Semiconductor device

Abstract

Semiconductor device comprising: a cooling jacket (4) which has a passage through which a coolant flows within the cooling jacket (4); a first power module (31) which is mounted on a first surface part (41) of the cooling jacket (4); a second power module (32) mounted on a second surface part (42) of the cooling jacket (4), the second surface part (42) being opposite the first surface part (41); and a third power module (33) mounted on a third surface part (400) of the cooling jacket (4), wherein the third surface part (400) connects an end of the first surface part (41) and an end of the second surface part (42), wherein the cooling jacket (4) has: a first lamella (21) in contact with the first surface part (41) in the passage; a second lamella (22) in contact with the second surface part (42) in the passage; a third lamella (23) in contact with the third surface part (400) in the passage; an inlet opening (1A) through which the coolant is admitted from the outside; an inlet distributor (7A) designed to direct the coolant entering from the inlet opening (1A) to the first fin (21) and the second fin (22); an outlet opening (1B) through which the coolant is discharged to the outside; an outlet manifold (7B) designed to direct the coolant flowing through the first fin (21) and the second fin (22) to the outlet opening (1B), and wherein the first power module (31) and the second power module (32) are opposite each other by the first surface part (41) and the second surface part (42) and by the first lamella (21) and the second lamella (22).

Description

Background of the inventionField of the invention

[0001] The present invention relates to a semiconductor device having a plurality of power modules and a cooling mechanism for the power modules. Description of the state of the art

[0002] An example of cooling structures for power modules includes a direct cooling structure in which a base plate with the power modules has fins on a bottom surface of the base plate. In the direct cooling structure, the base plate is connected to a side surface portion of a cooling jacket through a sealing structure to form a top surface portion of the cooling jacket, and the fins are enclosed within the cooling jacket (e.g., JP 2015 - 53 318 A).

[0003] In JP 2015-53318 A, a semiconductor device has a cooling structure on only one side of a power module. Therefore, in a semiconductor device requiring multiple power modules, where the semiconductor device is intended for use in motor vehicles or other products, semiconductor devices are provided for each power module, or power modules are arranged on a flat surface. Unfortunately, this prevents the semiconductor device from having a small footprint.

[0004] From DE 10 2013 224 970 A1, a liquid coolant supply manifold is known which is configured at a central portion in the width direction between an upper-portion heat sink and a partition plate, wherein a liquid coolant discharge manifold is configured at a central portion in the width direction between a lower-portion heat sink and the partition plate to be parallel to the liquid coolant supply manifold, wherein vertical flow channels are formed to pass vertically through the partition plate on two sides in the width direction to be parallel to the liquid coolant supply manifold, wherein a liquid coolant distribution structural body is arranged inside the liquid coolant supply manifold, and wherein an outer shape of the liquid coolant distribution structural body is configured such thatthat a flow channel cross-sectional area of ​​the liquid coolant supply manifold gradually becomes smaller from an upstream end to a downstream end.,

[0005] Further documents: JP 2004- 332 977 A JP 2007- 250 701 A US 2014 / 0 168 897 A1 US 2015 / 0 097 281 A1 Summary of the invention

[0006] It is an object of the present invention to provide a semiconductor device having a small footprint, the semiconductor device comprising a plurality of power modules and a cooling structure for the power modules.

[0007] This problem is solved by the features of the independent claim. The subclaims contain advantageous embodiments of the invention.

[0008] These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. Short description of the drawings Fig. 1 is a cross-sectional view of a semiconductor device according to a first example for explaining the invention; Fig. 2 is a plan view of the semiconductor device according to the first example; Fig. 3 is a plan view of a semiconductor device according to a comparative example of the present invention; Fig. 4 is a cross-sectional view of a semiconductor device according to a second example; Fig. 5 is a plan view of the semiconductor device according to the second example; Fig. 6 is a cross-sectional view of a semiconductor device according to a first preferred embodiment of the present invention; Fig. 7A and Fig. 7B are structural diagrams of a semiconductor device according to a third example; Fig. Fig. 8 is a plan view of the semiconductor device according to the third example; and Fig. 9 is a plan view of a semiconductor device according to a variation of the third example. Description of the examples and embodiments<A. Erstes Beispiel>

[0009] Fig. 1 is a cross-sectional view of an arrangement of a semiconductor device 101 according to a first example. Fig. 2 is a plan view of the semiconductor device 101. Fig. 1 is a cross-sectional view taken along a line AA in Fig. 2.

[0010] The semiconductor device 101 has a direct cooling structure. The semiconductor device 101 includes two power modules 31 and 32, fins 21 and 22 for radiating heat from the power modules 31 and 32, and a cooling jacket 4 that cools the fins 21 and 22.

[0011] The power module 31 is mounted on a base plate. The fin 21, which is used to radiate the heat of the power module 31, is fixed to a rear surface of the base plate. Further, the base plate, which has the power module 31, is in close contact with a side surface part 40 (third surface part) of the cooling jacket 4 through a seal 51. The base plate thus forms a top plate 41, which is a top surface part (first surface part) of the cooling jacket 4. The top plate 41 and the side surface part 40 are fixed at their respective four corners with fixing bolts 61.

[0012] Further, the power module 32 is mounted on the base plate. The fin 22, which is used to radiate the heat of the power module 32, is fixed to the back surface of the base plate. Further, the base plate, which has the power module 32, is in close contact with the side surface part 40 of the cooling jacket 4 through a seal 52. The base plate thus forms a top plate 42, which is a bottom surface part (second surface part) of the cooling jacket 4. The top plates 41 and 42 face each other. Therefore, the power modules 31 and 32 are provided to face each other through the top plates 41 and 42 and the fins 21 and 22. The top plate 42 and the side surface part 40 are fixed at their respective four corners with fastening bolts 62.

[0013] Examples of the seals 51 and 52 include an O-ring, a liquid gasket, and an ultraviolet-cured rubber seal. The top plates 41 and 42 are brought into close contact with the side surface portion 40 as described above, so that the fins 21 and 22 are enclosed within the cooling jacket 4. Note that the fins 21 and 22 may be connected to the side surface portion 40 by direct brazing or direct welding.

[0014] Furthermore, as in Fig. 2, the cooling jacket 4 has an inlet port 1A and an outlet port 1B for a coolant. Disposed within the cooling jacket 4 are an inlet manifold 7A, which is a space for guiding the coolant entering from the inlet port 1A to the fins 21 and 22, and an outlet manifold 7B, which is a space for guiding the coolant flowing through the fins 21 and 22 to the outlet port 1B. Further, there is a partition plate 81 between all the fins 21 and 22. A coolant having a low temperature flowing through the inlet manifold 7A is divided by the partition plate 81 into two coolant parts: one flows through the fin 21; and the other flows through the fin 22. These two divided coolant parts then flow through the respective fins 21 and 22 and are thus subjected to heat exchange.A high-temperature coolant resulting from flowing through the fins 21 and 22 is discharged from the outlet port 1B through the outlet manifold 7B.

[0015] Now a reference is made to a comparative example. Fig. 3 is a plan view of a conventional semiconductor device 100. The conventional semiconductor device 100 is configured such that the cooling jacket 4 has two power modules 31 and 32 on the top plate 41 (top surface portion) of the cooling jacket 4. Therefore, the semiconductor device 100 required a footprint (bottom surface) sufficient for the two power modules.

[0016] In contrast, according to the first example, the semiconductor device 101 is configured such that the power module 31 is disposed on the top plate 41, which is the upper surface part of the cooling jacket 4, and the second power module 32 is disposed on the top plate 42, which is the lower surface part of the cooling jacket 4, so that the power modules 31 and 32 are opposed to each other. In other words, the semiconductor device 101 includes the cooling jacket 4, which has a passage inside through which the coolant flows, the power module 31 (first power module) mounted on the top plate 41 (first surface part) of the cooling jacket 4, and the power module 32 (second power module) mounted on the second surface part of the cooling jacket 4, which is opposed to the first surface part.The cooling jacket 4 includes: the fin 21 (first fin) in contact with the top plate 41 in the passage; the fin 22 (second fin) in contact with the top plate 42 in the passage; the inlet port 1A through which the coolant is admitted from the outside; the inlet manifold 7A that guides the coolant entering from the inlet port 1A to the fins 21 and 22; the outlet port 1B through which the coolant is discharged to the outside; and the outlet manifold 7B that guides the coolant flowing through the fins 21 and 22 to the outlet port 1B. The power modules 31 and 32 are opposed to each other through the top plates 41 and 42 and through the fins 21 and 22. Therefore, the semiconductor device 101 has a greatly reduced footprint compared to the semiconductor device 100.

[0017] Furthermore, the cooling jacket 4 has a separation plate 81 that separates the fins 21 and 22 in the passage. This allows the coolant to flow through both fins 21 and 22.

[0018] Fig. 1 illustrates the semiconductor device provided with two power modules. The present invention is also suitable for a semiconductor device provided with more than two power modules. For example, a semiconductor device provided with four power modules may be configured such that one group of two power modules is mounted on the top plate 41 and another group of two power modules is mounted on the top plate 42, such that these groups of two modules face each other. Such an arrangement enables a reduction in the footprint of the semiconductor device. <B. Zweites Beispiel>

[0019] Fig. 4 is a cross-sectional view of an arrangement of a semiconductor device 102 according to a second example. Fig. 5 is a plan view of the semiconductor device 102. Fig. 4 is a cross-sectional view taken along a line AA in Fig. 5. In the first example, the partition plate 81 is arranged over all the fins 21 and 22. The inlet manifold 7A and the outlet manifold 7B are thus arranged outside the fins 21 and 22. Therefore, the sizes of the top plates 41 and 42 are determined by the sizes of the fins 21 and 22 and by the sizes of the inlet manifold 7A and the outlet manifold 7B.

[0020] In contrast, the semiconductor device 102 has a partition plate 82 arranged only in the middle of the fins 21 and 22, not at end portions of the fins 21 and 22 (left and right ends in Fig. 4). Consequently, ends of a region between the fins 21 and 22 where the partition plate 82 is not present may be an inlet manifold 7A and an outlet manifold 7B.

[0021] Furthermore, as in Fig. 4, the separation plate 82 may have a greater width at its ends close to the fins 21 and 22 than that of the rest of the separation plate 82. In other words, the separation plate 82 may have recesses serving as the inlet manifold 7A and the outlet header 7B.

[0022] According to the second example, the semiconductor device 102 is configured such that the inlet manifold 7A and the outlet manifold 7B are disposed between the fins 21 and 22. Such an arrangement allows the semiconductor device 102 to have the top plates 41 and 42 with sizes as small as the footprints of the inlet manifold 7A and the outlet manifold 7B, compared to the semiconductor device 101 in which the inlet manifold 7A and the outlet manifold 7B are disposed outside the fins 21 and 22. Consequently, the semiconductor device 102 has a small footprint. <C. Erste bevorzugte Ausführungsform>

[0023] Fig. 6 is a cross-sectional view illustrating a configuration of a semiconductor device 103 according to a first preferred embodiment of the present invention. The semiconductor device 103 includes a power module 33 in a direction in which a side surface of a cooling jacket 4 is arranged.

[0024] Specifically, a side surface part 400 of the cooling jacket 4, which includes the power module 33, has a side surface part 401 in close contact with top plates 41 and 42 through seals 51 and 52, respectively, and a side surface part 402 (base plate) in close contact with the side surface part 401 through a seal 53. In other words, the side surface parts 401 and 402 connect ends of the top plates 41 and 42 that are opposite to each other.

[0025] The side surface part 402 has one surface containing the power module 33 and the other surface on which a fin 23 is connected. The other surface of the side surface part 402, on which the fin 23 is connected, has close contact with the side surface part 401 through the seal 53. Therefore, the fin 23 is enclosed within the cooling jacket 4. Further, the side surface part 402 and the side surface part 401 are fastened with fastening bolts 63.

[0026] In other words, the semiconductor device 103 according to the first preferred embodiment includes the power module 33 (third power module) mounted on the side surface part 400 (third surface part) of the cooling jacket 4, the side surface part 400 connecting the ends of the top plate 41 (first surface part) and the top plate 42 (second surface part) of the cooling jacket 4. The cooling jacket 4 includes the fin 23 (third fin) in contact with the side surface part 400 in a passage. In this way, mounting the respective power modules on three surfaces of the cooling jacket 4 enables the semiconductor device to have a small footprint, the semiconductor device including the three power modules and one cooling structure.

[0027] It continues, as in Fig. 6, a partition plate 83 partially extends from the fins 21 and 22 toward the fin 23. Therefore, a coolant flowing through the fins 21 and 22 flows through the fin 23 and then flows into an outlet manifold 7B. In other words, the outlet manifold 7B guides the coolant flowing through the fins 21 and 22 followed by the fin 23 to an outlet port 1B. Consequently, all the fins 21, 22, and 23 are cooled.

[0028] The configuration of semiconductor device 103 is essentially the same as that of semiconductor device 102 according to the second example except for the above-described configuration. Semiconductor device 103 is also the same as semiconductor device 102 except for a side surface portion 40 of cooling jacket 4, which does not include power module 33.

[0029] It should be noted that the coolant can flow in the opposite direction to the direction described above, so that the coolant flowing through the fin 23 can flow through the fins 21 and 22. <D. Drittes Beispiel>

[0030] Fig. 7A and Fig. 7B are cross-sectional views illustrating an arrangement of a semiconductor device 104 according to a third example. Fig. 8 is a plan view of the semiconductor device 104. Fig. 7A illustrates a cooling jacket 4 having a side surface portion 40 and top plates 41 and 42 which are not yet brought into close contact with each other. Fig. Fig. 7B shows a complete version of the semiconductor device 104 after the side surface part 40 and the top plates 41 and 42 are brought into close contact with each other. Fig. 7A is a cross-sectional view taken along a line AA in Fig. 8.

[0031] With respect to the semiconductor device 101 according to the first example, the semiconductor device 104 is configured such that a partition plate 81 is omitted, and fins 21 and 22 are alternately arranged along a passage of a cooling jacket 4. Since the fins 21 and 22 are alternately arranged, the coolant flows through both fins 21 and 22 without the partition plate 81. Furthermore, the fins 21 and 22 do not interfere with each other. This allows the semiconductor device 104 to have a small thickness.

[0032] Furthermore, the semiconductor device 104 is configured such that the fin 22 is fitted into a hole 91 provided on the top plate 41, and the fin 21 is fitted into a hole 92 provided on the top plate 42. Therefore, the fins 21 and 22 are shared by the power modules 31 and 32. Furthermore, the fin 22 may be caulked or brazed within the hole 91, and the fin 21 may be caulked or brazed within the hole 92. This allows the fins to have increased heat dissipation capability.

[0033] In addition, as in Fig. 9, a semiconductor device 104B may be configured such that the fin 21 is so long that it is not in contact with the top plate 42, and that the fin 22 is so long that it is not in contact with the top plate 41.

[0034] Furthermore, in the arrangements according to the above examples and embodiments, the power modules 31, 32, and 33 each include a semiconductor element comprising a wide-bandgap power semiconductor element. A power module comprising a wide-bandgap semiconductor made of a material such as silicon carbide can operate at a high temperature. Therefore, the use of the present invention provides a small-sized semiconductor device with high heat dissipation capability.

[0035] In summary, a semiconductor device according to one aspect of the invention is provided, which has a small footprint, the semiconductor device comprising a plurality of power modules and a cooling structure for these power modules. The semiconductor device comprises: a power module 31 on a top plate 41 of a cooling jacket; and a power module 32 on a top plate 42 of the cooling jacket, the top plate 42 opposing the top plate 41. The cooling jacket has a first fin 21 in contact with the top plate 41 in a passage and a second fin 22 in contact with the top plate 42 in the passage. The power modules 31 and 32 oppose each other through the top plates 41 and 42 and through the fins 21 and 22. List of reference symbols 1A Inlet opening 1B Outlet opening 4 Cooling jacket 7A Inlet manifold 7B Outlet manifold 21, 22, 23 slat 31, 32, 33 Power module 40 side surface part 41 Top plate, first surface part 42 Top plate, second surface part 51, 52, 53 Sealing 61, 62, 63 fixing bolts 81, 82, 83 Separation plate 91, 92 bore 100, 101, 102, 103, 104, 104B semiconductor device 400 third surface part 401 Page Surface Part 402 Side surface part, base plate

Claims

[1] A semiconductor device comprising: a cooling jacket (4) having a passage through which a coolant flows within the cooling jacket (4); a first power module (31) mounted on a first surface portion (41) of the cooling jacket (4); a second power module (32) mounted on a second surface portion (42) of the cooling jacket (4), the second surface portion (42) being opposite the first surface portion (41); and a third power module (33) mounted on a third surface part (400) of the cooling jacket (4), the third surface part (400) connecting one end of the first surface part (41) and one end of the second surface part (42), wherein the cooling jacket (4) comprises: a first slat (21) in contact with the first surface portion (41) in the passage; a second slat (22) in contact with the second surface portion (42) in the passage; a third slat (23) in contact with the third surface portion (400) in the passage; an inlet opening (1A) through which the coolant is admitted from the outside; an inlet manifold (7A) configured to direct the coolant entering from the inlet port (1A) to the first fin (21) and the second fin (22); an outlet opening (1B) through which the coolant is discharged to the outside; an outlet manifold (7B) configured to guide the coolant flowing through the first fin (21) and the second fin (22) to the outlet opening (1B), and wherein the first power module (31) and the second power module (32) are opposed to each other by the first surface part (41) and the second surface part (42) and by the first lamella (21) and the second lamella (22). [2] A semiconductor device according to claim 1, wherein the cooling jacket (4) further comprises a partition plate (81, 82, 83) separating the first fin (21) and the second fin (22) in the passage. [3] A semiconductor device according to claim 1 or 2, wherein the inlet manifold (7A) and the outlet manifold (7B) are arranged between the first fin (21) and the second fin (22). [4] The semiconductor device according to any one of claims 1 to 3, wherein the exhaust manifold (7B) is configured to guide the coolant flowing through the first fin (21) and the second fin (22) followed by the third fin (23) to the exhaust port (1B). [5] A semiconductor device according to any one of claims 1 to 4, wherein the first power module (31) and the second power module (32) each comprise a semiconductor element comprising a wide band gap power semiconductor element.

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