Cooling structure for semiconductor device

Abstract

The cooling structure includes: a semiconductor device including a base material and a sealing resin; a cooler; and a bonding material that bonds the cooler and the base material. When viewed in the first direction, the bonding material overflows to the outside of the sealing resin. The bonding material has a first surface and a second surface facing opposite to each other in the first direction. The first surface is in contact with the base material. And the second surface is in contact with the cooler. And the area of the second surface is larger than that of the first surface.

Description

Technical Field

[0001] The present disclosure relates to a cooling structure for a semiconductor device. Background Art

[0002] An example of a semiconductor device including a cooler is disclosed in Patent Document 1. The cooler includes a radiator and a box having a hollow region. The box is provided with an opening leading to the hollow region. The radiator is attached to the box so as to block the opening. A part of the radiator is housed in the hollow region. The semiconductor device is bonded to a part of the radiator extending outward from the hollow region via a bonding material. When a refrigerant (such as cooling water) flows in the hollow region, the refrigerant contacts the radiator. Thus, the semiconductor device can be cooled via the radiator.

[0003] In the structure of the semiconductor device including the cooler disclosed in Patent Document 1, it is difficult to visually confirm the state of the bonding material that bonds the radiator to the semiconductor device through the appearance. If there is a defect in the bonding state, it may hinder heat conduction from the semiconductor device to the radiator. Therefore, it is preferable to be able to visually grasp the bonding state between the radiator and the semiconductor device.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: WO 2017 / 094370 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] One problem of the present disclosure is to provide a cooling structure for a semiconductor device that is improved compared to the prior art. In particular, in view of the above circumstances, one problem of the present disclosure is to provide a cooling structure for a semiconductor device that can improve the cooling efficiency of the semiconductor device and easily confirm the bonding state of the semiconductor device to the cooler.

[0009] Means for Solving the Problems

[0010] The cooling structure of a semiconductor device provided by one aspect of the present disclosure includes: a semiconductor device having a substrate; a conductive layer bonded to the substrate; a semiconductor element located on the side opposite to the substrate with respect to the conductive layer in a first direction and bonded to the conductive layer; and a sealing resin covering the conductive layer and the semiconductor element; a cooler; and a bonding material bonding the cooler and the substrate. When observed in the first direction, the bonding material overflows to the outside of the sealing resin. The bonding material has a first surface and a second surface facing opposite sides in the first direction. The first surface contacts the substrate. The second surface contacts the cooler. The area of the second surface is larger than the area of the first surface.

[0011] Advantages of the Invention

[0012] According to the above structure, the cooling efficiency of the semiconductor device can be improved, and the bonding state of the semiconductor device to the cooler can be easily confirmed.

[0013] Other features and advantages of the present disclosure will become more apparent from the following detailed description based on the drawings. Description of the Drawings

[0014] Figure 1 is a perspective view of a cooling structure of a semiconductor device according to a first embodiment of the present disclosure.

[0015] Figure 2 is Figure 1 a top view of the cooling structure of the semiconductor device shown.

[0016] Figure 3 is Figure 1 a right side view of the cooling structure of the semiconductor device shown.

[0017] Figure 4 is a cross-sectional view along line IV-IV of Figure 2 .

[0018] Figure 5 is a cross-sectional view along line V-V of Figure 2 .

[0019] Figure 6 is Figure 4 a partial enlarged view of

[0020] Figure 7 is Figure 5 a partial enlarged view of

[0021] Figure 8 is Figure 1 a top view of the semiconductor device included in the cooling structure of the semiconductor device shown.

[0022] Figure 9 is the top view corresponding to Figure 8 through the encapsulating resin.

[0023] Figure 10 is Figure 9 a partially enlarged view of

[0024] Figure 11 is the top view corresponding to Figure 8 through the first conduction component, and the illustration of the encapsulating resin and the second conduction component is omitted.

[0025] Figure 12 is Figure 8 the right side view of the semiconductor device shown in

[0026] Figure 13 is Figure 8 the bottom view of the semiconductor device shown in

[0027] Figure 14 is a cross-sectional view along line XIV-XIV of Figure 9

[0028] Figure 15 is a cross-sectional view along line XV-XV of Figure 9

[0029] Figure 16 is Figure 15 a partially enlarged view of the first element and its periphery shown in

[0030] Figure 17 is Figure 15 a partially enlarged view of the second element and its periphery shown in

[0031] Figure 18 is a cross-sectional view along line XVIII-XVIII of Figure 9

[0032] Figure 19 is a cross-sectional view along line XIX-XIX of Figure 9

[0033] Figure 20 is the top view of the cooling structure of the semiconductor device according to the second embodiment of the present disclosure.

[0034] Figure 21 is a cross-sectional view along line XXI-XXI of Figure 20

[0035] Figure 22 is a cross-sectional view along line XXII-XXII of Figure 20 Detailed implementation mode ​​​​​​

[0036] A description will be given of a method for implementing the present disclosure based on the accompanying drawings.

[0037] First Embodiment:

[0038] Based on Figures 1 to 19 , a cooling structure of a semiconductor device according to a first embodiment of the present disclosure (hereinafter referred to as "cooling structure A10") will be described. The cooling structure A10 includes a semiconductor device B, a bonding material 70, and a cooler 80.

[0039] In the description of the cooling structure A10, for convenience, the normal direction of the first main surface 121A of the first conductive layer 121 of the semiconductor device B to be described later is referred to as the "first direction z". The direction orthogonal to the first direction z is referred to as the "second direction x". The direction orthogonal to the first direction z and the second direction x is referred to as the "third direction y".

[0040] First, based on Figure 1 and Figures 8 to 19 , the semiconductor device B included in the cooling structure A10 will be described. The semiconductor device B may include a substrate 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 conduction member 31, a second conduction member 32, and a sealing resin 50. Further, the semiconductor device B 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. Here, in Figure 9 and Figure 10 , for easy understanding, through the sealing resin 50. In Figure 9 , the sealing resin 50 that is passed through is indicated by a phantom line (double-dot chain line). In Figure 11 , for easy understanding, through the first conduction member 31, and the illustration of the second conduction member 32 and the sealing resin 50 is omitted. In Figure 11 , the first conduction member 31 that is passed through is indicated by a phantom line. Further, in Figure 9 , the XV-XV line is indicated by a single-dot chain line.

[0041] The semiconductor device B is configured to convert a DC power supply voltage applied to the first input terminal 13 and the second input terminal 15 into AC power by a plurality of semiconductor elements 21. The converted AC power can be input from the output terminal 14 to a power supply object such as a motor.

[0042] As Figures 15 to 17As shown, the base material 11 can sandwich the first conductive layer 121 and the second conductive layer 122 in the first direction z and is located on the side opposite to the plurality of semiconductor elements 21. The base material 11 supports the first conductive layer 121 and the second conductive layer 122. In the semiconductor device B, the base material 11 is composed of a DBC (Direct Bonded Copper) substrate. As Figures 15 to 17 shown, the base material 11 includes an insulating layer 111, a pair of metal layers 112, and a heat dissipation layer 113. The base material 11 is covered with the encapsulation resin 50 except for a part of the heat dissipation layer 113.

[0043] As Figures 15 to 17 shown, the insulating layer 111 includes a portion interposed between the metal layer 112 and the heat dissipation layer 113 in the first direction z. The insulating layer 111 is a material with relatively high thermal conductivity. The insulating layer 111 is, for example, a ceramic including a sintered body of aluminum nitride (AlN). The insulating layer 111 can be composed of an insulating resin sheet or the like in addition to the ceramic. The thickness of the insulating layer 111 can be less than the thickness of each of the first conductive layer 121 and the second conductive layer 122.

[0044] As Figures 15 to 17 shown, the pair of metal layers 112 are located between the insulating layer 111 and the first conductive layer 121 and the second conductive layer 122 in the first direction z. The composition of the pair of metal layers 112 includes copper (Cu). As Figure 11 shown, when observed in the first direction z, the pair of metal layers 112 are respectively surrounded by the peripheral edge of the insulating layer 111.

[0045] As Figures 15 to 17 shown, the heat dissipation layer 113 sandwiches the insulating layer 111 in the first direction z and is located on the side opposite to the metal layer 112. As Figure 13 shown, the heat dissipation layer 113 is exposed from the encapsulation resin 50. The composition of the heat dissipation layer 113 includes copper. The thickness of the heat dissipation layer 113 is greater than the thickness of the insulating layer 111. When observed in the first direction z, the heat dissipation layer 113 is surrounded by the peripheral edge of the insulating layer 111.

[0046] As Figures 15 to 17 shown, the first conductive layer 121 and the second conductive layer 122 are joined to the base material 11. The composition of the first conductive layer 121 and the second conductive layer 122 includes copper. The first conductive layer 121 and the second conductive layer 122 are separated from each other in the second direction x. As Figure 14 and Figure 15 shown, the first conductive layer 121 has a first main surface 121A facing the first direction z. The first main surface 121A faces the plurality of semiconductor elements 21. As Figure 16As shown, it is joined to one of the pair of metal layers 112 via the first conductive layer 121 and the joining layer 123. The joining layer 123 is, for example, a solder containing silver (Ag) in its composition. As Figure 14 and Figure 15 shown, the second conductive layer 122 has a second main surface 122A facing the first direction z. The second main surface 122A can face the same side as the first main surface 121A in the first direction z. As Figure 17 shown, the second conductive layer 122 is joined to the other metal layer 112 of the pair of metal layers 112 via the joining layer 123. The dimensions of the first conductive layer 121 and the second conductive layer 122 in the first direction z are each larger than the dimension of the base material 11 in the first direction z.

[0047] As Figure 11 and Figure 15 shown, a plurality of semiconductor elements 21 are respectively mounted on either the first conductive layer 121 or the second conductive layer 122. The plurality of semiconductor elements 21 are, for example, MOSFETs (Metal - Oxide - Semiconductor Field - Effect Transistors). In addition, the plurality of semiconductor elements 21 can be switching elements such as IGBTs (Insulated Gate Bipolar Transistors), diodes, etc. In the description of the semiconductor device B, the semiconductor element 21 is an n - channel type and vertical - structure MOSFET. The plurality of semiconductor elements 21 can include a compound semiconductor substrate. The composition of this compound semiconductor substrate includes silicon carbide (SiC).

[0048] As Figure 11 shown, in the semiconductor device B, the plurality of semiconductor elements 21 include a plurality of first elements 21A and a plurality of second elements 21B. The structures of the plurality of second elements 21B are the same as the structures of the plurality of first elements 21A. The plurality of first elements 21A are mounted on the first main surface 121A of the first conductive layer 121. The plurality of first elements 21A are arranged along the third direction y. The plurality of second elements 21B are mounted on the second main surface 122A of the second conductive layer 122. The plurality of second elements 21B are arranged along the third direction y.

[0049] As Figure 11 , Figure 16 and Figure 17 shown, the plurality of semiconductor elements 21 each have a first electrode 211, a second electrode 212, a third electrode 213, and a fourth electrode 214.

[0050] As Figure 16 and Figure 17As shown, 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. That is, the first electrode 211 corresponds to the drain electrode of the semiconductor element 21.

[0051] As Figure 16 and Figure 17 shown, the second electrode 212 is located on the side opposite to the first electrode 211 in the first direction z. A current corresponding to the power after being converted by the semiconductor element 21 flows through the second electrode 212. That is, the second electrode 212 corresponds to the source electrode of the semiconductor element 21.

[0052] As Figure 16 and Figure 17 shown, 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 Figure 11 shown, when observed in the first direction z, the area of the third electrode 213 is smaller than the area of the second electrode 212.

[0053] As Figure 11 shown, the fourth electrode 214 is located on the same side as the second electrode 212 in the first direction z and is beside 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.

[0054] As Figure 16 and Figure 17 shown, 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 any one of the plurality of semiconductor elements 21. The conductive bonding layer 23 is, for example, solder. In addition, the conductive bonding layer 23 can be a structure including a sintered body of metal particles. The first electrodes 211 of the plurality of first elements 21A are conductively bonded to the first main surface 121A of the first conductive layer 121 via the conductive bonding layer 23. Thus, the first electrodes 211 of the plurality of first elements 21A can be electrically connected to the first conductive layer 121. The first electrodes 211 of the plurality of second elements 21B are conductively bonded to the second main surface 122A of the second conductive layer 122 via the conductive bonding layer 23. Thus, the first electrodes 211 of the plurality of second elements 21B are electrically connected to the second conductive layer 122.

[0055] As Figure 9 and Figure 15As shown, the first input terminal 13 is located on the side opposite to the second conductive layer 122 with the first conductive layer 121 sandwiched therebetween in the second direction x, and is connected to the first conductive layer 121. Thus, the first input terminal 13 is electrically connected to the first electrodes 211 of the plurality of 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 Figure 15 shown, the covering portion 13A is connected to the first conductive layer 121 and is covered with the encapsulating 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 covering portion 13A in the second direction x and is exposed from the encapsulating resin 50.

[0056] As Figure 9 and Figure 14 shown, the output terminal 14 is located on the side opposite to the first conductive layer 121 with the second conductive layer 122 sandwiched therebetween in the second direction x, and is connected to the second conductive layer 122. Thus, the output terminal 14 is electrically connected to the first electrodes 211 of the plurality of second elements 21B via the second conductive layer 122. The AC power converted by the plurality of semiconductor elements 21 is output from the output terminal 14. In the semiconductor device B, the output terminal 14 includes a pair of regions separated from each other in the third direction y. In addition, the output terminal 14 is a single structure that does not include the pair of regions. The output terminal 14 has a covering portion 14A and an exposed portion 14B. As Figure 14 shown, the covering portion 14A is connected to the second conductive layer 122 and is covered with the encapsulating 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 covering portion 14A in the second direction x and is exposed from the encapsulating resin 50.

[0057] As Figure 9 and Figure 14 shown, 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, and is located at a position away 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 separated 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 Figure 14As shown, the covering portion 15A is separated from the first conductive layer 121 and is covered with the encapsulating resin 50. The exposed portion 15B extends from the covering portion 15A in the second direction x and is exposed from the encapsulating resin 50.

[0058] A pair of control wirings 60 form a part of the conduction paths of the first signal terminal 161, the second signal terminal 162, the third signal terminal 171, the fourth signal terminal 172, a pair of fifth signal terminals 181, a pair of sixth signal terminals 182, and the plurality of semiconductor elements 21. As Figures 9 to 11 shown, 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, the first input terminal 13, and the second input terminal 15. The first wiring 601 is joined to the first main surface 121A of the first conductive layer 121. The first wiring 601 forms a part of the conduction path of 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 Figure 16 and Figure 17 shown, the pair of control wirings 60 has an insulating layer 61, a plurality of wiring layers 62, a metal layer 63, and a plurality of sleeves 64. The pair of control wirings 60 is covered with the encapsulating resin 50 except for a part of each of the plurality of sleeves 64.

[0059] As Figure 16 and Figure 17 shown, 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, for example, ceramic. The insulating layer 61 may have a structure such as an insulating resin sheet in addition to ceramic.

[0060] As Figure 16 and Figure 17 shown, the plurality of wiring layers 62 are located on one side of the insulating layer 61 in the first direction z. The composition of the plurality of wiring layers 62 may include copper. As Figure 11 shown, the plurality of 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.

[0061] As Figure 16 and Figure 17As shown, the metal layer 63 is located on the side opposite to the plurality of wiring layers 62 with the insulating layer 61 therebetween in the first direction z. The composition of the metal layer 63 may include copper. The metal layer 63 of the first wiring 601 is joined to the first main surface 121A of the first conductive layer 121 through the first adhesive layer 68. The metal layer 63 of the second wiring 602 is joined to the second main surface 122A of the second conductive layer 122 through the first adhesive layer 68. The first adhesive layer 68 is a material regardless of conductivity. The first adhesive layer 68 is, for example, solder.

[0062] As Figure 16 and Figure 17 shown, the plurality of sleeves 64 are respectively joined to any one of the plurality of wiring layers 62 through the second adhesive layer 69. The plurality of sleeves 64 are conductive materials such as metal. Each of the plurality of sleeves 64 is in a cylindrical shape extending along the first direction z. One end of each of the plurality of sleeves 64 is conductively joined to any one of the plurality of wiring layers 62. As Figure 8 and Figure 15 shown, the end surfaces 641 corresponding to the other ends of the plurality of sleeves 64 are exposed from the top surface 51 of the encapsulating resin 50 described later. The second adhesive layer 69 has conductivity. The second adhesive layer 69 is, for example, solder.

[0063] As Figure 10 shown, one of the pair of thermistors 22 is conductively joined to a pair of third wiring layers 623 of the first wiring 601. Figure 10 As shown, the other thermistor 22 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. The NTC thermistor has the characteristic that the resistance decreases slowly with the increase in temperature. The pair of thermistors 22 are used as sensors for detecting the temperature of the semiconductor device B.

[0064] As Figure 1 shown, 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 respectively metal pins extending along the first direction z. These terminals can protrude from the top surface 51 of the encapsulating resin 50 described later. In addition, these terminals are respectively pressed into the plurality of sleeves 64 of the pair of control wirings 60. Thus, each of these terminals is supported by any one of the plurality of sleeves 64 and is electrically connected to any one of the plurality of wiring layers 62.

[0065] As Figure 11 and Figure 16As shown, the first signal terminal 161 is pressed into a sleeve 64 of a plurality of sleeves 64 of a pair of control wirings 60 that is joined to a first wiring layer 621 of a first wiring 601. Thus, the first signal terminal 161 is supported by the sleeve 64 and is electrically connected to the first wiring layer 621 of the first wiring 601. Further, the first signal terminal 161 is electrically connected to third electrodes 213 of a plurality of first elements 21A. A gate voltage for driving the plurality of first elements 21A can be applied to the first signal terminal 161.

[0066] As Figure 11 and Figure 17 shown, the second signal terminal 162 is pressed into a sleeve 64 of a plurality of sleeves 64 of a pair of control wirings 60 that is joined to a first wiring layer 621 of a second wiring 602. Thus, the second signal terminal 162 is supported by the sleeve 64 and is electrically connected to the first wiring layer 621 of the second wiring 602. Further, the second signal terminal 162 is electrically connected to third electrodes 213 of a plurality of second elements 21B. A gate voltage for driving the plurality of second elements 21B is applied to the second signal terminal 162.

[0067] As Figure 8 shown, the third signal terminal 171 is located beside the first signal terminal 161 in the third direction y. As Figure 11 shown, the third signal terminal 171 is pressed into a sleeve 64 of a plurality of sleeves 64 of a pair of control wirings 60 that is joined to a second wiring layer 622 of the first wiring 601. Thus, the third signal terminal 171 is supported by the sleeve 64 and is electrically connected to the second wiring layer 622 of the first wiring 601. Further, the third signal terminal 171 is electrically connected to fourth electrodes 214 of a plurality of first elements 21A. A voltage corresponding to the maximum current among the currents flowing through the fourth electrodes 214 of the respective first elements 21A is applied to the third signal terminal 171.

[0068] As Figure 8 shown, the fourth signal terminal 172 is located beside the second signal terminal 162 in the third direction y. As Figure 11 shown, the fourth signal terminal 172 is pressed into a sleeve 64 of a plurality of sleeves 64 of a pair of control wirings 60 that is joined to a second wiring layer 622 of the second wiring 602. Thus, the fourth signal terminal 172 is supported by the sleeve 64 and is electrically connected to the second wiring layer 622 of the second wiring 602. Further, the fourth signal terminal 172 is electrically connected to fourth electrodes 214 of a plurality of second elements 21B. A voltage corresponding to the maximum current among the currents flowing through the fourth electrodes 214 of the respective second elements 21B can be applied to the fourth signal terminal 172.

[0069] As Figure 8As shown, a pair of fifth signal terminals 181 are located on the opposite side of the third signal terminal 171 across the first signal terminal 161 in the third direction y. The pair of fifth signal terminals 181 are adjacent to each other in the third direction y. As Figure 11 shown, the pair of fifth signal terminals 181 are respectively pressed into a pair of sleeves 64 of the plurality of sleeves 64 of the pair of control wirings 60 that are joined to a pair of third wiring layers 623 of the first wiring 601. Thus, 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 wiring 601. In addition, the pair of fifth signal terminals 181 are electrically connected to a pair of thermistors 22 that are conductively joined to the pair of third wiring layers 623 of the first wiring 601.

[0070] As Figure 8 shown, a pair of sixth signal terminals 182 are located on the opposite side of the fourth signal terminal 172 across the second signal terminal 162 in the third direction y. The pair of sixth signal terminals 182 are adjacent to each other in the third direction y. As Figure 11 shown, the pair of sixth signal terminals 182 are respectively pressed into a pair of sleeves 64 of the plurality of sleeves 64 of the pair of control wirings 60 that are joined to a pair of third wiring layers 623 of the second wiring 602. Thus, 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 wiring 602. In addition, the pair of sixth signal terminals 182 are electrically connected to a pair of thermistors 22 that are conductively joined to the pair of third wiring layers 623 of the second wiring 602.

[0071] As Figure 8 shown, the seventh signal terminal 19 is located on the opposite side of the first signal terminal 161 across the third signal terminal 171 in the third direction y. As Figure 11 shown, the seventh signal terminal 19 is pressed into a sleeve 64 of the plurality of sleeves 64 of the pair of control wirings 60 that is joined to the fifth wiring layer 625 of the first wiring 601. Thus, the seventh signal terminal 19 is supported by the sleeve 64 and is electrically connected to the fifth wiring layer 625 of the first wiring 601. In addition, 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 can be applied to the seventh signal terminal 19.

[0072] As Figure 11 shown, a plurality of first wires 41 are conductively joined to the third electrodes 213 of the plurality of first elements 21A and the fourth wiring layer 624 of the first wiring 601. As Figure 11As shown, multiple third wires 43 are conductively joined to the fourth wiring layer 624 of the first wiring 601 and the first wiring layer 621 of the first wiring 601. Thus, the first signal terminal 161 is 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). In addition, the composition of the multiple first wires 41 and the multiple third wires 43 can be a case including copper or a case including aluminum (Al).

[0073] And, as Figure 11 shown, multiple first wires 41 are conductively joined to the third electrodes 213 of the multiple second elements 21B and the fourth wiring layer 624 of the second wiring 602. And, as Figure 11 shown, multiple 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. Thus, the second signal terminal 162 is electrically connected to the third electrodes 213 of the multiple second elements 21B.

[0074] As Figure 11 shown, multiple second wires 42 are conductively joined to the fourth electrodes 214 of the multiple first elements 21A and the second wiring layer 622 of the first wiring 601. Thus, the third signal terminal 171 is electrically connected to the fourth electrodes 214 of the multiple first elements 21A. And, as Figure 11 shown, multiple second wires 42 are conductively joined to the fourth electrodes 214 of the multiple second elements 21B and the second wiring layer 622 of the second wiring 602. Thus, 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 can include gold. In addition, the composition of the multiple second wires 42 can be a case including copper or a case including aluminum.

[0075] As Figure 11 shown, the fourth wire 44 is conductively joined to the fifth wiring layer 625 of the first wiring 601 and the first main surface 121A of the first conductive layer 121. Thus, the seventh signal terminal 19 is electrically connected to the first conductive layer 121. The composition of the fourth wire 44 includes gold. In addition, the composition of the fourth wire 44 is a case including copper or a case including aluminum.

[0076] As Figure 11 and Figure 16 shown, the first conduction member 31 is conductively joined to the second electrodes 212 of the multiple first elements 21A and the second main surface 122A of the second conductive layer 122. Thus, the second electrodes 212 of the multiple first elements 21A are electrically connected to the second conductive layer 122. The composition of the first conduction member 31 can include copper. The first conduction member 31 can be a metal clip. As Figure 11As shown, the first conduction member 31 has a main body portion 311, a plurality of first joint portions 312, a plurality of first connection portions 313, a second joint portion 314, and a second connection portion 315.

[0077] The main body portion 311 constitutes the main part of the first conduction member 31. As Figure 11 shown, the main body portion 311 extends along the third direction y. As Figure 15 shown, the main body portion 311 straddles between the first conductive layer 121 and the second conductive layer 122.

[0078] As Figure 16 shown, the plurality of first joint portions 312 are respectively joined to the second electrodes 212 of the plurality of first elements 21A. The plurality of first joint portions 312 are respectively opposed to any one of the second electrodes 212 of the plurality of first elements 21A.

[0079] As Figure 11 shown, the plurality of first connection portions 313 are connected to the main body portion 311 and the plurality of first joint portions 312. The plurality of first connection portions 313 are separated from each other in the third direction y. As Figure 15 shown, when observed along the third direction y, the plurality of first connection portions 313 are inclined in a direction away from the first main surface 121A of the first conductive layer 121 as they approach the main body portion 311 from the plurality of first joint portions 312.

[0080] As Figure 11 and Figure 15 shown, the second joint portion 314 is joined to the second main surface 122A of the second conductive layer 122. The second joint portion 314 is opposed to the second main surface 122A. The second joint portion 314 extends in the third direction y. The dimension of the second joint portion 314 in the third direction y is equal to the dimension of the main body portion 311 in the third direction y.

[0081] As Figure 11 and Figure 15 shown, the second connection portion 315 is connected to the main body portion 311 and the second joint portion 314. When observed along the third direction y, the second connection portion 315 is inclined in a direction away from the second main surface 122A of the second conductive layer 122 as it approaches the main body portion 311 from the second joint portion 314. The dimension of the second connection portion 315 in the third direction y is equal to the dimension of the main body portion 311 in the third direction y.

[0082] As Figure 15 、 Figure 16 and Figure 19As shown, 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 electrically conducts and bonds 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 is, for example, solder. In addition, the first conductive bonding layer 33 may be a sintered body including metal particles.

[0083] As Figure 15 shown, 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 electrically conducts and bonds the second main surface 122A and the second bonding portion 314. The second conductive bonding layer 34 is, for example, solder. In addition, the second conductive bonding layer 34 may be a sintered body including metal particles.

[0084] As Figure 10 and Figure 17 shown, the second conduction member 32 is electrically conductively bonded to the second electrodes 212 of the plurality of second elements 21B and the covering portion 15A of the second input terminal 15. As a result, the second electrodes 212 of the plurality of second elements 21B and the second input terminal 15 are electrically connected. The second conduction member 32 is composed of copper. The second conduction member 32 may be a metal clip. As Figure 10 shown, the second conduction member 32 has a pair of main body portions 321, a plurality of third bonding portions 322, a plurality of third connecting portions 323, a pair of fourth bonding portions 324, a pair of fourth connecting portions 325, a plurality of intermediate portions 326, and a plurality of cross beam portions 327.

[0085] As Figure 10 shown, the pair of main body portions 321 are separated from each other in the third direction y. The pair of main body portions 321 extend in the second direction x. As Figure 14 shown, the pair of main body portions 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 body portions 321 are farther from the first main surface 121A and the second main surface 122A than the main body portion 311 of the first conduction member 31.

[0086] As Figure 10 shown, the plurality of intermediate portions 326 are separated from each other in the third direction y and are located between the pair of main body portions 321 in the third direction y. The plurality of intermediate portions 326 extend in the second direction x. The size of each of the plurality of intermediate portions 326 in the second direction x is smaller than the size of each of the pair of main body portions 321 in the second direction x.

[0087] As Figure 17As shown, a plurality of third bonding portions 322 are individually bonded to second electrodes 212 of a plurality of second elements 21B. The plurality of third bonding portions 322 face any one of the second electrodes 212 of the plurality of second elements 21B respectively.

[0088] As Figure 10 and Figure 18 shown, a plurality of third connecting portions 323 are connected to both sides of the plurality of third bonding portions 322 in the third direction y. Further, the plurality of third connecting portions 323 are connected to any one of a pair of main body portions 321 and a plurality of intermediate portions 326. When viewed along the second direction x, the plurality of third connecting portions 323 are inclined in a direction away from the second main surface 122A of the second conductive layer 122 as they approach any one of the pair of main body portions 321 and the plurality of intermediate portions 326 from any one of the plurality of third bonding portions 322.

[0089] As Figure 10 and Figure 14 shown, a pair of fourth bonding portions 324 are bonded to a covering portion 15A of the second input terminal 15. The pair of fourth bonding portions 324 face the covering portion 15A.

[0090] As Figure 10 and Figure 14 shown, a pair of fourth connecting portions 325 are connected to the pair of main body portions 321 and the pair of fourth bonding portions 324. When viewed along 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 approach the pair of main body portions 321 from the pair of fourth bonding portions 324.

[0091] As Figure 10 and Figure 19 shown, a plurality of cross beam portions 327 are arranged along the third direction y. When viewed along the first direction z, the plurality of cross beam portions 327 include regions that respectively overlap with a plurality of first bonding portions 312 of the first conduction member 31. Both sides of the cross beam portion 327 located at the center in the third direction y among the plurality of cross beam portions 327 are connected to the plurality of intermediate portions 326. Both sides of the remaining two cross beam portions 327 among the plurality of cross beam portions 327 are connected to any one of the pair of main body portions 321 and any one of the plurality of intermediate portions 326. When viewed along the second direction x, the plurality of cross beam portions 327 are convex in the first direction z toward the side where the first main surface 121A of the first conductive layer 121 faces.

[0092] As Figure 15 、 Figure 17 and Figure 18As shown, 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 electrically bonds 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 is, for example, solder. In addition, the third conductive bonding layer 35 may be a sintered body including metal particles.

[0093] As Figure 14 shown, 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 bonding portions 324. The fourth conductive bonding layer 36 electrically bonds the covering portion 15A and the pair of fourth bonding portions 324. The fourth conductive bonding layer 36 is, for example, solder. In addition, the fourth conductive bonding layer 36 may be a sintered body including metal particles.

[0094] As Figure 14 , Figure 15 , Figure 18 and Figure 19 shown, the encapsulating resin 50 covers the first conductive layer 121, the second conductive layer 122, the plurality of semiconductor elements 21, the first conduction member 31, and the second conduction member 32. And, the encapsulating resin 50 covers a part of each of the base material 11, the first input terminal 13, the output terminal 14, and the second input terminal 15. The encapsulating resin 50 has electrical insulation. The encapsulating resin 50 may be, for example, a material including a black epoxy resin. As Figure 8 and Figures 12 to 15 shown, the encapsulating 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.

[0095] As Figure 14 and Figure 15 shown, the top surface 51 faces the same side as the first main surface 121A of the first conductive layer 121 in the first direction z. As Figure 14 and Figure 15 shown, the bottom surface 52 faces the side opposite to the top surface 51 in the first direction z. As Figure 13 shown, the heat dissipation layer 113 of the base material 11 is exposed from the bottom surface 52.

[0096] As Figure 8 and Figure 12As shown, a pair of first side surfaces 53 are separated from each other in the second direction x. The pair of first side surfaces 53 face the second direction x and extend along the third direction y. The pair of first side surfaces 53 are connected to the top surface 51. The exposed portions 13B of the first input terminals 13 and the exposed portions 15B of the second input terminals 15 are exposed from one of the pair of first side surfaces 53. The exposed portion 14B of the output terminal 14 is exposed from the other of the pair of first side surfaces 53.

[0097] As Figure 8 and Figure 13 shown, a pair of second side surfaces 54 are separated from each other in the third direction y. The pair of second side surfaces 54 face opposite sides 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.

[0098] As Figure 8 and Figure 13 shown, a pair of recesses 55 are recessed from the first side surface 53 of the pair of first side surfaces 53 that exposes the exposed portions 13B of the first input terminals 13 and the exposed portions 15B of the second input terminals 15, in the second direction x. The pair of recesses 55 reach 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.

[0099] Next, based on Figures 1 to 7 , the bonding material 70 and the cooler 80 included in the cooling structure A10 will be described.

[0100] The cooler 80 is used for cooling the semiconductor device B. The cooler 80 can be, for example, a material including aluminum.

[0101] As Figures 2 to 5 shown, the cooler 80 has a housing 81 and a heat sink 82. The housing 81 has a hollow portion 811, an inlet 812, and an outlet 813. The hollow portion 811 is located inside the housing 81. The inlet 812 and the outlet 813 are connected to the hollow portion 811. The inlet 812 and the outlet 813 are located on opposite sides with respect to the hollow portion 811 in the third direction y. In the cooler 80, a structure can be formed in which the refrigerant flows from the inlet 812 through the hollow portion 811 to the outlet 813.

[0102] As Figures 2 to 5 shown, the housing 81 has a mounting surface 81A facing the first direction z. The mounting surface 81A faces the heat dissipation layer 113 of the base material 11.

[0103] As Figures 2 to 5As shown, the hollow portion 811 of the box body 81 includes a sudden contraction portion 811A. The sudden contraction portion 811A refers to the portion where the cross-sectional area of the hollow portion 811 is the smallest in the direction orthogonal to the first direction z and in the interval from the inflow port 812 to the outflow port 813.

[0104] As Figures 2 to 5 shown, the heat sink 82 is received in the sudden contraction portion 811A of the hollow portion 811 of the box body 81. The heat sink 82 is connected to the box body 81. As Figure 2 and Figure 5 shown, the heat sink 82 may be a plurality of fins separated from each other in the second direction x. As Figure 2 and Figure 4 shown, each of the plurality of fins extends in the third direction y. Therefore, the plurality of fins respectively extend in the direction orthogonal to the first direction z and along the interval from the inflow port 812 to the outflow port 813.

[0105] As Figure 2 shown, when observed in the first direction z, the first conductive layer 121 and the second conductive layer 122 respectively overlap with the sudden contraction portion 811A of the hollow portion 811 of the box body 81. In addition, when observed along the first direction z, each of the first conductive layer 121 and the second conductive layer 122 overlaps with the heat sink 82.

[0106] As Figure 4 and Figure 5 shown, the bonding material 70 bonds the box body 81 of the cooler 80 to the heat dissipation layer 113 of the base material 11. As Figure 2 shown, when observed along the first direction z, the bonding material 70 overflows to the outside of the encapsulating resin 50.

[0107] As Figure 6 and Figure 7 shown, the bonding material 70 has a first surface 71 and a second surface 72 facing opposite sides in the first direction z. The first surface 71 contacts the heat dissipation layer 113 of the base material 11. The second surface 72 contacts the mounting surface 81A of the box body 81 of the cooler 80. The area of the second surface 72 is larger than the area of the first surface 71. As Figure 2 shown, the whole of the first surface 71 overlaps with the second surface 72. As Figure 4 and Figure 6 shown, the first surface 71 contacts the bottom surface 52 of the encapsulating resin 50.

[0108] As Figure 2 shown, the peripheral edge 721 of the second surface 72 includes an interval that is a convex curve.

[0109] As Figure 6As shown, the bonding material 70 has an end face 73 facing a direction orthogonal to the first direction z. The end face 73 bulges outward from the bonding material 70.

[0110] As Figure 6 shown, the dimension of the bonding material 70 in the first direction z is smaller than the dimension of the heat dissipation layer 113 of the base material 11 in the first direction z. The dimension of the bonding material 70 in the first direction z can be set to 1 / 10 or less of the dimension of the heat dissipation layer 113 in the first direction z.

[0111] As Figure 2 shown, when observed in the first direction z, the exposed portions 13B of the first input terminal 13, the exposed portions 14B of the output terminal 14, and the exposed portions 15B of the second input terminal 15 are separated from the cooler 80 and the bonding material 70, respectively.

[0112] As Figure 1 and Figure 2 shown, in the cooling structure A10, the entire top surface 51 of the encapsulating resin 50 is exposed to the outside.

[0113] Furthermore, regarding the cooling structure A10, through the analysis conducted by the inventors of the present disclosure, the following insights are obtained. When the Young's modulus of the insulating layer 111 of the base material 11 is 300 GPa or more and the difference in the linear expansion coefficient between the cooler 80 and the insulating layer 111 is 12×10 -6 (1 / K) or more, it is preferable to set the dimension of the bonding material 70 in the first direction z to 40 μm or more. Furthermore, when the Young's modulus of the insulating layer 111 is 30 GPa or less and the difference in the linear expansion coefficient between the cooler 80 and the insulating layer 111 is 50×10 -6 (1 / K) or less, it is preferable to set the dimension of the bonding material 70 in the first direction z to 20 μm or more. Thus, when thermal stress caused by heat generated from the semiconductor device B acts on the bonding material 70, the maximum thermal stress is smaller than the yield stress of the bonding material 70.

[0114] Next, the effects of the cooling structure A10 will be described.

[0115] The cooling structure A10 includes: a semiconductor device B having a substrate 11 and a sealing resin 50; a cooler 80; and a bonding material 70 that bonds the cooler 80 to the substrate 11. When observed in the first direction z, the bonding material 70 overflows to the outside of the sealing resin 50. The bonding material 70 has a first surface 71 in contact with the substrate 11 and a second surface 72 in contact with the cooler 80. By adopting this structure in which the area of the second surface 72 is larger than the area of the first surface 71, the state of the bonding material 70 can be visually confirmed. Moreover, since the area of the second surface 72 is larger than the area of the first surface 71, heat in the bonding material 70 easily diffuses in a direction orthogonal to the first direction z. Thereby, the thermal resistance of the bonding material 70 in the first direction z can be reduced. Therefore, according to this structure, in the cooling structure A10, the cooling efficiency of the semiconductor device B can be improved, and the bonding state of the semiconductor device B to the cooler 80 can be easily confirmed.

[0116] When observed in the first direction z, the entire first surface 71 of the bonding material 70 overlaps with the second surface 72 of the bonding material 70. By adopting this structure, in the bonding material 70, heat can be more uniformly diffused in a direction orthogonal to the first direction z. Thereby, the deviation of the distribution of the thermal resistance (thermal resistance in the first direction z) of the bonding material 70 in a direction orthogonal to the first direction z can be suppressed.

[0117] The first surface 71 of the bonding material 70 is in contact with the bottom surface 52 of the sealing resin 50. By adopting this structure, the contact area of the bonding material 70 with respect to the semiconductor device B can be increased. Thereby, the bonding strength between the cooler 80 and the semiconductor device B can be improved.

[0118] When observed in the first direction z, the peripheral edge 721 of the second surface 72 of the bonding material 70 includes an interval that is a convex curve. Furthermore, the end surface 73 of the bonding material 70 bulges outward from the bonding material 70. This structure means that the viscosity of the bonding material 70 is relatively large and a sufficient compressive stress in the first direction z is applied to the bonding material 70 when the semiconductor device B is bonded to the cooler 80. Thereby, this structure becomes an index of a better bonding state between the cooler 80 and the semiconductor device B.

[0119] In the cooling structure A10, the entire top surface 51 of the sealing resin 50 is exposed to the outside. This structure means that no mounting member for fixing the semiconductor device B to the cooler 80 is required. Thereby, especially when the mounting member is made of metal, a reduction in the insulation breakdown voltage of the semiconductor device B can be suppressed.

[0120] The semiconductor device B further includes a first input terminal 13 electrically connected to the first conductive layer 121 and a second input terminal 15 electrically connected to the second conductive layer 122. When observed in the first direction z, the exposed portions 13B of the first input terminal 13 and 15B of the second input terminal 15 are separated from the cooler 80 and the bonding material 70, respectively. By adopting this structure, a decrease in the breakdown voltage of the semiconductor device B can be suppressed.

[0121] The dimensions of the first conductive layer 121 and the second conductive layer 122 in the first direction z are larger than the dimensions of the base material 11 in the first direction z. By adopting this structure, in each of the first conductive layer 121 and the second conductive layer 122, heat easily diffuses in a direction orthogonal to the first direction z. Thereby, the thermal resistance of each of the first conductive layer 121 and the second conductive layer 122 in the first direction z can be reduced.

[0122] In the cooling structure A10, the cooler 80 has a housing 81 that contacts the second surface 72 of the bonding material 70. The housing 81 has a hollow portion 811 located inside the housing 81, and an inlet 812 and an outlet 813 that communicate with the hollow portion 811. When observed in the first direction z, the first conductive layer 121 overlaps with the hollow portion 811. By adopting this structure, the refrigerant can flow through the hollow portion 811, so that the cooling efficiency of the semiconductor device B can be improved.

[0123] The hollow portion 811 of the housing 81 includes a constriction portion 811A having the smallest cross-sectional area in the interval from the inlet 812 to the outlet 813 in a direction orthogonal to the first direction z. When observed along the first direction z, the first conductive layer 121 overlaps with the constriction portion 811A. By adopting this structure, the flow velocity of the refrigerant in the constriction portion 811A can be increased, so that the cooling efficiency of the semiconductor device B can be further improved.

[0124] The cooler 80 has a heat sink 82 housed in the constriction portion 811A of the housing 81 and connected to the housing 81. When observed in the first direction z, the first conductive layer 121 and the second conductive layer 122 respectively overlap with the heat sink 82. By adopting this structure, the contact area of the cooler 80 with respect to the refrigerant is enlarged, so that the cooling efficiency of the semiconductor device B can be further improved.

[0125] The heat sink 82 includes a plurality of fins. The plurality of fins respectively extend in a direction orthogonal to the first direction z and along the direction of the interval from the inlet 812 to the outlet 813. By adopting this structure, the obstruction of the flow of the refrigerant in the constriction portion 811A of the cooler 80 can be suppressed.

[0126] Second Embodiment:

[0127] Based on Figures 20 to 22, a cooling structure of the semiconductor device according to the second embodiment of the present disclosure (hereinafter referred to as "cooling structure A20") will be described. In these figures, the same or similar elements as those of the above cooling structure A10 are denoted by the same reference numerals, and redundant descriptions are omitted.

[0128] In the cooling structure A20, the structure of the cooler 80 is different from that of the cooling structure A10.

[0129] As Figures 20 to 22 shown, the cooler 80 has a base 83 and a heat dissipation portion 84 instead of the box 81 and the heat dissipation body 82. The base 83 is in a flat plate shape. The base 83 has a mounting surface 83A and a back surface 83B. The mounting surface 83A and the back surface 83B can face opposite sides in the first direction z. The mounting surface 83A faces the heat dissipation layer 113 of the substrate 11. The second surface 72 of the bonding material 70 is in contact with the mounting surface 83A.

[0130] As Figure 21 and Figure 22 shown, the heat dissipation portion 84 protrudes from the back surface 83B of the base 83 in the first direction z. The heat dissipation portion 84 is located on the side opposite to the substrate 11 with respect to the base 83 in the first direction z. The heat dissipation portion 84 is exposed to the outside. The heat dissipation portion 84 may be a plurality of pins separated from each other in a direction orthogonal to the first direction z. As viewed from the first direction z, as Figure 20 shown, the heat dissipation portion 84 overlaps with the first conductive layer 121 and the second conductive layer 122, respectively.

[0131] Next, the effects of the cooling structure A20 will be described.

[0132] The cooling structure A20 includes: a semiconductor device B having a substrate 11 and a sealing resin 50; a cooler 80; and a bonding material 70 that bonds the cooler 80 to the substrate 11. When viewed along the first direction z, the bonding material 70 can overflow to the outside of the sealing resin 50. The bonding material 70 has a first surface 71 in contact with the substrate 11 and a second surface 72 in contact with the cooler 80. The area of the second surface 72 is larger than the area of the first surface 71. Therefore, according to this structure, in the cooling structure A20, it is also possible to improve the cooling efficiency of the semiconductor device B and easily confirm the bonding state of the semiconductor device B with respect to the cooler 80. Furthermore, since the cooling structure A20 has a structure common to the cooling structure A10, it exhibits the same effects as the cooling structure A10.

[0133] In the cooling structure A20, there are a base 83 in contact with the second surface 72 of the bonding material 70 and a heat dissipation portion 84 protruding from the base 83 in the first direction z. The heat dissipation portion 84 is exposed to the outside. When observed in the first direction z, the first conductive layer 121 and the second conductive layer 122 respectively overlap with the heat dissipation portion 84. By adopting this structure, the surface area of the cooler 80 is further enlarged, so that the cooling efficiency of the semiconductor device B can be improved.

[0134] The present disclosure is not limited to the above-described embodiments. Various design changes can be freely made to the specific structures of the respective parts of the present disclosure.

[0135] The present disclosure includes the embodiments described in the following appended notes.

[0136] Appended Note 1. A cooling structure of a semiconductor device, comprising:

[0137] A semiconductor device, comprising: a substrate; a conductive layer bonded to the substrate; a semiconductor element located on the side opposite to the substrate with respect to the conductive layer in a first direction and bonded to the conductive layer; and a sealing resin covering the conductive layer and the semiconductor element;

[0138] A cooler; and

[0139] A bonding material that bonds the cooler and the substrate,

[0140] When observed in the first direction, the bonding material overflows to the outside of the sealing resin,

[0141] The bonding material has a first surface and a second surface facing opposite sides in the first direction,

[0142] The first surface is in contact with the substrate,

[0143] The second surface is in contact with the cooler,

[0144] The area of the second surface is larger than the area of the first surface.

[0145] Appended Note 2. The cooling structure of the semiconductor device according to Appended Note 1, wherein

[0146] When observed in the first direction, the whole of the first surface overlaps with the second surface.

[0147] Appended Note 3. The cooling structure of the semiconductor device according to Appended Note 2, wherein

[0148] The sealing resin has a bottom surface facing the side opposite to the cooler in the first direction,

[0149] The first surface is in contact with the bottom surface.

[0150] Supplementary Note 4. The cooling structure of the semiconductor device according to Supplementary Note 3, wherein,

[0151] The encapsulating resin has a top surface facing the side opposite to the bottom surface in the first direction,

[0152] The entire top surface is exposed to the outside.

[0153] Supplementary Note 5. The cooling structure of the semiconductor device according to Supplementary Note 4, wherein,

[0154] When observed in the first direction, the periphery of the second surface includes an interval that is a convex curve.

[0155] Supplementary Note 6. The cooling structure of the semiconductor device according to Supplementary Note 5, wherein,

[0156] The bonding material has an end face facing a direction orthogonal to the first direction,

[0157] The end face bulges outwards from the bonding material.

[0158] Supplementary Note 7. The cooling structure of the semiconductor device according to Supplementary Note 6, wherein,

[0159] The semiconductor element is electrically bonded to the conductive layer.

[0160] Supplementary Note 8. The cooling structure of the semiconductor device according to Supplementary Note 7, wherein,

[0161] The dimension of the conductive layer in the first direction is larger than the dimension of the substrate in the first direction.

[0162] Supplementary Note 9. The cooling structure of the semiconductor device according to Supplementary Note 8, wherein,

[0163] The semiconductor device includes a first input terminal and a second input terminal that are electrically connected to the conductive layer,

[0164] The first input terminal and the second input terminal each have an exposed portion that protrudes from the encapsulating resin,

[0165] When observed in the first direction, the exposed portion is separated from the cooler and the bonding material.

[0166] Supplementary Note 10. The cooling structure of the semiconductor device according to any one of Supplementary Notes 1 to 9, wherein,

[0167] The base material has an insulating layer, a metal layer laminated on the insulating layer, and a heat dissipation layer located on the side opposite to the insulating layer and laminated on the insulating layer.

[0168] The conductive layer is joined to the metal layer.

[0169] The first surface is in contact with the heat dissipation layer.

[0170] Supplementary Note 11. The cooling structure of the semiconductor device according to Supplementary Note 10, wherein

[0171] The dimension of the joining material in the first direction is smaller than the dimension of the heat dissipation layer in the first direction.

[0172] Supplementary Note 12. The cooling structure of the semiconductor device according to Supplementary Note 10, wherein

[0173] The cooler has a housing that the second surface contacts.

[0174] The housing has a hollow portion inside the housing, and an inlet and an outlet that communicate with the hollow portion.

[0175] When observed in the first direction, the conductive layer overlaps with the hollow portion.

[0176] Supplementary Note 13. The cooling structure of the semiconductor device according to Supplementary Note 12, wherein

[0177] The hollow portion includes a sudden contraction portion, and the cross-sectional area of the sudden contraction portion is the smallest in the direction orthogonal to the first direction and in the section from the inlet to the outlet.

[0178] When observed in the first direction, the conductive layer overlaps with the sudden contraction portion.

[0179] Supplementary Note 14. The cooling structure of the semiconductor device according to Supplementary Note 13, wherein

[0180] The cooler has a heat dissipation body that is received in the sudden contraction portion and is connected to the housing.

[0181] When observed in the first direction, the conductive layer overlaps with the heat dissipation body.

[0182] Supplementary Note 15. The cooling structure of the semiconductor device according to Supplementary Note 14, wherein

[0183] The heat dissipation body includes a plurality of fins.

[0184] The plurality of fins respectively extend in the direction orthogonal to the first direction and along the direction of the section from the inlet to the outlet.

[0185] Supplementary Note 16. The cooling structure of the semiconductor device according to Supplementary Note 10, wherein,

[0186] The cooler has: a base portion that contacts the second surface; and a heat dissipation portion that is located on the side opposite to the base material with respect to the base portion and protrudes from the base portion in the first direction,

[0187] The heat dissipation portion is exposed to the outside,

[0188] When viewed in the first direction, the conductive layer overlaps with the heat dissipation portion.

[0189] Symbol Explanation

[0190] A10, A20 - Cooling structure, B - Semiconductor device, 11 - Substrate, 111 - Insulating layer, 112 - Intermediate layer, 113 - Heat dissipation layer, 121 - First conductive layer, 121A - First main surface, 122 - Second conductive layer, 122A - Second main surface, 123 - Bonding 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 conduction member, 311 - Main body portion, 312 - First bonding portion, 313 - First connection portion, 314 - Second bonding portion, 315 - Second connection portion, 32 - Second conduction member, 321 - Main body portion, 322 - Third bonding portion, 323 - Third connection portion, 324 - Fourth bonding portion, 325 - Fourth connection portion, 326 - Intermediate portion, 327 - Crossbeam 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 face, 68 - First adhesive layer, 69 - Second adhesive layer, 70 - Bonding material, 71 - First surface, 72 - Second surface, 721 - Periphery, 73 - End face, 80 - Cooler, 81 - Box body, 81A - Mounting surface, 811 - Hollow portion, 811A - Sharp constriction portion, 812 - Inlet, 813 - Outlet, 82 - Heat sink, 83 - Base, 83A - Mounting surface, 83B - Back surface, 84 - Heat dissipation portion, z - First direction, x - Second direction, y - Third direction.

Claims

1. A cooling structure of a semiconductor device, characterized in that, it includes: a semiconductor device, which includes: a substrate; a conductive layer joined to the substrate; a semiconductor element located on the side opposite to the substrate with respect to the conductive layer in a first direction and joined to the conductive layer; and a sealing resin covering the conductive layer and the semiconductor element; a cooler; and a bonding material joining the cooler and the substrate, when observed in the first direction, the bonding material overflows to the outside of the sealing resin, the bonding material has a first surface and a second surface facing opposite sides in the first direction, the first surface contacts the substrate, the second surface contacts the cooler, the area of the second surface is larger than the area of the first surface.

2. The cooling structure of a semiconductor device according to claim 1, characterized in that, when observed in the first direction, the whole of the first surface overlaps with the second surface.

3. The cooling structure of a semiconductor device according to claim 2, characterized in that, the sealing resin has a bottom surface facing the side opposite to the cooler in the first direction, the first surface contacts the bottom surface.

4. The cooling structure of a semiconductor device according to claim 3, characterized in that, the sealing resin has a top surface facing the side opposite to the bottom surface in the first direction, the whole of the top surface is exposed to the outside.

5. The cooling structure of a semiconductor device according to claim 4, characterized in that, when observed in the first direction, the periphery of the second surface includes an interval that is a convex curve.

6. The cooling structure of a semiconductor device according to claim 5, characterized in that, the bonding material has an end surface facing a direction orthogonal to the first direction, the end surface bulges outwards of the bonding material.

7. The cooling structure of a semiconductor device according to claim 6, characterized in that, the semiconductor element is electrically joined to the conductive layer.

8. The cooling structure of a semiconductor device according to claim 7, characterized in that, the dimension of the conductive layer in the first direction is larger than the dimension of the substrate in the first direction.

9. The cooling structure of a semiconductor device according to claim 8, characterized in that, the semiconductor device includes a first input terminal and a second input terminal electrically connected to the conductive layer, the first input terminal and the second input terminal respectively have exposed portions exposed from the sealing resin, when observed in the first direction, the exposed portions are separated from the cooler and the bonding material.

10. The cooling structure of a semiconductor device according to any one of claims 1 to 9, characterized in that, the substrate has an insulating layer, a metal layer laminated on the insulating layer, and a heat dissipation layer located on the side opposite to the insulating layer and laminated on the insulating layer, the conductive layer is joined to the metal layer, the first surface contacts the heat dissipation layer.

11. The cooling structure of a semiconductor device according to claim 10, characterized in that, The dimension of the bonding material in the first direction is smaller than the dimension of the heat dissipation layer in the first direction.

12. The cooling structure of a semiconductor device according to claim 10, wherein, the cooler has a housing that contacts the second surface, the housing has a hollow portion located inside the housing, and an inlet and an outlet that communicate with the hollow portion respectively, when observed in the first direction, the conductive layer overlaps with the hollow portion.

13. The cooling structure of a semiconductor device according to claim 12, wherein, the hollow portion includes a rapid constriction portion, and the cross-sectional area of the rapid constriction portion is the smallest in the direction orthogonal to the first direction and in the section from the inlet to the outlet, when observed in the first direction, the conductive layer overlaps with the rapid constriction portion.

14. The cooling structure of a semiconductor device according to claim 13, wherein, the cooler has a heat sink that is received in the rapid constriction portion and is connected to the housing, when observed in the first direction, the conductive layer overlaps with the heat sink.

15. The cooling structure of a semiconductor device according to claim 14, wherein, the heat sink includes a plurality of fins, the plurality of fins extend respectively in the direction orthogonal to the first direction and along the section from the inlet to the outlet.

16. The cooling structure of a semiconductor device according to claim 10, wherein, the cooler has: a base that contacts the second surface; and a heat dissipation portion that is located on the side opposite to the substrate with reference to the base and protrudes in the first direction from the base, the heat dissipation portion is exposed to the outside, when observed in the first direction, the conductive layer overlaps with the heat dissipation portion.

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