Semiconductor device and method for manufacturing the same

Abstract

A power module (100) of a semiconductor device with high reliability is provided as a circuit for stably connecting a semiconductor element mounted on an insulating substrate with a warped main surface, and comprises an insulating substrate (10), a heat dissipation component (20) and an electrode plate (30). The insulating substrate (10) is equipped with an IGBT (41) and a diode (42). The heat dissipation component (20) is joined to the insulating substrate (10) by a first solder (51). The electrode plate (30) is arranged so as to overlap at least a portion of the semiconductor element. The main surface of the insulating substrate (10) is warped in such a way that the insulating substrate (10) becomes convex toward the heat dissipation component (20). The first solder (51) is thicker at the end than at the center when viewed from above. The semiconductor element is joined to the electrode plate (30) by a second solder (52).

Description

Technical Field

[0001] The present disclosure relates to a semiconductor device and a method for manufacturing the same. Background Art

[0002] So-called power modules, which are semiconductor devices, have become popular in all products from industrial equipment to home appliances and information terminals. Power modules installed in electric vehicles require high reliability. In addition, power modules for electric vehicles also need to have high operating temperatures and excellent efficiency. Therefore, power modules for electric vehicles are also required to be packaging methods that can be applied to silicon carbide semiconductors, which are likely to become mainstream in the future.

[0003] For example, in Japanese Patent Application Publication No. 2016-058563 (Patent Document 1), the thickness and linear expansion coefficient of the sealing resin are adjusted to be within an appropriate numerical range, thereby causing a downward convex warp in the insulating substrate to prevent air from being trapped in the heat dissipation grease portion between the heat dissipation component and the insulating substrate.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2016-058563 Summary of the invention

[0007] In a structure in which a warped and tilted insulating substrate is bonded to a base plate as disclosed in Japanese Patent Application Publication No. 2016-058563, the contact method of the wire tool changes when the wiring for forming a circuit is wire-bonded to the semiconductor element on the insulating substrate. That is, when multiple semiconductor elements are mounted on the insulating substrate, the inclination angle of the surface of the semiconductor element relative to the horizontal direction is different for each location of the multiple semiconductor elements. This results in the need to readjust the contact method of the wire tool during wire bonding for each of the multiple semiconductor elements. Therefore, for example, when the adjustment is insufficient, there is a possibility that the wire tool may damage the semiconductor element, making it difficult to wire bond the wiring with high reliability.

[0008] The present disclosure has been made in view of the above problems and has an object to provide a semiconductor device and a method for manufacturing the same which stably connect a circuit to a semiconductor element mounted on an insulating substrate whose main surface is warped and have high reliability.

[0009] The semiconductor device of this embodiment includes an insulating substrate, a heat dissipation component, and an electrode plate. The insulating substrate carries a semiconductor element. The heat dissipation component is bonded to the insulating substrate by a first solder. The electrode plate is arranged so as to overlap at least a portion of the semiconductor element. The main surface of the insulating substrate is warped in a convex shape toward the heat dissipation component side. The first solder is thicker at the end portion than at the center portion when viewed from above. The semiconductor element is bonded to the electrode plate by a second solder.

[0010] In the method for manufacturing a semiconductor device of the present embodiment, a heat dissipation component and an insulating substrate are joined by a first solder. A semiconductor element is joined to the insulating substrate. After the step of joining by the first solder and the step of joining the semiconductor element, an electrode plate overlapping at least a portion of the semiconductor element is joined to the semiconductor element by a second solder. The insulating substrate is joined to the heat dissipation component in a manner that the main surface is warped so as to be convex toward the heat dissipation component. The first solder is formed to be thicker at the end portion than at the center portion when viewed from above.

[0011] According to the present disclosure, it is possible to provide a semiconductor device and a method for manufacturing the same which can stably connect a circuit to a semiconductor element mounted on an insulating substrate whose main surface is warped and have high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic cross-sectional view showing the structure of a power module according to the first embodiment.

[0013] Figure 2 This is a schematic cross-sectional view showing a first modified example of the structure of the power module according to the first embodiment.

[0014] Figure 3 This is a schematic cross-sectional view showing a second modified example of the structure of the power module according to the first embodiment.

[0015] Figure 4 This is a schematic cross-sectional view showing a third modified example of the structure of the power module according to the first embodiment.

[0016] Figure 5 This is a schematic cross-sectional view showing a fourth modified example of the structure of the power module according to the first embodiment.

[0017] Figure 6 This is a schematic cross-sectional view showing a fifth modified example of the structure of the power module according to the first embodiment.

[0018] Figure 7 This is a diagram showing Embodiment 1. Figure 2 A schematic cross-sectional view of a first step of the method for manufacturing a power module.

[0019] Figure 8 This is a diagram showing Embodiment 1. Figure 2 A schematic cross-sectional view of a second step of the method for manufacturing a power module.

[0020] Fig. 9 This is a diagram showing Embodiment 1. Figure 2 A schematic cross-sectional view of a third step of the method for manufacturing a power module.

[0021] Fig.10 This is a diagram showing Embodiment 1. Figure 2 A schematic cross-sectional view of a fourth step of the method for manufacturing a power module.

[0022] Fig.11 This is a diagram showing Embodiment 1. Figure 1 A schematic cross-sectional view of a first step of the method for manufacturing a power module.

[0023] Fig.12 This is a diagram showing Embodiment 1. Figure 1 A schematic cross-sectional view of a second step of the method for manufacturing a power module.

[0024] Fig.13 This is a diagram showing Embodiment 1. Figure 1 A schematic cross-sectional view of a third step of the method for manufacturing a power module.

[0025] Fig.14 This is a schematic cross-sectional view showing the structure of a power module according to the second embodiment.

[0026] Fig.15 This is a schematic cross-sectional view showing the structure of a power module according to the third embodiment.

[0027] Fig.16 This is a schematic cross-sectional view showing a first step of a method for manufacturing a power module according to the third embodiment.

[0028] Fig.17 This is a schematic cross-sectional view showing a second step of the method for manufacturing a power module according to the third embodiment.

[0029] Fig.18 This is a schematic cross-sectional view showing a third step of the method for manufacturing a power module according to the third embodiment.

[0030] Fig.19 This is a schematic cross-sectional view showing a fourth step of the method for manufacturing a power module according to the third embodiment.

[0031] Fig. 20 This is a schematic cross-sectional view showing the structure of a power module according to the fourth embodiment.

[0032] Fig.21This is a schematic cross-sectional view showing a first step of a method for manufacturing a power module according to the fourth embodiment.

[0033] Fig. 22 This is a schematic cross-sectional view showing a second step of the method for manufacturing a power module according to the fourth embodiment.

[0034] Fig.23 This is a schematic cross-sectional view showing the structure of a power module according to the fifth embodiment.

[0035] Fig.24 This is a schematic cross-sectional view showing the structure of a power module according to the sixth embodiment.

[0036] Fig.25 This is a schematic cross-sectional view showing the structure of a power module according to the seventh embodiment.

[0037] Fig.26 This is a graph showing the results of measuring the maximum length of a crack formed at the end of the first solder.

[0038] Fig. 27 This is an ultrasonic flaw detection image of the end of the first solder after the temperature cycle test of the first sample.

[0039] Fig.28 This is an ultrasonic flaw detection image of the end of the first solder after the temperature cycle test of the third sample.

[0040] (Explanation of symbols)

[0041] 10: insulating substrate; 10A: curved portion; 10B: non-curved portion; 11: base material; 11A: one surface; 11B: the other surface; 12, 13: conductor layer; 12a: other conductor layer; 20: heat dissipation component; 21: base plate; 21A: first heat dissipation component portion; 21B: second heat dissipation component portion; 21C: protrusion; 22: fin; 30: electrode plate; 30A, 30B, 30C, 30D: main body; 31, 73A: first part ; 32, 73B: Part 2; 33: End on the main terminal side; 34: End on the semiconductor element side; 41: IGBT; 42: Diode; 43: Control semiconductor element; 51: First solder; 52: Second solder; 53: Third solder; 59: Conductive material; 59a: Fourth solder; 60: Frame member; 71: Signal electrode; 72, 73: Main terminals; 73C: Part 3; 81: Bonding wire; 90, 91: Sealing material; 100: Power module. DETAILED DESCRIPTION

[0042] Hereinafter, a power module 100 as a semiconductor device according to the present embodiment will be described with reference to the drawings. For convenience of description, an X direction, a Y direction, and a Z direction will be introduced.

[0043] Implementation method 1.

[0044] Figure 1 2 is a schematic cross-sectional view showing the structure of a power module according to Embodiment 1. Figure 1 The power module 100 of the present embodiment mainly includes an insulating substrate 10 , a heat dissipating member 20 , and an electrode plate 30 .

[0045] The insulating substrate 10 includes a base material 11, a conductor layer 12, and a conductor layer 13. The base material 11 has, for example, a rectangular shape when viewed from above, and has a thickness along the Z direction. The base material 11 has a surface 11A on one side as a main surface on the upper side in the Z direction, and a surface 11B on the other side as a main surface on the opposite side, that is, on the lower side in the Z direction. The conductor layer 12 is a thin plate-shaped conductor material bonded to one or more thin plate-shaped conductor materials on the surface 11A on one side. The conductor layer 13 is a thin plate-shaped conductor material bonded to one or more thin plate-shaped conductor materials on the other side of the surface 11B.

[0046] The main surface of the insulating substrate 10 means the surface along the XY plane of the entire object in which the thin conductor layer 12 and the thin conductor layer 13 are bonded to the surface 11A on one side and the surface 11B on the other side. Therefore, the main surface of the insulating substrate 10 extends in a manner that is substantially the same as the surface 11A on one side and the surface 11B on the other side. Therefore, hereinafter, the main surface of the entire insulating substrate 10 and the surface 11A on one side and the surface 11B on the other side are sometimes considered to be the same.

[0047] On the conductor layer 12 of the insulating substrate 10, an IGBT 41 (Integrated Gate Bipolar Transistor) and a diode 42 are mounted as semiconductor elements. These semiconductor elements are chip-shaped. Figure 1 As shown in FIG. 1 , the IGBT 41 as the second semiconductor element is arranged outside the diode 42 as the first semiconductor element in a plan view. However, the present invention is not limited thereto, and the IGBT 41 may be arranged inside the diode 42 in a plan view.

[0048] The heat dissipation component 20 includes a base plate 21 and fins 22. The base plate 21 is a plate-shaped component having a surface along the XY plane. The fins 22 are components extending from the bottom surface of the base plate 21, for example, in the Z direction, along the Z direction. A plurality of fins 22 extend from the bottom surface of the base plate 21 to the Z direction downward at intervals with respect to the X direction and the Y direction. In addition, the fins 22 may be integral with the base plate 21 or may be independent.

[0049] The uppermost surface of the base plate 21 of the heat dissipation component 20 in the Z direction is bonded to the main surface on the lower side of the insulating substrate 10 through the first solder 51. The insulating substrate 10 protrudes toward the heat dissipation component 20 side, that is, the lower side in the Z direction, and its main surface is warped in a convex shape that spans over the plurality of IGBTs 41 and diodes 42. That is, the insulating substrate 10 is bent in a manner such that the other surface 11B of the base material 11 becomes a convex shape when viewed from the outside, and the one surface 11A becomes a concave shape when viewed from the outside. The convex shape of the insulating substrate 10 is Figure 1 The entire X-direction forms a convex shape, and the plurality of IGBTs 41 and diodes 42 are all slightly inclined relative to the horizontal direction through the convex shape. Figure 1 The center of the X direction is Figure 1 The end of the X direction is shorter than the Z direction of the heat dissipation component 20. Therefore, the first solder 51 is thicker in the end in the Z direction than in the center when viewed from above. That is, the first solder 51 gradually becomes thicker from the center toward the end when viewed from above. In other words, the thickness of the first solder 51 increases monotonically from the center toward the end.

[0050] The first solder 51 bonds the entire surface of the conductor layer 13 on the other surface 11B. The entire surface here is not limited to the complete entire surface, and includes, for example, the case where the first solder layer 51 covers 95% or more of the surface area of ​​the conductor layer 13 .

[0051] The electrode plate 30 is arranged so as to overlap at least a portion of the IGBT 41 and the diode 42 when viewed from above. That is, the electrode plate 30 may overlap only a portion of the IGBT 41 when viewed from above, or may overlap the entire IGBT 41. The electrode plate 30 is arranged at a distance from the IGBT 41 and the diode 42 on the upper side of the IGBT 41 and the diode 42 in the Z direction. Figure 1 The electrode plate 30 is a planar shape such that its surface is along the XY plane. Figure 1 The electrode plate 30 has almost no warpage along the surface of the XY plane. The IGBT 41 and the diode 42 are bonded to the electrode plate 30 via the second solder 52. Here, the main electrodes not shown formed on the IGBT 41 and the diode 42 are bonded to the electrode plate 30 via the second solder 52. Thus, a circuit consisting of the IGBT 41, the diode 42 and the electrode plate 30 is formed. In addition, the IGBT 41 and the diode 42 are bonded to the conductor layer 12 of the insulating substrate 10 via the conductive material 59.

[0052] The power module 100 further includes a frame member 60 in the outer area when viewed from above. The frame member 60 is configured, for example, to be spaced apart from the insulating substrate 10 on which the IGBT 41 and the diode 42 are mounted in the X direction and the Y direction, and surrounds the insulating substrate 10. Furthermore, the frame member 60 is configured to surround an area such as a base plate 21 which is at least a part of the heat dissipation component 20 and (at least a part of) the main body 30A constituting the electrode plate 30. However, the base plate 21 may also be bonded to the frame member 60 with an adhesive not shown. In addition, a part of the main body 30A may also be in contact with the frame member 60 or embedded in the frame member 60. Thus, the electrode plate 30 is configured in the frame member 60 to be opposite to the insulating substrate 10 in the Z direction.

[0053] A signal electrode 71 is arranged inside the frame member 60. More specifically, the signal electrode 71 is arranged in such a manner that at least a portion is buried inside the frame member 60. The signal electrode 71 includes a portion exposed to the outside of the frame member 60, a portion buried inside the frame member 60, and a portion exposed from the frame member 60 on the inside of the frame member 60. In addition, the portion of the signal electrode 71 exposed from the frame member 60 on the inside of the frame member 60 is buried in the sealing material 90 as described later. In this specification, in the final product, the portion of the signal electrode 71 on the inside of the frame member 60 that is at least exposed from the frame member 60 is sometimes expressed as "exposed from the frame member 60". Among them, the portion of the signal electrode 71 on the inside of the frame member 60 that faces the upper side in the Z direction is electrically connected to the IGBT 41 and the diode 42 through the bonding wire 81.

[0054] The main body 30A of the electrode plate 30 includes a portion extending in the horizontal direction and facing the IGBT 41 and the diode 42 and a portion bent from the portion and extending in the Z direction. Figure 1 The rightmost area in the X direction extends along the Z direction. Figure 1 The portion of the rightmost region in the X direction extending in the Z direction and the portion extending in the horizontal direction by bending from the portion Figure 1 The rightmost area of ​​the main terminal 72 is the main terminal side end portion 33. On the other hand, the portion of the main body 30A extending in the horizontal direction Figure 1 The leftmost end in the X direction is the semiconductor element side end 34. The semiconductor element side end 34 is the end on the side opposite to the main terminal side end 33. Thus, the electrode plate 30 includes the main terminal side end 33 and the semiconductor element side end 34.

[0055] The main terminal side end portion 33 includes: a first portion 31 extending along the Z direction and exposed to the outside of the frame member 60; and a second portion 32 embedded in the frame member 60. The second portion 32 includes a portion where the main terminal 72 is bent. Thus, the electrode plate 30 electrically connects the inside and outside of the frame member 60 in a plan view.

[0056] Through the above, Figure 1 In the embodiment, the portion of the electrode plate 30 extending in the horizontal direction, that is, the XY plane, is integrated with the main terminal 72. Thus, the electrode plate 30 and the main terminal 72 are electrically connected.

[0057] Furthermore, the signal electrode 71 and the main body portion 30A of the electrode plate 30 including the main terminal 72 may be formed by dividing a single lead frame into two.

[0058] The region surrounded by the frame member 60 and the base plate 21 and where the insulating substrate 10 and the like are arranged is filled with the sealing material 90 . That is, the IGBT 41 and the diode 42 are sealed by the sealing material 90 as a sealing resin. The first solder 51 is in contact with the sealing material 90 .

[0059] Next, the material, size, etc. of each of the above components will be described.

[0060] The substrate 11 constituting the insulating substrate 10 is made of, for example, aluminum nitride. However, the substrate 11 may be formed of, for example, any material selected from aluminum oxide and silicon nitride instead of aluminum nitride. In this way, the substrate 11 is preferably formed of a ceramic material. However, without limitation thereto, the substrate 11 may also be formed of any resin selected from glass epoxy resin and metal-based resin. Alternatively, the substrate 11 may also be LTCC (Low Temperature Co-fired Ceramics) which is a so-called low temperature fired substrate. The size of the substrate 11 is, for example, 65 mm×65 mm×thickness 0.64 mm.

[0061] The conductor layers 12 and 13 are made of copper, for example. However, the conductor layers 12 and 13 may be made of nickel or nickel-plated aluminum instead of copper. The size of each of the conductor layers 12 divided into a plurality of parts is, for example, 30 mm × 61 mm × 0.4 mm. The size of the conductor layer 13 is, for example, 61 mm × 61 mm × 0.4 mm thick.

[0062] The base plate 21 and the fins 22 constituting the heat dissipation component 20 are made of, for example, aluminum. However, the heat dissipation component 20 is not limited thereto, and may be made of an aluminum alloy material such as A6063. Alternatively, the heat dissipation component 20 may be made of any material of copper and a copper alloy. A plating film of nickel or the like may be formed on the surface of each material constituting the heat dissipation component 20.

[0063] also, Figure 1 The heat dissipation component 20 has a base plate 21 and fins 22. However, when the cooling capacity of the base plate 21 alone is sufficient, the heat dissipation component 20 may be composed of only the base plate 21 without the fins 22. In addition, the base plate 21 of the heat dissipation component 20 may have a structure in which any of a fan for air cooling and a heat sink is built in, in which case, the fins 22 may be provided or not provided.

[0064] The main body portion 30A of the electrode plate 30 and the signal electrode 71 are preferably formed of a metal material such as copper.

[0065] The chips of IGBT 41 and diode 42 are made of silicon. In addition, any chip of a so-called IC (Integrated Circuit) chip and a chip equipped with a so-called MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) can be used instead of diode 42. The chip of IGBT 41 has a size of 13 mm × 13 mm × 0.2 mm in thickness, for example. The chip of diode 42 has a size of 13 mm × 10 mm × 0.2 mm in thickness, for example.

[0066] exist Figure 1 In the embodiment, the IGBT 41 and the diode 42 are configured in a so-called 2-in-1 module structure in which two pairs of IGBT 41 and the diode 42 are provided. However, the structure is not limited to such a structure, and a so-called 1-in-1 module structure in which, for example, one pair of IGBT 41 and the diode 42 is provided may be provided. Alternatively, a so-called 6-in-1 module structure in which, for example, six pairs of IGBT 41 and the diode 42 are provided may be provided. Alternatively, a discrete component having only one power semiconductor element may be used instead of the above structure.

[0067] The IGBT 41 has signal electrodes for gate signals and temperature sensors (not shown). Bonding wires are used to connect these signal electrodes to the frame member 60. Figure 1 As shown, generally, the IGBT 41 is arranged on the outer side in a plan view, which is a side close to the frame member 60 , and the diode 42 is arranged on the inner side.

[0068] Here, the first solder 51 has a small thickness at a position overlapping with the central portion of the insulating substrate 10 in a plan view, and in particular, the thermal resistance is reduced. From this point of view, it is considered preferable to arrange the IGBT 41 having a larger heat generation than the diode 42 at the central portion of the insulating substrate 10. However, even if the IGBT 41 is arranged as Figure 1As shown, the IGBT 41 is arranged on the outside when viewed from above. As long as the heat of the IGBT 41 is transferred to the insulating substrate 10, the temperature of the central part of the insulating substrate 10 becomes the highest due to thermal interference. Therefore, the IGBT 41 may be arranged further outside than the diode 42. It is preferred that the central part of the insulating substrate 10 where the temperature becomes the highest due to thermal interference is roughly aligned with the center, i.e., the vertex, of the convex shape formed by the insulating substrate 10 being warped downward.

[0069] The first solder 51 is Figure 1 The thickness of the central portion in the X direction is, for example, 0.2 mm. Figure 1 The thickness at the end portion in the X direction is, for example, 0.4 mm. Figure 1 The second solder 52 in the embodiment has a different thickness depending on the location where it is arranged. That is, the maximum thickness of the second solder 52 between the electrode plate 30 and the diode 42 is thicker than the maximum thickness of the second solder 52 between the electrode plate 30 and the IGBT 41 .

[0070] The first solder 51 and the second solder 52 are preferably composed of, for example, so-called 96Sn-3.5Ag-0.5Cu. That is, these solders are materials containing 96.5% by mass of tin, 3.5% by mass of silver, and 0.5% by mass of copper. However, this is not limited to this. The first solder 51 and the second solder 52 may also be materials containing 98.5% by mass of tin, 1% by mass of silver, and 0.5% by mass of copper. The first solder 51 and the second solder 52 may also be materials containing 96% by mass of tin, 3% by mass of antimony, and 1% by mass of silver.

[0071] The conductive material 59 may also be a solder material having the same composition as the first solder 51 and the second solder 52. However, the conductive material 59 is not limited to the solder material, and may also be composed of other types of conductive materials. For example, the conductive material 59 may also be a so-called Cu-Sn paste obtained by dispersing copper powder and isothermally solidifying it. The Cu-Sn paste can obtain high heat resistance. Alternatively, the conductive material 59 may also be a so-called nanosilver paste obtained by bonding nanosilver particles by low-temperature sintering.

[0072] The frame member 60 is formed of PPS (Poly Phenylene Sulfide) resin. However, the frame member 60 is not limited thereto, and may be formed of LCP (Liquid Crystal Polymer) resin, i.e., liquid crystal polymer resin. The outermost dimensions of the frame member 60 are, for example, 75 mm×75 mm×8 mm thick. The thickness of 8 mm is the dimension in the Z direction.

[0073] about Figure 1The frame member 60 is arranged such that the inner wall portion at the position where the main terminal 72 is embedded in the Z direction, i.e., the thickness direction, and the position where the base plate 21 is arranged are arranged further outward than the inner wall portion at other positions. The outer wall of the base plate 21 is at the same X direction (Y direction) position as a whole in the thickness direction. In this way, the frame member 60 can have a thinner side wall thickness at at least one of the positions where the main terminal 72 is embedded in the thickness direction and the positions where the base plate 21 is arranged than at other positions, i.e., the center portion in the thickness direction.

[0074] The bonding wire 81 is preferably a thin wire made of aluminum. However, the bonding wire 81 is not limited thereto, and may be any of a thin copper wire, a thin copper wire coated with aluminum, and a gold wire. The diameter of the cross section of the bonding wire 81 cut in a manner intersecting the direction in which it extends is preferably, for example, 0.15 mm.

[0075] The sealing material 90 is made of, for example, epoxy resin containing a silica filler, but the present invention is not limited thereto, and silicone rubber or the like may also be used as the sealing material 90 .

[0076] Figure 2 2 is a schematic cross-sectional view showing a modified example of the structure of the power module according to the first embodiment. Figure 2 The power module 100 of the modified example of this embodiment has Figure 1 The power module 100 has basically the same structure. Figure 2 Middle pair and Figure 1 The same components are denoted by the same reference numerals, and their functions and the like are not described repeatedly. This is also true for each power module described below unless otherwise specified.

[0077] However, in Figure 2 In the power module 100, the main surface of the portion of the electrode plate 30 that is opposite to the insulating substrate 10 in the main body portion 30A is bent along the convex shape of the insulating substrate 10 toward the heat dissipation component 20. That is, on the insulating substrate 10, the main surface of the electrode plate 30 is warped in a manner that is convex toward the heat dissipation component 20 in the same manner as the insulating substrate 10. The electrode plate 30 is bent in a manner that is convex when viewed from the outside and concave when viewed from the outside on the surface of the lower side, similarly to the insulating substrate 10. In this respect, Figure 2 The electrode plate 30 has almost no warping along the XY plane. Figure 1 The electrode plates 30 are different.

[0078] Figure 3 This is a schematic cross-sectional view showing a second modified example of the structure of the power module according to the first embodiment. Figure 4 2 is a schematic cross-sectional view showing a third modified example of the structure of the power module according to the first embodiment. Figure 3 , with Figure 1 The structure is basically the same as that of the first embodiment, but the conductor layer 12 on one surface 11A is formed thicker than the conductor layer 13 on the other surface 11B. Figure 1 Different. Similarly, refer to Figure 4 , with Figure 2 The structure is basically the same as that of the first embodiment, but the conductor layer 12 on one surface 11A is formed thicker than the conductor layer 13 on the other surface 11B. Figure 2 different.

[0079] If the conductor layer 12 on the one surface 11A is formed thicker than the conductor layer 13 on the other surface 11B, the insulating substrate 10 will be warped in a convex shape toward the heat dissipating member 20 .

[0080] In addition, consider a first region on one surface 11A to which the conductor layer 12 is not bonded, and a second region on the other surface 11B to which the conductor layer 13 is not bonded. If the area of ​​the first region is larger than that of the second region, the insulating substrate 10 warps in a convex shape toward the heat dissipation member 20. Furthermore, for example, if the conductor layer 12 on one surface 11A is formed thicker than the conductor layer 13 on the other surface 11B, the insulating substrate 10 warps in a convex shape toward the heat dissipation member 20 even if the first region and the second region have the same area.

[0081] Figure 5 This is a schematic cross-sectional view showing a fourth modified example of the structure of the power module according to the first embodiment. Figure 6 2 is a schematic cross-sectional view showing a fifth modified example of the structure of the power module according to the first embodiment. Figure 5 , with Figure 1 The structure is basically the same, but another conductor layer 12a is arranged between the conductor layer 12 on one surface 11A and the IGBT 41 and the diode 42. The other conductor layer 12a is joined to the conductor layer 12 by the fourth solder 59a so as to overlap with the conductor layer 12. Figure 6 , with Figure 2 Basically, the structure is the same, but another conductor layer 12a is arranged between the conductor layer 12 on one surface 11A and the IGBT 41 and the diode 42. The other conductor layer 12a is joined to the conductor layer 12 by the fourth solder 59a in an overlapping manner. In this aspect, Figure 5 , Figure 6 The other conductive layer 12a and the fourth solder 59a are not provided. Figure 1 , Figure 2 Different. Therefore, Figure 5 as well as Figure 6 and Figure 3 as well as Figure 4Similarly, the conductor layer on the surface 11A side of the substrate 11 functions as a portion that is substantially thicker than the conductor layer 13 on the surface 11B side of the substrate 11. Figure 5 as well as Figure 6 In, with Figure 3 as well as Figure 4 Likewise, the insulating substrate 10 is warped in a convex shape toward the heat dissipating member 20 .

[0082] Next, use Figure 7 to Figure 13 , a method for manufacturing the power module 100 of this embodiment is described. Figure 7 to Figure 10 In the description Figure 2 A method for manufacturing a power module 100 is provided.

[0083] Figure 7 This is a diagram showing Embodiment 1. Figure 2 A schematic cross-sectional view of a first step of a method for manufacturing a power module. Figure 7 First, the insulating substrate 10 , the heat dissipating member 20 , the semiconductor elements, namely the IGBT 41 and the diode 42 , the first solder 51 , and the conductive material 59 are prepared.

[0084] The insulating substrate 10 includes a substrate 11. One or more conductor layers 12 are bonded to a surface 11A on one side of the substrate 11, and one or more conductor layers 13 are bonded to a surface 11B on the other side opposite to the surface 11A on the one side. Consider a first area on the surface 11A on the one side where the conductor layer 12 is not bonded and a second area on the surface 11B on the other side where the conductor layer 13 is not bonded. The area difference between the first area and the second area is adjusted. Thus, the direction of the warping and the degree of the bending of the convex shape of the insulating substrate 10 after the components are bonded with solder are adjusted. Therefore, in Figure 7 In FIG. 1 , the insulating substrate 10 is illustrated in a non-bent state, but is actually slightly bent at this point in time.

[0085] The above components become Figure 1 as well as Figure 2 The structure of the power module 100 is positioned in the same manner as described above. That is, a plate-shaped first solder 51 is arranged between the heat dissipation component 20 and the conductor layer 13 of the insulating substrate 10. A plate-shaped conductive material 59 is arranged between the conductor layer 12 of the insulating substrate 10 and the IGBT 41 and the diode 42. These components are positioned in a manner to be arranged at positions to be arranged when they are joined to each other.

[0086] Figure 8 This is a diagram showing Embodiment 1. Figure 2 A schematic cross-sectional view of a second step of the method for manufacturing a power module. Figure 8 ,exist Figure 7In the state, the above-mentioned components are joined with the first solder 51 and the conductive material 59 using a reflow device. As a result, all the above-mentioned components are joined at the same time. That is, the heat dissipation component 20 and the insulating substrate 10 are joined by the first solder 51. The IGBT 41 and the diode 42 are joined to the insulating substrate 10. As described above, the bending direction and bending amount of the convex shape of the insulating substrate 10 after joining are determined by the conductor layers 12 and 13 of the insulating substrate 10. Therefore, the insulating substrate 10 is joined to the heat dissipation component 20 in such a way that the main surface is warped so as to become a convex shape toward the heat dissipation component 20 side. In order to form a convex shape of the insulating substrate 10, the first solder 51 is formed to be thicker at the end portion than at the center portion when viewed from above.

[0087] As described above, the heat dissipation component 20 and the insulating substrate 10 may be bonded together using the first solder 51, and the insulating substrate 10 and the IGBT 41 may be bonded together using the conductive material 59 at the same time. However, these two bondings may not be performed simultaneously but at different timings. However, in this case, it is preferred that the heat dissipation component 20 and the insulating substrate 10 are bonded together using the first solder 51 first, and then the insulating substrate 10 and the IGBT 41 are bonded together using the conductive material 59. Assuming that the insulating substrate 10 and the IGBT 41 are bonded together using the conductive material 59 first, and then the insulating substrate 10 is bonded to the heat dissipation component 20, there is a possibility that the conductive material 59 under the IGBT 41 will re-melt due to the heat during the bonding of the insulating substrate 10 and the heat dissipation component 20. If it re-melts, there is a possibility that the IGBT 41 and the like will be positionally displaced relative to the insulating substrate 10 due to the residual stress of the bonding wire (not shown) used in the circuit formation in the IGBT 41. From the viewpoint of preventing such a problem, it is preferred to bond in the above order.

[0088] As described above, after the step of bonding the heat dissipating member 20 and the insulating substrate 10 with the first solder 51 and the step of bonding the IGBT 41 and the diode 42 to the insulating substrate 10 with the conductive material 59 , the following step is performed: The second solder 52 and the frame member 60 are prepared.

[0089] The signal electrode 71 and the electrode plate 30 are partially embedded in the frame member 60. Figure 8 On the left side, the signal electrode 71 is insert-molded so as to be partially exposed from the frame member 60. Figure 8 On the right side, the second portion of the main terminal side end portion 33, which is a part of the main body portion 30A of the electrode plate 30, the bent portion, and the portion of the main body portion 30A along the XY plane are embedded. Figure 8The electrode plate 30 is insert-molded in such a manner as to be embedded in these areas. As a result, on the upper side of the frame member 60, the first portion 31 of the main terminal side end portion 33 of the main terminal 72 is exposed, and in the area surrounded by the frame member 60, the portion of the electrode plate 30 along the XY plane and the semiconductor element side end portion 34 are exposed.

[0090] A plate-shaped second solder 52 is disposed on the IGBT 41 and the diode 42. A portion of the electrode plate 30 along the XY plane is disposed on the second solder 52. Figure 2 When the main surface of the electrode plate 30 shown is set to be warped in a manner along the convex shape of the insulating substrate 10, it is preferable to bend the electrode plate 30 in advance by a generally known method. Alternatively, it is also possible to purchase an already bent electrode plate 30. Thus, the second solder 52, the electrode plate 30, and the frame member 60 are set to be positioned in a manner to be arranged at the positions where they should be arranged when they are joined to each other.

[0091] Fig. 9 This is a diagram showing Embodiment 1. Figure 2 A schematic cross-sectional view of a third step of the method for manufacturing a power module. Fig. 9 The frame member 60 in which the second portion 32 of the main terminal side end portion 33 is embedded is arranged to be spaced apart from the insulating substrate 10 and surround it. The electrode plate 30 is heated in a reflow furnace, and the electrode plate 30 is bonded to the IGBT 41 and the diode 42 with the second solder 52. That is, the electrode plate 30 is bonded to the IGBT 41 and the diode 42 by the second solder 52 in a manner overlapping at least a portion of the IGBT 41 and the diode 42. In addition, in more detail, in this process, the main electrodes of the IGBT 41 and the diode 42 (not shown) are bonded to the portion of the electrode plate 30 extending along the XY plane by the second solder 52.

[0092] Furthermore, the base plate 21 of the heat dissipating member 20 and the frame member 60 are bonded together using an adhesive (not shown).

[0093] Fig.10 2 is a schematic cross-sectional view showing a fourth step of the method for manufacturing the power module according to the first embodiment. Fig.10 The portion of the signal electrode 71 exposed inside the frame member 60 is electrically connected to the main electrode (not shown) of the IGBT 21 through the bonding wire 81. Thereafter, a liquid sealing material 90 is injected into the area surrounded by the frame member 60 and the heat dissipation member 20. This is heated at 150° C. for 1.5 hours, for example. Thus, the sealing material 90 is hardened. Thus, the components surrounded by the frame member 60 are electrically insulated.

[0094] Next, use Figure 11 to Figure 13 ,illustrate Figure 1A method for manufacturing a power module 100 is provided. Fig.11 This is a diagram showing Embodiment 1. Figure 1 A schematic cross-sectional view of a first step of the method for manufacturing a power module. Fig.12 This is a diagram showing Embodiment 1. Figure 1 A schematic cross-sectional view of a second step of the method for manufacturing a power module. Fig.13 This is a diagram showing Embodiment 1. Figure 1 A schematic cross-sectional view of a third step of the method for manufacturing a power module. Figure 11 to Figure 13 , even in Figure 1 In the example in which the main body 30A of the electrode plate 30 shown in FIG. 1 is not warped, the manufacturing method is basically the same as that shown in FIG. Figure 7 to Figure 10 The main body 30A of the electrode plate 30 shown in FIG. 1 is similar to the example of a convex shape. Figure 7 Similarly, prepare and position the components. Fig.11 As shown, Figure 8 Basically the same process. However, if Fig.11 As shown in FIG. 1 , the main body 30A of the electrode plate 30 is almost not warped. Fig.11 As shown, from the viewpoint of bonding the flat electrode plate 30 and the semiconductor element, the thickness of the second solder 52 at the center is greater than the thickness of the second solder 52 at the end. Fig.12 As shown, Fig. 9 Basically the same process. Next, Fig.13 Similarly, Fig.10 Basically the same process.

[0095] In addition, Figure 7 to Figure 10 , Figure 11 to Figure 13 In the manufacturing method, it is also possible to Figure 3 as well as Figure 4 As shown in FIG. 1 , the conductor layer 12 on one surface 11A is formed thicker than the conductor layer 13 on the other surface 11B. Figure 7 to Figure 10 , Figure 11 to Figure 13 In the manufacturing method, it is also possible to Figure 5 as well as Figure 6 As shown, another conductor layer 12a is bonded between the conductor layer 12 on one surface 11A and the IGBT 41 and the diode 42 so as to overlap the conductor layer 12. Thus, the convex warping of the insulating substrate 10 is adjusted so as to be convexly warped toward the heat sink 20.

[0096] Next, the background and problems of the present embodiment will be discussed, and the effects of the present embodiment will be described.

[0097] There is a strong demand for vehicle-mounted power modules to be small and lightweight. Therefore, vehicle-mounted power modules need to be densely configured with semiconductor elements that can apply high voltage and high current. As a result, thermal interference between multiple semiconductor elements sometimes becomes a problem, so being able to efficiently dissipate heat to heat dissipation components becomes an important design requirement. In addition, the power module is mounted on transportation equipment, so from the perspective of stably implementing the transportation of passengers, etc., high reliability is required.

[0098] The base plate and fins constituting the heat dissipation component are often formed of copper or aluminum with high thermal conductivity. However, there is a large difference in the thermal expansion coefficient between copper and aluminum and the aluminum nitride constituting the base material of the insulating substrate and the silicon constituting the semiconductor element. The power modules for vehicle-mounted and electric railways generate a large amount of heat, so the heat dissipation component and the insulating substrate need to be joined by solder, which has better thermal conductivity than heat dissipation grease. Therefore, a large thermal stress is applied to the joint between the heat dissipation component and the insulating substrate, and there is a possibility that cracks will occur in the joint during long-term reliability evaluations such as temperature cycling.

[0099] In addition, when soldering the insulating substrate to the heat dissipation component, the insulating substrate may be unexpectedly warped or tilted relative to the horizontal direction. When wire bonding is performed on an insulating substrate or an IGBT etc. that has such a tilt, the contact method of the wire tool changes for each location where wire bonding is desired. Therefore, it is necessary to readjust the contact method of the wire tool for each of the plurality of semiconductor elements, that is, each time wire bonding is performed at different locations with different tilts. If this adjustment is insufficient, there is a possibility that the wire tool may damage the semiconductor element, making it difficult to wire bond the wiring with high reliability.

[0100] Therefore, the power module 100 as a semiconductor device of the present embodiment includes an insulating substrate 10, a heat dissipation component 20, and an electrode plate 30. The insulating substrate 10 carries an IGBT 41 and a diode 42 as semiconductor elements. The heat dissipation component 20 is joined to the insulating substrate 10 by a first solder 51. The electrode plate 30 is arranged so as to overlap at least a portion of the semiconductor element. The main surface of the insulating substrate 10 is warped in such a way that the insulating substrate 10 becomes a convex shape protruding toward the heat dissipation component 20 side and spans a plurality of semiconductor elements. The first solder 51 is thicker at the end portion than at the center portion when viewed from above. The semiconductor element is joined to the electrode plate 30 by a second solder 52.

[0101] The heat dissipating member 20 is bonded to the insulating substrate 10 by the first solder 51 having a higher thermal conductivity than heat dissipating grease, for example. Therefore, a large amount of heat generated by the semiconductor element is efficiently dissipated from the first solder 51 to the heat dissipating member 20 .

[0102] The main surface of the insulating substrate 10 is warped in such a manner that the insulating substrate 10 becomes a convex shape toward the heat dissipation component 20 side, and the first solder 51 is thicker at the end than in the central portion. Thus, firstly, it is possible to suppress the thermal stress generated in the joint where the insulating substrate 10 and the heat dissipation component 20 are joined by the first solder 51 from being concentrated on the end when viewed from above. The thermal strain of the end of the first solder 51 becomes larger when viewed from above, but the first solder 51 at the end becomes thicker due to the convex shape, so the thermal strain at the end can be reduced. Therefore, it is possible to improve long-term reliability such as temperature cycling, for example, suppress the occurrence of cracks in the first solder 51. In addition, secondly, in the central portion where the temperature becomes the highest due to thermal interference, the first solder 51 becomes thinner, thereby reducing the thermal resistance. Therefore, it is possible to efficiently dissipate heat from the first solder 51 to the heat dissipation component 20.

[0103] The semiconductor element is bonded to the electrode plate 30 by the second solder 52. Therefore, for example, adjustment of the contact method of the wire tool based on the tilt angle of the insulating substrate 10 and the semiconductor element from the horizontal direction, which may occur when the power module 100 is electrically connected to the outside due to direct wire bonding of the semiconductor element, is no longer necessary. Therefore, it is possible to suppress the wire tool from damaging the semiconductor element due to the adjustment of the contact method of the wire tool. Therefore, the reliability of the electrical connection between the semiconductor element tilted relative to the horizontal direction due to the warping of the insulating substrate 10 and the outside of the power module 100 is improved compared to the case where the electrical connection is made by a bonding wire.

[0104] In the power module 100, the insulating substrate 10 includes a base material 11. One or more conductor layers 12 and 13 are bonded to a surface 11A on one side of the base material 11 and to a surface 11B on the other side opposite to the surface 11A on the one side. The first solder 51 is bonded to the entire surface of the conductor layer 13 on the other side of the surface 11B. The first solder 51 gradually becomes thicker from the center portion toward the end portion when viewed from above. Such a structure can also be used, thereby obtaining the same effect as described above.

[0105] The power module 100 described above preferably further includes a frame member 60 that is disposed to surround the insulating substrate 10 with a gap therebetween.

[0106] In this embodiment, the semiconductor element and the electrode plate 30 are bonded by the second solder 52. Therefore, unlike bonding at room temperature by wire bonding, for example, the second solder 52 is heated and melted during bonding. With this heating, unintended warping may occur in the insulating substrate 10. Therefore, it is assumed that the insulating substrate 10 that has been greatly deformed as described above interferes with the frame member 60, and there is a possibility that stress is generated in the insulating substrate 10, and its corner is defective or cracked.

[0107] Therefore, as described above, the frame member 60 is arranged at a distance from the insulating substrate 10 and the semiconductor element. As a result, the insulating substrate 10 and the first solder 51 are covered with a sealing material 90 composed of an epoxy resin or the like containing a silica filler near the outer side when viewed from above. The difference in thermal expansion coefficient between the base material 11 of the insulating substrate 10 and the heat dissipation component 20 is large, and there is a possibility that cracks will occur in the first solder 51 when evaluating the temperature cycle of the first solder 51. However, since the sealing material 90 is interposed between the two, the difference in thermal expansion coefficient between the base material 11 and the sealing material 90 and between the heat dissipation component 20 and the sealing material 90 can be reduced as described above. Therefore, the possibility of cracks occurring in the first solder 51 during long-term reliability evaluation such as the temperature cycle of the first solder is reduced, and the reliability of the power module 100 is improved.

[0108] In the power module 100, the electrode plate 30 is arranged in the frame member 60 so as to face the insulating substrate 10. The main surface of the electrode plate 30 may be warped so that the electrode plate 30 follows the convex shape of the insulating substrate 10. Thus, the thickness of the second solder 52 that joins the electrode plate 30 and the semiconductor element is constant between the plurality of semiconductor elements. Therefore, the electrode plate 30 and the semiconductor element can be reliably and stably joined by the second solder 52.

[0109] In the power module 100, the semiconductor element includes a diode 42 as a first semiconductor element and an IGBT 41 as a second semiconductor element arranged in a region closer to the frame member than the first semiconductor element in a plan view. The maximum thickness of the second solder 52 between the electrode plate 30 and the first semiconductor element may be thicker than the maximum thickness of the second solder 52 between the electrode plate 30 and the second semiconductor element. For example, when the main surface of the electrode plate 30 is not warped in a manner that the electrode plate 30 follows the convex shape of the insulating substrate 10, and has a planar main surface that is not curved along the XY plane, etc., such a mode is achieved.

[0110] That is, for example, when the temperature of the second semiconductor element is higher than that of the first semiconductor element, the second solder 52 in contact with the second semiconductor element is thinner than the second solder 52 in contact with the first semiconductor element. This can further reduce the overall thermal resistance from the semiconductor element to the heat dissipation member 20.

[0111] In the power module 100, the electrode plate 30 includes a main terminal side end portion 33 as a main terminal 72 and a semiconductor element side end portion 34 as an end portion on the side opposite to the main terminal side end portion. The main terminal side end portion 33 includes a first portion 31 exposed to the outside of the frame member 60 and a second portion 32 embedded in the frame member. Such a structure is preferred. Thus, in the present embodiment, the electrode plate 30 and the main terminal 72 are integrated and electrically connected. Therefore, the electrical connection structure between the semiconductor element and the outside of the power module 100 can be further simplified.

[0112] The power module 100 is further provided with a sealing material 90 as a sealing resin for sealing the semiconductor element. The first solder 51 is in contact with the sealing material 90. Thus, as described above, the insulating substrate 10 and the first solder 51 are covered with the sealing material 90 composed of epoxy resin or the like containing a silica filler near the outer side when viewed from above. The difference in thermal expansion coefficient between the base material 11 of the insulating substrate 10 and the heat dissipation component 20 is large, and there is a possibility that cracks will occur in the first solder 51 when evaluating the temperature cycle of the first solder 51. However, since the sealing material 90 is interposed between the two, the difference in thermal expansion coefficient between the base material 11 and the sealing material 90 and between the heat dissipation component 20 and the sealing material 90 can be reduced as compared with the above. Therefore, the possibility of cracks occurring in the first solder 51 during the long-term reliability evaluation such as the temperature cycle of the first solder is reduced, and the reliability of the power module 100 is improved.

[0113] In the manufacturing method of the semiconductor device, i.e., the power module 100, of the present embodiment, the heat dissipation component 20 and the insulating substrate 10 are joined by the first solder 51. The IGBT 41 and the diode 42 as semiconductor elements are joined to the insulating substrate 10. After the step of joining by the first solder 51 and the step of joining the semiconductor element, the electrode plate 30 overlapping at least a portion on the semiconductor element is joined to the semiconductor element by the second solder 52. The insulating substrate 10 is joined to the heat dissipation component 20 in a manner such that the main surface is warped so as to be convex toward the heat dissipation component 20. The first solder 51 is formed to be thicker at the end portion than at the center portion when viewed from above. The effect it has is the same as the effect of the basic structure of the power module 100 described above, so its description is not repeated.

[0114] In the manufacturing method of the power module 100, the insulating substrate 10 includes a substrate 11. One or more conductor layers 12 and 13 are bonded to a surface 11A on one side of the substrate 11 and to a surface 11B on the other side opposite to the surface 11A. The convex warping is adjusted by adjusting the area difference between the first region on the surface 11A on one side where the conductor layer 12 is not bonded and the second region on the surface 11B on the other side where the conductor layer 13 is not bonded. Thus, the direction and amount of the warping of the main surface of the insulating substrate 10 can be controlled.

[0115] In the method for manufacturing power module 100 , conductor layer 12 on one surface 11A may be formed thicker than conductor layer 13 on the other surface 11B to adjust the convex warping. In this way, insulating substrate 10 can be adjusted so as to warp convexly toward heat sink 20 .

[0116] In the manufacturing method of the power module 100, the convex warping can be adjusted by further comprising a step of bonding another conductor layer 12a between the conductor layer 12 on one surface 11A and the IGBT 41 and the diode 42 so as to overlap with the conductor layer 12. Thus, the insulating substrate 10 can be adjusted so as to be warped in a convex shape toward the heat sink 20.

[0117] Implementation method 2.

[0118] Fig.14 2 is a schematic cross-sectional view showing the structure of a power module according to Embodiment 2. Fig.14 In the power module 100 of the present embodiment, the base plate 21 of the heat dissipation component 20 includes a first heat dissipation component portion 21A and a second heat dissipation component portion 21B. The first heat dissipation component portion 21A is a plate-shaped portion having a surface along the XY plane, similarly to the base plate 21 of the first embodiment. Therefore, the uppermost surface of the first heat dissipation component portion 21A in the Z direction is bonded to the main surface of the lower side of the insulating substrate 10 through the first solder 51. The second heat dissipation component portion 21B is arranged on the outer side of the first heat dissipation component portion 21A when viewed from above in a manner that is integrated with the first heat dissipation component portion 21A. The second heat dissipation component portion 21B is arranged to surround the first heat dissipation component portion 21A and the first solder 51 thereon when viewed from above. The second heat dissipation component portion 21B is arranged at a position whose coordinates in the Z direction are equal to those of the first heat dissipation component portion 21A and in an area extending upward from this position in the Z direction. Therefore, the second heat dissipating member portion 21B is formed thicker than the first heat dissipating member portion 21A so as to extend upward (toward the insulating substrate 10 ) in the Z direction. The frame member 60 is mounted on the second heat dissipating member portion 21B formed thicker than the first heat dissipating member portion 21A.

[0119] Therefore, a concave portion is formed by the first heat dissipation component portion 21A and the second heat dissipation component portion 21B formed integrally on the outer side thereof. The concave portion accommodates the first solder 51 and the insulating substrate 10. In the above aspects, Fig.14 The base plate 21 is as Figure 1 The portion shown has only the flat plate component and no recess is formed. Figure 1 The base plate 21 is different.

[0120] Next, the effects of this embodiment will be described. In addition to the same effects as those of the basic structure of Embodiment 1, this embodiment also has the following effects. This is the same for each of the following embodiments unless otherwise specified.

[0121] The power module 100 of the present embodiment includes a first heat dissipation component portion 21A and a second heat dissipation component portion 21B. The first heat dissipation component portion 21A is bonded to the insulating substrate 10 via the first solder 51. The second heat dissipation component portion 21B surrounds the first heat dissipation component portion 21A and the first solder 51 outside the first heat dissipation component portion 21A in a plan view, and is provided with a frame member 60. In the heat dissipation component 20, a recess formed by the first heat dissipation component portion 21A and the second heat dissipation component portion 21B accommodates the first solder 51 and the insulating substrate 10.

[0122] Thus, compared to the first embodiment, the rigidity of the entire base plate 21 is not reduced, and the first solder 51 can be made thinner to reduce its rigidity. Therefore, it is possible to suppress the occurrence of cracks in the first solder 51 during long-term reliability evaluations such as temperature cycling. In addition, the thickness of the frame member 60 thereon is reduced by the amount of the second heat dissipation member portion 21B. The PPS resin constituting the frame member 60 lacks adhesion to the sealing material 90. Therefore, by reducing the size of the frame member 60 in the Z direction, the area of ​​the bonding interface between the sealing material 90 and the frame member 60 can be reduced, and the peeling between the two can be suppressed.

[0123] Implementation method 3.

[0124] Fig.15 2 is a schematic cross-sectional view showing the structure of a power module according to Embodiment 3. Fig.15 In the power module 100 of the present embodiment, the electrode plate 30 does not have an area corresponding to the main terminal 72, and the frame member 60 on the right side of the figure further has a main terminal 73. The main terminal 73 is equivalent to the main terminal 72 of the first embodiment. However, the main terminal 73 is not a part of the main body 30A of the electrode plate 30 that is integrated with the electrode plate 30. The main terminal 73 is a component independent of the electrode plate 30.

[0125] The main terminal 73 includes a first portion 73A, a second portion 73B, and a third portion 73C. The first portion 73A is Figure 1 The first portion 73A is a portion corresponding to the first portion 31 of the main terminal 72. The first portion 73A is a portion that is exposed to the outside of the frame member 60 in a manner extending in the Z direction. The second portion 73B is Figure 1 The second portion 73B is a portion embedded in the frame member 60 and includes Fig.15The third portion 73C is a portion of the main terminal 73 that is bent in the middle. The third portion 73C is a portion of the main terminal 73 that is connected to the main terminal side end portion 33 of the electrode plate 30 on the inner side of the frame member 60 and serves as a connection portion. In addition, the third portion 73C that serves as a connection portion is exposed from the frame member 60 on the inner side of the frame member 60, but is buried in the sealing material 90. Even if it is assumed that it is buried in the sealing material 90 in the final product, it is at least exposed from the frame member 60, so in this specification, such a third portion 73C is sometimes expressed as "exposed from the frame member 60".

[0126] As described above, the main terminal 73 is configured as a separate component from the electrode plate 30. Therefore, the main body 30B of the electrode plate 30 does not have a main terminal, but only has a portion extending in the horizontal direction along the XY plane. Fig.15 The main body 30B of the electrode plate 30 includes a main terminal side end 33 and a semiconductor element side end 34. The main terminal side end 33 is Fig.15 The main terminal side end portion 33 is connected to the main terminal 73. The semiconductor element side end portion 34 is the side opposite to the main terminal side end portion 33, that is, Fig.15 The area of ​​the leftmost end portion of the main body portion 30B in the X direction.

[0127] exist Fig.15 In the embodiment, the main terminal side end portion 33 of the electrode plate 30 and the third portion 73C as the connection portion of the main terminal 73 are joined by the third solder 53. That is, the portion of the main terminal side end portion 33 facing the lower side in the Z direction and the portion of the third portion 73C facing the upper side in the Z direction are joined by the third solder 53. Therefore, the main terminal side end portion 33 is preferably Fig.15 The rightmost area in the X direction extends to a position overlapping with the third portion 73C of the main terminal 73 when viewed from above. The material of the main body 30B of the electrode plate 30 and the main terminal 73 of the present embodiment is the same as the material of the main body 30A of the electrode plate 30 and the signal electrode 71 in the first embodiment, which is a metal material such as copper.

[0128] Furthermore, the signal electrode 71, the main terminal 73, and the main body 30B of the electrode plate 30 may be formed by dividing a single lead frame into three parts. The main body 30B is preferably formed of a metal material such as copper.

[0129] In this embodiment, the electrode plate 30 and the main terminal 73 are separate components, and both are electrically connected by the third solder 53. In this respect, this embodiment is structurally different from Embodiments 1 and 2 in which the electrode plate 30 and the main terminal are integrated and directly connected.

[0130] Next, use Figure 16 to Figure 19 ,illustrate Fig.15The manufacturing method of the power module 100 shown in FIG. 1 is described using an example in which the electrode plate 30 is not pre-bent and the main surface is flat. Figure 7 to Figure 10 Likewise, in this embodiment, the electrode plate 30 that is bent in advance may be used. This is also the same in the following embodiments.

[0131] Fig.16 1 is a schematic cross-sectional view showing a first step of a method for manufacturing a power module according to Embodiment 3. Fig.16 First, conduct Figure 7 The same process is performed by reflowing the first solder 51 and the conductive material 59 to bond the Figure 7 After the bonding process of the components using the reflow device, the second solder 52 and the electrode plate 30 are prepared. Figure 8 This corresponds to a step of preparing the second solder 52 and the frame member 60 after the joining step in FIG.

[0132] exist Fig.16 In, prepare Fig.15 The electrode plate 30 shown here has no main terminals and thus no bent portion and is composed of a flat plate-shaped main body 30B. In addition, the second solder 52 is thicker in the center than at the ends from the viewpoint of bonding the flat plate-shaped electrode plate 30 and the semiconductor element.

[0133] Fig.17 2 is a schematic cross-sectional view showing a second step of the method for manufacturing a power module according to the third embodiment. Fig.17 ,and Fig. 9 In the same manner as in the step of , the electrode plate 30 is bonded to the IGBT 41 and the diode 42 by the second solder 52 so as to overlap at least a portion of the IGBT 41 and the diode 42 .

[0134] Fig.18 2 is a schematic cross-sectional view showing a third step of the method for manufacturing a power module according to the third embodiment. Fig.18 , prepare the frame member 60. Fig.18 On the left side, the signal electrode 71 is insert-molded so as to be partially exposed from the frame member 60. Fig.18 On the right side, a main terminal 73 is embedded by insert molding so as to be partially exposed from the frame member 60 .

[0135] Fig.19 2 is a schematic cross-sectional view showing a fourth step of the method for manufacturing a power module according to the third embodiment. Fig.19 ,exist Fig.18In the state of being heated in a reflow furnace, the electrode plate 30 and the third portion 73C of the main terminal 73 are joined by the third solder 53. Fig. 9 The bonding of the base plate 21 and the frame member 60 using an adhesive and Fig.10 The same process forms Fig.15 A power module 100 is provided.

[0136] Next, the effects of the present embodiment will be described. The power module 100 of the present embodiment further includes a main terminal 73. The main terminal 73 includes a third portion 73C as a connection portion that is exposed from the frame member 60 on the inner side of the frame member 60. The electrode plate 30 includes a main terminal side end portion 33 connected to the main terminal 73 and a semiconductor element side end portion 34 that is an end portion on the opposite side to the main terminal side end portion 33. The main terminal side end portion 33 of the electrode plate 30 and the third portion 73C are joined by a third solder 53.

[0137] In the manufacturing method of the power module 100 of the present embodiment, a frame member 60 is prepared which is arranged to surround the insulating substrate 10 at a distance from the insulating substrate 10 and has the main terminal 73 embedded therein. After the step of bonding the electrode plate 30 to the semiconductor element using the second solder 52, the electrode plate 30 and the main terminal 73 are bonded using the third solder 53.

[0138] For example Figure 15 to Figure 19 As shown, there is a case where the difference between the thickness of the second solder 52 in the center portion when viewed from above and the thickness of the second solder 52 in the end portion when viewed from above becomes larger. In this case, even if it is assumed that the insulating substrate 10 is not intentionally deformed by large warping or the like, it is possible to suppress undesirable phenomena such as partial cracking of the second solder 52. After the electrode plate 30 and the semiconductor element are joined with the second solder 52, the main terminal 73 and the electrode plate 30 are joined with the third solder 53. Therefore, by adjusting the supply amount of the third solder 53, etc., it is possible to absorb the stress applied to the second solder 52 due to the deformation of the electrode plate 30 in the joint portion with the third solder 53.

[0139] Implementation method 4.

[0140] Fig. 20 2 is a schematic cross-sectional view showing the structure of a power module according to Embodiment 4. Fig. 20 The power module 100 of this embodiment has the same Fig.15 The power module 100 of the embodiment of the present invention has a substantially similar structure. The main body 30C of the electrode plate 30 has no main terminals and only a portion extending in the horizontal direction along the XY plane, similarly to the main body 30B. Fig. 20 In, with Fig.15 The same components are given the same reference numerals, and their functions and the like are not described repeatedly. Fig. 20 In the embodiment, the main terminal side end portion 33 of the electrode plate 30 and the third portion 73C as the connection portion of the main terminal 73 are bonded by a bonding wire 82. The bonding wire 82 extends in the direction along the X direction. Therefore, the main body portion 30C of the electrode plate 30 may not extend to the rightmost region of the main terminal side end portion 33 in the X direction. Fig.15 The position shown overlaps with the third portion 73C where the main terminal 73 is exposed from the frame member 60 and connected to the electrode plate 30 in a plan view. Fig. 20 In the embodiment, the main terminal side end portion 33 extends to the position adjacent to the main terminal side end portion 33 when viewed from above. Fig. 20 The area overlapping the IGBT 41 on the right side of the bonding wire 82 does not extend further to the right. In addition, the material and size of the bonding wire 82 are preferably the same as those of the bonding wire 81. The material of the main body 30C is preferably a metal material such as copper, similar to the main body 30A and 30B.

[0141] In this embodiment, the electrode plate 30 and the main terminal 73 are independent components and are electrically connected via a bonding wire 82. In this respect, this embodiment is structurally different from Embodiments 1 and 2 in which the electrode plate 30 and the main terminal are integrated and directly connected.

[0142] Next, use Figure 21-22 ,illustrate Fig. 20 The manufacturing method of the power module 100 is shown. Fig.21 1 is a schematic cross-sectional view showing a first step of a method for manufacturing a power module according to a fourth embodiment. Fig.21 First, perform the same Figure 16 to Figure 18 The rightmost region in the X direction of the main terminal side end portion 33 of the flat plate-shaped main body portion 30C closest to the main terminal 73 may be arranged further to the left than in the third embodiment.

[0143] Fig. 22 2 is a schematic cross-sectional view showing a second step of the method for manufacturing a power module according to the fourth embodiment. Fig. 22 ,exist Fig.21 In the state of the electrode plate 30 and the third portion 73C of the main terminal 73 are bonded by a wire bonding process, that is, by a bonding wire 82. The subsequent process is the same as that of the third embodiment. Fig. 20 A power module 100 is provided.

[0144] Next, the effects of the embodiment will be described. The power module 100 of the present embodiment further includes a main terminal 73. The main terminal 73 includes a third portion 73C as a connection portion that is exposed from the frame member on the inner side of the frame member 60. The electrode plate 30 includes a main terminal side end portion 33 connected to the main terminal 73 and a semiconductor element side end portion 34 that is an end portion on the opposite side to the main terminal side end portion 33. The main terminal side end portion 33 of the electrode plate 30 and the third portion 73C are bonded by a bonding wire 82.

[0145] In the manufacturing method of the power module 100 of the present embodiment, a frame member 60 is prepared which is arranged to surround the insulating substrate 10 at a distance from the insulating substrate 10 and has the main terminal 73 embedded therein. After the step of bonding the electrode plate 30 to the semiconductor element using the second solder 52, the electrode plate 30 and the main terminal 73 are bonded by a wire bonding step.

[0146] As described in the background and topics of the first embodiment, when wire bonding is performed directly on an insulating substrate and a semiconductor element such as an IGBT that is tilted to form a circuit, problems such as the wire tool damaging the semiconductor element may occur. However, as described in the present embodiment, an electrode plate 30 is interposed between the semiconductor element and the main terminal 73, and the electrode plate 30 and the main terminal 73 are joined by wire bonding. As a result, the number of bonding wires 81 and 82 can be reduced compared to the case of direct wire bonding on the semiconductor element. In addition, the possibility of the wire tool damaging the semiconductor element due to the tilt of the surface of the semiconductor element accompanying the warping of the insulating substrate 10 can be reduced, thereby improving the reliability of the bonding wires 81 and 82.

[0147] Implementation method 5.

[0148] Fig.23 2 is a schematic cross-sectional view showing the structure of a power module according to Embodiment 5. Fig.23 In the power module 100 of the present embodiment, a protrusion 21C is formed on the heat dissipation component 20. Specifically, the base plate 21 of the heat dissipation component 20 is formed with the protrusion 21C, and the protrusion 21C has a vertex at a position overlapping with a region where the temperature of the other surface 11B side, which is the back side of the insulating substrate 10, becomes the highest when the semiconductor element is in operation when viewed from above. Fig.23 In the example, the temperature of the semiconductor element becomes the highest at the center portion when the insulating substrate 10 is viewed from above when the semiconductor element is in operation. That is, a protrusion 21C having a vertex is formed at a position of the base plate 21 overlapping with the center portion when the insulating substrate 10 is viewed from above. In addition, when carefully observed, the semiconductor element reaches the highest temperature during operation, but when the insulating substrate 10 is observed from the back side, the heat diffuses and the peak of the heat distribution is unclear, so the temperature of the center portion becomes the highest.

[0149] The protrusion 21C is formed on the uppermost surface of the base plate 21 in contact with the first solder 51. The uppermost surface of the base plate 21 is expanded in a convex shape toward the upper side in such a manner that the protrusion 21C places the uppermost surface of the base plate 21 at the top. Therefore, the base plate 21 has the largest thickness at the protrusion 21C. The top of the protrusion 21C is preferably thicker than the thinnest end of the base plate 21 by about 0.1 mm.

[0150] Thus, the first solder 51 in the region where the temperature becomes high can be made thinner, and the first solder 51 at the end can be made thicker. Therefore, the thermal resistance of the first solder 51 in the region where the temperature becomes high in the center becomes smaller, so the heat dissipation is improved. In addition, the thermal strain in the first solder 51 can be reduced at the end, and the occurrence of cracks in the first solder 51 can be suppressed.

[0151] Implementation method 6.

[0152] Fig.24 2 is a schematic cross-sectional view showing the structure of a power module according to Embodiment 6. Fig.24 In the power module 100 of the present embodiment, the insulating substrate 10 includes a bent portion 10A and a non-bent portion 10B. Similar to the other embodiments described above, the bent portion 10A is a portion where the main surface is warped in such a manner that the insulating substrate 10 becomes a convex shape toward the heat dissipation component 20 side. The non-bent portion 10B is a region where the main surface extends flatly in such a manner that the insulating substrate 10 is not warped like the bent portion 10A but is roughly along the XY plane. The bent portion 10A and the non-bent portion 10B are configured to be arranged in the horizontal direction. Therefore, in the present embodiment, only the bent portion 10A other than the non-bent portion 10B in the insulating substrate 10 is considered, and a convex central portion is formed in the central portion of the bent portion 10A when viewed from above. Preferably, the first solder 51 is thinnest at a position overlapping with the central portion of the bent portion 10A. However, in this embodiment, as in other embodiments, the first solder 51 may be thinnest at a position overlapping with the center portion of the entire insulating substrate 10 including the bent portion 10A and the non-bent portion 10B in a plan view, and may be thicker at the end portions.

[0153] In the same manner as in the other embodiments, the IGBT 41 and the diode 42 are mounted on the conductor layer 12 in the curved portion 10A. On the other hand, the control semiconductor element 43 is mounted on the conductor layer 12 in the non-curved portion 10B. The control semiconductor element 43 is generally an IC (Integrated Circuit) in which a program for driving the IGBT 41 and the diode 42 is written, i.e., a so-called microcomputer.

[0154] exist Fig.24In the figure, the conductor layer 12 is shown to be connected from the bent portion 10A to the non-bent portion 10B. However, the conductor layer 12 may be divided between the bent portion 10A and the non-bent portion 10B to become an independent component.

[0155] The power module 100 may also have such a structure. The control semiconductor element 43 generates almost no heat. Therefore, the first solder 51 at the position overlapping the control semiconductor element 43 may also be formed to be as thick as the end of the first solder 51 in the entirety. That is, the thickness of the first solder 51 may also be substantially the same in the entirety of the non-bending portion 10B. Thus, the surface of the control semiconductor element 43 in the non-bending portion 10B is arranged along the horizontal direction, that is, with almost no inclination. Therefore, the control semiconductor element 43 can reduce the possibility of damage to the control semiconductor element caused by inclination during wire bonding thereon.

[0156] Implementation method 7.

[0157] Fig.25 2 is a schematic cross-sectional view showing the structure of a power module according to Embodiment 7. Fig.25 The power module 100 may also be a structure without the frame member 60. In the present embodiment, the sealing material 91 of the power module 100 seals the other components in such a way that at least a portion of the bottom surface of the base plate 21 and the entire fin 22 are exposed. Since there is no frame member 60, the sealing material 91 forms the outermost surface of the power module 100.

[0158] exist Fig.25 In the embodiment, the main body 30D of the electrode plate 30 is configured as an independent component independent of the main terminal 73 and the signal electrode 71. However, the main body 30D only has a portion extending in the horizontal direction along the XY plane. Fig.25 As shown, in this embodiment, the signal electrode 71 and the main terminal 73 may be arranged on the same plane along the same plane as the XY plane in which the main body 30D extends. The main body 30D and the signal electrode 71 are connected by the bonding wire 81 as in other embodiments. The main body 30D and the main terminal 73 may be connected by any means such as any of the third solder 53 and the bonding wire 82.

[0159] In addition, the signal electrode 71, the main terminal 73, and the main body 30D of the electrode plate 30 may also be a structure in which a single lead frame is divided into three. Alternatively, the main body 30D and the main terminal 73 may be integrated as described in Embodiment 1. Therefore, the main body 30D is preferably formed of a metal material such as copper.

[0160] The sealing material 91 is preferably an epoxy resin filled with silica formed by transfer molding. Specifically, in the transfer molding process, for example, the following process is performed. In the mold, a plurality of layers are stacked in a manner including the main body 30D and at least a portion of the signal electrode 71. Fig.25 The structure of each component such as the base plate 21, the insulating substrate 10, the semiconductor element, etc. is fixed in a clamping manner. At this time, the mold is heated to 170°C. The mold is a machined product of stainless steel. Next, the solid sheet of resin for the transfer mold is heated and pressurized and poured into the mold. By heating the entire inside of the mold at 170°C for 1 minute, the resin is hardened. Thereafter, the entirety including the sealing material 91 as the hardened resin is removed from the mold. The entirety removed from the mold is heated at 170°C in an oven for 2 hours. By the above, a film having Fig.25 The power module 100 is a power module 100 in the form of a sealing material 91. The effects of this embodiment are the same as those of the first embodiment, and thus the description thereof will not be repeated.

[0161] Example 1

[0162] The long-term reliability evaluation of the temperature cycle of the first solder 51 bonding the insulating substrate 10 and the heat dissipating member 20 described above was performed. Specifically, one sample of each of the following three types of power modules was prepared.

[0163] The first sample has the above Figure 1 That is, the first sample is warped in such a way that the main surface of the insulating substrate 10 becomes convex toward the heat dissipation component 20. In the first sample, Figure 1 The thickness of the first solder 51 is 0.2 mm in the center and 0.4 mm in the end. That is, similarly to the first embodiment, the thickness of the first solder 51 is larger at the end than at the center. The second sample has basically the same structure as the first sample, but the thickness of the first solder 51 is the same at the center and at the end. In the second sample, the thickness of the first solder 51 is 0.3 mm in the center and at the end. The third sample has basically the same structure as the first sample, but the thickness of the first solder 51 is 0.3 mm in the center and at the end, and is 0.2 mm. That is, the thickness of the first solder 51 is smaller at the end than at the center, contrary to the first embodiment.

[0164] The three types of samples were left in an atmosphere of 125° C. and an atmosphere of -40° C. for 30 minutes each. A temperature cycle test was performed in which the same treatment was repeated multiple times as one cycle. After that, the first solder 51 was subjected to ultrasonic flaw detection photography.

[0165] Fig.26 This is a graph showing the results of measuring the maximum length of a crack formed at the end of the first solder. Fig.26 The horizontal axis represents the number of times the above-mentioned one cycle is performed for each sample. Fig.26 The vertical axis represents the maximum length of the crack at the end of the first solder 51 after the above-mentioned one cycle is repeated multiple times. Fig.26 The black circle in the figure represents the first sample. Fig.26 The white triangle in the figure represents the second sample. Fig.26 The white rectangle in the middle represents the third sample.

[0166] Reference Fig.26 , the first sample had almost no cracks even after 1000 cycles. In contrast, the second sample had a crack of 10 mm from the end of the first solder 51 after 1000 cycles. The third sample had a crack of 22 mm from the end of the first solder 51 after 1000 cycles.

[0167] Fig. 27 This is an ultrasonic flaw detection image of the end of the first solder after the temperature cycle test of the first sample. Fig.28 This is an ultrasonic flaw detection image of the end of the first solder after the temperature cycle test of the third sample. Fig. 27 , the cracks in the first solder 51 of the first sample hardly extended before and after 1000 cycles of the temperature cycle test. Fig.28 In the third sample, before the temperature cycle test, the crack in the first solder 51 hardly extended, whereas after 1000 cycles, a crack having a length L in the figure was formed. From the above, it was confirmed that cracks can be suppressed by making the first solder thicker at the end than at the center when viewed from above.

[0168] The features described in the above-described embodiments (including the examples) may be appropriately combined and applied within the scope of technical non-contradiction. For example, in embodiments 5 and 6, the structure having the main body 30B, 30C and the main terminal 73 may be applied as in embodiments 3 and 4.

[0169] The embodiments disclosed this time should be considered as illustrative in all aspects and not restrictive. The scope of the present disclosure is indicated by the claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A semiconductor device comprising: Insulating substrate, carrying semiconductor components; a heat dissipation component joined to the insulating substrate via a first solder; and The electrode plate is arranged so as to overlap at least a portion of the semiconductor element. The main surface of the insulating substrate is warped so that the insulating substrate has a convex shape that protrudes toward the heat dissipating member and straddles the plurality of semiconductor elements. The first solder is thicker at the end portion than at the center portion when viewed from above, The semiconductor element is bonded to the electrode plate via a second solder. The semiconductor device further includes a frame member disposed so as to surround the insulating substrate at a distance from the insulating substrate. The semiconductor element includes a first semiconductor element and a second semiconductor element arranged in a region closer to the frame member than the first semiconductor element in a plan view. The maximum thickness of the second solder between the electrode plate and the first semiconductor element is thicker than the maximum thickness of the second solder between the electrode plate and the second semiconductor element. The heat dissipation component comprises: a first heat dissipation component portion joined to the insulating substrate via the first solder; as well as The second heat dissipation component surrounds the first heat dissipation component and the first solder on the outer side of the first heat dissipation component in a plan view and is provided with the frame member. In the heat dissipation member, a recessed portion formed by the first heat dissipation member portion and the second heat dissipation member portion accommodates the first solder and the insulating substrate.

2. The semiconductor device according to claim 1, wherein The insulating substrate comprises a base material, One or more conductor layers are bonded to one surface of the substrate and to another surface on the side opposite to the one surface. The first solder is bonded to the entire surface of the conductor layer on the other surface. The first solder gradually becomes thicker from a central portion toward end portions in a plan view.

3. The semiconductor device according to claim 1 or 2, wherein: The electrode plate includes a main terminal side end portion serving as a main terminal and a semiconductor element side end portion serving as an end portion on the opposite side to the main terminal side end portion. The main terminal side end portion includes a first portion exposed to the outside of the frame member and a second portion embedded in the frame member.

4. The semiconductor device according to claim 1, wherein It also has main terminals. The main terminal includes a connection portion exposed from the frame member on the inner side of the frame member, The electrode plate includes a main terminal side end portion connected to the main terminal and a semiconductor element side end portion which is an end portion on the opposite side to the main terminal side end portion. The main terminal side end portion of the electrode plate and the connection portion are joined by a third solder.

5. The semiconductor device according to claim 1, wherein It also has main terminals. The main terminal includes a connection portion exposed from the frame member on the inner side of the frame member, The electrode plate includes a main terminal side end portion connected to the main terminal and a semiconductor element side end portion which is an end portion on the opposite side to the main terminal side end portion. The main terminal side end portion of the electrode plate and the connection portion are bonded by a bonding wire.

6. The semiconductor device according to claim 1 or 2, wherein: The heat dissipating member includes a protrusion having a vertex at a position overlapping a region where the temperature of the insulating substrate becomes highest when viewed from above.

7. The semiconductor device according to claim 1 or 2, wherein: further comprising a sealing resin for sealing the semiconductor element, The first solder is in contact with the sealing resin.

8. A semiconductor device comprising: Insulating substrate, carrying semiconductor components; a heat dissipation component joined to the insulating substrate via a first solder; and The electrode plate is arranged so as to overlap at least a portion of the semiconductor element. The main surface of the insulating substrate is warped so that the insulating substrate has a convex shape that protrudes toward the heat dissipating member and straddles the plurality of semiconductor elements. The first solder is thicker at the end portion than at the center portion when viewed from above, The semiconductor element is bonded to the electrode plate via a second solder. The semiconductor device further includes a frame member disposed so as to surround the insulating substrate at a distance from the insulating substrate. The electrode plate is arranged in the frame member so as to face the insulating substrate. The main surface of the electrode plate is warped in such a manner that the electrode plate follows the convex shape of the insulating substrate, The heat dissipation component comprises: a first heat dissipation component portion joined to the insulating substrate via the first solder; as well as The second heat dissipation component surrounds the first heat dissipation component and the first solder on the outer side of the first heat dissipation component in a plan view and is provided with the frame member. In the heat dissipation member, a recessed portion formed by the first heat dissipation member portion and the second heat dissipation member portion accommodates the first solder and the insulating substrate.

9. The semiconductor device according to claim 8, wherein: The insulating substrate comprises a base material, One or more conductor layers are bonded to one surface of the substrate and to another surface on the side opposite to the one surface. The first solder is bonded to the entire surface of the conductor layer on the other surface. The first solder gradually becomes thicker from a central portion toward end portions in a plan view.

10. The semiconductor device according to claim 8 or 9, wherein: The electrode plate includes a main terminal side end portion serving as a main terminal and a semiconductor element side end portion serving as an end portion on the opposite side to the main terminal side end portion. The main terminal side end portion includes a first portion exposed to the outside of the frame member and a second portion embedded in the frame member.

11. The semiconductor device according to claim 8 or 9, wherein: The heat dissipating member includes a protrusion having a vertex at a position overlapping a region where the temperature of the insulating substrate is highest when viewed from above.

12. The semiconductor device according to claim 8 or 9, wherein: further comprising a sealing resin for sealing the semiconductor element, The first solder is in contact with the sealing resin.

13. A method for manufacturing a semiconductor device, comprising: A step of bonding the heat dissipation component and the insulating substrate using a first solder; a step of bonding a semiconductor element to the insulating substrate; and After the step of bonding with the first solder and the step of bonding the semiconductor element, a step of bonding the electrode plate overlapping at least a portion of the semiconductor element to the semiconductor element with the second solder, The insulating substrate is bonded to the heat dissipating member in such a manner that the main surface thereof is warped to have a convex shape toward the heat dissipating member. The first solder is formed to be thicker at the end portion than at the center portion in a plan view, The method for manufacturing a semiconductor device further comprises: a step of preparing a frame member, the frame member being arranged to surround the insulating substrate with a gap therebetween and having main terminals embedded therein; and After the step of bonding the semiconductor element with the second solder, a step of bonding the electrode plate with the main terminal with the third solder is performed. The heat dissipation component comprises: a first heat dissipation component portion joined to the insulating substrate via the first solder; as well as The second heat dissipation component surrounds the first heat dissipation component and the first solder on the outer side of the first heat dissipation component in a plan view and is provided with the frame member. In the heat dissipation member, a recessed portion formed by the first heat dissipation member portion and the second heat dissipation member portion accommodates the first solder and the insulating substrate.

14. The method for manufacturing a semiconductor device according to claim 13, wherein: The insulating substrate comprises a base material, One or more conductor layers are bonded to one surface of the substrate and to another surface on the side opposite to the one surface. The warping of the convex shape is adjusted by adjusting the difference in area between a first region on the one surface to which the conductive layer is not bonded and a second region on the other surface to which the conductive layer is not bonded.

15. The method for manufacturing a semiconductor device according to claim 14, wherein: The warping of the convex shape is adjusted by forming the conductor layer on the one surface thicker than the conductor layer on the other surface.

16. The method for manufacturing a semiconductor device according to claim 14, wherein: The warping of the convex shape is adjusted by further comprising the step of bonding another conductive layer between the conductive layer on the one surface and the semiconductor element so as to overlap with the conductive layer.

17. A method for manufacturing a semiconductor device, comprising: A step of bonding the heat dissipation component and the insulating substrate using a first solder; a step of bonding a semiconductor element to the insulating substrate; and After the step of bonding with the first solder and the step of bonding the semiconductor element, a step of bonding the electrode plate overlapping at least a portion of the semiconductor element to the semiconductor element with the second solder, The insulating substrate is bonded to the heat dissipating member in such a manner that the main surface thereof is warped to have a convex shape toward the heat dissipating member. The first solder is formed to be thicker at the end portion than at the center portion in a plan view, The method for manufacturing a semiconductor device further comprises: a step of preparing a frame member, the frame member being arranged to surround the insulating substrate with a gap therebetween and having main terminals embedded therein; and After the step of bonding the semiconductor element with the second solder, a step of wire bonding the electrode plate and the main terminal, The heat dissipation component comprises: a first heat dissipation component portion joined to the insulating substrate via the first solder; as well as The second heat dissipation component surrounds the first heat dissipation component and the first solder on the outer side of the first heat dissipation component in a plan view and is provided with the frame member. In the heat dissipation member, a recessed portion formed by the first heat dissipation member portion and the second heat dissipation member portion accommodates the first solder and the insulating substrate.

18. The method for manufacturing a semiconductor device according to claim 17, wherein: The insulating substrate comprises a base material, One or more conductor layers are bonded to one surface of the substrate and to another surface on the side opposite to the one surface. The warping of the convex shape is adjusted by adjusting the difference in area between a first region on the one surface to which the conductive layer is not bonded and a second region on the other surface to which the conductive layer is not bonded.

19. The method for manufacturing a semiconductor device according to claim 18, wherein: The warping of the convex shape is adjusted by forming the conductor layer on the one surface thicker than the conductor layer on the other surface.

20. The method for manufacturing a semiconductor device according to claim 18, wherein: The warping of the convex shape is adjusted by further comprising the step of bonding another conductive layer between the conductive layer on the one surface and the semiconductor element so as to overlap with the conductive layer.

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