JP2019186237A - Cooling device, semiconductor module and vehicle - Google Patents

Abstract

To suppress warpage of a cooling unit.SOLUTION: A cooling device for a semiconductor module including a semiconductor chip comprises: a top plate; a case part that includes a coolant circulation part, an outer edge part surrounding the coolant circulation part, and a bottom plate arranged so as to be opposed to the top plate, and in which the bottom plate has an upper surface opposed to the top plate and a lower surface opposite to the upper surface, and the coolant circulation part is arranged between a lower surface of the top plate and the upper surface of the bottom plate and arranged so as to be tightly adhered directly or indirectly to the lower surface of the top plate at the outer edge part; a cooling fin arranged in the coolant circulation part; and a reinforcement plate fixed to the lower surface of the bottom plate.SELECTED DRAWING: Figure 1A

Description

  The present invention relates to a cooling device, a semiconductor module, and a vehicle.

Conventionally, a configuration in which a cooling device is provided in a semiconductor module including a semiconductor element such as a power semiconductor chip is known (see, for example, Patent Documents 1-3).
Patent Literature 1 JP 2006-324647 A Patent Literature 2 JP 2010-93020 A Patent Literature 3 JP 2010-251443 A

  The cooler may warp in a mountain due to a difference in coefficient of linear expansion between the insulating substrate on which the semiconductor element is disposed and the cooling device.

  In order to solve the above-mentioned problems, in a first aspect of the present invention, a cooling device for a semiconductor module including a semiconductor chip is provided. The cooling device may include a top plate. The cooling device may include a case portion. The case part may have a refrigerant circulation part. The case part may have an outer edge part surrounding the refrigerant circulation part. The case portion may have a bottom plate disposed to face the top plate. The bottom plate may have an upper surface facing the top plate and a lower surface opposite to the upper surface. The refrigerant circulation part may be disposed between the lower surface of the top plate and the upper surface of the bottom plate. The case portion may be disposed in close contact with the lower surface of the top plate directly or indirectly at the outer edge portion. The cooling device may include cooling fins arranged in the refrigerant circulation part. The cooling device may include a reinforcing plate fixed to the lower surface of the bottom plate.

  The reinforcing plate may cover 90% or more of the lower surface of the bottom plate.

  The reinforcing plate may be larger than the bottom surface of the bottom plate in a plane parallel to the bottom surface of the bottom plate.

  The case portion may be provided integrally with the bottom plate, and may have a side wall that defines a refrigerant circulation portion between the top plate and the bottom plate. The ratio of the area where the reinforcing plate covers the lower surface of the bottom plate to the total area of the bottom surface of the bottom plate is larger than the ratio of the area where the reinforcing plate covers the side surface of the side wall to the total area of the side surfaces of the side wall. Good.

  The bottom plate may have a pair of opposed long sides and a set of opposed short sides in a top view. On the side wall connected to the short side of the bottom plate, a narrowed portion having a curved shape when viewed from above may be provided from the upper end to the lower end of the side wall. The throttle part does not need to be provided on the side wall connected to the long side of the bottom plate.

  The bottom plate may be provided with two bottom plate openings through which the refrigerant is introduced into or led out from the refrigerant circulation portion. The reinforcing plate may be provided with a reinforcing plate opening having a smaller opening area than the bottom plate opening at a position overlapping the bottom plate opening.

  The reinforcing plate may have a base portion fixed to the lower surface of the bottom plate. The reinforcing plate may be provided so as to protrude upward from the base portion and have a protrusion fixed to the side wall.

  The reinforcing plate may have a pair of opposed long sides and a set of opposed short sides in a top view. At least one protrusion may be provided on each side of the reinforcing plate. Two or more protrusions may be provided on at least one long side.

  A plurality of reinforcing plates may be laminated. The reinforcing plate may be formed of the same material as the case portion. The reinforcing plate may have the same thickness as the bottom plate of the case portion.

  According to a second aspect of the present invention, there is provided a semiconductor module comprising the cooling device according to the first aspect and a semiconductor device disposed above the top plate.

  According to a third aspect of the present invention, there is provided a vehicle including the semiconductor module according to the second aspect.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

It is a typical sectional view showing an example of semiconductor module 100 concerning one embodiment of the present invention. It is a figure showing semiconductor module 100 in the state where pipe 90 was connected. It is a figure which shows an example of the shape of the top plate 20 in a top view (xy surface). It is a figure which shows an example of the shape of the case part 40 in upper surface view (xy surface). It is a figure which shows an example of the shape of the reinforcement board 30 in upper surface view (xy surface). It is the perspective view which separated and showed the top plate 20, the case part 40, and the reinforcement board 30. FIG. FIG. 5 is a perspective view of the reinforcing plate 30 and the case portion 40 with the direction in the z-axis direction reversed. 6 is a top view showing another example of a reinforcing plate 30. FIG. FIG. 8 is a perspective view of a reinforcing plate 30 shown in FIG. 7. FIG. 6 is a bottom view showing another example of the case part 40. FIG. 6 is a perspective view of the vicinity of a throttle unit 44. It is a figure which shows an example of the reinforcement board opening part 43 and the baseplate opening part 42. FIG. FIG. 12 is a cross-sectional view of the bottom plate 64 and the reinforcing plate 30 in the vicinity of the reinforcing plate opening 43 and the bottom plate opening shown in FIG. 11. FIG. 6 is a cross-sectional view showing another example of the cooling device 10. It is a figure which shows the other example of the reinforcement board 30. FIG. It is a figure showing an outline of vehicle 200 concerning one embodiment of the present invention. 1 is a main circuit diagram of a semiconductor module 100 according to an embodiment of the present invention.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1A is a schematic cross-sectional view showing an example of a semiconductor module 100 according to an embodiment of the present invention. The semiconductor module 100 includes a semiconductor device 70 and a cooling device 10. The semiconductor device 70 of this example is disposed in the cooling device 10. In this specification, the surface of the cooling device 10 on which the semiconductor device 70 is disposed is defined as an xy plane, and a plane perpendicular to the xy plane is defined as a z-axis. In this specification, the direction from the cooling device 10 toward the semiconductor device 70 in the z-axis direction is referred to as “up”, and the opposite direction is referred to as “down”. However, the upper and lower directions are not limited to the gravity direction. In the present specification, among the surfaces of the members, the upper surface is referred to as the upper surface, the lower surface is referred to as the lower surface, and the surface between the upper surface and the lower surface is referred to as the side surface.

  The semiconductor device 70 includes one or more semiconductor chips 78 such as power semiconductor chips. As an example, the semiconductor chip 78 is provided with an insulated gate bipolar transistor (IGBT) formed on a semiconductor substrate such as silicon.

  The semiconductor device 70 includes a circuit board 76 and a housing portion 72. As an example, the circuit board 76 is a board in which a circuit pattern is provided on an insulating board. A semiconductor chip 78 is fixed to the circuit board 76 via solder or the like. The accommodating part 72 is formed with insulating materials, such as resin. The accommodating portion 72 has an internal space for accommodating the semiconductor chip 78, the circuit board 76, the wiring, and the like. The internal space of the accommodating portion 72 may be filled with a sealing portion 74 that seals the semiconductor chip 78, the circuit board 76, the wiring, and the like. The sealing portion 74 is an insulating member such as silicone gel or epoxy resin.

  The cooling device 10 includes a top plate 20 and a case portion 40. The top plate 20 may be a plate-shaped metal plate having an upper surface 22 and a lower surface 24 parallel to the xy plane. As an example, the top plate 20 is made of a metal containing aluminum. A semiconductor device 70 is disposed on the upper surface 22 of the top plate 20. Heat generated by the semiconductor chip 78 is transmitted to the top plate 20. For example, a thermally conductive member such as a circuit board 76, a metal plate, and solder is disposed between the top plate 20 and the semiconductor chip 78. The circuit board 76 may be directly fixed to the upper surface 22 of the top plate 20 with solder or the like. In this case, the accommodating portion 72 is provided so as to surround a region where the circuit board 76 and the like are disposed on the upper surface 22 of the top plate 20. In another example, the semiconductor device 70 has a metal plate exposed on the lower surface of the housing portion 72, the circuit board 76 is fixed to the upper surface of the metal plate, and the metal plate is fixed to the upper surface 22 of the top plate 20. May be.

  The case portion 40 includes a refrigerant circulation portion 92, an outer edge portion 41 that surrounds the refrigerant circulation portion 92, and a bottom plate 64 that is disposed to face the top plate 20. The bottom plate 64 has an upper surface 65 facing the top plate 20 and a lower surface 66 opposite to the upper surface 65. The refrigerant circulation part 92 is disposed between the lower surface 24 of the top plate 20 and the upper surface 65 of the bottom plate 64. The case part 40 may be formed integrally with the top plate 20 or may be formed as a separate member. The refrigerant circulation part 92 is an area through which a refrigerant such as water circulates. The refrigerant circulation part 92 may be a sealed space in contact with the lower surface 24 of the top plate 20. Moreover, the case part 40 is arrange | positioned in close contact with the lower surface 24 of the top plate 20 directly or indirectly in the outer edge part 41 which surrounds the refrigerant | coolant circulation part 92 in xy surface. Thereby, the refrigerant | coolant distribution part 92 is sealed. Indirect contact refers to the lower surface 24 of the top plate 20 and the case portion via a sealant, adhesive, or other member provided between the lower surface 24 of the top plate 20 and the case portion 40. 40 is in close contact. The close contact refers to a state in which the refrigerant inside the coolant circulation part 92 does not leak from the close contact portion.

  Cooling fins 94 are arranged inside the refrigerant circulation part 92. The cooling fin 94 may be connected to the lower surface 24 of the top plate 20. By passing the refrigerant in the vicinity of the cooling fin 94, the heat generated by the semiconductor chip 78 is transferred to the refrigerant. Thereby, the semiconductor device 70 can be cooled. The case portion 40 of this example has a frame portion 62, a bottom plate 64, and a side wall 63. The outer edge portion 41 may include at least a frame portion 62.

  The frame part 62 is disposed so as to surround the refrigerant circulation part 92 on the xy plane. The frame part 62 is disposed in close contact with the lower surface 24 of the top plate 20 directly or indirectly. That is, the frame part 62 and the lower surface 24 of the top plate 20 are provided so as to seal the refrigerant circulation part 92. A sealing material or another member may be provided between the frame portion 62 and the lower surface 24 of the top plate 20.

  In this example, the top plate 20 and the case portion 40 are brazed. As an example, the top plate 20 and the case portion 40 are made of a material having the same composition (in this example, metal), and the brazing material is made of a metal having a lower melting point than the top plate 20 or the like.

  The bottom plate 64 is disposed so as to face the top plate 20 in the z-axis direction and have a refrigerant circulation portion 92 between the bottom plate 24 and the lower surface 24 of the top plate 20. The bottom plate 64 may indicate a portion parallel to the top plate 20 among the portions of the case unit 40 that are arranged away from the top plate 20. The side wall 63 defines the coolant circulation part 92 by connecting the frame part 62 and the bottom plate 64. The bottom plate 64 has an upper surface 65 facing the top plate 20 and a lower surface 66 opposite to the upper surface 65. The side wall 63 extends from the bottom plate 64 toward the top plate 20. The bottom plate 64 of this example is provided with two or more bottom plate openings 42 through which the refrigerant is introduced into or led out from the refrigerant circulation portion 92. In another example, the bottom plate opening 42 may be provided in the side wall 63.

  The top plate 20 and the case portion 40 may be provided with through holes into which screws or the like for fastening each other are inserted. The through hole may be used to fix the semiconductor module 100 to an external device. The through hole is provided in a region where the top plate 20 and the frame portion 62 are directly or indirectly in close contact with each other and overlapped in the z-axis direction.

  The cooling fin 94 is provided between the two bottom plate openings 42. One bottom plate opening 42 provided with the cooling fins 94 interposed therebetween functions as an inlet for introducing the refrigerant into the refrigerant circulation portion 92, and the other bottom plate opening 42 extracts the refrigerant from the refrigerant circulation portion 92. It functions as a outlet. The user can appropriately select which bottom plate opening 42 functions as an inlet or outlet.

  The cooling device 10 further includes a reinforcing plate 30 fixed to the lower surface 66 of the bottom plate 64. The reinforcing plate 30 is a plate-like member provided so as to cover at least a part of the lower surface 66 of the bottom plate 64. The reinforcing plate 30 may cover 90% or more of the area of the lower surface 66 of the bottom plate 64, or may cover the whole. The reinforcing plate 30 may have the same shape as the lower surface 66 of the bottom plate 64. The reinforcing plate 30 may be larger than the lower surface 66 of the bottom plate 64.

  The reinforcing plate 30 may be formed of a metal having the same composition as the case portion 40. As an example, the reinforcing plate 30 is formed of a metal containing aluminum. As a metal containing aluminum, an aluminum alloy such as an Al—Mn alloy (3000 series aluminum alloy) or an Al—Mg—Si alloy (6000 series aluminum alloy) may be used. An aluminum alloy such as an Al—Si based alloy (4000 based aluminum alloy) may be used as the brazing material. The top plate 20 may also be formed of a metal having the same composition as the case portion 40. The reinforcing plate 30 may be formed of a material having a higher tensile strength than the top plate 20 and the case portion 40. As the tensile strength, a value obtained by dividing the maximum load when a tensile load is applied to a rod-shaped material having a uniform cross-sectional area to be broken by the cross-sectional area may be used.

  Providing the reinforcing plate 30 on the bottom plate 64 can suppress the cooling device 10 from warping in the z-axis direction. Further, by providing the reinforcing plate 30, the strength of the cooling device 10 can be improved without increasing the thickness of the entire case portion 40 (particularly, the thickness of the side wall 63). For this reason, when forging the side wall 63 and the like, the processing becomes easy.

  The reinforcing plate 30 of this example is disposed in parallel with the lower surface 66 of the bottom plate 64, and is provided with a base portion 32 fixed to the lower surface 66, protruding upward (in the z-axis direction) from the base portion 32, and fixed to the side wall 63. Projecting portion 34. The protrusions 34 are discretely arranged on the peripheral edge portion of the base portion 32 on the xy plane. The base part 32 and the protrusion part 34 may be integrally formed. That is, the base part 32 and the protrusion part 34 may be obtained by bending a single plate-like member.

  The base portion 32 may have a shape along the lower surface 66 of the bottom plate 64. When the lower surface 66 is a flat surface, the base portion 32 is preferably flat. When the unevenness is provided on the lower surface 66, the base portion 32 may have an unevenness along the lower surface 66. In the base portion 32 of this example, the entire portion overlapping the lower surface 66 is fixed in close contact with the lower surface 66.

  The reinforcing plate 30 is not provided on at least a part of the side wall 63. In the side wall 63 of this example, the reinforcing plate 30 is not fixed except for the protruding portion 34. Since the reinforcing plate 30 is not provided on most of the side wall 63, the side wall 63 is more easily deformed than the bottom plate 64. For this reason, even if the bottom plate 64 is slightly warped, the warp can be absorbed by the side wall 63 and the stress transmitted to the frame portion 62 can be reduced. For this reason, the adhesiveness of the frame part 62 and the top plate 20 can be maintained. Further, when the bottom plate opening 42 is provided in the bottom plate 64, the reinforcing plate 30 can be provided to reinforce a portion where a force is applied at the time of connecting a pipe 90 described later in FIG. 1B.

  When the bottom plate opening 42 is provided in the bottom plate 64, the reinforcing plate 30 is provided with the reinforcing plate opening 43 at a position overlapping the bottom plate opening 42. The refrigerant passes through both the bottom plate opening 42 and the reinforcing plate opening 43, and is introduced or led out to the refrigerant circulation portion 92.

  In this example, the members of the top plate 20, the case portion 40, and the reinforcing plate 30 are brazed. As an example, the top plate 20, the case portion 40, and the reinforcing plate 30 are made of a metal having the same composition, and the brazing material is made of a metal having a melting point lower than that of the top plate 20 or the like.

  FIG. 1B is a diagram illustrating the semiconductor module 100 with the pipe 90 connected thereto. The pipe 90 is fixed to the reinforcing plate 30 via a sealing material such as an O-ring. The pipe 90 introduces or leads the refrigerant to the refrigerant circulation part 92. The means for introducing or deriving the refrigerant to / from the refrigerant circulation unit 92 is not limited to the pipe 90.

  FIG. 2 is a diagram illustrating an example of the shape of the top plate 20 in a top view (xy plane). The top plate 20 has two sets of opposing sides 26 and 28 in a top view. The top plate 20 of this example has a substantially rectangular shape having a short side 26 and a long side 28. In this specification, the direction in which the short side 26 extends is the x axis, and the direction in which the long side 28 extends is the y axis.

  The top plate 20 has a through hole 82 which is a part of a through hole used for fastening the top plate 20 and the case portion 40 to each other or fixing the semiconductor module 100 to an external device, as described in FIG. 1A. Is provided. Although the through holes 82 of this example are provided at the four corners of the top plate 20, the position and number of the through holes 82 are not limited to this. Moreover, the shape of the top plate 20 is not limited to a rectangle as shown in FIG. The top plate 20 may have a portion protruding from each side in the xy plane. The through hole 82 may be provided in the protruding portion.

  FIG. 3 is a diagram illustrating an example of the shape of the case portion 40 in a top view (xy plane). The outer shape of the case portion 40 in this example on the xy plane is the same as the outer shape of the top plate 20. In this example, the outer shape of the frame portion 62 corresponds to the outer shape of the case portion 40. The cross section of the cooling device 10 shown in FIG. 1A corresponds to the AA cross section in FIG.

  A through hole 86 is also provided at each corner of the case portion 40 at a position corresponding to the through hole 82. In this example, a through hole 86 is provided in the frame portion 62.

  A bottom plate 64 is provided inside the frame portion 62 on the xy plane. The bottom plate 64 of this example is provided with two bottom plate openings 42. The bottom plate opening 42 in this example is disposed at two diagonals of the bottom plate 64, but the position of the bottom plate opening 42 is not limited to this.

  FIG. 4 is a diagram illustrating an example of the shape of the reinforcing plate 30 in a top view (xy plane). In the reinforcing plate 30 of this example, the base portion 32 has the same outer shape as the bottom plate 64. A plurality of protrusions 34 are discretely arranged along the periphery of the base portion 32.

  The reinforcing plate 30 of this example has two opposing short sides 36 that are parallel in the xy plane and two opposing long sides 38 that are parallel in the xy plane. The short side 36 and the long side 38 in this example are arranged at right angles. At least one protrusion 34 is disposed on each of the two short sides 36 and the two long sides 38. In addition, it is preferable that at least one long side 38 is provided with two or more protrusions 34.

  By arranging at least five protrusions 34 in this way, when the reinforcing plate 30 is fixed to the bottom plate 64 of the case portion 40, the reinforcing plate 30 is displaced or rotated with respect to the case portion 40. Can be prevented. As an example, the reinforcing plate 30 is brazed to the bottom plate 64 of the case portion 40. By providing the projecting portion 34, the reinforcing plate 30 can be prevented from moving when the brazing material is melted. The brazing material may be provided between the base portion 32 and the bottom plate 64 and between the protruding portion 34 and the side wall 63.

  In addition, the protrusion part 34 provided in the long side 38 may be provided in the position which does not oppose the protrusion part 34 provided in the long side 38 which opposes an x-axis direction. That is, the protrusion 34 provided on the long side 38 may be different in position on the y-axis from the protrusion 34 provided on the opposing long side 38. Thereby, it can suppress that the reinforcement board 30 rotates when a brazing material is fuse | melted. Further, the protrusion 34 provided on the short side 36 may be provided at a position that does not oppose the y-axis direction with respect to the protrusion 34 provided on the opposing short side 36, or may be provided at an opposite position. Good.

  In the reinforcing plate 30, a reinforcing plate opening 43 is provided at a position overlapping the bottom plate opening 42. The shape and size of the reinforcing plate opening 43 and the bottom plate opening 42 may be the same or different.

  The protrusion 34 provided on the long side 38 may be provided at a position that does not oppose the reinforcing plate opening 43 closest to the long side 38 in the x-axis direction. That is, the protrusion 34 provided on the long side 38 may be different in position in the y-axis direction from the reinforcing plate opening 43 closest to the long side 38. By avoiding the region where the width of the reinforcing plate 30 is narrowed by providing the reinforcing plate opening 43, by providing the protruding portion 34, the stress on the region can be relieved. The protrusion 34 provided on the long side 38 may be provided to face the reinforcing plate opening 43 farthest from the long side 38 in the x-axis direction.

  The protrusion 34 provided on the short side 36 may be provided at a position that does not oppose any reinforcing plate opening 43 in the y-axis direction. The protrusion 34 provided on the short side 36 may be disposed at the center of the short side 36.

  FIG. 5 is a perspective view showing the top plate 20, the case portion 40, and the reinforcing plate 30 separately. As described above, the top plate 20 and the case portion 40 may have substantially the same outer shape on the xy plane. The reinforcing plate 30 and the bottom plate 64 of the case portion 40 may have substantially the same outer shape on the xy plane. In FIG. 5, overlapping positions when the top plate 20, the case portion 40, and the reinforcing plate 30 are fixed by brazing or the like are indicated by broken lines. In FIG. 5, the cooling fins 94 disposed in the refrigerant circulation part 92 are omitted. Further, the brazing material between the members is also omitted.

  As shown in FIG. 5, the frame part 62 is disposed so as to surround the refrigerant circulation part 92, and seals the refrigerant circulation part 92 together with the top plate 20. The case portion 40 includes a bottom plate 64 disposed away from the top plate 20 and a side wall 63 that connects the bottom plate 64 and the frame portion 62. A refrigerant flow portion 92 is defined by the lower surface 24 of the top plate 20 and the case portion 40.

  Moreover, the top plate 20, the reinforcing plate 30, and the bottom plate 64 of the case portion 40 may have the same thickness. Further, the case portion 40 may be integrally provided with the frame portion 62 and the side wall 63. The frame part 62 and the side wall 63 may be formed by forging a single plate-like metal. Further, the bottom plate 64 may be provided integrally with the side wall 63, and may be brazed to the side wall 63. The bottom plate 64, the frame part 62, and the side wall 63 may have the same thickness. Since each member has the same thickness, the cooling device 10 can be manufactured using a common metal roll material.

  As described above, the reinforcing plate 30 is provided with the protruding portion 34 that protrudes upward (in the z-axis direction, the direction toward the top plate 20). The length of the protrusion 34 in the z-axis direction may be smaller than the height of the side wall 63 in the z-axis direction, or may be the same.

  FIG. 6 is a perspective view of the reinforcing plate 30 and the case portion 40 in which the direction in the z-axis direction is reversed from that in FIG. As described above, the reinforcing plate 30 may cover the entire lower surface 66 of the bottom plate 64 of the case portion 40. When the brazing material is provided on the entire lower surface 66 and the reinforcing plate 30 is fixed, covering the entire lower surface 66 with the reinforcing plate 30 can prevent the brazing material from being exposed or dripping.

  When the brazing material is provided on a part of the lower surface 66, the reinforcing plate 30 may cover the region where the brazing material is provided and may not cover at least a part of the region where the brazing material is not provided. . The brazing material may be provided on the reinforcing plate 30. An external member to be cooled may be brought into contact with the lower surface 66 exposed without being covered by the reinforcing plate 30.

  Further, most of the side wall 63 is not covered with the reinforcing plate 30. The ratio of the area where the reinforcing plate 30 (base portion 32 in this example) covers the lower surface 66 of the bottom plate 64 to the total area of the lower surface 66 of the bottom plate 64 is R1. Further, the ratio of the area where the reinforcing plate 30 (the projecting portion 34 in this example) covers the side surface 67 of the side wall 63 to the total area of the side surface 67 of the side wall 63 is R2. The ratio R1 is larger than the ratio R2. As an example, the ratio R1 may be 90% or more, and may be 100%. The ratio R2 may be 20% or less, may be 10% or less, and may be 0%.

  FIG. 7 is a top view showing another example of the reinforcing plate 30. In FIG. 6, the position overlapping the lower surface 66 of the bottom plate 64 is indicated by a dotted line. The reinforcing plate 30 of this example is larger than the lower surface 66 of the bottom plate 64. In the example shown in FIG. 4, the protruding portion 34 is provided to protrude outward from the long side 38 and the short side 36 of the reinforcing plate 30, but the protruding portion 34 in this example is the long side of the reinforcing plate 30. 38 and the short side 36 are provided inside.

  In the example of FIG. 7, the reinforcing plate 30 protrudes outward from the lower surface 66 over the entire outer periphery of the lower surface 66, but in another example, the reinforcing plate 30 is formed at a part of the outer periphery of the lower surface 66. It may protrude outward from the lower surface 66. Since the reinforcing plate 30 has a portion protruding outward from the lower surface 66, when the brazing material provided between the reinforcing plate 30 and the bottom plate 64 is melted, the brazing material can be prevented from drooping downward.

  FIG. 8 is a perspective view of the reinforcing plate 30 shown in FIG. Each protrusion 34 may be provided so that the side surfaces of the long side 38 and the short side 36 of the reinforcing plate 30 are flush with each other.

  FIG. 9 is a bottom view showing another example of the case portion 40. The case portion 40 of this example may be applied to any form described with reference to FIGS. 1A to 8. The bottom plate 64 of the case portion 40 of this example has a pair of opposed long sides 48 and a set of opposed short sides 46 in the xy plane. At least one side wall 63 connected to the short side 46 of the bottom plate 64 is provided with a throttle portion 44 having a curved shape in the xy plane.

  In the present example, the diaphragm portion 44 is provided for both short sides 46. A plurality of apertures 44 may be provided on each short side 46. In this example, the two throttle portions 44 are disposed so as to sandwich the protruding portion 34 of the reinforcing plate 30 in the x-axis direction. In FIG. 9, the position where the protrusion 34 is disposed is indicated by a broken line.

  FIG. 10 is a perspective view of the vicinity of the throttle portion 44. The throttle portion 44 is provided with a curved shape on the xy plane continuously from the upper end 52 to the lower end 54 of the side wall 63. The upper end 52 of the side wall 63 is a boundary between the frame portion 62 and the side wall 63, and the lower end 54 is a boundary between the bottom plate 64 and the side wall 63. The upper end 52 and the lower end 54 of the side wall 63 may be the upper end and the lower end of a range where the inclination of the side wall 63 is constant (for example, perpendicular to the top plate 20).

  By providing the throttle portion 44, the strength of the side wall 63 can be improved. Further, by providing the narrowed portion 44 so as to sandwich the protruding portion 34, a region where stress is easily applied can be sandwiched by the narrowed portion 44, and the strength of the side wall 63 can be further improved.

  Further, the throttle part 44 is not provided on the side wall 63 connected to the long side 48 of the bottom plate 64. In another example, the side wall 63 connected to the long side 48 may be provided with a curved portion having a larger radius of curvature than the throttle portion 44 in the xy plane. By not providing the narrowed portion 44 on the long side 48, a part of the warp in the z-axis direction of the bottom plate 64 can be absorbed by the long side 48.

  FIG. 11 is a diagram illustrating an example of the reinforcing plate opening 43 and the bottom plate opening 42. The reinforcing plate opening 43 and the bottom plate opening 42 of this example may be applied to any of the modes described with reference to FIGS. 1A to 10.

  As described above, the reinforcing plate opening 43 and the bottom plate opening 42 are provided at positions overlapping in the xy plane. In this example, the opening area of the reinforcing plate opening 43 is smaller than the opening area of the bottom plate opening 42. That is, the edge of the opening of the reinforcing plate opening 43 is arranged inside the edge of the opening of the bottom plate opening 42.

  12 is a cross-sectional view of the bottom plate 64 and the reinforcing plate 30 in the vicinity of the reinforcing plate opening 43 and the bottom plate opening 42 shown in FIG. In this example, a brazing material 56 is provided between the bottom plate 64 and the reinforcing plate 30.

  As described above, the edge 49 of the reinforcing plate opening 43 is disposed inside the edge 50 of the bottom plate opening 42 in the xy plane. When the reinforcing plate opening 43 is formed by punching or the like, burrs or the like protruding in the z-axis direction may be formed on the edge 49 of the reinforcing plate opening 43 in some cases.

  According to this example, even if a burr or the like is formed at the edge 49 of the reinforcing plate opening 43, the burr can be accommodated inside the bottom plate opening 42. For this reason, the fall of the adhesiveness of the baseplate 64 and the reinforcement board 30 by the said burr | flash can be suppressed. Further, since the reinforcing plate 30 protrudes to the inside of the bottom plate opening 42, it is possible to suppress the brazing material 56 from dripping. Further, according to this example, even if the position of the reinforcing plate 30 on the xy plane is shifted, the reinforcing plate opening 43 can be easily disposed at a position overlapping the bottom plate opening 42. The shape of the bottom plate opening 42 and the reinforcing plate opening 43 on the xy plane may be an oval shape such as a circle, an oval, a rounded square, or an ellipse. The shapes of the bottom plate opening 42 and the reinforcing plate opening 43 may be similar to each other.

  FIG. 13 is a cross-sectional view illustrating another example of the cooling device 10. In the cooling device 10 of this example, a plurality of reinforcing plates 30 are stacked in the z-axis direction. A structure in which a plurality of reinforcing plates 30 are laminated (in FIG. 13, the reinforcing plate 30-1 and the reinforcing plate 30-2) may be applied to any of the modes described in FIGS. 1A to 12. Each reinforcing plate 30 may have the same thickness. With such a structure, the strength of the bottom plate 64 can be further improved.

  Each reinforcing plate 30 is provided with a reinforcing plate opening 43. As the reinforcing plate 30 is farther from the bottom plate 64, the opening area of the reinforcing plate opening 43 may be smaller. Each reinforcement board opening part 43 may be arrange | positioned inside each opening part formed upwards in the z-axis direction.

  Further, each reinforcing plate 30 may be provided with a protruding portion 34. In this case, the projecting portions 34 of the respective reinforcing plates 30 are provided at positions where they do not contact the projecting portions 34 of the other reinforcing plates 30. In another example, the protrusion 34 may be provided only on the reinforcing plate 30 adjacent to the bottom plate 64.

  FIG. 14 is a diagram illustrating another example of the reinforcing plate 30. The reinforcing plate 30 of this example has the same shape as the top plate 20 in the xy plane. The reinforcing plate 30 of this example may be applied to any of the modes described with reference to FIGS. 1A to 13. Further, FIG. 14 schematically shows a through hole 79 used for fastening the top plate 20 and the case portion 40 to each other or fixing the semiconductor module 100 to an external device. The position of the through hole 79 is not limited to the position shown in FIG.

  In the reinforcing plate 30 of this example, a through hole 81 is provided at a position facing the through hole 79. A common fastening material such as a screw is inserted into the through hole 79 and the through hole 81. Thereby, the reinforcing plate 30 can be pressed against the bottom plate 64. When a sealing member is provided between the reinforcing plate 30 and the bottom plate 64 in order to prevent the refrigerant from leaking, the sealing member can be pressed more strongly by the structure of this example.

  FIG. 15 is a diagram showing an outline of a vehicle 200 according to one embodiment of the present invention. The vehicle 200 is a vehicle that generates at least a part of propulsive power using electric power. As an example, the vehicle 200 is an electric vehicle that generates all propulsive power with a power driving device such as a motor, or a hybrid vehicle that uses a power driving device such as a motor and an internal combustion engine that is driven by fuel such as gasoline. .

  The vehicle 200 includes a control device 210 (external device) that controls power driving equipment such as a motor. The control device 210 is provided with the semiconductor module 100. The semiconductor module 100 may control the power supplied to the power driving device.

  FIG. 16 is a main circuit diagram of the semiconductor module 100 according to one embodiment of the present invention. The semiconductor module 100 may be a part of a vehicle-mounted unit that drives a vehicle motor. The semiconductor module 100 may function as a three-phase AC inverter circuit having output terminals U, V, and W.

  The semiconductor chips 78-1, 78-2, and 78-3 may constitute a lower arm in the semiconductor module 100, and the plurality of semiconductor chips 78-4, 78-5, and 78-6 may constitute an upper arm in the semiconductor module 100. The set of semiconductor chips 78-1 and 78-4 may constitute a leg. The set of semiconductor chips 78-2 and 78-5 and the set of semiconductor chips 78-3 and 78-6 may also constitute legs. In the semiconductor chip 78-1, the emitter electrode may be electrically connected to the input terminal N1, and the collector electrode may be electrically connected to the output terminal U. In the semiconductor chip 78-4, the emitter electrode may be electrically connected to the output terminal U, and the collector electrode may be electrically connected to the input terminal P1. Similarly, in the semiconductor chips 78-2 and 78-3, the emitter electrode may be electrically connected to the input terminals N2 and N3, respectively, and the collector electrode may be electrically connected to the output terminals V and W, respectively. Further, in the semiconductor chips 78-5 and 78-6, the emitter electrode may be electrically connected to the output terminals V and W, respectively, and the collector electrode may be electrically connected to the input terminals P2 and P3, respectively.

  Each of the semiconductor chips 78-1 to 78-6 may be alternately switched by a signal input to the control electrode pad of the semiconductor chip 78. In this example, each semiconductor chip 78 may generate heat during switching. The input terminals P1, P2, and P3 may be connected to the positive electrode of the external power supply, the input terminals N1, N2, and N3 may be connected to the negative electrode, and the output terminals U, V, and W may be connected to the load. Input terminals P1, P2, and P3 may be electrically connected to each other, and other input terminals N1, N2, and N3 may also be electrically connected to each other.

  In the semiconductor module 100, each of the plurality of semiconductor chips 78-1 to 78-6 may be an RC-IGBT (Reverse Conducting IGBT) semiconductor chip. In the RC-IGBT semiconductor chip, the IGBT and the free wheeling diode (FWD) may be integrally formed, and the IGBT and the FWD may be connected in antiparallel. The plurality of semiconductor chips 78-1 to 78-6 may each include a combination of a transistor such as a MOSFET or IGBT and a diode. The chip substrate of the transistor and the diode may be a silicon substrate, a silicon carbide substrate, or a gallium nitride substrate.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

DESCRIPTION OF SYMBOLS 10 ... Cooling device, 20 ... Top plate, 22 ... Upper surface, 24 ... Lower surface, 26 ... Short side, 28 ... Long side, 30 ... Reinforcement plate, 32 ... -Base part, 34 ... Projection part, 36 ... Short side, 38 ... Long side, 40 ... Case part, 41 ... Outer edge part, 42 ... Bottom plate opening part, 43 ... -Reinforcing plate opening, 44 ... throttle part, 46 ... short side, 48 ... long side, 49 ... edge, 50 ... edge, 52 ... upper end, 54 ... Lower end, 56 ... brazing material, 62 ... frame part, 63 ... side wall, 64 ... bottom plate, 65 ... upper surface, 66 ... lower surface, 67 ... side surface, 70 ... Semiconductor device 72 ... accommodating portion 74 ... sealing portion 76 ... circuit board 78 ... semiconductor chip 79 ... through hole 81 ... through hole 82 ...・ Through hole, 86 ... Hole, 90 ... pipe, 92 ... refrigerant circulating unit, 94 ... cooling fins 100 ... semiconductor module, 200 ... vehicle, 210 ... control device

Claims (13)

A cooling device for a semiconductor module including a semiconductor chip,
With the top plate,
A refrigerant circulation part, an outer edge part surrounding the refrigerant circulation part, and a bottom plate arranged to face the top plate, wherein the bottom plate has an upper surface facing the top plate and a lower surface opposite to the upper surface. The refrigerant circulation part is disposed between the lower surface of the top plate and the upper surface of the bottom plate, and the case portion is disposed in close contact with the lower surface of the top plate directly or indirectly at the outer edge portion; ,
Cooling fins arranged in the refrigerant circulation part;
A cooling device comprising: a reinforcing plate fixed to a lower surface of the bottom plate. The cooling device according to claim 1, wherein the reinforcing plate covers 90% or more of the lower surface of the bottom plate. The cooling device according to claim 2, wherein the reinforcing plate is larger than the lower surface of the bottom plate in a plane parallel to the lower surface of the bottom plate. The case portion is provided integrally with the bottom plate, and further includes a side wall that defines the coolant circulation portion between the top plate and the bottom plate,
The ratio of the area where the reinforcing plate covers the lower surface of the bottom plate to the total area of the lower surface of the bottom plate is that the reinforcing plate covers the side surface of the side wall with respect to the total area of the side surfaces of the side wall. The cooling device according to any one of claims 1 to 3, wherein the cooling device is larger than a ratio of the area. The bottom plate has a pair of opposed long sides and a set of opposed short sides in a top view,
The side wall connected to the short side of the bottom plate is provided with a throttle part having a curved shape in a top view from the upper end to the lower end of the side wall,
The cooling device according to claim 4, wherein the throttle portion is not provided on the side wall connected to the long side of the bottom plate. The bottom plate is provided with two bottom plate openings for introducing or deriving the refrigerant into the refrigerant circulation portion,
The cooling device according to any one of claims 1 to 5, wherein the reinforcing plate is provided with a reinforcing plate opening having a smaller opening area than the bottom plate opening at a position overlapping with the bottom plate opening. The reinforcing plate is
A base portion fixed to the bottom surface of the bottom plate;
The cooling device according to claim 4, further comprising: a protruding portion that protrudes upward from the base portion and is fixed to the side wall. The reinforcing plate has a pair of opposed long sides and a set of opposed short sides in a top view,
At least one protrusion is provided on each side of the reinforcing plate;
The cooling device according to claim 7, wherein at least one of the long sides is provided with two or more protrusions. The cooling device according to claim 1, wherein a plurality of the reinforcing plates are stacked. The cooling device according to any one of claims 1 to 9, wherein the reinforcing plate is formed of the same material as the case portion. The cooling device according to any one of claims 1 to 10, wherein the reinforcing plate has the same thickness as the bottom plate of the case portion. The cooling device according to any one of claims 1 to 11,
A semiconductor module comprising: a semiconductor device disposed above the top plate.   A vehicle comprising the semiconductor module according to claim 12.

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