 71A: Main surface 711: Opening 712: Mounting hole 713: Groove 72: Bottom 72A: Back surface 73: Inner space 731: First storage section 732: Second storage section 74: Inflow channel 741: Inflow section 75: Outflow channel 751: Outflow section 76: Branch channel 77: Merging channel81: Partition wall 81A: First partition wall 81B: Second partition wall 81C: Third partition wall 81D: Fourth partition wall 81E: Fifth partition wall 811: Overflow portion 812: Annular portion 813: Cover portion 82: Lid member 821: Base surface 822: Recessed portion 823: Heat dissipation portion 824: Through hole 825: Fastening member 88: Mounting member 89: Fastening member z: First direction x: Second direction y: Third direction

Claims

1. a housing having an opening located on one side in a first direction, an internal space connected to the opening, and a bottom located on the opposite side of the internal space from the opening and defining a part of the internal space; a partition wall rising from the bottom in the first direction and accommodated in the inner space, the housing is provided with an inlet passage and an outlet passage each connected to the internal space, the inner space includes a first storage section and a second storage section partitioned by the partition wall, The first storage portion is connected to the inflow path, The second storage portion is connected to the outflow path, The partition wall has an overflow portion that overlaps the opening when viewed in the first direction and is furthest from the bottom portion, The overflow portion is located between the bottom and the opening.

2. The cooler of claim 1 , wherein the overflow portion is spaced apart from the opening in the first direction.

3. a cover member having a base surface facing the opening and closing the opening, The cooler of claim 1 , wherein the overflow portion is spaced from the base surface.

4. The cooler according to claim 2 , wherein the second storage portion surrounds the first storage portion when viewed in the first direction.

5. the partition wall includes a first wall and a second wall that overlap the opening when viewed in the first direction and are spaced apart from each other in a second direction perpendicular to the first direction, The cooler of claim 3 , wherein either the first reservoir or the second reservoir is located between the first wall and the second wall.

6. The cooler of claim 5 , wherein each of the first wall and the second wall extends in a third direction perpendicular to the first direction and the second direction.

7. The cooling device of claim 6 , wherein the first reservoir is located between the first wall and the second wall.

8. The cooler according to claim 7 , wherein the first storage portion overlaps a center of the opening portion when viewed in the first direction.

9. The inlet and outlet channels are provided in the bottom portion, The cooler according to claim 2 , wherein each of the inlet passage and the outlet passage penetrates the bottom in the first direction.

10. the housing has a main body portion that includes the opening and defines a portion of the internal space; The cooler according to claim 2 , wherein the bottom portion is attached to the body portion.

11. The cooler according to claim 10 , wherein the main body and the partition are made of a material containing resin.

12. The cooler of claim 11 , wherein the partition is integral with the body portion.

13. the cover member is provided with a recessed portion that is recessed in the first direction and includes a portion defined by the base surface, the cover member has a heat dissipation portion protruding from the base surface, The cooler according to claim 6 , wherein the heat dissipation portion is housed in the recess.

14. the heat dissipation portion includes a plurality of fins each extending in the second direction, The cooler according to claim 13 , wherein the plurality of fins are arranged along the third direction.

15. A cooler according to claim 2; a semiconductor device attached to the cooler, the semiconductor device is attached to the housing, The semiconductor device covers the opening.

16. The semiconductor device includes a base material, a conductive layer supported by the base material, and a semiconductor element located on the opposite side of the conductive layer from the base material and bonded to the conductive layer; The cooling structure for a semiconductor device according to claim 15 , wherein the base material covers the opening.

17. A cooler according to claim 3; a semiconductor device attached to the cooler, the semiconductor device is attached to the lid member, A cooling structure for a semiconductor device, wherein the semiconductor device overlaps the opening when viewed in the first direction.

18. a cooler having a plurality of hollow portions each recessed in a first direction and arranged in a direction perpendicular to the first direction; a plurality of semiconductor devices attached to the cooler; When viewed in the first direction, the plurality of semiconductor devices are individually overlapped with the plurality of hollow portions, The cooler is provided with a plurality of inlet passages and a plurality of outlet passages that are set as a system different from the plurality of inlet passages, The plurality of inlet passages are individually connected to the plurality of internal spaces, The cooling structure for a semiconductor device, wherein the plurality of outlet paths are individually connected to the plurality of internal spaces.