Cooler and semiconductor device

Abstract

A cooler is provided in which the degree of cooling is not likely to become uneven when cooling a plurality of cooling objects. To this end, a flow path of a refrigerant inside the cooler includes: an outer peripheral header region, which is provided on the outer peripheral side of a ring shape and extends in the circumferential direction of the ring shape; an inner peripheral header region, which is provided on the inner peripheral side of the ring shape and is separated from the outer peripheral header region by a separation region and extends in the circumferential direction; and a fin region, which is a separation region and is provided with fins.

Description

Technical Field

[0001] The present invention relates to a cooler and a semiconductor device. Background Art

[0002] Currently, the inverters and motors of electric vehicles such as electric vehicles and hybrid vehicles are surrounded by different metal frames, but are being integrated for the purpose of miniaturization and space saving. DC is supplied from the battery to the inverter, which converts the DC into three-phase AC, and the three-phase AC is supplied to the motor. When the inverter converts DC into three-phase AC, heat is generated due to the loss of semiconductor elements. If semiconductor elements are used at high temperatures, the element itself or the bonding material, the surrounding bonding parts, etc. may be damaged, so it is necessary to use them while cooling.

[0003] For example, Patent Document 1 discloses a structure of a cooler for cooling a plurality of semiconductor elements used in an inverter.

[0004] Patent Document 1: Japanese Patent No. 4708951 Summary of the invention

[0005] In the cooler shown in FIG. 24 of Patent Document 1, the coolant flows in the flow path while absorbing the heat generated by the plurality of semiconductor elements. As the coolant flows in the flow path, the temperature rises due to the heat of the semiconductor elements, and the cooling effect gradually decreases. Thus, when the conventional cooler cools a plurality of cooling objects, the degree of cooling tends to become uneven.

[0006] The present invention is proposed to solve such a problem, and its object is to provide a cooler in which the cooling degree is unlikely to become uneven when cooling a plurality of cooling objects, and a semiconductor device using the cooler in which the cooling degree is unlikely to become uneven when cooling a plurality of cooling objects.

[0007] The cooler of the present invention is ring-shaped when viewed from above from the first direction, and a flow path of the refrigerant is arranged inside the cooler, wherein the flow path includes: an outer peripheral side header area, which is arranged on the outer peripheral side of the ring shape and extends along the circumferential direction of the ring shape; an inner peripheral side header area, which is arranged on the inner peripheral side of the ring shape and is separated from the outer peripheral side header area by a separation area and extends along the circumferential direction; and a fin area, which is a separation area and is equipped with fins.

[0008] In addition, the semiconductor device of the present invention comprises the cooler of the present invention; and a plurality of semiconductor modules, wherein the plurality of semiconductor modules are arranged on a module arrangement surface of the cooler extending along a second direction intersecting the first direction and a third direction intersecting the first direction and the second direction.

[0009] Effects of the Invention

[0010] In the cooler of the present invention, the flow path includes: an outer header region, which is arranged on the outer circumference of the ring shape and extends in the circumferential direction of the ring shape; an inner header region, which is arranged on the inner circumference of the ring shape and is separated from the outer header region by a separation region and extends in the circumferential direction; and a fin region, which is a separation region and is provided with fins. Therefore, in the cooler of the present invention, when cooling a plurality of cooling objects, the cooling degree is not likely to become uneven.

[0011] In addition, the semiconductor device of the present invention comprises the cooler of the present invention and a plurality of semiconductor modules, and the plurality of semiconductor modules are arranged on a module arrangement surface of the cooler extending along a second direction intersecting the first direction and a third direction intersecting the first direction and the second direction. Thus, the semiconductor device of the present invention is a semiconductor device using a cooler in which the degree of cooling is not likely to become uneven when cooling a plurality of cooling objects.

[0012] The objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a cross-sectional view of the semiconductor device according to the first embodiment.

[0014] Figure 2 This is a cross-sectional view of the inverter unit according to the first embodiment.

[0015] Figure 3 This is a perspective view of the semiconductor device according to the first embodiment.

[0016] Figure 4 This is a plan view of the cooler according to the first embodiment as viewed from the axial direction of the semiconductor device.

[0017] Figure 5 This is a cross-sectional view of the cooler according to the first embodiment, taken along a cross section perpendicular to the axis of the semiconductor device.

[0018] Figure 6 This is a cross-sectional view of the cooler according to the first embodiment, taken along a cross section perpendicular to the axis of the semiconductor device.

[0019] Figure 7 This is a cross-sectional view of the inverter unit according to the second embodiment.

[0020] Figure 8 This is a cross-sectional view of the cooler according to the third embodiment, taken along a cross section perpendicular to the axis of the semiconductor device. DETAILED DESCRIPTION

[0021] <A. Implementation method 1>

[0022] <A-1. Structure>

[0023] Figure 1 is a cross-sectional view of a semiconductor device 10 as an inverter device according to the first embodiment. Figure 3 It is a perspective view showing the appearance of the semiconductor device 10 .

[0024] The semiconductor device 10 includes a housing 20, a motor unit 30, and an inverter unit 40. The semiconductor device 10 includes the motor unit 30 that operates as a motor, and is a motor-integrated semiconductor device.

[0025] Figure 2 is a cross-sectional view of the inverter unit 40 according to the first embodiment. Figure 1 Magnified view of the area enclosed by the dotted line.

[0026] The frame 20 is made of metal, such as Figure 3 Shown is cylindrical shape.

[0027] The motor unit 30 includes a stator 31 , a rotor 32 , and a shaft 33 .

[0028] The shaft 33 is rotatably supported by the frame 20 via a bearing, and is disposed so as to pass through the cylindrical center axis of the frame 20. A portion of the shaft 33 protrudes from the frame 20 to the outside.

[0029] A rotor 32 having a permanent magnet having one pair of S-pole and N-pole or a plurality of pairs of S-pole and N-pole is fixed to the shaft 33. The rotor 32 and the shaft 33 are integrated and rotatable relative to the housing 20.

[0030] A stator 31 fixed to the frame 20 is arranged outside the rotor 32. The stator 31 has an electromagnet composed of a stator core fixed to the frame 20 and a stator coil wound around the stator core. The number of electromagnets included in the stator 31 is a multiple of 3 such as 3, 6, or 9, which corresponds to the torque and speed required by the motor. The three-phase AC is supplied to the stator 31 through the inverter unit 40. However, the stator 31 may also use a multi-phase AC other than the three-phase AC. In this case, the number of electromagnets included in the stator 31 is not limited to a multiple of 3.

[0031] The inverter unit 40 includes a plurality of semiconductor modules 42, a control substrate 41, and a cooler 50. The plurality of semiconductor modules 42 are respectively an object to be cooled by the cooler 50.

[0032] The inverter unit 40 supplies three-phase AC to the stator 31. The inverter unit 40 converts DC supplied from a battery outside the semiconductor device 10 into AC and supplies the AC to the stator 31. The inverter unit 40 includes a number of semiconductor modules 42 required to generate the AC supplied to the stator 31. In this embodiment, six semiconductor modules 42 are described.

[0033] Figure 4 is a top view of the cooler 50 when viewed from the first direction. Figure 1 The cooler 50 is axially directed to the shaft 33. Figure 4 As shown, it is in a ring shape when viewed from the top as viewed from the first direction. Figure 4 The semiconductor module 42 arranged on the surface of the cooler 50 is also shown. In the present invention, when simply referred to as an annular shape, it means the annular shape when the cooler 50, 150, 250 of each embodiment is viewed from the first direction. In addition, when simply referred to as a circumferential direction or a radial direction, it means the circumferential direction or the radial direction of the annular shape of the cooler 50, 150, 250 of each embodiment when viewed from the first direction.

[0034] A flow path of a refrigerant is provided inside the cooler 50. The refrigerant is, for example, cooling water. Figure 5 and Figure 6 2 is a cross-sectional view of the cooler 50 at a cross section perpendicular to the first direction and passing through the flow path of the refrigerant. Figure 6 In FIG. 1 , the position of the semiconductor module 42 when viewed from above from the first direction is indicated by a dotted line.

[0035] The cooler 50 has an outer circumferential side pipe 54 and an inner circumferential side pipe 55. Figure 5 and Figure 6 5 shows the positions of the outer tube connection region 54a where the outer tube 54 is connected to the frame of the cooler 50 and the inner tube connection region 55a where the inner tube 55 is connected to the frame of the cooler 50 when viewed from above from the first direction. The flow path connecting the inner tube 55 and the outer tube 54 inside the cooler 50 includes the outer header region 51, the inner header region 52, and the fin region 53.

[0036] The outer peripheral side header region 51 is provided on the outer peripheral side of the annular shape and extends in the circumferential direction.

[0037] The inner circumference side header region 52 is provided on the inner circumference side of the ring shape so as to sandwich a separation region from the outer circumference side header region 51 , and extends in the circumferential direction.

[0038] In this embodiment, the separation region is the same region as the fin region 53. The fin region 53 is provided in a region sandwiched in the radial direction by the inner circumference side header region 52 and the outer circumference side header region 51, and extends in the circumferential direction. Figure 5 As shown in FIG. 1 , fins 57 are arranged in the fin region 53. In the fin region 53, refrigerant flows between the outer circumferential side header region 51 and the inner circumferential side header region 52. Figure 1 , Figure 2 and Figure 6 In FIG. 5 , for easy observation, the fin region 53 is shown by a dot pattern.

[0039] The fins 57 are preferably fins having high cooling efficiency, such as pin fins and corrugated fins. Figure 5 The case where the fin 57 is a pin fin is depicted.

[0040] Even if the circumferential angles of the outer manifold area 51 and the inner manifold area 52 are the same, the circumferential length of the outer manifold area 51 is longer than that of the inner manifold area 52. Therefore, it is easier for the outer manifold area 51 to generate a circumferential pressure difference of the refrigerant than the inner manifold area 52. In order to reduce the circumferential pressure difference of the refrigerant in the outer manifold area 51, it is preferred that the radial width W1 of the outer manifold area 51 is larger than the radial width W2 of the inner manifold area 52. Since the circumferential pressure difference of the refrigerant in the outer manifold area 51 is reduced, the cooler 50 is a cooler in which the degree of cooling is less likely to become uneven when cooling a plurality of cooling objects. Figure 5 W1 and W2 are shown in FIG.

[0041] It is preferred that the outer header region 51 and the inner header region 52 have almost no flow resistance to the refrigerant. In particular, it is preferred that the flow resistance to the refrigerant in the outer header region 51 and the inner header region 52 is sufficiently smaller than the flow resistance to the refrigerant in the fin region 53 .

[0042] The semiconductor module 42 includes a semiconductor element 43, a heat sink 46, a main terminal 45, a signal terminal 44, and a sealing resin 47. The semiconductor element 43 is bonded to the heat sink 46 by a brazing material such as solder, and is sealed by the sealing resin 47. The semiconductor module 42 has a surface from which the heat sink 46 is exposed. In addition, one side of each of the main terminal 45 and the signal terminal 44 is connected to the semiconductor element 43, and the opposite side extends to the outside of the sealing resin 47. However, the structure of the semiconductor module 42 is not limited to such an example. For example, the semiconductor module 42 may not have the heat sink 46, and the semiconductor module 42 may be the semiconductor element 43 itself.

[0043] like Figure 4As shown, a plurality of semiconductor modules 42 are arranged on a module arrangement surface 58 of a cooler 50 extending in a second direction intersecting the first direction and in a third direction intersecting the first direction and the second direction. A plurality of semiconductor modules 42 are arranged circumferentially on the module arrangement surface 58, and are cooled uniformly by the cooler 50. In the present embodiment, the first direction is illustrated as being perpendicular to a plane formed by the second direction and the third direction, but the first direction is not necessarily perpendicular to a plane formed by the second direction and the third direction.

[0044] The semiconductor modules 42 are arranged so that the heat sink 46 contacts the module arrangement surface 58 of the cooler 50. The cooling capacity of the portion corresponding to the fin region 53 in the module arrangement surface 58 is higher than that of the other portions, and therefore, the semiconductor modules 42 are arranged on the module arrangement surface 58 of the cooler 50 so that the region of the heat sink 46 overlaps with the fin region 53 when viewed from the first direction. In addition, the overlap includes the case of partial overlap.

[0045] In order to fully generate the cooling capacity obtained by the fin area 53, the semiconductor modules 42 are preferably arranged on the module arrangement surface 58 of the cooler 50 in such a manner that the area of ​​the heat sink 46 is included in the fin area 53 when viewed from the first direction. Considering the diffusion of heat conducted from the heat sink 46 to the cooler 50 at the outer wall of the cooler 50, it is further preferred that the fin area 53 extends outward from the area of ​​the heat sink 46 of each semiconductor module 42 to a distance greater than or equal to the thickness of the outer wall of the cooler 50 when viewed from the first direction.

[0046] In order to fill the small gap between each semiconductor module 42 and the cooler 50 to facilitate heat conduction, for example, grease with filler is filled in. In addition, each semiconductor module 42 is abutted against the cooler 50 by a spring or a screw (not shown).

[0047] Each semiconductor module 42 is connected to the stator coil of the stator 31 via a bus bar or lead wire (not shown) disposed inside the frame 20, and a three-phase alternating current is supplied from the inverter unit 40 to the stator coil of the stator 31. In addition, in order to operate the semiconductor device 10, a bus bar or lead wire for inputting a direct current from a battery, for example, outside the frame 20 to each semiconductor module 42 is necessary, but is not shown in the figure.

[0048] The control substrate 41 is used to detect an input signal, current, or temperature to the semiconductor module 42 through the signal terminal 44 , and protect the semiconductor element 43 .

[0049] When viewed from the axial direction of the shaft 33, the control substrate 41 and the cooler 50 are each in the shape of a ring with a hole in the center, and the outer peripheral portion of each ring shape is mounted and fixed to the frame 20. The control substrate 41 and the cooler 50 are fixed to the frame 20 in a manner that the shaft 33 passes through the respective ring-shaped hole portions of the control substrate 41 and the cooler 50.

[0050] <A-2. Action>

[0051] The inverter unit 40 converts direct current into alternating current by sequentially turning on and off a plurality of semiconductor elements 43, but at this time, Joule heat is generated due to the resistance and current of the semiconductor element 43. The semiconductor element 43 and its peripheral components each have a material-specific heat-resistant temperature, which needs to be maintained at a temperature less than or equal to the heat-resistant temperature. In addition, since the linear expansion coefficients of the materials being joined are different, the amount of expansion and contraction due to temperature changes is also different. At the portion where the materials are joined, deformation occurs due to the difference in the amount of expansion and contraction, resulting in cracks and peeling. Therefore, in order to keep the temperature of the semiconductor module 42 below a certain temperature, it is cooled by the cooler 50. It is preferred that the plurality of semiconductor modules 42 are cooled uniformly.

[0052] The flow direction of the refrigerant depends on the direction in which the pump not shown in the figure, which is not included in the cooler 50, is connected to the outer tube 54 and the inner tube 55. In the present embodiment, the refrigerant is introduced into the cooler 50 from the inner tube 55 and discharged from the outer tube 54 to the outside of the cooler 50. That is, the cooler 50 introduces the refrigerant through the inner tube 55, causes the refrigerant to flow from the inner header region 52 through the fin region 53 to the outer header region 51, and is discharged from the outer tube 54 to the outside of the cooler 50. The refrigerant can also flow in the opposite direction to the above flow direction by connecting the pump to the outer tube 54 and the inner tube 55 in reverse. In addition, the cooler 50 may also include a pump.

[0053] The flow resistance of the inner side header area 52 and the outer side header area 51 is sufficiently small compared to the flow resistance of the fin area 53. Therefore, when the refrigerant flows through the flow path of the cooler 50, the pressure of the refrigerant in the inner side header area 52 and the outer side header area 51 are respectively approximately uniform, and a pressure gradient is generated radially in the fin area 53. For example, the pressure difference between the end of the inner tube connection region 55a side of the inner header region 52 and the end of the outer tube connection region 54a side, and the pressure difference between the end of the inner tube connection region 55a side of the outer header region 51 and the end of the outer tube connection region 54a side are smaller than the pressure difference between the end of the inner tube connection region 55a side of the inner header region 52 and the end of the inner tube connection region 55a side of the outer header region 51, and the pressure difference between the end of the outer tube connection region 54a side of the inner header region 52 and the end of the outer tube connection region 54a side of the outer header region 51. Here, the pressure difference is an absolute value.

[0054] The heat generated by the semiconductor module 42 is conducted to the refrigerant through the outer wall of the cooler 50, or is conducted to the refrigerant through the outer wall of the cooler 50 and the fins 57. Thus, the semiconductor module 42 is cooled.

[0055] Since the pressure of the refrigerant in the inner circumferential side header region 52 and the pressure of the refrigerant in the outer circumferential side header region 51 are respectively substantially uniform, the refrigerant is arranged in the circumferential direction from the inner circumferential side header region 52 toward the outer circumferential side header region 51 and flows through the fin region 53 at a substantially uniform flow rate, and the cooling capacity of the fin region 53 is substantially uniform in the circumferential direction. Therefore, the plurality of semiconductor modules 42 arranged in the circumferential direction on the module arrangement surface 58 are cooled substantially uniformly.

[0056] In this way, the flow path of the cooler 50 includes: an outer peripheral side header area 51, which is arranged on the outer peripheral side of the ring shape and extends in the circumferential direction; an inner peripheral side header area 52, which is arranged on the inner peripheral side of the ring shape and is separated from the outer peripheral side header area 51 by a separation area, and extends in the circumferential direction; and a fin area 53, which is a separation area and is provided with fins 57. Therefore, the cooler 50 is a cooler in which the cooling degree is not easy to become uneven when cooling a plurality of cooling objects.

[0057] In the motor unit 30, a three-phase alternating current is passed to the stator 31, a magnetic field is generated, and the rotor 32 is rotated, and the electric energy is converted into kinetic energy. However, the conversion efficiency is not 100%, and part of the energy becomes loss, and the loss is almost converted into heat. Therefore, the motor unit 30 also needs to be cooled as needed, but in the figure of this embodiment, the cooling of the motor unit 30 is omitted.

[0058] If the motor unit 30 generates heat, the heat is conducted to the inverter unit 40 through the metal frame 20. The cooler 50 is fixed to the frame 20 on the outer peripheral side, so the temperature of the outer peripheral side of the cooler 50 may rise, and the temperature of the refrigerant in the outer peripheral side header area 51 may also rise. However, the refrigerant flows in the order of the inner peripheral side header area 52, the fin area 53, and the outer peripheral side header area 51. Therefore, the refrigerant in the outer peripheral side header area 51 is the refrigerant after cooling the semiconductor module 42, and the influence of the heat generated by the motor unit 30 on the cooling of the semiconductor module 42 by the fin area 53 is suppressed.

[0059] <A-3. Effect>

[0060] The flow path of the cooler 50 includes: an outer circumferential side header region 51, which is provided on the outer circumferential side of the ring shape and extends in the circumferential direction; an inner circumferential side header region 52, which is provided on the inner circumferential side of the ring shape with a separation region between the outer circumferential side header region 51 and extends in the circumferential direction; and a fin region 53, which is a separation region and is provided with fins 57. Thus, the cooler 50 is a cooler in which the degree of cooling is unlikely to become uneven when cooling a plurality of cooling objects.

[0061] In cooler 50, refrigerant flows from inner header region 52 to outer header region 51 through fin region 53. This suppresses the influence of heat conducted to cooler 50 from frame 20 fixing cooler 50 on cooling by fin region 53.

[0062] In the cooler 50, the radial width of the outer header region 51 is preferably larger than the radial width of the inner header region 52. Thus, the cooler 50 is a cooler in which the degree of cooling is less likely to become uneven when cooling a plurality of cooling objects.

[0063] In the semiconductor device 10 , the plurality of semiconductor modules 42 are arranged on the module arrangement surface 58 of the cooler 50 . Thus, the plurality of semiconductor modules 42 can be cooled by the cooler 50 .

[0064] In the semiconductor device 10, the plurality of semiconductor modules 42 are arranged side by side in the circumferential direction on the module arrangement surface 58 of the cooler 50. Thus, the plurality of semiconductor modules 42 can be cooled uniformly by the cooler 50.

[0065] In semiconductor device 10 , semiconductor modules 42 are arranged on module arrangement surface 58 of cooler 50 such that the heat sink 46 overlaps fin region 53 when viewed from the first direction. Thus, semiconductor modules 42 can be cooled by fin region 53 .

[0066] In the semiconductor device 10, the plurality of semiconductor modules 42 are preferably arranged on the module arrangement surface 58 of the cooler 50 such that the region of the heat sink 46 is included in the fin region 53 when viewed from the first direction. Thus, the plurality of semiconductor modules 42 can be efficiently cooled by the fin region 53.

[0067] In the semiconductor device 10, when viewed from the first direction, the fin region 53 preferably includes a distance extending outward from the region of the heat sink 46 of each of the plurality of semiconductor modules 42 to a distance greater than or equal to the thickness of the outer wall of the cooler 50. Thus, the plurality of semiconductor modules 42 can be cooled more efficiently by the fin region 53.

[0068] The semiconductor device 10 is a motor-integrated semiconductor device. Thus, a motor-integrated semiconductor device capable of cooling the plurality of semiconductor modules 42 by the cooler 50 is realized.

[0069] <B. Implementation method 2>

[0070] <B-1. Structure and operation>

[0071] The semiconductor device of the present embodiment (hereinafter referred to as semiconductor device 110 ) is different from the semiconductor device 10 in that it includes an inverter unit 140 instead of the inverter unit 40 . The semiconductor device 110 is the same as the semiconductor device 10 in other respects.

[0072] Figure 7 is a diagram showing a half of the cross section of the inverter unit 140, which is similar to the inverter unit 40 of the first embodiment. Figure 2 The corresponding figure.

[0073] The inverter unit 140 is different from the inverter unit 40 in that it includes a cooler 150 instead of the cooler 50. In the inverter unit 140, the main terminal 45 of the semiconductor module 42 is cooled by the cooler 150. The inverter unit 140 is the same as the inverter unit 40 in other respects.

[0074] The refrigerant flow path inside the cooler 150 includes: an outer circumferential side header region 51, which is provided on the outer circumferential side of the ring shape and extends in the circumferential direction of the ring shape; an inner circumferential side header region 152, which is provided on the inner circumferential side of the ring shape with a separation region sandwiched between the outer circumferential side header region 51 and extends in the circumferential direction; and a fin region 53, which is a separation region and is provided with fins 57. The outer circumferential side header region 51 and the fin region 53 are the same regions as those of the cooler 50 of the first embodiment.

[0075] The width of the inner circumferential side header region 152 in the first direction is greater than the width of the fin region 53 in the first direction. As a result, the cross-sectional area of ​​the flow path of the inner circumferential side header region 152 can be increased, so that the flow path resistance of the inner circumferential side header region 152 can be reduced and the internal pressure of the inner circumferential side header region 152 can be uniformed, and the cooling capacity achieved by the fin region 53 becomes more uniform in the circumferential direction. Figure 7 , the fin region 53 is shown by a dot pattern in an easily observable manner.

[0076] The portion of the module arrangement surface 158 of the cooler 150 extending in the second direction intersecting the first direction and in the third direction intersecting the first direction and the second direction corresponding to the inner circumferential side header region 152 protrudes more than the portion corresponding to the fin region 53. Thus, it is easy to realize a structure in which the width of the inner circumferential side header region 152 in the first direction is larger than the width of the fin region 53 in the first direction.

[0077] In the inverter unit 140, the main terminal 45 of each semiconductor module 42 is in contact with the protruding portion of the module configuration surface 158 via the insulating material 60. The insulating material 60 is, for example, a glass coating. Due to the heat generated by the large current flowing for driving the motor unit 30 and the heat being conducted from the semiconductor element 43 by bonding with the semiconductor element 43, the main terminal 45 sometimes becomes high temperature. The main terminal 45 is cooled by contacting the protruding portion of the module configuration surface 158 via the insulating material 60. The heat generated by the main terminal 45 is smaller than the heat generated by the semiconductor element 43, so that it is sufficient to rely on the cooling achieved by the portion corresponding to the inner circumferential side header region 152 without relying on the fin region 53. The main terminal 45 is in contact with the portion of the module configuration surface 158 of the cooler 150 that protrudes compared to the portion corresponding to the fin region 53, thereby facilitating the wiring for cooling the main terminal 45 through the cooler 150.

[0078] In the above description, the case where the width of the inner circumferential side header region 152 in the first direction is greater than the width of the fin region 53 in the first direction is described, but the width of at least one region in the outer circumferential side header region 51 and the inner circumferential side header region 152 in the first direction may be greater than the width of the fin region 53 in the first direction. Thus, the cross-sectional area of ​​the flow path of the at least one region can be increased, so that the flow path resistance of the at least one region can be reduced and the internal pressure of the at least one region can be uniformized, and the cooling capacity achieved by the fin region 53 becomes more uniform in the circumferential direction. That is, the cooler 150 becomes a cooler in which the degree of cooling is less likely to become uneven when cooling a plurality of cooling objects.

[0079] Furthermore, if the portion corresponding to the one region in the module arrangement surface 158 of the cooler 150 is made to protrude more than the portion corresponding to the fin region 53, it is possible to easily realize a structure in which the width of the at least one region in the first direction is larger than the width of the fin region 53 in the first direction. The main terminals 45 of each of the plurality of semiconductor modules 42 are arranged so as to contact the protruding portion corresponding to the at least one region via the insulating material 60, so that the main terminals 45 can be cooled.

[0080] <B-2. Effect>

[0081] The cooler 150 may be configured such that the width in the first direction of at least one of the outer header region 51 and the inner header region 152 is greater than the width in the first direction of the fin region 53. With this configuration, the cooler 150 is less likely to have uneven cooling when cooling a plurality of cooling objects.

[0082] The module arrangement surface 158 of the cooler 150 may also be configured such that a portion corresponding to at least one region protrudes compared to a portion corresponding to the fin region 53. According to this configuration, it is possible to easily realize a structure of the cooler 150 in which the width in the first direction of at least one region of the outer circumferential side header region 51 and the inner circumferential side header region 152 is larger than the width in the first direction of the fin region 53.

[0083] In the semiconductor device 110, the main terminals 45 of each of the plurality of semiconductor modules 42 are in contact with the protruding portion of the module arrangement surface 158 via the insulating material 60. This makes it possible to cool the main terminals 45. The main terminals 45 are in contact with the portion of the module arrangement surface 158 of the cooler 150 that protrudes from the portion corresponding to the fin region 53, so that wiring for cooling the main terminals 45 through the cooler 150 becomes easy.

[0084] <C. Implementation method 3>

[0085] <C-1. Structure and operation>

[0086] like Figure 5 and Figure 6 As shown, in the cooler 50 of the first embodiment, the fin region 53 extends in the circumferential direction, and the plurality of semiconductor modules 42 are arranged at intervals in the region corresponding to the fin region 53 of the module arrangement surface 58. In the structure of the first embodiment, the semiconductor modules 42 can be cooled by the fin region 53, but the refrigerant also flows through the portion of the fin region 53 corresponding to the interval between the semiconductor modules 42. Even if the refrigerant flows through the portion of the fin region 53 corresponding to the portion where the semiconductor module 42 is not arranged, the contribution to the cooling of the semiconductor module 42 is small.

[0087] The inverter unit (hereinafter referred to as inverter unit 240) of the semiconductor device of this embodiment (hereinafter referred to as semiconductor device 210) has a cooler 250 instead of the cooler 50, compared with the inverter unit 40 of the semiconductor device 10 of the first embodiment. In other respects, the inverter unit 240 is the same as the inverter unit 40. In addition, the semiconductor device 210 is the same as the semiconductor device 10 except that the inverter unit 240 is replaced by the inverter unit 40. The cross-sectional view of the semiconductor device 210 is the same as that of the first embodiment. Figure 1 In addition, the inverter unit 240 is composed of Figure 1 The enlarged image of the area surrounded by the dotted line is Figure 2 However, Figure 1 and Figure 2 In the drawings, regarding components having different reference numerals between the present embodiment and the first embodiment, the reference numerals of the present embodiment are shown in parentheses.

[0088] Figure 8 2 is a cross-sectional view of the cooler 250 at a cross section perpendicular to the first direction and passing through the flow path of the refrigerant. Figure 8 In FIG. 1 , the position of the semiconductor module 42 when viewed from above from the first direction is indicated by a dotted line.

[0089] like Figure 1 and Figure 8 As shown, the flow path inside the cooler 250, like the flow path inside the cooler 50, includes: an outer peripheral side header area 51, which is arranged on the outer peripheral side of the ring shape and extends circumferentially; and an inner peripheral side header area 52, which is arranged on the inner peripheral side of the ring shape and is separated from the outer peripheral side header area 51 by a separation area, and extends circumferentially.

[0090] In the cooler 250, the fin region 253, which is an area where fins are arranged, is provided in the separation area, that is, the area sandwiched in the radial direction by the inner side header area 52 and the outer side header area 51, so that the refrigerant flows between the inner side header area 52 and the outer side header area 51. In addition, the fin region 253 is provided intermittently in the circumferential direction. Thus, by arranging the semiconductor module 42 in the area corresponding to the fin region 253 on the module arrangement surface 58, the semiconductor module 42 can be efficiently cooled. In this embodiment, the separation area is Figure 8 The area shown is a combination of the fin area 253 and the area occupied by the metal block 56 described later. Figure 8 In the figure, the fin region 253 is shown by a dot pattern for easy viewing. The fins arranged in the fin region 253 are, for example, pin fins or corrugated fins, similar to the fins 57 arranged in the fin region 53 in the first embodiment, but are not shown in the figure.

[0091] like Figure 8 As shown, in the semiconductor device 210, the plurality of semiconductor modules 42 are arranged so that the semiconductor modules 42 overlap one by one with the fin regions 253 intermittently provided along the circumferential direction when viewed from above from the first direction. Thus, the refrigerant does not flow through the low efficiency region for cooling each of the plurality of semiconductor modules 42 in the separation region, and each semiconductor module 42 can be efficiently cooled.

[0092] In addition, if Figure 8 As shown, each semiconductor module 42 is arranged on the module arrangement surface 58 of the cooler 250 in such a manner that the area of ​​the heat sink 46 overlaps with the fin area 253 when viewed from above from the first direction. Preferably, each semiconductor module 42 is arranged on the module arrangement surface 58 of the cooler 250 in such a manner that the area of ​​the heat sink 46 is included in the fin area 253 when viewed from above from the first direction. Preferably, when viewed from above from the first direction, the fin area 253 extends outward from the area of ​​the heat sink 46 of each semiconductor module 42 to a distance greater than or equal to the thickness of the outer wall of the cooler 250.

[0093] The cooler 250 further includes a metal block 56, which is disposed in an area of ​​the separation area where the fin area 253 is not provided. The metal blocks 56 are respectively disposed in the portions between the intermittently provided fin areas 253. When the heat generation of the semiconductor module 42 temporarily increases, such as when the motor unit 30 is locked or when a high load is suddenly applied to the semiconductor module 42 due to rapid acceleration of an electric vehicle using the semiconductor device 10, the temperature rise can be suppressed by cooling by the fins 57 and buffering by the heat capacity of the metal block 56. As a result, the output of the pump (not shown) that allows the refrigerant to flow through the cooler 250 can be reduced.

[0094] Aluminum is often used as the material of the cooler, but since the effect is greater as the heat capacity of the metal block 56 increases, copper, which has a large heat capacity per unit volume, is preferably used as the material. However, in this case, in order to prevent corrosion, copper needs to be subjected to surface treatment such as plating. Copper is also suitable as a heat buffer for the sudden increase in heat generation of the semiconductor module 42 because copper has a higher thermal conductivity than aluminum.

[0095] The arrangement of the metal blocks 56 and the fins 57 in the cooler 250 can be changed according to the assumed arrangement of the semiconductor modules 42 on the cooler 250 .

[0096] <C-2. Effect>

[0097] In the cooler 250 , the fin regions 253 are provided intermittently in the circumferential direction, thereby enabling the semiconductor module 42 to be cooled efficiently.

[0098] The cooler 250 further includes a metal block 56, and the metal block 56 is disposed in a region of the separation region where the fin region 253 is not provided. Thus, when the heat generation amount of the semiconductor module 42 temporarily increases, the temperature rise can be suppressed.

[0099] In the semiconductor device 210 , the plurality of semiconductor modules 42 are arranged so that the semiconductor modules 42 overlap one another with the fin regions 253 provided intermittently in the circumferential direction when viewed from above from the first direction. Thus, each semiconductor module 42 can be efficiently cooled.

[0100] <D. Implementation method 4>

[0101] In the first to third embodiments, there is no limitation on the type of semiconductor used in the semiconductor element 43 built into the semiconductor module 42. In this embodiment, the cooler does not use the cooler of the first to third embodiments, and the semiconductor element 43 includes a wide bandgap semiconductor. A wide bandgap semiconductor is a semiconductor having a larger bandgap than silicon, such as a silicon carbide semiconductor. By including a wide bandgap semiconductor, the loss during normal operation is reduced and the heat-resistant temperature is increased.

[0102] In addition, since the loss during normal operation becomes smaller and the heat resistance temperature becomes higher, when the cooler 250 of embodiment 3 is used as a cooler, the amount of heat that the metal block 56 can absorb when the temperature rises from the temperature during normal operation to the heat resistance temperature is greater than the case where the semiconductor element 43 does not include a wide bandgap semiconductor, and the role of the metal block 56 as a thermal buffer is further enhanced.

[0103] While the present invention has been described in detail, the above description is in all aspects illustrative and the present invention is not limited thereto, and it is understood that numerous modifications not shown are conceivable.

[0104] Description of the label

[0105] 10, 110, 210 semiconductor device, 20 frame, 30 motor part, 31 stator, 32 rotor, 33 shaft, 40, 140, 240 inverter part, 41 control substrate, 42 semiconductor module, 43 semiconductor element, 44 signal terminal, 45 main terminal, 46 heat sink, 47 packaging resin, 50, 150, 250 cooler, 51 outer peripheral side header area, 52, 152 inner peripheral side header area, 53, 253 fin area, 54 outer peripheral side tube, 54a outer peripheral side tube connection area, 55 inner peripheral side tube, 55a inner peripheral side tube connection area, 56 metal block, 57 fin, 58, 158 module configuration surface, 60 insulating material.

Claims

1. A cooler having a ring shape when viewed from a first direction, wherein a flow path of a refrigerant is provided inside the cooler, in, The flow path comprises: an outer peripheral side header region, which is provided on the outer peripheral side of the annular shape and extends along the circumferential direction of the annular shape; an inner circumference side header region, which is provided on the inner circumference side of the annular shape with a separation region interposed therebetween from the outer circumference side header region and extends in the circumferential direction; as well as The fin region, which is the separation region, is provided with fins, When the refrigerant flows through the flow path of the cooler, the pressure of the refrigerant in the inner header region and the outer header region is respectively uniform, and a pressure gradient is generated in the radial direction of the fin region so that the flow path resistance of the outer header region and the inner header region to the refrigerant is smaller than the flow path resistance of the fin region to the refrigerant. In the fin region, the flow paths are formed to be aligned along the circumferential direction.

2. The cooler according to claim 1, wherein: The refrigerant is caused to flow from the inner header region through the fin region toward the outer header region.

3. The cooler according to claim 1 or 2, wherein: A radial width of the annular shape of the outer circumference side header region is greater than a radial width of the inner circumference side header region.

4. The cooler according to claim 1 or 2, wherein: A width of at least one of the outer circumferential-side header region and the inner circumferential-side header region in the first direction is larger than a width of the fin region in the first direction.

5. The cooler according to claim 4, wherein: A surface of the cooler extending in a second direction intersecting the first direction and a third direction intersecting the first direction and the second direction is configured such that a portion corresponding to the at least one region protrudes more than a portion corresponding to the fin region.

6. The cooler according to claim 1 or 2, wherein: The fin regions are disposed intermittently along the circumferential direction.

7. The cooler according to claim 6, wherein: Also has a metal block, The metal block is disposed in a region of the separation region where the fin region is not provided.

8. A semiconductor device comprising: The cooler according to any one of claims 1 to 7; and Multiple semiconductor modules, The plurality of semiconductor modules are arranged on a module arrangement surface of the cooler extending along a second direction intersecting the first direction and a third direction intersecting the first direction and the second direction.

9. The semiconductor device according to claim 8, wherein: The plurality of semiconductor modules are arranged on the module arrangement surface of the cooler so as to be aligned along the circumferential direction.

10. The semiconductor device according to claim 8 or 9, wherein: Each of the plurality of semiconductor modules has a heat sink, Each of the plurality of semiconductor modules is arranged on the module arrangement surface of the cooler so that a region of the heat sink overlaps with a region of the fin when viewed in a plan view from the first direction.

11. The semiconductor device according to claim 10, wherein Each of the plurality of semiconductor modules is arranged on the module arrangement surface of the cooler such that a region of the heat sink is included in the fin region when viewed in a plan view from the first direction.

12. The semiconductor device according to claim 11, wherein When viewed in a plan view from the first direction, the fin region extends outward from the region of the heat sink of each of the plurality of semiconductor modules to a distance greater than or equal to the thickness of the outer wall of the cooler.

13. The semiconductor device according to claim 8 or 9, wherein: The cooler is the cooler according to claim 5, The plurality of semiconductor modules each have a main terminal, The main terminal of each of the plurality of semiconductor modules contacts the protruding portion of the surface of the cooler extending in a second direction intersecting the first direction and a third direction intersecting the first direction and the second direction via an insulating material.

14. The semiconductor device according to claim 8 or 9, wherein: The cooler is the cooler according to claim 6 or 7, The plurality of semiconductor modules are arranged so that the semiconductor modules overlap one by one with the fin regions provided intermittently along the circumferential direction when viewed in a plan view from the first direction.

15. The semiconductor device according to claim 8 or 9, wherein: The plurality of semiconductor modules include wide bandgap semiconductors.

16. The semiconductor device according to claim 15, wherein: The wide bandgap semiconductor is a silicon carbide semiconductor.

17. The semiconductor device according to claim 8 or 9, wherein: The semiconductor device is a motor-integrated semiconductor device. It also has a frame and a motor part. The motor unit includes a shaft rotatably supported by the frame, a rotor fixed to the shaft, and a stator fixed to the frame. The cooler is fixed to the frame in such a manner that the shaft passes through the annular hole portion.

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