Semiconductor Device

Abstract

To provide a cooling unit and a semiconductor device capable of efficiently cooling each of a plurality of semiconductor packages.SOLUTION: A semiconductor device comprises: a plurality of semiconductor packages each having a first heat radiation plate and a second heat radiation plate opposite to the first heat radiation plate; a plurality of multihole pipes each having a flow channel for flowing a heating / cooling medium and extending in a first direction; and a plurality of bonding members provided between any one of the plurality of semiconductor packages and any one of the plurality of multihole pipes. A first multihole pipe provided at one end in a second direction in the plurality of multihole pipes is bonded with the first heat radiation plate in a first semiconductor package in the plurality of semiconductor packages via a first outside bonding member in the plurality of bonding members. The second heat radiation plate of the first semiconductor package is provided with a first inside bonding member. The first outside bonding member has a heat resistance lower than that of the first inside bonding member.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] In order to prevent the temperature of the power semiconductor package from rising due to heat generation, a multi-hole pipe through which a coolant flows is used.

[0003] Patent document 1 discloses a semiconductor device that cools by positioning the lower arm, which has a smaller thermal resistance, downstream of the coolant flow, thereby mitigating the increase in semiconductor chip temperature on the downstream side compared to the upstream side. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-228638 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a power semiconductor package that has heat generating surfaces on both sides and that is cooled on both sides, it is required to efficiently cool both sides of the power semiconductor package.

[0006] The present disclosure provides a semiconductor device that efficiently cools both sides of each of a plurality of semiconductor packages. [Means for solving the problem]

[0007] According to one aspect of the present disclosure, a heat sink device includes a first heat sink plate, a plurality of semiconductor packages having a second heat sink plate opposite to the first heat sink plate, a plurality of multi-hole tubes having a flow path extending in a first direction for flowing a thermal coolant, and a plurality of joining members provided between any of the plurality of semiconductor packages and any of the plurality of multi-hole tubes, wherein each of the plurality of multi-hole tubes is arranged side by side and spaced apart in a second direction perpendicular to the first direction, each of the plurality of semiconductor packages is provided between adjacent ones of the multi-hole tubes, and a first multi-hole tube provided at one end of the plurality of multi-hole tubes in the second direction is connected to the plurality of multi-hole tubes via a first outer joining member of the plurality of joining members. A semiconductor device is provided in which a first multi-hole tube is joined to a first heat sink of a first semiconductor package among the semiconductor packages, a first inner bonding member is provided on the second heat sink of the first semiconductor package, a second multi-hole tube provided at the other end in the second direction of the plurality of multi-hole tubes is joined to the second heat sink of a second semiconductor package among the plurality of semiconductor packages via a second outer bonding member of the plurality of bonding members, a second inner bonding member is provided on the first heat sink of the second semiconductor package, the first outer bonding member has a lower thermal resistance than the first inner bonding member, and the second outer bonding member has a lower thermal resistance than the second inner bonding member. Effect of the Invention

[0008] According to the semiconductor device of each of the embodiments of the present invention, both sides of each of the multiple semiconductor packages can be efficiently cooled. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of the semiconductor device of the present embodiment. [Diagram 2] FIG. 2 is an exploded perspective view of the semiconductor device of the present embodiment. [Diagram 3] FIG. 3 is a top view of the semiconductor package of the semiconductor device of the present embodiment. [Figure 4] FIG. 4 is a bottom view of the semiconductor package of the semiconductor device of the present embodiment. [Diagram 5]FIG. 5 is a perspective view of the cooler of the semiconductor device of the present embodiment. [Figure 6] FIG. 6 is an exploded perspective view of the cooler of the semiconductor device of the present embodiment. [Figure 7] FIG. 7 is a perspective view of a header of the cooler of the semiconductor device of the present embodiment. [Figure 8] FIG. 8 is a side view of the multi-hole pipe of the cooler of the semiconductor device of the present embodiment. [Figure 9] FIG. 9 is a cross-sectional view of the semiconductor device of the present embodiment. [Figure 10] FIG. 10 is a cross-sectional view of the semiconductor device of the present embodiment. [Figure 11] FIG. 11 is a side view of the inside of the semiconductor package of the semiconductor device of this embodiment. [Figure 12] FIG. 12 is an enlarged cross-sectional view of a portion of the semiconductor device of this embodiment. [Figure 13] FIG. 13 is a diagram illustrating the evaluation results of the semiconductor device of this embodiment. [Figure 14] FIG. 14 is a diagram illustrating the evaluation results of the semiconductor device of the comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, each embodiment of the present invention will be described with reference to the accompanying drawings. Note that, in the description of the specification and drawings relating to each embodiment, components having substantially the same or corresponding functional configurations may be given the same reference numerals to avoid redundant description. In addition, in order to facilitate understanding, the scale of each part in the drawings may differ from the actual scale.

[0011] In the directions of parallel, right angle, orthogonal, horizontal, vertical, up / down, left / right, etc., deviations are permitted to the extent that they do not impair the effects of the embodiment. The shape of the corners is not limited to right angles and may be rounded in an arch shape. Parallel, right angle, orthogonal, horizontal, and vertical may include approximately parallel, approximately right angle, approximately orthogonal, approximately horizontal, and approximately vertical.

[0012] <Semiconductor device 1> Fig. 1 is a perspective view of the semiconductor device 1 of this embodiment. Fig. 2 is an exploded perspective view of the semiconductor device 1 of this embodiment. The semiconductor device 1 is, for example, a power converter that converts direct current into alternating current using two semiconductor packages 20 and supplies power to each phase of a three-phase motor. The semiconductor device 1 is used, for example, in a power converter that drives a motor.

[0013] In addition, for convenience of explanation, an XYZ Cartesian coordinate system may be set in the drawings. For the coordinate axis perpendicular to the paper surface of the drawing, a cross mark in a circle on the coordinate axis indicates that the direction toward the back of the paper surface is positive, and a black circle mark in a circle indicates that the direction toward the front of the paper surface is positive. However, this coordinate system is defined for the purpose of explanation and does not limit the attitude of the semiconductor device 1, etc.

[0014] In this disclosure, unless otherwise specified, the X-axis is the extension direction of the first multi-hole tube 30b1, the second multi-hole tube 30b2, and the third multi-hole tube 30b3 of the cooler 30. The Y-axis is the direction in which the first multi-hole tube 30b1, the second multi-hole tube 30b2, and the third multi-hole tube 30b3 of the cooler 30 are adjacent to each other. The Y-axis direction may be referred to as the up-down direction. The Z-axis is the direction perpendicular to the X-axis and Y-axis.

[0015] The semiconductor device 1 includes a plurality of semiconductor packages 20 and a cooler 30.

[0016] The semiconductor device 1 of this embodiment includes six semiconductor packages 20. Specifically, the semiconductor device 1 includes a semiconductor package 21, a semiconductor package 22, a semiconductor package 23, a semiconductor package 24, a semiconductor package 25, and a semiconductor package 26. In the following description, when there is no need to distinguish between the semiconductor package 21, the semiconductor package 22, the semiconductor package 23, the semiconductor package 24, the semiconductor package 25, and the semiconductor package 26, they may be collectively referred to as the semiconductor package 20.

[0017] The semiconductor packages 20 are arranged and held in three rows and two columns between a first multi-hole pipe 30b1, a second multi-hole pipe 30b2, and a third multi-hole pipe 30b3 of the cooler 30, which will be described later. A coolant (heat coolant), for example, cooling water, is introduced into the cooler 30 from a coolant inlet 30ap1. The coolant introduced into the cooler 30 is discharged from a coolant outlet 30ap2. The semiconductor packages 20 are cooled by exchanging heat with the cooling water flowing through the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3.

[0018] Between the first multi-hole pipe 30b1 and the second multi-hole pipe 30b2, the semiconductor package 21, the semiconductor package 22, and the semiconductor package 23 are arranged in this order from the first header 30a side. The first multi-hole pipe 30b1 and the second multi-hole pipe 30b2 sandwich the semiconductor package 21, the semiconductor package 22, and the semiconductor package 23.

[0019] Further, between the second multi-hole pipe 30b2 and the third multi-hole pipe 30b3, the semiconductor package 24, the semiconductor package 25, and the semiconductor package 26 are arranged in this order from the first header 30a side. The second multi-hole pipe 30b2 and the third multi-hole pipe 30b3 sandwich the semiconductor package 24, the semiconductor package 25, and the semiconductor package 26.

[0020] The semiconductor package 20 and the cooler 30 of the semiconductor device 1 will now be described in detail.

[0021] <Semiconductor Package 20> Fig. 3 is a top view of the semiconductor package 20 of the semiconductor device 1 of this embodiment. Fig. 4 is a bottom view of the semiconductor package 20 of the semiconductor device 1 of this embodiment.

[0022] The semiconductor package 20 is, for example, a so-called 2-in-1 semiconductor package in which two semiconductor elements constituting upper and lower arms for one phase are packaged. The semiconductor package 20 is also a so-called double-sided cooling type semiconductor package. The semiconductor package 20 contains semiconductor elements such as power transistors, for example, IGBTs (Insulated Gate Bipolar Transistors) and FETs (Field-Effect Transistors).

[0023] The built-in semiconductor element may be a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor) or an FWD (Free Wheeling Diode). The mounted semiconductor element may be a RB-IGBT (Reverse Blocking-Insulated Gate Bipolar Transistor) in which the above-mentioned IGBT or FWD is integrated into a single chip. The mounted semiconductor element may be a RC-IGBT (Reverse Conducting-Insulated Gate Bipolar Transistor) in which the above-mentioned IGBT or FWD is integrated into a single chip.

[0024] The semiconductor package 20 includes a case 20d having a substantially rectangular parallelepiped shape and made of resin, for example, epoxy resin, etc. The case 20d has an upper surface 20dA and a lower surface 20dB on the opposite side to the upper surface 20dA.

[0025] The semiconductor package 20 has current terminals 20a1, 20a2, and 20a3, and control terminals 20b1, 20b2, 20b3, and 20b4 on a side surface of the case 20d. The current terminals 20a1, 20a2, and 20a3, and the control terminals 20b1, 20b2, 20b3, and 20b4 are provided to protrude from the side surface of the case 20d of the semiconductor package 20.

[0026] The current terminal 20a1, the current terminal 20a2, and the current terminal 20a3 are, for example, terminals for passing a current to a load. The current terminal 20a1, the current terminal 20a2, and the current terminal 20a3 are formed of a conductive material. The control terminal 20b1, the control terminal 20b2, the control terminal 20b3, and the control terminal 20b4 are terminals for controlling a current to be passed to a load. The control terminal 20b1, the control terminal 20b2, the control terminal 20b3, and the control terminal 20b4 are formed of a conductive material.

[0027] The semiconductor package 20 also has a heat sink 20c1 and a heat sink 20c2. For example, a power transistor built into the semiconductor package 20 is a heat generating element and therefore needs to be cooled. The heat sink 20c1 and the heat sink 20c2 are provided to dissipate heat from the heat generating element. The heat sink 20c1 and the heat sink 20c2 are made of a material with high thermal conductivity, for example, a metal such as copper. The heat sink 20c1 and the heat sink 20c2 are thermally connected to the heat generating element. The heat sink 20c1 is provided on an upper surface 20dA of the case 20d. The heat sink 20c2 is provided on a lower surface 20dB of the case 20d.

[0028] <Cooler 30> Fig. 5 is a perspective view of the cooler 30 of the semiconductor device 1 of the present embodiment. Fig. 6 is an exploded perspective view of the cooler 30 of the semiconductor device 1 of the present embodiment.

[0029] The cooler 30 cools the semiconductor package 20. A refrigerant flows through the inside of the cooler 30. The cooler 30 cools the semiconductor package 20 by exchanging heat between the semiconductor package 20 and a refrigerant (e.g., cooling water) flowing through the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3. The refrigerant is not limited to water, and may be a liquid including an antifreeze.

[0030] The cooler 30 includes a first header 30a, a first multi-hole pipe 30b1, a second multi-hole pipe 30b2, a third multi-hole pipe 30b3, and a second header 30c. The second header 30c is provided spaced apart from the first header 30a in the X-axis direction. The first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 are provided at predetermined intervals in the Y-axis direction, i.e., a direction intersecting the X-axis direction, specifically, at intervals that can hold the semiconductor package 20.

[0031] The X-axis direction is an example of the second direction.

[0032] The first header 30a is connected to one end of each of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3. Specifically, the first header 30a is connected to the -X side end of each of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3. The second header 30c is connected to the other end of each of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3. Specifically, the second header 30c is connected to the +X side end of each of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3.

[0033] [First header 30a] First, the first header 30a will be described. Fig. 7 is a perspective view of the first header 30a of the cooler 30 of the semiconductor device 1 of this embodiment. The first header 30a introduces the refrigerant into the inside of the cooler 30 and discharges it to the outside of the cooler 30. The first header 30a is a hollow rectangular parallelepiped formed by wall portions 30aA, 30aB, 30aC, 30aD, 30aE, and 30aF.

[0034] A part of the wall 30aE, which is the wall on the +X side of the first header 30a, is released. Specifically, the first header 30a has an opening 30ah1, an opening 30ah2, and an opening 30ah3 in the wall 30aE. One ends of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 are inserted into the openings 30ah1, 30ah2, and 30ah3 of the first header 30a, respectively, and fixed thereto. The first header 30a and the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 are fixed to each other by brazing, for example, to ensure watertightness.

[0035] The first header 30a has a refrigerant inlet 30ap1 and a refrigerant outlet 30ap2 in the wall portion 30aF. The refrigerant inlet 30ap1 introduces a refrigerant from an external cooling device. The refrigerant outlet 30ap2 discharges the refrigerant to the external cooling device. The first header 30a has a partition wall therein, which will be described later. The partition wall is a wall that separates the refrigerant introduced into the first header 30a from the refrigerant discharged from the first header 30a. The partition wall will be described in detail later.

[0036] [First multi-hole pipe 30b1, second multi-hole pipe 30b2, third multi-hole pipe 30b3] Next, the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 will be described. Fig. 8 is a side view of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 of the cooler 30 of the semiconductor device 1 of this embodiment. The first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 are pipes whose longitudinal ends are open and through which a refrigerant flows. The first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 cool the semiconductor package 20 by exchanging heat with the refrigerant flowing through the inside of the multi-hole pipe.

[0037] The first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 have a substantially rectangular cross section in the short side direction. The first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 are so-called microchannels having divided flow paths 30bc inside.

[0038] Each of the flow paths 30bc of the first multi-hole tube 30b1, the second multi-hole tube 30b2, and the third multi-hole tube 30b3 is a rectangular microchannel that is long in the Y-axis direction (up and down direction). The flow paths 30bc may be divided into two or more stages in the Y-axis direction.

[0039] The Y-axis direction (up-down direction) is an example of the first direction.

[0040] The first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 have a cooling surface 30bA and a cooling surface 30bB. When the semiconductor package 20 is cooled by the cooler 30, the semiconductor package 20 to be cooled is provided in contact with the cooling surface 30bA or the cooling surface 30bB. Specifically, the cooling surface 30bA or the cooling surface 30bB is thermally joined to the heat sink 20c1 or the heat sink 20c2 of the semiconductor package 20 by a joining member such as soldering or thermal conductive grease, which will be described later. The cooling surface 30bA and the cooling surface 30bB are mounting surfaces on which the heat sink 20c1 or the heat sink 20c2 of the semiconductor package 20 is mounted.

[0041] The flow paths 30bc of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 have a uniform cross-sectional area in the extending direction of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3. The extending direction of the flow paths 30bc of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 and the flow direction of the refrigerant are the same in the X-axis direction. In this disclosure, the cross-sectional area of ​​the flow path 30bc is the cross-sectional area of ​​a plane perpendicular to the extending direction of the flow paths 30bc, i.e., the flow direction of the refrigerant.

[0042] At least one of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 allows the refrigerant to flow in the direction from the first header 30a to the second header 30c, and the remaining multi-hole pipes allow the refrigerant to flow in the direction from the second header 30c to the first header 30a. In the following description, the multi-hole pipe through which the refrigerant flows in the direction from the first header 30a to the second header 30c may be referred to as the upstream multi-hole pipe, and the multi-hole pipe through which the refrigerant flows in the direction from the second header 30c to the first header 30a may be referred to as the downstream multi-hole pipe.

[0043] The number of multi-hole pipes is not limited to three, and may be, for example, two or four or more. In order to sandwich the semiconductor package 20, the cooler has at least two multi-hole pipes.

[0044] [Second Header 30c] The second header 30c guides the refrigerant introduced from at least one of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 to the remaining multi-hole pipes of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3. In other words, the second header 30c guides the refrigerant introduced from the upstream multi-hole pipe to the downstream multi-hole pipe.

[0045] The second header 30c is hollow with one side open. Specifically, the second header 30c has an opening 30ch1, an opening 30ch2, and an opening 30ch3 on the -X side surface. The other ends of the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 are inserted and fixed to the open side of the second header 30c. Specifically, the other end of the first multi-hole pipe 30b1 is inserted and fixed to the opening 30ch1. The other end of the second multi-hole pipe 30b2 is inserted and fixed to the opening 30ch2. The other end of the third multi-hole pipe 30b3 is inserted and fixed to the opening 30ch3. The second header 30c, the first multi-hole pipe 30b1, the second multi-hole pipe 30b2, and the third multi-hole pipe 30b3 are fixed to each other by brazing, for example, to ensure watertightness.

[0046] <Partition wall of first header 30a> Here, the partition walls provided in the first header 30a will be described.

[0047] The coolant introduced into the cooler 30 from an external cooling device absorbs heat from the semiconductor package 20 and is discharged from the cooler 30. Therefore, the temperature of the coolant flowing through the cooler 30 is lowest immediately after it is introduced, and gradually increases as it absorbs heat. In other words, the temperature of the coolant in the downstream multi-hole pipe is higher than the temperature of the coolant flowing through the upstream multi-hole pipe.

[0048] Next, the position of the partition wall provided in the first header 30a will be described. In the semiconductor device 1 of this embodiment, two multi-hole pipes, the first multi-hole pipe 30b1 and the second multi-hole pipe 30b2, are upstream multi-hole pipes. Also, one multi-hole pipe, the third multi-hole pipe 30b3, is downstream multi-hole pipe.

[0049] 9 and 10 are cross-sectional views of the semiconductor device 1 of this embodiment. Specifically, Fig. 9 is a cross-sectional view of the semiconductor device 1 cut at the first header 30a portion along a plane perpendicular to the X-axis direction. Specifically, Fig. 10 is a cross-sectional view of the semiconductor device 1 cut at the center portion in the Z direction along a plane perpendicular to the Z-axis direction. Note that the semiconductor package 20 is shown as a uniform cross section with internal details omitted.

[0050] In the semiconductor device 1 of this embodiment, the partition wall 30aw is provided so that the first multi-hole pipe 30b1 and the second multi-hole pipe 30b2 are upstream multi-hole pipes and the third multi-hole pipe 30b3 is downstream multi-hole pipe. The partition wall 30aw extends in the X-axis direction from the wall portion 30aF to the wall portion 30aE of the first header 30a.

[0051] The first multi-hole pipe 30b1 and the second multi-hole pipe 30b2 communicate with a space SPin surrounded by a part of the wall 30aA, the wall 30aB, a part of the wall 30aC, the partition wall 30aw, the wall 30aE, and the wall 30aF. A refrigerant is introduced into the space SPin from the refrigerant inlet 30ap1. The refrigerant introduced into the space SPin is discharged from the first multi-hole pipe 30b1 and the second multi-hole pipe 30b2 which communicate with the space SPin.

[0052] On the other hand, the third multi-hole pipe 30b3 communicates with a space SPout surrounded by a part of the wall 30aA, the partition wall 30aw, a part of the wall 30aC, the wall 30aD, the wall 30aE, and the wall 30aF. The refrigerant is introduced from the third multi-hole pipe 30b3 communicating with the space SPout. The refrigerant introduced into the space SPout is discharged from the refrigerant outlet 30ap2.

[0053] <Heat transfer> Fig. 11 is a side view showing the inside of the semiconductor package 20. Specifically, Fig. 11 is a view in which case 20d of the semiconductor package 20 is removed. Furthermore, Fig. 11 is a view in which current terminals 20a1, 20a2, and 20a3, and control terminals 20b1, 20b2, 20b3, and control terminals 20b4 are removed.

[0054] The semiconductor package 20 includes therein one or more semiconductor elements 20e, an insulating substrate 20f, an insulating substrate 20g, and one or more connection members 20h that connect between each of the one or more semiconductor elements 20e and the insulating substrate 20f.

[0055] The semiconductor element 20e is a semiconductor element such as a power transistor, such as an IGBT or a FET, etc. The semiconductor element 20e generates heat during operation.

[0056] The insulating substrate 20f includes a heat dissipation layer 20fa, a conductive layer 20fb, and an insulating layer 20fc. The heat dissipation layer 20fa is disposed on the outer side of the semiconductor package 20 with respect to the insulating layer 20fc. A heat sink 20c1 is provided on the heat dissipation layer 20fa. The conductive layer 20fb is disposed on the inner side of the semiconductor package 20 with respect to the insulating layer 20fc. A connecting member 20h is connected to the heat dissipation layer 20fa.

[0057] The insulating substrate 20g includes a heat dissipation layer 20ga, a conductive layer 20gb, and an insulating layer 20gc. The heat dissipation layer 20ga is disposed on the outer side of the semiconductor package 20 with respect to the insulating layer 20gc. A heat sink 20c2 is provided on the heat dissipation layer 20ga. The conductive layer 20gb is disposed on the inner side of the semiconductor package 20 with respect to the insulating layer 20gc. A semiconductor element 20e is placed on the heat dissipation layer 20ga. A connecting member 20h is connected to the semiconductor element 20e. The connecting member 20h connects the semiconductor element 20e and the insulating substrate 20f.

[0058] Heat generated by the semiconductor element 20e is dissipated from the heat sink 20c1 and the heat sink 20c2. A part of the heat from the semiconductor element 20e is propagated through the conductive layer 20gb, the insulating layer 20gc, and the heat sink 20ga in this order, and is dissipated from the heat sink 20c2. The path that propagates through the conductive layer 20gb, the insulating layer 20gc, and the heat sink 20ga in this order is referred to as a heat dissipation path HP1.

[0059] A part of the heat from the semiconductor element 20e is propagated through the connection member 20h, the conductive layer 20fb, the insulating layer 20fc, and the heat dissipation layer 20fa in this order, and is dissipated from the heat dissipation plate 20c1. The path that propagates through the connection member 20h, the conductive layer 20fb, the insulating layer 20fc, and the heat dissipation layer 20fa in this order is referred to as a heat dissipation path HP2.

[0060] Comparing the heat dissipation path HP1 and the heat dissipation path HP2, the path through which heat propagates is longer in the heat dissipation path HP2, and the heat is less likely to be transferred through the connecting member 20h. In other words, the thermal resistance of the heat dissipation path HP2 is higher than the thermal resistance of the heat dissipation path HP1.

[0061] Next, the joining member will be described. Fig. 12 is an enlarged cross-sectional view of a part of the semiconductor device 1 of this embodiment.

[0062] The semiconductor device 1 includes a bonding member 41a, a bonding member 42a, and a bonding member 43a between the first multi-hole tube 30b1 and the semiconductor package 21, the semiconductor package 22, and the semiconductor package 23, respectively. The semiconductor device 1 also includes a bonding member 41b, a bonding member 42b, and a bonding member 43b between the second multi-hole tube 30b2 and the semiconductor package 21, the semiconductor package 22, and the semiconductor package 23, respectively.

[0063] Furthermore, the semiconductor device 1 includes a bonding member 44a, a bonding member 45a, and a bonding member 46a between the second multi-hole tube 30b2 and the semiconductor package 24, the semiconductor package 25, and the semiconductor package 26, respectively. The semiconductor device 1 also includes a bonding member 44b, a bonding member 45b, and a bonding member 46b between the third multi-hole tube 30b3 and the semiconductor package 24, the semiconductor package 25, and the semiconductor package 26, respectively.

[0064] In addition, the joining members 41a and the like will be collectively referred to as the joining members 40 when there is no need to distinguish between them.

[0065] The joining member 40 is, for example, solder or thermally conductive grease. The joining member 40 thermally joins the semiconductor package and the multi-hole pipe. That is, the multi-hole pipe is joined to the heat sink of the semiconductor package via the joining member 40. The joining member 40 may also mechanically join the semiconductor package and the multi-hole pipe. If there is a gap between the semiconductor package and the multi-hole pipe, the transfer of heat from the semiconductor package to the multi-hole pipe is hindered. Therefore, the semiconductor device 1 includes the joining member 40 between the semiconductor package and the multi-hole pipe.

[0066] The thermal resistance of the bonding member 40 when heat is transferred from the semiconductor package to the multi-hole tube varies depending on the type. The thermal resistance of the bonding member 40 when heat is transferred from the semiconductor package to the multi-hole tube also varies depending on the thickness. In the semiconductor device 1 of the present disclosure, the thermal resistance of each bonding member 40 is adjusted by adjusting the thermal conductivity and thickness of the bonding member 40, and the cooling efficiency when cooling is adjusted to be uniform between the semiconductor packages.

[0067] In the present disclosure, the bonding members 44b, 45b, and 46b provided between the semiconductor package 24, the semiconductor package 25, and the semiconductor package 26 and the third multi-hole tube 30b3 are assumed to have the same thickness. Also, the thickness of each of the bonding members 44b, 45b, and 46b is assumed to be t1.

[0068] Also, the bonding members 44a, 45a, and 46a provided between the semiconductor package 24, the semiconductor package 25, and the semiconductor package 26 and the second multi-hole pipe 30b2 respectively have the same thickness. Also, the thickness of each of the bonding members 44a, 45a, and 46a is t2.

[0069] In the present disclosure, the bonding members 41b, 42b, and 43b provided between the semiconductor package 21, the semiconductor package 22, and the semiconductor package 23 and the second multi-hole tube 30b2 are assumed to have the same thickness. Also, the thickness of each of the bonding members 41b, 42b, and 43b is assumed to be t3.

[0070] Also, the bonding members 41a, 42a, and 43a provided between the semiconductor package 21, the semiconductor package 22, and the semiconductor package 23 and the first multi-hole pipe 30b1 respectively have the same thickness. Also, the thickness of each of the bonding members 41a, 42a, and 41a is t4.

[0071] Comparing the first multi-hole tube 30b1, the second multi-hole tube 30b2, and the third multi-hole tube 30b3, the number of semiconductor packages 20 connected to the second multi-hole tube 30b2 is greater than that of the first multi-hole tube 30b1 or the third multi-hole tube 30b3. Therefore, in order to achieve uniform cooling, it is desirable to reduce the amount of heat transferred from the semiconductor packages 20 connected to the second multi-hole tube 30b2 to the second multi-hole tube 30b2, and transfer the reduced amount of heat to the first multi-hole tube 30b1 or the third multi-hole tube 30b3.

[0072] In the semiconductor device 1 of the present disclosure, the thermal resistance of the joint member 40 between the semiconductor package 20 connected to the second multi-hole pipe 30b2 and the second multi-hole pipe 30b2 is increased.

[0073] Specifically, the thermal resistance of bonding members 41b, 42b and 43b between the second multi-hole tube 30b2 and the semiconductor package 21, semiconductor package 22 and semiconductor package 23, which are the semiconductor package 20 connected to the second multi-hole tube 30b2, is increased.

[0074] Specifically, the thermal resistance of bonding members 44a, 45a and 46a between the second multi-hole tube 30b2 and semiconductor package 24, semiconductor package 25 and semiconductor package 26, which are semiconductor packages 20 connected to the second multi-hole tube 30b2, is increased.

[0075] In order to increase the thermal resistance of the bonding members 40, for example, a member having a low thermal conductivity is used as the bonding members 40. In addition, in order to increase the thermal resistance of the bonding members 40, for example, the thickness of the bonding members 40 is increased.

[0076] Furthermore, the thermal resistance of the joint members 41a, 42a and 43a between the first multi-hole tube 30b1 and the semiconductor package 21, semiconductor package 22 and semiconductor package 23, which are the semiconductor package 20 connected to the first multi-hole tube 30b1, is reduced.

[0077] Specifically, the thermal resistance of bonding members 44b, 45b and 46b between the third multi-hole tube 30b3 and semiconductor package 24, semiconductor package 25 and semiconductor package 26, which are semiconductor packages 20 connected to the third multi-hole tube 30b3, is reduced.

[0078] In order to reduce the thermal resistance of the bonding members 40, for example, a member with high thermal conductivity is used as the bonding members 40. In addition, in order to reduce the thermal resistance of the bonding members 40, for example, the thickness of the bonding members 40 is reduced.

[0079] Furthermore, as described above, when the thermal resistance from the heat generating element to the heat sink 20c1 or the heat sink 20c2 is different inside the semiconductor package 20, the thermal resistance of the bonding member 40 connected to the heat sink 20c1 or the heat sink 20c2 is made different. For example, when the thermal resistance from the heat generating element to the heat sink 20c2 is smaller than the thermal resistance from the heat generating element to the heat sink 20c1, the thermal resistance of the bonding member 40 connected to the heat sink 20c2 is made larger than the thermal resistance of the bonding member 40 connected to the heat sink 20c1.

[0080] Specifically, the effect of adjusting the thermal resistance of the joining member will be described.

[0081] Fig. 13 is a diagram for explaining the evaluation results of the semiconductor device 1 of this embodiment. Specifically, the results are obtained when the thickness t1 is 0.1 mm, the thickness t2 is 1.6 mm, the thickness t3 is 1.0 mm, and the thickness t4 is 0.7 mm, with the thermal conductivity being constant at about 1.5 W / m·K. Fig. 14 is a diagram for explaining the evaluation results of the semiconductor device of the comparative example. Specifically, the results are obtained when the thicknesses t1, t2, t3, and t4 are each 0.85 mm.

[0082] 13 and 14, the heating element 1 is a semiconductor package 20 provided between the first multi-hole tube 30b1 and the second multi-hole tube 30b2. The heating element 2 is a semiconductor package 20 provided between the second multi-hole tube 30b2 and the third multi-hole tube 30b3. The lower side represents the first multi-hole tube 30b1 side, and the upper side represents the third multi-hole tube 30b3 side.

[0083] The thermal resistance from the heating element to the multi-hole pipe is the sum of the internal thermal resistance of the heating element itself, the thermal resistance of the joining member (jointing material), the thermal conduction resistance of the multi-hole pipe (multi-hole pipe thermal conduction resistance), and the heat transfer resistance inside the multi-hole pipe (average heat transfer resistance inside the pipe).

[0084] The thermal resistance inside each of the heating elements 1 and 2 may differ between when heat is dissipated from the upper heat sink and when heat is dissipated from the lower heat sink. Each of the heating elements 1 and 2 has a larger thermal resistance when heat is dissipated from the upper heat sink.

[0085] The multi-hole tube thermal conduction resistance is the thermal resistance when heat is conducted through the multi-hole tube, specifically, through the wall that constitutes the multi-hole tube. The average heat transfer resistance within the tube is the resistance when heat is transferred from the wall of the multi-hole tube to the refrigerant.

[0086] The average heat transfer resistance in the tube varies depending on the multi-hole tube due to the flow speed of the refrigerant flowing through the multi-hole tube. For example, comparing the first multi-hole tube 30b1, the second multi-hole tube 30b2, and the third multi-hole tube 30b3, the average heat transfer resistance in the tube of the third multi-hole tube 30b3 is lower than the average heat transfer resistance in the tube of the first multi-hole tube 30b1 and the second multi-hole tube 30b2.

[0087] In the semiconductor device 1 of this embodiment, the thermal resistance of the joining member is determined so that the amounts of heat transferred from the heat generating body 1 and the heat generating body 2 to the first multi-hole tube 30b1, the second multi-hole tube 30b2, and the third multi-hole tube 30b3 are equal. Specifically, the thermal resistance of the joining member is determined according to the thermal resistance on the heat sink 20c1 side and the thermal resistance on the heat sink 20c2 side of the semiconductor package 20 corresponding to the heat generating body 1 and the heat generating body 2. In addition, the thermal resistance of the joining member is determined according to the heat transfer resistance inside the multi-hole tube in which the semiconductor package 20 corresponding to the heat generating body 1 and the heat generating body 2 are mounted.

[0088] That is, the semiconductor package 20 is joined to the multi-hole pipe using a joining member having a thermal resistance corresponding to a first thermal resistance on the heat sink 20c1 side and a second thermal resistance on the heat sink 20c2 side inside the semiconductor package 20. The semiconductor package 20 is joined to the multi-hole pipe using a joining member having a thermal resistance corresponding to the in-pipe heat transfer resistance on the mounting surface side of the multi-hole pipe on which the heat sink 20c1 of the semiconductor package 20 is mounted and the in-pipe heat transfer resistance of the multi-hole pipe on which the heat sink 20c2 is mounted. Furthermore, the semiconductor package 20 is joined using a joining member having a thermal resistance corresponding to both the thermal resistance inside the semiconductor package 20 and the in-pipe heat transfer resistance of the multi-hole pipe to be mounted.

[0089] In the semiconductor device 1 of this embodiment, if the thermal resistance R1a on the lower side of the heating element 1 is 1, the thermal resistance R1b on the upper side of the heating element 1 is 2, the thermal resistance R2a on the lower side of the heating element 2 is 1.7, and the thermal resistance R2b on the upper side of the heating element 2 is 1.1.

[0090] Considering the above thermal resistance, the amounts of heat transfer input from the heating element 1 and the heating element 2 to each of the first multi-hole tube 30b1, the second multi-hole tube 30b2, and the third multi-hole tube 30b3 in the semiconductor device 1 of this embodiment are calculated. If the amount of heat transfer input to the first multi-hole tube 30b1 is 1, the amount of heat transfer input to the second multi-hole tube 30b2 is 1.1, and the amount of heat transfer input to the third multi-hole tube 30b3 is 0.9.

[0091] On the other hand, in the semiconductor device of the comparative example, if the thermal resistance R1a of the lower side of the heating element 1 is 1, the thermal resistance R1b of the upper side of the heating element 1 is 1.7, the thermal resistance R2a of the lower side of the heating element 2 is 1, and the thermal resistance R2b of the upper side of the heating element 2 is 1.6.

[0092] Taking the above thermal resistance into consideration, the amounts of heat transferred from the heat generating element 1 and the heat generating element 2 to each of the first multi-hole tube 30b1, the second multi-hole tube 30b2, and the third multi-hole tube 30b3 in the semiconductor device of the comparative example are calculated. If the amount of heat transferred to the first multi-hole tube 30b1 is 1, the amount of heat transferred to the second multi-hole tube 30b2 is 1.5, and the amount of heat transferred to the third multi-hole tube 30b3 is 0.7.

[0093] As described above, the amount of heat transferred to each of the first multi-hole tube 30b1, the second multi-hole tube 30b2, and the third multi-hole tube 30b3 can be made uniform in the semiconductor device 1. On the other hand, in the semiconductor device of the comparative example, the amount of heat transferred to the second multi-hole tube 30b2 was larger.

[0094] In addition, assuming that the first multi-hole pipe 30b1 is an example of a first multi-hole pipe provided at one end in the second direction and the third multi-hole pipe 30b3 is an example of a second multi-hole pipe provided at the other end in the second direction, the semiconductor package 22 is an example of a first semiconductor package, and the semiconductor package 25 is an example of a second semiconductor package. In addition, the bonding member 42a is an example of a first outer bonding member, the bonding member 42b is an example of a first inner bonding member, the bonding member 45a is an example of a second inner bonding member, and the bonding member 45b is an example of a second outer bonding member. In addition, the heat sink 20c1 and the heat sink 20c2 of the semiconductor package 20 are examples of a first heat sink and a second heat sink.

[0095] <Actions and Effects> The semiconductor device 1 of this embodiment can cool a plurality of semiconductor packages 20 evenly.

[0096] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0097] 1 Semiconductor device 20, 21, 22, 23, 24, 25, 26 Semiconductor packages 20c1, 20c2 heat sink 30 Cooler 30b1 1st multi-hole pipe 30b2 2nd multi-hole pipe 30b3 3rd multi-hole pipe 41a, 41b, 42a, 42b, 43a, 43b, 44a, 44b, 45a, 45b, 46a, 46b Joining members SPin space SPout space

Claims

1. a plurality of semiconductor packages each having a first heat sink and a second heat sink opposite the first heat sink; a plurality of multi-hole pipes each having a flow path extending in a first direction through which a thermal refrigerant flows; a plurality of joining members provided between any one of the plurality of semiconductor packages and any one of the plurality of multi-hole tubes; Equipped with The plurality of multi-hole tubes are arranged in a line and spaced apart relation in a second direction perpendicular to the first direction, Each of the plurality of semiconductor packages is provided between adjacent ones of the multi-hole tubes, A first multi-hole tube provided at one end in the second direction among the plurality of multi-hole tubes is joined to the first heat sink of a first semiconductor package among the plurality of semiconductor packages via a first outer joining member among the plurality of joining members, and a first inner joining member is provided on the second heat sink of the first semiconductor package, a second multi-hole tube provided at the other end in the second direction among the plurality of multi-hole tubes is joined to the second heat sink of a second semiconductor package among the plurality of semiconductor packages via a second outer joining member among the plurality of joining members, and a second inner joining member is provided on the first heat sink of the second semiconductor package; the first outer joint member has a lower thermal resistance than the first inner joint member; The second outer joint member has a lower thermal resistance than the second inner joint member. Semiconductor device.

2. a semiconductor package having a first heat sink and a second heat sink opposite the first heat sink; Two or more multi-hole tubes that sandwich the semiconductor package; Equipped with Among the two or more multi-hole tubes, one multi-hole tube has a first mounting surface on which the first heat sink is mounted, and the other multi-hole tube has a second mounting surface on which the second heat sink is mounted, The semiconductor package includes: the semiconductor package is joined to the multi-hole tube using a joining member having a thermal resistance corresponding to a first thermal resistance on the first heat sink side and a second thermal resistance on the second heat sink side inside the semiconductor package, and a thermal resistance corresponding to a heat transfer resistance inside the tube on the first mounting surface side and a heat transfer resistance inside the tube on the second mounting surface side; Semiconductor device.

3. the thermal conductivity of the first outer joint member is equal to the thermal conductivity of the first inner joint member; the first outer joint member is thinner than the first inner joint member; the thermal conductivity of the second outer joint member is equal to the thermal conductivity of the second inner joint member; The second outer joint member is thinner than the second inner joint member. The semiconductor device according to claim 1 .

4. The thickness of the first outer joint member is equal to the thickness of the first inner joint member, the thermal conductivity of the first outer joint member is higher than the thermal conductivity of the first inner joint member; The thickness of the second outer joint member is equal to the thickness of the second inner joint member, The thermal conductivity of the second outer joint member is higher than the thermal conductivity of the second inner joint member. The semiconductor device according to claim 1 .

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