Semiconductor device and power conversion device

Abstract

The cooler (3) has a first main face (31). The joining material (7) is provided on the first main face (31). A groove (90) is provided on the first main face (31). When viewed in a first direction (101) from the joining material (7) toward the first main face (31), a portion of the groove (90) is provided between the fastening portion (5) and the joining material (7). The cooler (3) has a fastened region (50). In a second direction (102) from the fastened region (50) toward the joining material (7) in the shortest manner, in a case where a distance between the groove (90) and the joining material (7) is set as a first distance (D1) and a distance between the fastened region (50) and the groove (90) is set as a second distance (D2), the first distance (D1) is shorter than the second distance (D2).

Description

Technical Field

[0001] This disclosure relates to semiconductor devices and power conversion devices. Background Technology

[0002] As an example of a semiconductor device, Japanese Patent Application Publication No. 2012-142465 (Patent Document 1) discloses a semiconductor device comprising: a semiconductor module with a metal plate exposed on one side of a sealing member; and a heat dissipation member joined to the exposed surface of the metal plate via a bonding material. In this semiconductor device, the exposed metal plate in the semiconductor module is joined to a cooling device via the bonding material. The metal plate has a joined area and an unjoined non-joined area. The semiconductor device includes a resin agent. The resin agent is disposed in the non-joined area, the area surrounding the bonding material, and the area surrounding the joined portion in the cooling device.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2012-142465 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] According to the semiconductor module described in Patent Document 1, due to deformation of the cooler caused when the cooler and the sleeve are fastened, the resin sometimes peels off from the cooling device. Therefore, the resin cannot prevent the deterioration of the bonding material. As a result, the reliability of the semiconductor device decreases.

[0008] This disclosure was made in view of the above circumstances, and its purpose is to provide a semiconductor device and a power conversion device that can improve reliability.

[0009] Technical solutions adopted to solve technical problems

[0010] The semiconductor device disclosed herein includes a cooler, a bonding material, a first semiconductor module, and a fastening portion. The cooler has a first main surface. The bonding material is disposed on the first main surface. The first semiconductor module is disposed on the bonding material. The fastening portion fastens the cooler and the sleeve portion. A groove is provided on the first main surface. When viewed along a first direction from the bonding material toward the first main surface, a portion of the groove is disposed between the fastening portion and the bonding material. The cooler has a fastened area. The fastened area is formed by the area of ​​the cooler that contacts the fastening portion. When the distance between the groove and the bonding material in a second direction extending from the fastened area toward the bonding material in the shortest possible manner is defined as a first distance, and the distance between the fastened area and the groove is defined as a second distance, the first distance is shorter than the second distance.

[0011] Invention Effects

[0012] According to the semiconductor device disclosed herein, when the cooler and the sleeve are fastened, deformation of the portion of the cooler in contact with the bonding material can be suppressed. Therefore, a semiconductor device and a power conversion device with improved reliability can be provided. Attached Figure Description

[0013] Figure 1 This is a cross-sectional schematic diagram showing the structure of the semiconductor device according to Embodiment 1.

[0014] Figure 2 This is a first top view schematic diagram showing the structure of the semiconductor device according to Embodiment 1.

[0015] Figure 3 This is a second top view schematic diagram showing the structure of the semiconductor device according to Embodiment 1.

[0016] Figure 4 It is shown Figure 1 An enlarged schematic diagram of region IV.

[0017] Figure 5 This is a cross-sectional schematic diagram showing the structure of a comparative example semiconductor device.

[0018] Figure 6 It is shown Figure 5 An enlarged diagram of region VI.

[0019] Figure 7 This is a cross-sectional schematic diagram showing the state of cracks formed on the bonding material.

[0020] Figure 8 This is a cross-sectional schematic diagram showing the structure of a semiconductor device according to a variation of Embodiment 1.

[0021] Figure 9 This is a cross-sectional schematic diagram showing the structure of the semiconductor device according to Embodiment 2.

[0022] Figure 10 This is a top view schematic diagram showing the structure of the semiconductor device according to Embodiment 2.

[0023] Figure 11 This is a cross-sectional schematic diagram showing the structure of the semiconductor device according to Embodiment 3.

[0024] Figure 12 This is a cross-sectional schematic diagram showing the structure of a semiconductor device in a modified example of Embodiment 3.

[0025] Figure 13 This is a cross-sectional schematic diagram showing the structure of the semiconductor device according to Embodiment 4.

[0026] Figure 14 This is a cross-sectional schematic diagram showing the structure of the semiconductor device according to Embodiment 5.

[0027] Figure 15 This is a top view schematic diagram showing the structure of the semiconductor device according to Embodiment 5.

[0028] Figure 16 This is a cross-sectional schematic diagram showing the structure of a semiconductor device according to a first variation of Embodiment 5.

[0029] Figure 17 This is a cross-sectional schematic diagram showing the structure of a semiconductor device according to a second variation of Embodiment 5.

[0030] Figure 18 This is a top view schematic diagram showing the structure of a semiconductor device in a second variation of Embodiment 5.

[0031] Figure 19 This is a cross-sectional schematic diagram showing the structure of the semiconductor device according to Embodiment 6.

[0032] Figure 20 This is a cross-sectional schematic diagram showing the structure of the semiconductor device according to Embodiment 7.

[0033] Figure 21 This is a top view schematic diagram showing the structure of the semiconductor device according to Embodiment 7.

[0034] Figure 22 This is a cross-sectional schematic diagram showing the structure of the semiconductor device according to Embodiment 8.

[0035] Figure 23 This is a bottom view schematic diagram showing the structure of the cooler according to embodiment 8.

[0036] Figure 24 This is a block diagram showing the structure of a power conversion system using the power conversion device of embodiment 11. Detailed Implementation

[0037] Hereinafter, embodiments of the present disclosure will be described based on the accompanying drawings. Furthermore, in the following drawings, the same or equivalent parts will be labeled with the same reference numerals, and their descriptions will not be repeated.

[0038] Implementation method 1.

[0039] First, use Figure 1 and Figure 2 An example of the structure of the semiconductor device 10 according to Embodiment 1 is shown. For example... Figure 1 As shown, the semiconductor device 10 mainly includes a first semiconductor module 1, a cooler 3, a bonding material 7, a sleeve 4, a fastening part 5, and an elastomer 6.

[0040] Cooler 3 cools the first semiconductor module 1. Bonding material 7 bonds the first semiconductor module 1 to cooler 3. Sleeve 4 holds the coolant. Sleeve 4 is, for example, a water-cooling sleeve. Fastening part 5 fastens cooler 3 to sleeve 4. Fastening part 5 is, for example, an externally threaded part. Elastomer 6 seals the gap between sleeve 4 and cooler 3. Elastomer 6 is, for example, rubber. Elastomer 6 is, for example, an O-ring.

[0041] The cooler 3 is made of, for example, aluminum or copper. The cooler 3 is manufactured, for example, by forging. The cooler 3 has a plate portion 8 and a plurality of heat dissipation portions 9. The plate portion 8 has a first main surface 31 and a second main surface 32. The second main surface 32 is located on the opposite side of the first main surface 31. The plurality of heat dissipation portions 9 are connected to the plate portion 8 on the second main surface 32. Each of the plurality of heat dissipation portions 9 is, for example, pin-shaped. Specifically, each of the plurality of heat dissipation portions 9 is, for example, cylindrical. The plurality of heat dissipation portions 9 extend in a direction perpendicular to the second main surface 32. Specifically, the direction in which each of the plurality of heat dissipation portions 9 extends is perpendicular to a portion of the second main surface 32 to which each of the plurality of heat dissipation portions 9 is connected.

[0042] A bonding material 7 is disposed on the first main surface 31. The direction from the bonding material 7 toward the first main surface 31 is designated as the first direction 101. The bonding material 7 is disposed between the cooler 3 and the first semiconductor module 1. The bonding material 7 transfers heat generated in the first semiconductor module 1 to the cooler 3. The bonding material 7 is, for example, made of solder. The bonding material 7 may also be made of, for example, a high thermal conductivity adhesive or sintered silver.

[0043] The first semiconductor module 1 is disposed on the bonding material 7. The first semiconductor module 1 has an insulating substrate 30, a first semiconductor element 13, a second semiconductor element 14, a sealing material 20, a first terminal 18, a second terminal 19, a first internal bonding material 21, a second internal bonding material 22, a third internal bonding material 23, a fourth internal bonding material 24, and wiring 25.

[0044] An insulating substrate 30 is disposed on the bonding material 7. The insulating substrate 30 has an insulating layer 15, a first conductor pattern 11, and a second conductor pattern 12. The insulating layer 15 is made of ceramic, for example. The insulating layer 15 has a first surface 16 and a second surface 17. The second surface 17 is located on the opposite side of the first surface 16.

[0045] A first conductor pattern 11 is disposed on the first surface 16. The first conductor pattern 11 is bonded to the cooler 3 by a bonding material 7. The bonding material 7 is disposed between the cooler 3 and the first conductor pattern 11. A second conductor pattern 12 is disposed on the second surface 17.

[0046] A first internal bonding material 21 is disposed on the second conductor pattern 12. The first internal bonding material 21 bonds the second conductor pattern 12 to the first semiconductor element 13. The first semiconductor element 13 is electrically connected to the second conductor pattern 12. Specifically, the first semiconductor element 13 is electrically connected to the second conductor pattern 12 via the first internal bonding material 21.

[0047] A second internal bonding material 22 is disposed on the second conductor pattern 12. The second internal bonding material 22 bonds the second conductor pattern 12 to the second semiconductor element 14. The second semiconductor element 14 is electrically connected to the second conductor pattern 12. The first semiconductor element 13 and the second semiconductor element 14 are, for example, power semiconductor elements such as transistors, MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), and IGBTs (Insulated Gate Bipolar Transistors). Hereinafter, the first semiconductor element 13 and the second semiconductor element 14 will also be simply referred to as semiconductor elements.

[0048] Sealing material 20 seals the first semiconductor element 13, the second semiconductor element 14, and the insulating substrate 30. Specifically, sealing material 20 covers the insulating layer 15, the second conductor pattern 12, the first semiconductor element 13, and the second semiconductor element 14. Sealing material 20 covers a portion of the first conductor pattern 11. Alternatively, a portion of the first conductor pattern 11 is exposed from the sealing material 20. The exposed portion of the first conductor pattern 11 is in contact with the bonding material 7. Sealing material 20 is, for example, made of a resin material such as epoxy resin. The coefficient of linear expansion of sealing material 20 is, for example, smaller than that of the cooler 3. Specifically, the coefficient of linear expansion of the material constituting sealing material 20 is smaller than that of the material constituting cooler 3.

[0049] A portion of the first terminal 18 is covered by the sealing material 20. Alternatively, a portion of the first terminal 18 is exposed beyond the sealing material 20. The portion of the first terminal 18 covered by the sealing material 20 is electrically connected to the first semiconductor element 13 via wiring 25.

[0050] A portion of the second terminal 19 is covered by the sealing material 20. Alternatively, a portion of the second terminal 19 is exposed beyond the sealing material 20. The portion of the second terminal 19 covered by the sealing material 20 is electrically connected to the first semiconductor element 13 via a third internal bonding material 23. The portion of the second terminal 19 covered by the sealing material 20 is electrically connected to the second semiconductor element 14 via a fourth internal bonding material 24.

[0051] The first internal bonding material 21, the second internal bonding material 22, the third internal bonding material 23, and the fourth internal bonding material 24 are each made of solder or silver, etc. The wiring 25 is, for example, aluminum wire. The surface of the first terminal 18 may also be plated with nickel (Ni) or tin (Sn), etc. Similarly, the surface of the second terminal 19 may also be plated with nickel or tin, etc.

[0052] Figure 2 The structure of the cooler 3 and the bonding material 7 as viewed along the first direction 101 is shown. In other words, in Figure 2 In the diagram, the first semiconductor module 1 and the fastening part 5 are not shown. Figure 2 As shown, the cooler 3 has a fastened area 50. The fastened area 50 is formed by the fastening part 5 (see reference). Figure 1 The area that contacts the cooler 3 is formed. The fastened area 50 is, for example, part of the first main surface 31.

[0053] The fastened area 50 has four first portions 51. The four first portions 51 are separated from each other. The four first portions 51 are respectively fastened to four different fastening parts 5 (see reference). Figure 1 The area in contact with cooler 3. Figure 2 The image shows a quadrilateral 98 formed by connecting four first parts 51. When viewed along the first direction 101, the quadrilateral 98 is formed by connecting the centers of the first parts 51.

[0054] A groove 90 is provided on the first main surface 31. When viewed along the first direction 101, the groove 90 is, for example, annular. When viewed along the first direction 101, the groove 90, for example, surrounds the bonding material 7. When viewed along the first direction 101, the groove 90 is located inside the quadrilateral 98. From another viewpoint, when viewed along the first direction 101, the outer edge of the quadrilateral 98 is separated from the groove 90. The groove 90, for example, has a first groove portion 91 and a third groove portion 93.

[0055] When viewed along the first direction 101, the first groove 91 is disposed between the fastening part 5 and the bonding material 7. Specifically, the first groove 91 is disposed between at least one fastening part 5 and the bonding material 7. When viewed along the first direction 101, the shape of the first groove 91 is, for example, C-shaped.

[0056] When viewed along the first direction 101, the third groove 93 is located on the opposite side of the first groove 91 relative to the bonding material 7. From another viewpoint, when viewed along the first direction 101, the bonding material 7 is disposed between the first groove 91 and the third groove 93. When viewed along the first direction 101, the third groove 93 is, for example, straight.

[0057] The second direction 102 is defined as the direction from the fastened region 50 toward the bonding material 7 in the shortest possible way. Specifically, the second direction 102 is, for example, the direction from the first portion 51 closest to the bonding material 7 toward the bonding material 7. From another perspective, the second direction 102 is the direction extended by the shortest line segment 97 connecting the point on the outer edge of the fastened region 50 to the point on the outer edge of the bonding material 7.

[0058] When viewed along the first direction 101, the distance in the second direction 102 between the groove 90 and the bonding material 7 is defined as the first distance D1. When viewed along the first direction 101, the distance in the second direction 102 between the fastened area 50 and the groove 90 is defined as the second distance D2. The first distance D1 is shorter than the second distance D2.

[0059] exist Figure 3 In the image, a single-dotted line indicates the portion of the elastomer 6 in contact with the cooler 3. From another perspective, in... Figure 3 In the diagram, a single-dotted line indicates the contact surface between the elastomer 6 and the cooler 3. (For example...) Figure 3 As shown, when viewed along the first direction 101, the elastomer 6 is located between the fastener 5 and the bonding material 7. When viewed along the first direction 101, the shortest distance from the contact surface between the elastomer 6 and the cooler 3 to the groove 90 in the second direction 102 is defined as the third distance D3. The first distance D1 is shorter than the third distance D3. The third distance D3 is shorter than the second distance D2.

[0060] like Figure 1 As shown, the plate portion 8 has a first plate member 80, a first plate member 81, a third plate member 83, a middle portion 86, and an outer peripheral portion 87. The first plate member 80 is in contact with the bonding material 7. The first plate member 80 forms the side of the groove 90. A plurality of heat dissipation portions 9 are connected to the first plate member 80, for example.

[0061] The first plate member 81 is connected to the first flat plate member 80. The first plate member 81 forms the bottom surface of the first groove 91. From another viewpoint, the first plate member 81 is located between the bottom surface of the first groove 91 and the second main surface 32. The first plate member 81 is inclined, for example, in a first direction 101 relative to the first flat plate member 80.

[0062] The third plate member 83 is connected to the first plate member 80. The third plate member 83 forms the bottom surface of the third groove 93. From another viewpoint, the third plate member 83 is located between the bottom surface of the third groove 93 and the second main surface 32. The third plate member 83 is inclined, for example, in a first direction 101 relative to the first plate member 80.

[0063] The intermediate portion 86 is connected to the first groove portion 91 and the third groove portion 93, respectively. When viewed along the first direction 101, the intermediate portion 86 surrounds the first flat plate member 80, the first groove portion 91, and the third groove portion 93. The intermediate portion 86 is inclined, for example, relative to the first flat plate member 80 in the first direction 101.

[0064] The outer peripheral portion 87 is connected to the middle portion 86. The outer peripheral portion 87 surrounds the middle portion 86. The outer peripheral portion 87 is the part that contacts the sleeve portion 4 and the elastic body 6. The outer peripheral portion 87 is, for example, flat. A plurality of fastening holes 99 are provided on the outer peripheral portion 87. The fastening part 5 is inserted into the fastening hole 99. The outer peripheral portion 87 constitutes the fastened area 50.

[0065] like Figure 4 As shown, in the cross-section intersecting the first groove 91, the third groove 93, and the first conductor pattern 11, the direction from the first groove 91 toward the third groove 93 is designated as a third direction 103. In the third direction 103, the distance between the first groove 91 and the third groove 93 (fourth distance D4) is longer than the length of the first conductor pattern 11 (first length L1). In the third direction 103, the fourth distance D4 is longer than the length of the bonding material 7 (second length L2). The third direction 103 is perpendicular to the direction in which the third groove 93 extends.

[0066] In this specification, the groove depth F is the depth of the groove 90 in the thickness direction from the first main surface 31 toward the second main surface 32 and along the side of the groove 90. The groove width E is the width of the groove 90 in the direction perpendicular to the direction in which the groove 90 extends when viewed along the first direction 101. The groove depth F is, for example, less than the groove width E.

[0067] like Figure 1 As shown, a receiving portion 49 is provided on the sleeve portion 4. The receiving portion 49 holds the cooler 3. Multiple heat dissipation portions 9 are located in the receiving portion 49. The sleeve portion 4 has a support surface 41. The support surface 41 contacts the second main surface 32 of the cooler 3. For example, an internal thread 42 and a retaining groove 43 are provided on the support surface 41. A fastening portion 5 is inserted into the internal thread 42. An elastic body 6 is located in the retaining groove 43. The elastic body 6 contacts the second main surface 32 of the cooler 3. In addition, Figure 1 The sectional view shown is along Figure 2 A combined sectional view of line II.

[0068] Next, the effects of the semiconductor device 10 in Embodiment 1 will be explained.

[0069] First, use Figure 5 and Figure 6 The structure of the comparative example semiconductor device 10 will be described. Figure 5As shown, in the cooler 3 of the comparative example semiconductor device 10, the groove 90 is not provided. Due to the fastening force applied to the cooler 3 from the fastening part 5, a reaction force is applied to the cooler 3 from the sleeve part 4. Therefore, the cooler 3 deforms due to the fastening between the cooler 3 and the sleeve part 4. As a result, according to the comparative example semiconductor device, the cooler bends in a direction opposite to the first direction 101. Therefore, as Figure 6 As shown, due to the deformation of the cooler 3, stress is applied to the bonding material 7 in the direction of arrow A. From another perspective, due to the deformation of the cooler 3, the bonding material 7 is stretched by the cooler 3 and the first semiconductor module 1.

[0070] According to the semiconductor device 10 of Embodiment 1, by providing the groove 90, the rigidity of the portion of the cooler 3 near the groove 90 can be reduced. Therefore, when the cooler 3 deforms due to the fastening force, the portion of the cooler 3 near the groove 90 deforms preferentially. Thus, deformation at the portion of the cooler 3 in contact with the bonding material 7 is suppressed. Therefore, stress on the bonding material 7 can be mitigated. Thus, the reliability of the semiconductor device 10 can be improved.

[0071] Furthermore, according to the semiconductor device 10 of Embodiment 1, when viewed along the first direction 101, the distance (first distance D1) in the second direction 102 between the groove 90 and the bonding material 7 is shorter than the distance (second distance D2) in the second direction 102 between the fastened region 50 and the groove 90. Therefore, the length of the portion of the cooler 3 located between the fastening portion 5 and the groove 90 can be sufficiently long. Consequently, when the cooler 3 deforms due to the applied fastening force, energy that cannot be completely absorbed by the deformation of the portion of the cooler 3 near the groove 90 can be dissipated through the deformation of the portion of the cooler 3 located between the fastening portion 5 and the groove 90. Therefore, deformation at the portion of the cooler 3 in contact with the bonding material 7 can be effectively suppressed. As a result, the reliability of the semiconductor device 10 can be improved.

[0072] To prevent coolant leakage, an elastic body 6 is sometimes installed between the cooler 3 and the sleeve 4. In this case, due to the fastening of the cooler 3 and the sleeve 4, a reaction force is applied to the cooler 3 from the elastic body 6. Through this reaction force and the reaction force applied to the cooler 3 from the sleeve 4, the cooler 3 deforms.

[0073] According to the semiconductor device 10 of Embodiment 1, when viewed along the first direction 101, the distance (first distance D1) in the second direction 102 between the groove 90 and the bonding material 7 is shorter than the shortest distance (third distance D3) from the contact surface between the elastomer 6 and the cooler 3 to the groove 90 in the second direction 102. Therefore, the portion of the cooler 3 located between the contact surface and the groove 90 can be made sufficiently long. As a result, when the cooler 3 deforms due to the reaction force applied to the cooler 3 from the elastomer 6, the energy consumed by the deformation of the portion of the cooler 3 located between the contact surface and the groove 90 can be increased. Therefore, deformation at the portion of the cooler 3 in contact with the bonding material 7 can be effectively suppressed. As a result, the reliability of the semiconductor device 10 can be effectively improved.

[0074] like Figure 7 As shown, cracks C sometimes occur in the bonding material 7. Furthermore, during the operation of the semiconductor device 10, these cracks C sometimes propagate. Typically, the crack C propagates from the end of the bonding material 7 towards its center in an in-plane direction perpendicular to the first direction 101. When the crack C propagates directly below the semiconductor element, the efficiency of heat transfer from the semiconductor element to the cooler 3 is excessively reduced. Therefore, when the distance (crack tolerance B) from the end of the bonding material 7 to the semiconductor element in the in-plane direction perpendicular to the first direction 101 is short, the lifespan of the semiconductor device 10 is shortened.

[0075] According to the semiconductor device 10 of Embodiment 1, in a third direction 103 from the first trench 91 to the third trench 93, the distance between the first trench 91 and the third trench 93 (fourth distance D4) is longer than the length of the first conductor pattern 11 (first length L1). Therefore, compared to the case where the fourth distance D4 is shorter than the first length L1, the length of the bonding material 7 in the third direction 103 can be increased. As a result, the crack tolerance B can be increased. Consequently, the lifespan of the semiconductor device 10 can be extended.

[0076] When the semiconductor device 10 is driven, a difference in thermal expansion occurs between the semiconductor module and the cooler 3. Specifically, when the semiconductor device 10 is driven, heat emitted by the semiconductor element is transferred to the insulating substrate 30, the sealing material 20, and the cooler 3. As a result, when the temperature of each component of the semiconductor device 10 rises, a difference in thermal expansion occurs between the components due to their different coefficients of linear expansion. When a difference in thermal expansion occurs between the semiconductor module and the cooler 3, the stress generated by this difference in thermal expansion is applied to the bonding material 7.

[0077] According to Embodiment 1, the semiconductor device 10 has a groove 90 on the first main surface 31 of the cooler 3. Therefore, when a difference in thermal expansion occurs between the semiconductor module and the cooler 3, the portion of the cooler 3 closest to the groove 90 deforms preferentially. This reduces the difference in deformation between the bonding material 7 and the cooler 3 around the bonding material 7. Consequently, the stress on the bonding material 7 caused by the difference in thermal expansion can be mitigated. As a result, the reliability of the semiconductor device 10 can be effectively improved.

[0078] According to Embodiment 1, when viewed along the first direction 101, the groove 90 surrounds the bonding material 7 in the semiconductor device 10. Therefore, the stress on the bonding material 7 caused by the difference in thermal expansion can be mitigated more effectively.

[0079] According to the semiconductor device 10 of Embodiment 1, the first semiconductor module 1 has an insulating layer 15. The insulating layer 15 is made of ceramic. Generally, when the insulating layer 15 is made of ceramic, the difference between the thermal expansion of the first semiconductor module 1 and the thermal expansion of the cooler 3 increases. Therefore, the reliability of the semiconductor device 10 decreases. According to the semiconductor device 10 of Embodiment 1, even when the insulating layer 15 is made of ceramic, as described above, the stress of the bonding material 7 can be sufficiently mitigated. Therefore, the decrease in the reliability of the semiconductor device 10 can be suppressed.

[0080] According to the semiconductor device 10 of Embodiment 1, the coefficient of linear expansion of the sealing material 20 of the first semiconductor module 1 is less than that of the cooler 3. Normally, when the coefficient of linear expansion of the sealing material 20 is less than that of the cooler 3, the difference between the thermal expansion of the first semiconductor module 1 and the thermal expansion of the cooler 3 increases. Therefore, the reliability of the semiconductor device 10 decreases. According to the semiconductor device 10 of Embodiment 1, even when the coefficient of linear expansion of the sealing material 20 is less than that of the cooler 3, as described above, the stress on the bonding material 7 can be sufficiently mitigated. Therefore, the decrease in the reliability of the semiconductor device 10 can be suppressed.

[0081] According to the semiconductor device 10 of Embodiment 1, when viewed along the first direction 101, the groove 90 is provided on the inner side of the quadrilateral 98 formed by connecting the four first portions 51 of the fastening region 50. When viewed along the first direction 101, the outer edge of the quadrilateral 98 is located on the portion where the support surface 41 of the sleeve 4 overlaps with the cooler 3, and is a location where the fastening force applied to the cooler 3 from the multiple fastening portions 5 is easily concentrated. Therefore, when viewed along the first direction 101, when the groove 90 overlaps with the outer edge of the quadrilateral 98, coolant leakage may sometimes occur due to deformation of the portion of the cooler 3 near the groove 90. According to the semiconductor device 10 of Embodiment 1, by providing the groove 90 on the inner side of the quadrilateral 98, deformation of the portion of the cooler 3 near the groove 90 can be suppressed. Thus, coolant leakage can be effectively suppressed.

[0082] A variation of implementation method 1.

[0083] Next, use Figure 8 The structure of the semiconductor device 10 in a modified example of Embodiment 1 will be described. Figure 8 As shown, the trench depth F can also be greater than the trench width E. Therefore, assuming the trench width E is the same, compared to the case where the trench depth F is less than the trench width E, the rigidity of the portion of the cooler 3 near the trench 90 can be further reduced. Therefore, compared to the case where the trench depth F is less than the trench width E, the trench width E can be reduced while maintaining the effect of mitigating the stress of the bonding material 7. As a result, the semiconductor device 10 can be miniaturized.

[0084] Implementation method 2.

[0085] Next, use Figure 9 and Figure 10 The structure of the semiconductor device 10 according to Embodiment 2 will be described. The semiconductor device 10 of Embodiment 2 differs from the semiconductor device 10 of Embodiment 1 mainly in that it has multiple semiconductor modules and that the slot 90 has a second slot portion 92; otherwise, it is substantially the same as the semiconductor device 10 of Embodiment 1. Hereinafter, the description will focus on the differences from the semiconductor device 10 of Embodiment 1. Furthermore, Figure 9 The cross section shown is along Figure 10 A combined sectional view of the IX-IX lines.

[0086] like Figure 9 As shown, the semiconductor device 10 of Embodiment 2 has a plurality of semiconductor modules. Specifically, the semiconductor device 10 has a second semiconductor module 2. The structure of the second semiconductor module 2 may be substantially the same as the structure of the first semiconductor module 1. Hereinafter, the first semiconductor module 1 and the second semiconductor module 2 will also be referred to simply as semiconductor modules.

[0087] The bonding material 7 has a first bonding material portion 71 and a second bonding material portion 72. The first bonding material portion 71 is disposed between the first semiconductor module 1 and the cooler 3. From another viewpoint, the first semiconductor module 1 is disposed on the first bonding material portion 71. The first bonding material portion 71 bonds the first semiconductor module 1 to the cooler 3.

[0088] The second bonding material portion 72 is disposed between the second semiconductor module 2 and the cooler 3. Alternatively, the second semiconductor module 2 is disposed on the second bonding material portion 72. The second bonding material portion 72 bonds the second semiconductor module 2 to the cooler 3.

[0089] Plate portion 8 has a second plate member 89. The second plate member 89 is in contact with the second bonding material portion 72. The first plate member 80 is in contact with the first bonding material portion 71. The second plate member 89 is separate from the first plate member 80.

[0090] like Figure 9 and Figure 10 As shown, the groove 90 has a second groove portion 92. The second groove portion 92 is different from the first groove portion 91 and the third groove portion 93. Figure 10 As shown, when viewed along the first direction 101, the second groove 92 is disposed between the first bonding material portion 71 and the second bonding material portion 72. The second groove 92 is connected to the first groove 91. When viewed along the first direction 101, the second groove 92 is, for example, straight.

[0091] When viewed along the first direction 101, the first bonding material portion 71 is surrounded by the first groove portion 91 and the second groove portion 92. When viewed along the first direction 101, the second bonding material portion 72 is surrounded by the first groove portion 91, the second groove portion 92 and the third groove portion 93.

[0092] like Figure 9 As shown, plate portion 8 has a second plate member 82. The second plate member 82 is located between the first plate member 80 and the second plate member 89. Alternatively, the first plate member 80 is located between the first plate member 81 and the second plate member 82. The second plate member 89 is located between the second plate member 82 and the third plate member 83. The second plate member 82 is connected to both the first plate member 80 and the second plate member 89. The second plate member 82 forms the bottom surface of the second groove portion 92. Alternatively, the second plate member 82 is located between the bottom surface of the second groove portion 92 and the second main surface 32.

[0093] Compared to the case where there is only one semiconductor module, the overall heat generation of the semiconductor device 10 increases when multiple semiconductor modules are bonded to the cooler 3. Therefore, compared to the case where there is only one semiconductor module, the stress on the bonding material 7 caused by the difference in thermal expansion between the semiconductor modules and the cooler 3 increases. Furthermore, due to thermal interference from the heat generated by each of the multiple semiconductor modules, the portion of the cooler 3 located between the multiple semiconductor modules, when viewed along the first direction 101, tends to experience a higher temperature compared to other portions of the cooler 3. Therefore, when the semiconductor device 10 is driven, the portion of the cooler 3 located between the multiple semiconductor modules, when viewed along the first direction 101, is prone to deformation.

[0094] According to the semiconductor device 10 of Embodiment 2, the trench 90 has a second trench portion 92. When viewed along the first direction 101, the second trench portion 92 is disposed between the first bonding material portion 71 and the second bonding material portion 72. Therefore, when the semiconductor device 10 is driven, the portion of the cooler 3 closest to the second trench portion 92 deforms preferentially. As a result, deformation of the portion of the cooler 3 in contact with the bonding material 7 can be effectively suppressed. Therefore, while suppressing the increase in the size of the semiconductor device 10, the stress on the bonding material 7 can be effectively mitigated. As a result, the reliability of the semiconductor device 10 can be effectively improved.

[0095] Implementation method 3.

[0096] Next, use Figure 11 The structure of the semiconductor device 10 according to Embodiment 3 will be described. The semiconductor device 10 of Embodiment 3 differs from the semiconductor device 10 of Embodiment 2 mainly in that the leakage of coolant is effectively suppressed; otherwise, it is substantially the same as the semiconductor device 10 of Embodiment 1. Hereinafter, the description will focus on the differences from the semiconductor device 10 of Embodiment 2.

[0097] like Figure 11 As shown, the thickness T of the plate portion 8 of the cooler 3 is the thickness T of the plate portion 8 in the thickness direction from the first main surface 31 to the second main surface 32. Specifically, the thickness T is the thickness T at the thickest part of the plate portion 8 in the thickness direction. The groove depth F is less than half the thickness T of the plate portion 8. From another perspective, in the thickness direction, the thickness of each of the first plate member 81, the second plate member 82, and the third plate member 83 is greater than half the thickness T of the plate portion 8. The thickness T of the plate portion 8 is, for example, 2 mm or more. The thickness T may also be, for example, 3 mm or more, or 5 mm or more.

[0098] To ensure stable operation of the semiconductor device 10, it is necessary to suppress leakage of the coolant flowing between the sleeve 4 and the cooler 3. To suppress coolant leakage, it is necessary to prevent gaps from forming between the cooler 3 and the sleeve 4 due to deformation of the cooler 3.

[0099] According to the semiconductor device 10 of embodiment 3, the trench depth F is less than half the thickness T of the plate portion 8. Therefore, excessive deformation of the cooler 3 near the trench 90 can be suppressed. As a result, the formation of a gap between the cooler 3 and the sleeve portion 4 due to deformation of the cooler 3 can be suppressed. Therefore, coolant leakage can be suppressed. As a result, the stability of the operation of the semiconductor device 10 can be improved.

[0100] According to the semiconductor device 10 of Embodiment 3, the thickness T of the plate portion 8 is 2 mm or more. This effectively suppresses deformation of the cooler 3. Consequently, coolant leakage is effectively suppressed. As a result, the operational stability of the semiconductor device 10 is effectively improved.

[0101] A variation of implementation method 3.

[0102] Next, use Figure 12 The structure of the semiconductor device 10 in a modified example of Embodiment 3 will be described. Figure 12 As shown, the semiconductor device 10 may also have a third bonding material portion 73. From another perspective, the semiconductor device 10 may also have three semiconductor modules (not shown). The third bonding material portion 73 is the bonding material 7 (see reference 7). Figure 10 Part of ). The first bonding material part 71, the second bonding material part 72 and the third bonding material part 73 are arranged in a row, for example.

[0103] The groove 90 may also have a sixth groove portion 96. When viewed along the first direction 101, the sixth groove portion 96 is disposed between the second bonding material portion 72 and the third bonding material portion 73. The sixth groove portion 96 is connected to the first groove portion 91. When viewed along the first direction 101, the sixth groove portion 96 is disposed between the second groove portion 92 and the third groove portion 93. When viewed along the first direction 101, the sixth groove portion 96 is, for example, straight. When viewed along the first direction 101, the direction in which the sixth groove portion 96 extends may be parallel to the direction in which the third groove portion 93 extends.

[0104] The fastened area 50 of the cooler 3 may also have more than one second part 52. Specifically, the fastened area 50 may have, for example, two second parts 52. Each of the two second parts 52 is a different area from the four first parts 51. From another perspective, the cooler 3 and the sleeve 4 are fastened by six fastening parts 5 (see reference). Figure 11 It was fastened.

[0105] When viewed along the first direction 101, the two second parts 52 are, for example, respectively disposed on the outer edge of the quadrilateral 98. From another perspective, when viewed along the first direction 101, by connecting the first part 51 and the second part 52, a quadrilateral 98 can be formed, for example. Alternatively, when viewed along the first direction 101, the two second parts 52 can also be respectively disposed on the inner side of the quadrilateral 98.

[0106] When the number of semiconductor modules in the semiconductor device 10 increases, resulting in a longer length of the cooler 3, the number of fastening parts 5 is sometimes set to five or more in order to suppress coolant leakage. According to the first variation of embodiment 3, even when the number of fastening parts 5 is five or more, deformation of the portion of the cooler 3 near the tank 90 can be suppressed. As a result, coolant leakage can be effectively suppressed.

[0107] Implementation method 4.

[0108] Next, use Figure 13 The semiconductor device 10 of Embodiment 4 differs from the semiconductor device 10 of Embodiment 2 mainly in that the plurality of heat dissipation portions 9 are respectively disposed in the first direction 101 relative to the slot 90; otherwise, it is substantially the same as the semiconductor device 10 of Embodiment 2. Hereinafter, the description will focus on the differences from the semiconductor device 10 of Embodiment 2.

[0109] like Figure 13 As shown, in the semiconductor device 10 according to Embodiment 4, at least one of the plurality of heat dissipation portions 9 is disposed in a first direction 101 relative to the groove 90. Specifically, at least one of the plurality of heat dissipation portions 9 is disposed in the first direction 101 relative to the first groove portion 91. From another viewpoint, at least one of the plurality of heat dissipation portions 9 is connected to the first plate member 81.

[0110] At least one of the plurality of heat dissipation portions 9 is disposed in the first direction 101 relative to the second groove portion 92. From another viewpoint, at least one of the plurality of heat dissipation portions 9 is connected to the second plate member 82. At least one of the plurality of heat dissipation portions 9 is disposed in the first direction 101 relative to the third groove portion 93. From another viewpoint, at least one of the plurality of heat dissipation portions 9 is connected to the third plate member 83.

[0111] In the portion of the cooler 3 near the slot 90, heat is less likely to transfer in the direction along the first main surface 31 compared to other portions of the cooler 3. According to the semiconductor device 10 of embodiment 4, at least one of the plurality of heat dissipation portions 9 is connected to the first plate member 81. Therefore, heat dissipation at the portion of the cooler 3 near the first slot 91 can be improved.

[0112] According to the semiconductor device 10 of embodiment 4, at least one of the plurality of heat dissipation portions 9 is connected to the second plate member 82. Therefore, the heat dissipation performance at the portion of the cooler 3 near the second slot portion 92 can be improved. The portion of the cooler 3 near the second slot portion 92 is the part where the temperature easily rises due to thermal interference from the heat emitted by two adjacent semiconductor modules. Therefore, by improving the heat dissipation performance at the portion of the cooler 3 near the second slot portion 92, the reliability of the semiconductor device 10 can be effectively improved.

[0113] Implementation method 5.

[0114] Next, use Figure 14 and Figure 15 The structure of the semiconductor device 10 according to Embodiment 5 will be described. The semiconductor device 10 of Embodiment 5 differs from the semiconductor device 10 of Embodiment 2 mainly in that the cooler 3 has a non-bonded region; otherwise, it is substantially the same as the semiconductor device 10 of Embodiment 2. Hereinafter, the description will focus on the differences from the semiconductor device 10 of Embodiment 2.

[0115] like Figure 14 and Figure 15 As shown, the cooler 3 has a first non-bonding region 56. The first non-bonding region 56 is disposed on the first main surface 31. The first non-bonding region 56 can suppress the wetting and spreading of the material constituting the bonding material 7. Specifically, when the material constituting the bonding material 7 (e.g., solder) melts, the first non-bonding region 56 can suppress the wetting and spreading of the molten material on the first non-bonding region 56.

[0116] In the semiconductor device 10 of Embodiment 5, when the cooler 3 is made of aluminum, the first non-bonded region 56 is, for example, a scale-free region of aluminum or a region coated with a photoresist. A scale-free region of aluminum is, for example, a region of the aluminum surface that has not undergone surface treatments such as photoresist coating, laser roughening, or plating. Alternatively, the first non-bonded region 56 may be, for example, a region covered by an aluminum oxide film.

[0117] In the case where the cooler 3 is made of copper, the first non-bonded area 56 is, for example, an area coated with a resist or an area that has undergone roughening using a laser.

[0118] like Figure 15As shown, when viewed along the first direction 101, the first non-joining region 56 is disposed between the groove 90 and the joining material 7. Specifically, when viewed along the first direction 101, the first non-joining region 56 is disposed between the first groove 91 and the second groove 92 and the first joining material 71, respectively. When viewed along the first direction 101, the first non-joining region 56 is disposed between the first groove 91, the second groove 92, and the third groove 93 and the second joining material 72, respectively. When viewed along the first direction 101, the first non-joining region 56 surrounds the first joining material 71 and the second joining material 72, respectively. When viewed along the first direction 101, the first non-joining region 56 is surrounded by the groove 90.

[0119] For example, when the bonding material 7 is made of solder, the material constituting the bonding material 7 melts when the semiconductor module is bonded to the cooler 3. In this case, due to the wetting and expansion of the molten material, the shape of the bonding material 7 may not be the desired shape.

[0120] According to the semiconductor device 10 of embodiment 5, the cooler 3 has a first non-bonding region 56. When viewed along the first direction 101, the first non-bonding region 56 is disposed between the groove 90 and the bonding material 7. Therefore, during the bonding of the semiconductor module and the cooler 3, when the material constituting the bonding material 7 melts, the occurrence of undesirable wetting and spreading of the material is suppressed. As a result, the occurrence of shape abnormalities of the bonding material 7 is suppressed. Consequently, the reliability of the semiconductor device 10 can be improved.

[0121] The first variation of implementation method 5.

[0122] Next, use Figure 16 The structure of the semiconductor device 10 in the first modification of Embodiment 5 will be described. Figure 16 As shown, the cooler 3 may also have a plating layer 59. The plating layer 59 covers at least a portion of the plate portion 8 and the plurality of heat dissipation portions 9. The plating layer 59 may also cover the entire plate portion 8 and the plurality of heat dissipation portions 9. The plating layer 59 is made of, for example, nickel. The surface of the cooler 3 is, for example, formed by the plating layer 59 and a first non-bonded region 56.

[0123] In the semiconductor device 10 of the first variation of embodiment 5, the first non-bonded region 56 may be, for example, a region on the plating layer 59 coated with a photoresist. The first non-bonded region 56 may also be, for example, a scale-free region of aluminum not covered by the plating layer 59. The first non-bonded region 56 may also be a region not covered by the plating layer 59 that has undergone roughening processing using a laser.

[0124] For example, when the plate portion 8 and the plurality of heat dissipation portions 9 are made of copper, the plate portion 8 and the plurality of heat dissipation portions 9 may sometimes corrode due to impurities in the coolant. According to the semiconductor device 10 of the first modification of embodiment 5, the cooler 3 has a plating layer 59, thereby suppressing corrosion of the plate portion 8 and the plurality of heat dissipation portions 9. As a result, the reliability of the semiconductor device 10 can be improved.

[0125] The second variation of implementation method 5.

[0126] Next, use Figure 17 and Figure 18 The structure of the semiconductor device 10 in the second modification of Embodiment 5 will be described. Figure 17 and Figure 18 As shown, the cooler 3 may also have a second non-bonding region 57. The second non-bonding region 57 is capable of suppressing the wetting and spreading of the material constituting the bonding material 7. The second non-bonding region 57 is connected to the first non-bonding region 56. The position of the second non-bonding region 57 differs from that of the first non-bonding region, but in other respects, the structure of the second non-bonding region 57 is substantially the same as that of the first non-bonding region 56.

[0127] like Figure 17 As shown, the second non-jointing region 57 covers both the bottom surface and the side surface of the groove 90. From another perspective, the second non-jointing region 57 is disposed within the groove 90. Figure 18 As shown, when viewed along the first direction 101, the second non-bonding region 57 surrounds the first bonding material portion 71 and the second bonding material portion 72, respectively.

[0128] During the bonding of the semiconductor module and the cooler 3, when the material constituting the bonding material 7 melts, this material sometimes flows into the tank 90. ​​In this case, the solidified material hinders the deformation of the portion of the cooler 3 near the tank 90. ​​Therefore, the reliability of the semiconductor device 10 is sometimes not sufficiently improved.

[0129] According to the second variation of embodiment 5, the second non-bonding region 57 covers the bottom surface and the side surface of the groove 90, thereby preventing the molten material constituting the bonding material 7 from entering the groove 90. As a result, the reliability of the semiconductor device 10 can be stably improved.

[0130] Furthermore, similar to the semiconductor device 10 of the first modification of Embodiment 5, in the semiconductor device 10 of the second modification of Embodiment 5, the cooler 3 may also have a plating layer 59. The surface of the cooler 3 may, for example, be composed of the plating layer 59, a first non-bonded region 56, and a second non-bonded region 57.

[0131] Implementation method 6.

[0132] Next, use Figure 19 The structure of the semiconductor device 10 according to Embodiment 6 will be described. The semiconductor device 10 of Embodiment 6 differs from the semiconductor device 10 of Embodiment 1 mainly in that the sealing material 20 has a protrusion 28; otherwise, it is substantially the same as the semiconductor device 10 of Embodiment 1. Hereinafter, the description will focus on the differences from the semiconductor device 10 of Embodiment 1.

[0133] like Figure 19 As shown, in the semiconductor device 10 of Embodiment 6, the sealing material 20 may also have a main body portion 27 and a protrusion portion 28. The main body portion 27 is located relative to the contact surface between the first conductor pattern 11 and the bonding material 7 in a direction from the bonding material 7 toward the first conductor pattern 11. The direction from the bonding material 7 toward the first conductor pattern 11 is opposite to the first direction 101. The main body portion 27 covers the insulating layer 15, the second conductor pattern 12, the first semiconductor element 13, and the second semiconductor element 14. The main body portion 27 covers a portion of the first conductor pattern 11.

[0134] The protrusion 28 is connected to the main body 27. The protrusion 28 extends from the main body 27 toward the cooler 3. The direction from the main body 27 toward the cooler 3 is, for example, the same as the first direction 101. On the first main surface 31, the protrusion 28 contacts the cooler 3. The protrusion 28 surrounds the bonding material 7.

[0135] The sealing material 20 has protrusions 28, which can suppress the flow of the material constituting the bonding material 7, which melts during the bonding of the semiconductor module and the cooler 3, toward the groove 90. This steadily improves the reliability of the semiconductor device 10. In particular, when the warpage of the semiconductor module is large, more solder is sometimes supplied to prevent insufficient solder. In this case, molten solder easily enters the groove 90. Even in this situation, the semiconductor device 10 according to Embodiment 6 can steadily improve its reliability.

[0136] Implementation method 7.

[0137] Next, use Figure 20 and Figure 21 The structure of the semiconductor device 10 according to Embodiment 7 will be described. The semiconductor device 10 of Embodiment 7 differs from the semiconductor device 10 of Embodiment 2 mainly in that the trench 90 has a fourth trench portion 94 and a fifth trench portion 95; otherwise, it is substantially the same as the semiconductor device 10 of Embodiment 2. Hereinafter, the description will focus on the differences from the semiconductor device 10 of Embodiment 2.

[0138] like Figure 20 and Figure 21As shown, in the semiconductor device 10 of Embodiment 7, the trench 90 has a fourth trench portion 94 and a fifth trench portion 95. The fourth trench portion 94 is disposed in the middle portion 86. The fourth trench portion 94 is different from the first trench portion 91, the second trench portion 92, and the third trench portion 93. The fifth trench portion 95 is disposed in the middle portion 86. The fifth trench portion 95 is different from the first trench portion 91, the second trench portion 92, the third trench portion 93, and the fourth trench portion 94.

[0139] like Figure 21 As shown, when viewed along the first direction 101, the fourth groove 94 is disposed between the fastening portion 5 and the first groove 91. When viewed along the first direction 101, the fourth groove 94 is disposed on the opposite side of the bonding material 7 relative to the first groove 91. The fourth groove 94 is, for example, separate from the first groove 91 and the third groove 93. When viewed along the first direction 101, the fourth groove 94 is straight. When viewed along the first direction 101, the direction in which the fourth groove 94 extends may be parallel to the direction in which the third groove 93 extends.

[0140] When viewed along the first direction 101, the fifth groove 95 is disposed between the fastening portion 5 and the third groove 93. When viewed along the first direction 101, the fifth groove 95 is disposed on the opposite side of the bonding material 7 relative to the third groove 93. The fifth groove 95 is, for example, separate from both the first groove 91 and the third groove 93. When viewed along the first direction 101, the fifth groove 95 is straight. When viewed along the first direction 101, the direction in which the fifth groove 95 extends may be parallel to the direction in which the third groove 93 extends.

[0141] According to the semiconductor device 10 of Embodiment 7, by providing a fourth groove 94, the deformation of the portion of the cooler 3 near the first groove 91 can be reduced. This suppresses fatigue in the portion of the cooler 3 near the first groove 91. Similarly, by providing a fifth groove 95, fatigue in the portion of the cooler 3 near the third groove 93 can be suppressed.

[0142] Alternatively, more than one groove may be provided between the fourth groove 94 and the first groove 91. Similarly, more than one groove may be provided between the fifth groove 95 and the third groove 93.

[0143] Implementation method 8.

[0144] Next, use Figure 22 and Figure 23 The structure of the semiconductor device 10 according to Embodiment 8 will be described. The semiconductor device 10 of Embodiment 8 differs from the semiconductor device 10 of Embodiment 2 mainly in the shape of each of the plurality of heat sinks 9; otherwise, it is substantially the same as the semiconductor device 10 of Embodiment 2. Hereinafter, the description will focus on the differences from the semiconductor device 10 of Embodiment 2. Furthermore, for ease of explanation, in... Figure 22 In the middle, the sleeve part 4 and the fastening part 5 are not shown. Figure 23 The structure of the cooler 3 is shown when viewed in a direction perpendicular to the second main surface 32.

[0145] like Figure 22 and Figure 23 As shown, in the semiconductor device 10 according to Embodiment 8, the plurality of heat dissipation portions 9 are each polygonal prism-shaped. Figure 22 As shown, the plate portion 8 has a main body member 33 and a connecting plate member 34. The main body member 33 forms part of the second main surface 32 and the first main surface 31. Various grooves 90 and fastening holes 99 are provided on the main body member 33.

[0146] The connecting plate member 34 connects the main body member 33 to the plurality of heat dissipation parts 9. In the first direction 101, the connecting plate member 34 is disposed between the main body member 33 and the plurality of heat dissipation parts 9. The connecting plate member 34 forms part of the second main surface 32. The connecting plate member 34 is, for example, surrounded by the sleeve part 4. The connecting plate member 34 is located within the receiving part 49 of the sleeve part 4.

[0147] like Figure 23 As shown, when viewed along the direction in which the plurality of heat dissipation sections 9 extend, each of the plurality of heat dissipation sections 9 has a polygonal shape. Specifically, when viewed along the direction in which the plurality of heat dissipation sections 9 extend, each of the plurality of heat dissipation sections 9 has, for example, a hexagonal shape. From another perspective, each of the plurality of heat dissipation sections 9 has a hexagonal prism shape. In addition, the polygonal shape includes the case where the corners of the shape are rounded (R). When viewed along the direction in which the plurality of heat dissipation sections 9 extend, one side of each of two adjacent heat dissipation sections 9 can be parallel to each other.

[0148] The second main surface 32 has an outer peripheral region 35 and a heat dissipation region 36. The outer peripheral region 35 is the region that contacts the sleeve portion 4. Specifically, the outer peripheral region 35 contacts the support surface 41 of the sleeve portion 4 (see reference). Figure 22 ) and elastomer 6 (refer to Figure 22 Contact. The outer peripheral region 35 is, for example, composed of the main body component 33.

[0149] The heat dissipation area 36 is surrounded by the outer peripheral area 35. Multiple heat dissipation sections 9 are provided within the heat dissipation area 36. The heat dissipation area 36 is, for example, formed by a connecting plate member 34. When viewed along the direction in which each of the multiple heat dissipation sections 9 extends, the shape of the heat dissipation area 36 is, for example, rectangular.

[0150] When viewed along the direction in which the multiple heat dissipation sections 9 extend, the total area of ​​the multiple heat dissipation sections 9 is defined as the first area. The first area is the value obtained by summing the areas of the multiple heat dissipation sections 9 individually. When viewed along the direction in which the multiple heat dissipation sections 9 extend, the area of ​​the heat dissipation region 36 is defined as the second area. When the shape of the heat dissipation region 36 is rectangular when viewed along the direction in which the multiple heat dissipation sections 9 extend, the second area is the value obtained by multiplying the height H of the heat dissipation region 36 by the width W of the heat dissipation region 36. The second area is the value obtained by adding the first area to the area of ​​the heat dissipation region 36 of the multiple heat dissipation sections 9 that do not overlap.

[0151] The value obtained by dividing the first area by the second area is 0.2 or higher. The value obtained by dividing the first area by the second area could also be 0.35 or higher, or 0.5 or higher. The value obtained by dividing the first area by the second area could also be 0.9 or lower, or 0.8 or lower.

[0152] According to Embodiment 8, in the semiconductor device 10, when viewed along the direction in which the plurality of heat sinks 9 extend, each of the plurality of heat sinks 9 has a polygonal shape. Therefore, compared to the case where each of the plurality of heat sinks 9 has a circular shape, the flow of coolant can be made more complex by providing corners on the heat sinks 9. Therefore, through the leading edge effect, the formation of a temperature boundary layer near the surface of each of the plurality of heat sinks 9 can be suppressed. As a result, the efficiency of heat exchange between the coolant and each of the plurality of heat sinks 9 can be improved. As a result, miniaturization and high density of the semiconductor device 10 can be promoted.

[0153] According to embodiment 8, when viewed along the direction in which the plurality of heat dissipation portions 9 extend, each of the plurality of heat dissipation portions 9 has a hexagonal shape. This effectively improves the efficiency of heat exchange between the coolant and each of the plurality of heat dissipation portions 9.

[0154] When viewed along the direction in which the plurality of heat dissipation portions 9 extend, if the total area (first area) of the plurality of heat dissipation portions 9 is too small, the heat transferred from each of the plurality of heat dissipation portions 9 to the coolant is excessively reduced. According to the semiconductor device 10 of Embodiment 8, the value obtained by dividing the first area by the second area is 0.2 or more. As a result, the heat transferred from each of the plurality of heat dissipation portions 9 to the coolant can be sufficiently large. As a result, the miniaturization and high density of the semiconductor device 10 can be effectively promoted.

[0155] Implementation method 9.

[0156] This embodiment, based on the semiconductor device 10 of embodiments 1 to 8 described above, uses a reverse-conducting insulated-gate bipolar transistor (RC-IGBT) as the semiconductor element. In other words, the semiconductor element can also be an RC-IGBT. By using an RC-IGBT as the semiconductor element, the number of semiconductor elements can be reduced. Therefore, the semiconductor module can be miniaturized. As a result, the semiconductor device 10 can be miniaturized.

[0157] Implementation method 10.

[0158] This embodiment uses silicon carbide (SiC) as the semiconductor element, based on the semiconductor device 10 of embodiments 1 to 8 described above. In other words, the semiconductor element can also be made of silicon carbide. The semiconductor element is made of SiC, which has relatively low loss, thereby promoting the miniaturization and high density of the semiconductor device 10.

[0159] Implementation method 11.

[0160] This embodiment applies the semiconductor devices described in Embodiments 1 to 10 to a power conversion device. This disclosure is not limited to any specific power conversion device, but Embodiment 11 will be used to describe the application of the present invention to a three-phase inverter.

[0161] Figure 24 This is a block diagram showing the structure of a power conversion system using the power conversion device of this embodiment.

[0162] Figure 24 The power conversion system shown consists of a power source 100, a power conversion device 200, and a load 300. The power source 100 is a DC power source, supplying DC power to the power conversion device 200. The power source 100 can be constructed from various devices, such as a DC system, solar cells, or batteries, or from a rectifier circuit or AC / DC converter connected to an AC system. Alternatively, the power source 100 can be constructed from a DC / DC converter that converts DC power output from a DC system into a specified power.

[0163] The power conversion device 200 is a three-phase inverter connected between the power source 100 and the load 300, which converts the DC power supplied from the power source 100 into AC power and supplies AC power to the load 300. Figure 24As shown, the power conversion device 200 includes: a main conversion circuit 201, which converts DC power into AC power and outputs it; a drive circuit 202, which outputs drive signals to drive each switching element of the main conversion circuit 201; and a control circuit 203, which outputs control signals to the drive circuit 202 to control the drive circuit 202.

[0164] Load 300 is a three-phase motor driven by AC power supplied from power conversion device 200. Furthermore, load 300 is not limited to a specific application and is a motor installed in various electrical equipment, such as motors used in hybrid vehicles, electric vehicles, railway vehicles, elevators, or air conditioning equipment.

[0165] The power conversion device 200 will now be described in detail. The main conversion circuit 201 includes switching elements and return diodes (not shown). Through the switching action of the switching elements, it converts the DC power supplied from the power source 100 into AC power and supplies it to the load 300. The specific circuit structure of the main conversion circuit 201 can vary, but in this embodiment, the main conversion circuit 201 is a dual-level three-phase full-bridge circuit, which can be constructed from six switching elements and six return diodes connected in anti-parallel to each switching element. Each switching element of the main conversion circuit 201 uses a semiconductor device from any of embodiments 1 to 10 described above. Each pair of the six switching elements is connected in series to form upper and lower arms, and each upper and lower arm constitutes a phase (U phase, V phase, W phase) of the full-bridge circuit. Furthermore, the output terminals of each upper and lower arm, i.e., the three output terminals of the main conversion circuit 201, are connected to the load 300.

[0166] The drive circuit 202 generates drive signals for the switching elements of the main conversion circuit 201 and supplies them to the control electrodes of the switching elements of the main conversion circuit 201. Specifically, based on the control signal from the control circuit 203 (described later), drive signals for setting the switching element to the ON state and drive signals for setting the switching element to the OFF state are output to the control electrodes of each switching element. When the switching element is kept in the ON state, the drive signal is a voltage signal above the threshold voltage of the switching element (ON signal); when the switching element is kept in the OFF state, the drive signal is a voltage signal below the threshold voltage of the switching element (OFF signal).

[0167] Control circuit 203 controls the switching elements of main conversion circuit 201 to supply the desired power to load 300. Specifically, based on the power to be supplied to load 300, it calculates the time (on-time) during which each switching element of main conversion circuit 201 should be in the on state. For example, main conversion circuit 201 can be controlled by PWM control that modulates the on-time of the switching elements according to the output voltage. Furthermore, control commands (control signals) are output to drive circuit 202 to output on-signals to the switching elements that should be in the on state at each time point and off-signals to the switching elements that should be in the off state. Drive circuit 202 outputs on-signals or off-signals as drive signals to the control electrodes of each switching element according to the control signal.

[0168] In the power conversion device of this embodiment, since the semiconductor device of embodiments 1 to 10 is used as the switching element of the main conversion circuit 201, the reliability can be improved.

[0169] In this embodiment, an example of applying the present invention to a two-level three-phase inverter has been described, but the present invention is not limited thereto and can be applied to various power conversion devices. In this embodiment, a two-level power conversion device is used, but it could also be a three-level or multi-level power conversion device. When supplying power to a single-phase load, the present invention can also be applied to a single-phase inverter. Furthermore, when supplying power to DC loads, the present invention can also be applied to DC / DC converters or AC / DC converters.

[0170] Furthermore, the power conversion device using the present invention is not limited to the case where the load is an electric motor. For example, it can also be used as a power supply device for electrical discharge machining, laser processing machine, or induction heating kitchen appliances, non-contact power supply system, and can also be used as a power regulator for solar power generation system, energy storage system, etc.

[0171] It should be considered that the embodiments disclosed herein are illustrative in all respects and not restrictive. The scope of this disclosure is defined by the claims rather than by the foregoing description and is intended to include all changes within the meaning and scope equivalent to the claims.

[0172] Symbol Explanation

[0173] 1 First semiconductor module; 2 Second semiconductor module; 3 Cooler; 4 Sleeve; 5 Fastening part; 6 Elastomer; 7 Bonding material; 8 Plate part; 9 Heat dissipation part; 10 Semiconductor device; 11 First conductor pattern; 12 Second conductor pattern; 13 First semiconductor element; 14 Second semiconductor element; 15 Insulating layer; 16 First surface; 17 Second surface; 18 First terminal; 19 Second terminal; 20 Sealing material; 21 First internal bonding material; 22 Second internal bonding material; 23 Third internal bonding material; 24 Fourth internal bonding material; 25 Wiring; 27 Main body; 28 Protrusion; 30 Insulating substrate; 31 First main surface; 32 Second main surface; 33 Main body component; 34 Connecting plate component; 35 Outer peripheral area; 36 Heat dissipation area; 41 Support surface; 42 Internal thread; 43 Retaining groove; 49 Receiving part; 50 Fastened area; 51 First part; 52 Second part; 56 57 First non-bonded area; 59 Second non-bonded area; 71 First bonding material part; 72 Second bonding material part; 73 Third bonding material part; 80 First flat plate member; 81 First plate member; 82 Second plate member; 83 Third plate member; 86 Middle part; 87 Outer periphery; 89 Second flat plate member; 90 Groove; 91 First groove; 92 Second groove; 93 Third groove; 94 Fourth groove; 95 Fifth groove; 96 Sixth groove; 97 Line segment; 98 Quadrilateral; 99 Fastening hole; 100 Power supply; 101 First direction; 102 Second direction; 103 Third direction; 200 Power conversion device; 201 Main conversion circuit; 202 Drive circuit; 203 Control circuit; 300 Load; A Arrow; B Crack tolerance; C Crack; D1 First distance; D2 Second distance; D3 Third distance; D4 Fourth distance; E Slot width; F Slot depth; H Height; L1 First length; L2 Second length; T Thickness; W Width.

Claims

1. A semiconductor device, characterized in that, include: A cooler having a first main surface; A bonding material is disposed on the first main surface; A first semiconductor module is disposed on the bonding material; as well as The fastening part secures the cooler and the sleeve. A groove is provided on the first main surface. When viewed along a first direction from the bonding material toward the first main surface, a portion of the groove is disposed between the fastening portion and the bonding material. The cooler has a fastening area, which is formed by the area of ​​the cooler that contacts the fastening part. The second direction is defined as the direction from the fastened area toward the bonding material in the shortest possible way. The distance in the second direction between the groove and the bonding material when viewed along the first direction is defined as the first distance. When the distance in the second direction between the fastened area and the groove is taken as the second distance when viewed along the first direction, the first distance is shorter than the second distance.

2. The semiconductor device according to claim 1, characterized in that, The semiconductor device further includes a second semiconductor module that is different from the first semiconductor module. The bonding material has the following characteristics: A first bonding material portion is disposed between the cooler and the first semiconductor module; and The second bonding material portion is disposed between the cooler and the second semiconductor module. The groove has a second groove portion that is different from the first portion. When viewed along the first direction, the second groove is disposed between the first bonding material portion and the second bonding material portion.

3. The semiconductor device according to claim 1 or 2, characterized in that, Also includes: The sleeve; as well as An elastomer, wherein the elastomer is sandwiched between the cooler and the sleeve. When viewed along the first direction, the elastomer is located between the fastening portion and the bonding material. When the shortest distance from the contact surface between the elastomer and the cooler to the groove in the second direction is set as the third distance, the first distance is shorter than the third distance.

4. The semiconductor device according to any one of claims 1 to 3, characterized in that, The first semiconductor module has: An insulating layer having a first surface and a second surface located on the opposite side of the first surface; A first conductor pattern is disposed on the first surface and is bonded to the cooler by the bonding material; A second conductor pattern is disposed on the second surface; A semiconductor element, wherein the semiconductor element is electrically connected to the second conductor pattern; as well as A sealing material that covers the insulating layer, the second conductor pattern, and the semiconductor element.

5. The semiconductor device according to claim 4, characterized in that, The groove has: The first groove portion, which is part of the aforementioned portion; and A third groove, which, when viewed along the first direction, is located on the opposite side of the first groove relative to the bonding material. In the direction from the first groove toward the third groove, the distance between the first groove and the third groove is longer than the length of the first conductor pattern.

6. The semiconductor device according to claim 4 or 5, characterized in that, The insulating layer is made of ceramic.

7. The semiconductor device according to any one of claims 4 to 6, characterized in that, The coefficient of linear expansion of the sealing material is less than that of the cooler.

8. The semiconductor device according to any one of claims 1 to 7, characterized in that, When viewed along the first direction, the groove surrounds the bonding material.

9. The semiconductor device according to any one of claims 1 to 8, characterized in that, The cooler has a plate portion that forms the first main surface. The plate portion has a second main surface located on the opposite side of the first main surface. The depth of the groove in the thickness direction from the first main surface toward the second main surface is greater than the width of the groove in the direction perpendicular to the direction in which the groove extends when viewed along the first direction.

10. The semiconductor device according to any one of claims 1 to 8, characterized in that, The cooler has a plate portion that forms the first main surface. The plate portion has a second main surface located on the opposite side of the first main surface. In the thickness direction from the first main surface toward the second main surface, the depth of the groove is less than half the thickness of the plate portion.

11. The semiconductor device according to claim 10, characterized in that, In the thickness direction, the thickness of the plate portion is 2 mm or more.

12. The semiconductor device according to any one of claims 1 to 11, characterized in that, The fastened area has four first parts that are separated from each other. When viewed along the first direction, the groove is located on the inside of the quadrilateral formed by connecting the four first parts.

13. The semiconductor device according to claim 12, characterized in that, The fastened area has one or more second parts that are different from the four first parts. When viewed along the first direction, one or more second portions are disposed on the outer edge of the quadrilateral or on the inner side of the quadrilateral.

14. The semiconductor device according to any one of claims 1 to 8, characterized in that, The cooler has: A plate portion, the plate portion constituting the first main surface, and having a second main surface located on the opposite side of the first main surface; and Multiple heat dissipation sections connected to the plate portion on the second main surface. The plate portion has a first plate member located between the bottom surface of the portion of the groove and the second main surface. At least one of the plurality of heat dissipation sections is connected to the first plate component.

15. The semiconductor device according to claim 2, characterized in that, The cooler has: A plate portion, the plate portion constituting the first main surface, and having a second main surface located on the opposite side of the first main surface; and Multiple heat dissipation sections connected to the plate portion on the second main surface. The plate portion has a second plate member, which is located between the bottom surface of the second groove portion and the second main surface. At least one of the plurality of heat dissipation sections is connected to the second plate component.

16. The semiconductor device according to any one of claims 1 to 8, characterized in that, The cooler has a first non-bonding region that inhibits the wetting and spreading of the materials constituting the bonding material. When viewed along the first direction, the first non-jointed area is located between the groove and the joining material.

17. The semiconductor device according to claim 16, characterized in that, The cooler has: A plate portion, the plate portion forming the first main surface, and having a second main surface located on the opposite side of the first main surface; Multiple heat dissipation sections are connected to the plate portion on the second main surface; as well as A plating layer that covers at least a portion of the plate portion and the plurality of heat dissipation portions.

18. The semiconductor device according to claim 16 or 17, characterized in that, The cooler has a second non-bonding region that inhibits the wetting and spreading of the materials constituting the bonding material. The second non-jointed area covers the bottom surface of the groove and the side surface of the groove, respectively.

19. The semiconductor device according to any one of claims 4 to 7, characterized in that, The sealing material has the following characteristics: The main body portion is located relative to the contact surface between the first conductor pattern and the bonding material in a direction from the bonding material toward the first conductor pattern; as well as A protrusion, which is connected to the main body and extends in a direction from the main body toward the cooler.

20. The semiconductor device according to any one of claims 1 to 19, characterized in that, The groove has a fourth groove portion that is different from the aforementioned portion. When viewed along the first direction, the fourth groove is disposed between the fastening part and the portion of the groove.

21. The semiconductor device according to any one of claims 1 to 8, characterized in that, The cooler has: A plate portion, the plate portion constituting the first main surface, and having a second main surface located on the opposite side of the first main surface; and Multiple heat dissipation sections are connected to the plate portion on the second main surface. When viewed along the direction in which the plurality of heat dissipation parts extend, each of the plurality of heat dissipation parts has a polygonal shape.

22. The semiconductor device according to claim 21, characterized in that, When viewed along the direction in which the plurality of heat dissipation parts extend, each of the plurality of heat dissipation parts has a hexagonal shape.

23. The semiconductor device according to claim 21 or 22, characterized in that, The second main surface has: The outer peripheral area in contact with the sleeve; and A heat dissipation area, which is surrounded by the outer peripheral area, and is provided with the plurality of heat dissipation parts. When viewed along the direction in which the plurality of heat dissipation parts extend, the value obtained by dividing the total area of ​​the plurality of heat dissipation parts by the area of ​​the heat dissipation region is 0.2 or higher.

24. The semiconductor device according to any one of claims 4 to 7, characterized in that, The semiconductor element is a reverse-conduction insulated-gate bipolar transistor.

25. The semiconductor device according to any one of claims 4 to 7, characterized in that, The semiconductor element is made of silicon carbide.

26. A power conversion device, characterized in that, include: A main conversion circuit having a semiconductor device according to any one of claims 1 to 25, for converting and outputting input power; A driving circuit that outputs a driving signal to the semiconductor device to drive the semiconductor device; as well as A control circuit that outputs a control signal to the drive circuit to control the drive circuit.

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