semiconductor devices

Abstract

The semiconductor device (A1) of the present invention comprises: a support member (2); a metal member (30) having a main surface (301) and a back surface (302) separated in the z direction, with the back surface (302) facing the support member (2) and bonded to the support member (2); a second bonding layer (42) bonding the support member (2) and the metal member (30); a semiconductor element (10) facing the main surface (301) and bonded to the metal member (30); and a sealing member (7) covering the support member (2), the metal member (30), the second bonding layer (42) and the semiconductor element (10). The metal member (30) includes a first metal body (31) composed of a first metal material and a second metal body (32) composed of a second metal material, and has a boundary between the first metal body (31) and the second metal body (32). The linear expansion coefficient of the second metal material is smaller than the linear expansion coefficient of the first metal material. A semiconductor device can be provided that achieves improved reliability by alleviating thermal stress when the semiconductor element generates heat.

Description

Technical Field

[0001] The present invention relates to a semiconductor device having a semiconductor element mounted thereon. Background Art

[0002] In recent years, semiconductor devices equipped with semiconductor elements such as MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) and IGBT (Insulated Gate Bipolar Transistor) have become known. Patent Document 1 discloses an example of a semiconductor device equipped with a semiconductor element. The semiconductor device described in Patent Document 1 includes a semiconductor element, a support component, a heat diffusion plate, and a sealing component. The semiconductor element is joined to the heat diffusion plate by solder. The support component includes a conductive pattern, a metal plate, and an insulating resin. The support component is formed with an insulating resin (for example, ceramic) on the upper surface of a metal plate (for example, a metal such as aluminum, copper, or an alloy thereof), and a conductive pattern (for example, a metal such as aluminum, copper, or an alloy thereof) is formed on the insulating resin. The heat diffusion plate is a plate-shaped component made of, for example, copper or a copper alloy. The heat diffusion plate is joined to the conductive pattern of the support component by solder. The sealing component covers the semiconductor element, a portion of the support component, the heat diffusion plate, and each solder.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2008-294390 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] When power is applied to a semiconductor device, heat is generated from the semiconductor element. As the temperature of the semiconductor element rises due to heat generation, thermal stress is applied to the solder joining the heat spreader plate and the supporting member due to thermal expansion of the component parts. This thermal stress can cause cohesive failure of the solder, leading to product failures such as poor bonding and poor conductivity.

[0008] The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a semiconductor device that can improve reliability by alleviating thermal stress caused by heat generation in a semiconductor element.

[0009] Solutions to Problems

[0010] The semiconductor device of the present invention comprises: a supporting component; a metal component having a first main surface and a first back surface separated in the thickness direction, the first back surface being opposite to the supporting component and bonded to the supporting component; a bonding layer bonding the supporting component and the metal component; a semiconductor element being opposite to the first main surface and bonded to the metal component; and a sealing component covering the supporting component, the metal component, the bonding layer and the semiconductor element, the metal component including a first metal body formed of a first metal material and a second metal body formed of a second metal material, and having a boundary between the first metal body and the second metal body, and the linear expansion coefficient of the second metal material being smaller than the linear expansion coefficient of the first metal material.

[0011] Effects of the Invention

[0012] According to the semiconductor device of the present invention, thermal stress caused by heat generation in the semiconductor element can be alleviated, thereby improving the reliability of the semiconductor device. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a perspective view showing the semiconductor device according to the first embodiment.

[0014] Figure 2 It is a plan view showing the semiconductor device according to the first embodiment.

[0015] Figure 3 is Figure 2 The sealing component is shown by an imaginary line (two-dot chain line) in the top view of FIG.

[0016] Figure 4 It is a bottom view showing the semiconductor device according to the first embodiment.

[0017] Figure 5 It is a side view (right side view) showing the semiconductor device according to the first embodiment.

[0018] Figure 6 It is a side view (left side view) showing the semiconductor device according to the first embodiment.

[0019] Figure 7 It is a front view showing the semiconductor device according to the first embodiment.

[0020] Figure 8 It is along Figure 3 Cross-sectional view along line VIII-VIII.

[0021] Figure 9 It is along Figure 3 Cross-sectional view of line IX-IX.

[0022] Figure 10 It is along Figure 3 X-ray cross-sectional view.

[0023] Figure 11 It is along Figure 3 Cross-sectional view of line XI-XI.

[0024] Figure 12 It is magnified Figure 3 A partial enlarged view of a part of .

[0025] Figure 13 It is along Figure 12 Cross-sectional view along line XIII-XIII.

[0026] Figure 14 It is a schematic cross-sectional view of the metal component of the first embodiment.

[0027] Figure 15 It is a plan view showing a semiconductor device according to a second embodiment.

[0028] Figure 16 It is a plan view showing a semiconductor device according to a third embodiment.

[0029] Figure 17 It is along Figure 16 Cross-sectional view along line XVII-XVII.

[0030] Figure 18 It is a partial cross-sectional view of a metal component showing a modified example. DETAILED DESCRIPTION

[0031] Hereinafter, preferred embodiments of the semiconductor device of the present invention will be described with reference to the accompanying drawings. The same or similar components are denoted by the same reference numerals, and redundant descriptions will be omitted.

[0032] Figures 1 to 14 The semiconductor device A1 of the first embodiment is shown. The semiconductor device A1 includes a plurality of semiconductor elements 10, a support member 2, a plurality of metal members 30, a plurality of first bonding layers 41, a plurality of second bonding layers 42, a pair of input terminals 51, a pair of output terminals 52, a plurality of control terminals 53, a plurality of detection terminals 54, a plurality of connection members 6, and a sealing member 7.

[0033] Figure 1 It is a perspective view showing the semiconductor device A1. Figure 2 It is a top view showing the semiconductor device A1. Figure 3 is Figure 2 The sealing member 7 is shown by an imaginary line (two-dot chain line) in the top view of FIG. Figure 4 It is a bottom view showing the semiconductor device A1. Figure 5 It is a side view (right side view) showing the semiconductor device A1. Figure 6 It is a side view (left side view) showing the semiconductor device A1. Figure 7 It is a front view showing the semiconductor device A1. Figure 8 It is along Figure 3 Cross-sectional view along line VIII-VIII. Figure 9 It is along Figure 3 Cross-sectional view of line IX-IX. Figure 10 It is along Figure 3 X-ray cross-sectional view. Figure 11 It is along Figure 3 Cross-sectional view of line XI-XI. Figure 12 It is magnified Figure 3 A partial enlarged view of a part of . Figure 13 It is along Figure 12 Cross-sectional view along line XIII-XIII. Figure 14 3 is a schematic cross-sectional view of the metal component 30 .

[0034] For the sake of convenience, three mutually orthogonal directions are defined as x-direction, y-direction, and z-direction. The z-direction is the thickness direction of the semiconductor device A1. The x-direction is the top view of the semiconductor device A1 (see Figure 2 ) in the left-right direction. The y direction is the top view of the semiconductor device A1 (see Figure 2 ) in the up and down directions. Furthermore, one side of the x-direction is referred to as the x1 direction, and the other side of the x-direction is referred to as the x2 direction. Similarly, one side of the y-direction is referred to as the y1 direction, and the other side of the y-direction is referred to as the y2 direction. One side of the z-direction is referred to as the z1 direction, and the other side of the z-direction is referred to as the z2 direction. In this disclosure, the z1 direction is sometimes referred to as down, and the z2 direction is sometimes referred to as up.

[0035] The semiconductor device A1 is a power conversion device (power module) used in, for example, a motor drive source, an inverter device of various electrical products, and a DC / DC converter of various electrical products. The semiconductor device A1 forms, for example, a half-bridge switching circuit.

[0036] The plurality of semiconductor elements 10 are, for example, MOSFETs. In addition, each semiconductor element 10 is not limited to MOSFETs, but may also be a switching element such as a field effect transistor including a MISFET (Metal-Insulator-Semiconductor FET) or a bipolar transistor including an IGBT. Alternatively, each semiconductor element 10 may not only be a switching element, but also an IC chip such as an LSI, a diode, a capacitor, etc. In this embodiment, each semiconductor element 10 is shown as an n-channel MOSFET, but may also be a p-channel type. Each semiconductor element 10 is composed of a semiconductor material mainly composed of SiC (silicon carbide). In addition, the semiconductor material is not limited to SiC, but may also be Si (silicon), GaAs (gallium arsenide), GaN (gallium nitride), or Ga2O3 (gallium oxide), etc.

[0037] Each semiconductor element 10 is bonded to any one of the plurality of metal members 30 via the first bonding layer 41. Each semiconductor element 10 has a rectangular shape when viewed in the z direction (hereinafter also referred to as "plan view"), for example.

[0038] like Figure 13 As shown, each semiconductor element 10 has a main surface 101 and a back surface 102. The main surface 101 and the back surface 102 are separated from each other in the z-direction. The main surface 101 faces the z2 direction, and the back surface 102 faces the z1 direction. The back surface 102 is in contact with the first bonding layer 41 and faces any one of the plurality of metal components 30.

[0039] like Figure 12 and Figure 13 As shown, each semiconductor element 10 includes a first electrode 11 , a second electrode 12 , a third electrode 13 , and an insulating film 14 .

[0040] The first electrode 11 is arranged on the main surface 101 side in the z direction in each semiconductor element 10. The first electrode 11 is exposed on the main surface 101 of the semiconductor element 10. The first electrode 11 is, for example, a source electrode, through which a source current flows. Figure 12 As shown, the first electrode 11 is divided into, for example, four sections.

[0041] The second electrode 12 is arranged on the back surface 102 side in the z direction in each semiconductor element 10. The second electrode 12 is exposed on the back surface 102 of the semiconductor element 10. The second electrode 12 is, for example, a drain electrode, and drain current flows therethrough.

[0042] The third electrode 13 is arranged on the main surface 101 side in the z direction of each semiconductor element 10. The third electrode 13 is exposed on the main surface 101 of the semiconductor element 10. The third electrode 13 is, for example, a gate electrode, to which a gate voltage (control voltage) is applied for driving the semiconductor element 10. In a plan view, the size of the third electrode 13 is smaller than the size of one portion of the first electrode 11 divided into four.

[0043] The insulating film 14 is disposed on the main surface 101 side in the z direction of each semiconductor element 10. The third electrode 13 is exposed on the main surface 101 of the semiconductor element 10. The insulating film 14 surrounds the first electrode 11 and the third electrode 13, respectively, when viewed from above. The insulating film 14 insulates the first electrode 11 from the third electrode 13. The insulating film 14 is, for example, a film formed by sequentially stacking a SiO2 (silicon dioxide) layer, a SiN4 (silicon nitride) layer, and a polybenzoxazole layer. The polybenzoxazole layer is the surface layer on the main surface 101 side of each semiconductor element 10. Alternatively, a polyimide layer may be used in the insulating film 14 instead of the polybenzoxazole layer.

[0044] The plurality of semiconductor elements 10 include a plurality of first elements 10A and a plurality of second elements 10B. As described above, the semiconductor device A1 forms a half-bridge switching circuit. The plurality of first elements 10A form the upper arm circuit of the switching circuit. The plurality of second elements 10B form the lower arm circuit of the switching circuit. Figure 3 As shown, the semiconductor device A1 includes two (a pair) of first elements 10A and two (a pair) of second elements 10B. The number of semiconductor elements 10 is not limited to this structure and can be freely set according to the performance required of the semiconductor device A1.

[0045] The support member 2 supports the plurality of semiconductor elements 10 via the plurality of metal members 30. The support member 2 includes an insulating substrate 21 and a plurality of wiring layers 22.

[0046] A plurality of wiring layers 22 are arranged on the insulating substrate 21. The insulating substrate 21 has electrical insulation properties. The constituent material of the insulating substrate 21 is, for example, a ceramic having excellent thermal conductivity. Examples of such ceramics include AlN (aluminum nitride), SiN (silicon nitride), and Al2O3 (aluminum oxide). The insulating substrate 21 is in the form of a flat plate. Figure 3 As shown in FIG, the insulating substrate 21 has a rectangular shape when viewed from above. The thickness (dimension in the z direction) of each insulating substrate 21 is not less than 0.2 mm and not more than 1.0 mm (for example, 0.5 mm).

[0047] like Figures 8 to 11As shown, the insulating substrate 21 has a main surface 211 and a back surface 212. The main surface 211 and the back surface 212 are separated from each other in the z direction. The main surface 211 faces the z2 direction, and the back surface 212 faces the z1 direction. The back surface 212 is exposed from the sealing component 7. A heat sink, for example, not shown in the figure, is connected to the back surface 212. In addition, the structure of the insulating substrate 21 is not limited to the structure shown in the figure, and multiple wiring layers 22 can also be provided individually. The main surface 211 is equivalent to the "second main surface" recorded in the claims, and the back surface 212 is equivalent to the "second back surface" recorded in the claims.

[0048] A plurality of wiring layers 22 are respectively formed on the main surface 211 of the insulating substrate 21. The plurality of wiring layers 22 are separated from each other. Each wiring layer 22 is made of a metal containing silver, for example. In addition, the constituent material of each wiring layer 22 is not limited to a metal containing silver. For example, it may be a metal containing copper, or the metal containing copper may be plated with silver. In addition, instead of the silver plating, a plurality of metal platings such as an aluminum layer, a nickel layer, and a silver layer may be sequentially stacked. The plurality of wiring layers 22 are all located inward of the periphery of the insulating substrate 21 when viewed from above. Each wiring layer 22 is rectangular when viewed from above. Each wiring layer 22 is covered by a sealing component 7. The thickness (dimension in the z direction) of each wiring layer 22 is not less than 5 μm and not more than 80 μm.

[0049] like Figure 3 As shown, the plurality of wiring layers 22 include a pair of first wiring layers 22A, a pair of second wiring layers 22B, and a third wiring layer 22C. The pair of first wiring layers 22A, the pair of second wiring layers 22B, and the third wiring layer 22C are separated from each other in a plan view.

[0050] The pair of first wiring layers 22A is located on the x1 direction side on the insulating substrate 21. The first wiring layers 22A are separated from each other in the y direction.

[0051] The pair of second wiring layers 22B are located on the x2 side of the insulating substrate 21. The pair of second wiring layers 22B are separated from each other in the y direction. The pair of second wiring layers 22B are located next to the pair of first wiring layers 22A in the x direction.

[0052] The third wiring layer 22C is located on the x1 direction side on the insulating substrate 21. The third wiring layer 22C is located between the pair of first wiring layers 22A.

[0053] Each of the plurality of wiring layers 22 (a pair of first wiring layers 22A, a pair of second wiring layers 22B, and a third wiring layer 22C) has a main surface 221 and a back surface 222. The main surface 221 and the back surface 222 are separated from each other in the z-direction. The main surface 221 faces the z2 direction, and the back surface 222 faces the z1 direction. When each wiring layer 22 is bonded to the insulating substrate 21, the back surface 222 faces the main surface 211 of the insulating substrate 21. The main surface 221 corresponds to the "third main surface" described in the claims, and the back surface 222 corresponds to the "third back surface" described in the claims.

[0054] A plurality of metal components 30 are disposed one on each wiring layer 22. Each metal component 30 is bonded to each wiring layer 22 (support component 2) via a second bonding layer 42. The plurality of metal components 30 are bonded to the plurality of semiconductor elements 10 via a first bonding layer 41. The thickness (z-direction dimension) of each metal component 30 is not less than 0.5 mm and not more than 5 mm (preferably not less than 1.0 mm and not more than 3 mm).

[0055] like Figure 3 As shown, the plurality of metal components 30 include a pair of first metal components 30A, a pair of second metal components 30B, and a third metal component 30C. The pair of first metal components 30A, the pair of second metal components 30B, and the third metal component 30C are separated from each other in a plan view.

[0056] like Figure 3 and Figure 10 As shown, a pair of first metal members 30A are respectively arranged on a pair of first wiring layers 22A. Each first element 10A is bonded to each first metal member 30A.

[0057] like Figure 3 、 Figure 8 as well as Figure 9 As shown, a pair of second metal members 30B are respectively arranged on a pair of second wiring layers 22B. Each second element 10B is bonded to each second metal member 30B.

[0058] like Figure 3 、 Figure 9 as well as Figure 10 As shown, the third metal member 30C is disposed on the third wiring layer 22C. None of the plurality of semiconductor elements 10 is bonded to the third metal member 30C. Furthermore, since none of the plurality of semiconductor elements 10 is bonded to the third metal member 30C, the semiconductor device A1 may not include the third metal member 30C.

[0059] like Figures 8 to 11 as well as Figure 13As shown, the plurality of metal components 30 (a pair of first metal components 30A, a pair of second metal components 30B, and a third metal component 30C) each has a main surface 301 , a rear surface 302 , and a plurality of side surfaces 303 .

[0060] The main surface 301 and the back surface 302 are separated from each other in the z-direction. The main surface 301 faces the z2 direction, and the back surface 302 faces the z1 direction. When each semiconductor element 10 is bonded to each metal component 30, the main surface 301 faces the main surface 101 of each semiconductor element 10. When each metal component 30 is bonded to each wiring layer 22, the back surface 302 faces the main surface 221 of each wiring layer 22. The main surface 301 corresponds to the "first main surface" described in the claims, and the back surface 302 corresponds to the "first back surface" described in the claims.

[0061] The plurality of side surfaces 303 are sandwiched between the main surface 301 and the back surface 302 in the z-direction and are connected to both. Each metal component 30 has a pair of side surfaces 303 separated in the x-direction and facing opposite sides, and a pair of side surfaces 303 separated in the y-direction and facing opposite sides, for a total of four side surfaces 303.

[0062] like Figure 13 and Figure 14 As shown, the plurality of metal components 30 (a pair of first metal components 30A, a pair of second metal components 30B, and a third metal component 30C) include a first metal body 31 and a second metal body 32. The first metal body 31 is made of a first metal material, and the second metal body 32 is made of a second metal material. The linear expansion coefficient of the second metal material is smaller than that of the first metal material. In other words, the linear expansion coefficient of the second metal body 32 is smaller than that of the first metal body 31. Furthermore, the linear expansion coefficient of the second metal material is closer to that of the insulating substrate 21 (support component 2) than that of the first metal material. For example, the first metal material is a metal containing Cu (copper), and the second metal material is a metal containing Mo (molybdenum). The linear expansion coefficient of Cu is approximately 16 ppm / K, and the linear expansion coefficient of Mo is approximately 5.1 ppm / K. Furthermore, the content of the second metal body 32 in each metal component 30 is 10% or more and 40% or less (preferably 30%). Furthermore, the second metal material is not limited to a metal containing Mo and may also be a metal containing W (tungsten).

[0063] In each metal component 30, the first metal body 31 includes a plurality of first metal layers 311, and the plurality of second metal bodies 32 include a plurality of second metal layers 321. Figure 13In the example shown, the first metal body 31 includes seven first metal layers 311, and the second metal body 32 includes six second metal layers 321. Each metal component 30 forms a stacked structure in which a plurality of first metal layers 311 and a plurality of second metal layers 321 are alternately stacked in the z direction. In each metal component 30, as shown in FIG. Figure 13 As shown, the plurality of first metal layers 311 include a surface layer on the main surface 301 side and a surface layer on the back surface 302 side. Thus, the top layer and the bottom layer of the stacked structure of each metal component 30 belong to the plurality of first metal layers 311 respectively. The thickness of each first metal layer 311 is greater than the thickness of each second metal layer 321. For example, the thickness of each first metal layer 311 is greater than 0.1 mm and less than 0.8 mm (preferably greater than 0.2 mm and less than 0.4 mm), and the thickness of each second metal layer 321 is greater than 0.1 mm and less than 0.5 mm (preferably 0.1 mm). In addition, the number of the first metal layer 311 and the second metal layer 321 is not particularly limited. For example, in order to make the surface layer on the main surface 301 side and the surface layer on the back surface 302 side both the first metal layer 311, it is necessary to make the number of the first metal layer 311 greater than the number of the second metal layer 321.

[0064] like Figure 13 and Figure 14 As shown, each metal component 30 has a plurality of interfaces 33. Each interface 33 is a boundary between each first metal layer 311 and each second metal layer 321 that are in contact with each other. Furthermore, each metal component 30 contains a crack 34 extending from any one of the plurality of side surfaces 303 toward the inside of the metal component 30 when viewed from above. The crack 34 extends from the side surface 303 by more than 10 μm and less than 100 μm (preferably more than 20 μm and less than 40 μm). The crack 34 is formed by local peeling of each interface 33. Thus, the interface 33 formed by each first metal layer 311 and each second metal layer 321 has portions that abut each other and portions that do not abut due to the crack 34. In addition, the crack 34 does not need to be formed on all interfaces 33, but only needs to be formed on more than one interface 33. In addition, the crack 34 does not need to extend from all side surfaces 303, but only needs to extend from more than one side surface 303. As shown Figure 14 As shown, the cracks 34 are filled with the sealing member 7. In addition, the cracks 34 may not be formed in each metal member 30.

[0065] As described above, each metal component 30 is composed of a plurality of first metal layers 311 formed from a first metal material (e.g., Cu) and a plurality of second metal layers 321 formed from a second metal material (e.g., Mo). Furthermore, the linear expansion coefficient of the second metal material is smaller than that of the first metal material. Consequently, the linear expansion coefficient of each metal component 30 is smaller than that of a component composed solely of the first metal material. In semiconductor device A1, the linear expansion coefficient of each metal component 30 is greater than 3 ppm / K and less than 14 ppm / K (preferably greater than 7 ppm / K and less than 11 ppm / K).

[0066] Multiple first bonding layers 41 are interposed between each semiconductor element 10 and each metal component 30, bonding them together. The first bonding layers 41 are, for example, solder. This solder may contain lead or be lead-free. Furthermore, each first bonding layer 41 is not limited to solder and may also be another conductive bonding material such as sintered metal. The first bonding layers 41 correspond to the "conductive bonding material" described in the claims.

[0067] Multiple second bonding layers 42 are interposed between each metal component 30 and each wiring layer 22, bonding them together. Each second bonding layer 42 is, for example, solder. The solder may contain lead or be lead-free. In addition, each second bonding layer 42 is not limited to solder and may also be other conductive bonding materials such as sintered metal, or an insulating bonding material (adhesive). The second bonding layer 42 corresponds to the "bonding layer" described in the claims.

[0068] The pair of input terminals 51, the pair of output terminals 52, the control terminals 53, and the detection terminals 54 are each made of copper or a copper alloy and are formed from the same lead frame.

[0069] like Figures 1 to 4 As shown, a pair of input terminals 51 are located on the x1 side of semiconductor device A1. The pair of input terminals 51 are separated from each other in the y direction. The pair of input terminals 51 are connected to an external DC power supply. For example, a DC voltage is applied between the pair of input terminals 51. Each of the pair of input terminals 51 is partially covered by the sealing member 7, thereby being supported by the sealing member 7.

[0070] The pair of input terminals 51 includes a first input terminal 51A and a second input terminal 51B. The first input terminal 51A is a positive terminal (P terminal), and the second input terminal 51B is a negative terminal (N terminal). The first input terminal 51A and the second input terminal 51B (the pair of input terminals 51) each include a pad portion 511 and a terminal portion 512.

[0071] The pad portion 511 is located outside the periphery of the support member 2 in a plan view and is separated in the z direction from the support member 2. The pad portion 511 is covered with the sealing member 7. The surface of the pad portion 511 may be plated with silver, for example.

[0072] Terminal portion 512 is connected to pad portion 511 and is exposed from sealing member 7. Terminal portion 512 is used when semiconductor device A1 is mounted on a wiring board. Terminal portion 512 is L-shaped when viewed along the y direction. The surface of terminal portion 512 may be plated with nickel, for example.

[0073] Terminal portion 512 includes base portion 513 and rising portion 514. Base portion 513 is connected to pad portion 511 and extends from sealing member 7 (side surface 731 described later) in the x direction. Standing portion 514 extends from the x-direction tip of base portion 513 in the z2 direction.

[0074] like Figures 1 to 4 As shown, a pair of output terminals 52 are located on the x2 direction side in the semiconductor device A1. Figures 1 to 4 As shown, the pair of output terminals 52 are separated from each other in the y direction. AC power (AC voltage) converted by the plurality of semiconductor elements 10 is output from the pair of output terminals 52. Each of the pair of output terminals 52 is partially covered by the sealing member 7 and thus supported by the sealing member 7. The pair of output terminals 52 each includes a pad portion 521 and a terminal portion 522.

[0075] The pad portion 521 is located outside the periphery of the support member 2 in a plan view and is separated in the z direction from the support member 2. The pad portion 521 is covered with a sealing member 7. The surface of the pad portion 521 may be plated with silver, for example.

[0076] Terminal portion 522 is connected to pad portion 521 and is exposed from sealing member 7. Terminal portion 522 is used when semiconductor device A1 is mounted on a wiring board. Terminal portion 522 is L-shaped when viewed along the y-direction. The shape of terminal portion 522 is substantially the same as that of terminal portion 512 of each input terminal 51. Furthermore, the surface of terminal portion 522 may be nickel-plated, for example.

[0077] The terminal portion 522 includes a base portion 523 and an upright portion 524. The base portion 523 is connected to the pad portion 521 and extends from the sealing member 7 (side surface 732 described later) in the x direction. The upright portion 524 extends from the x-direction tip of the base portion 523 in the z2 direction.

[0078] like Figures 1 to 4As shown, multiple control terminals 53 are located on both sides of the semiconductor device A1 in the x-direction. The multiple control terminals 53 located on the x1 side are located between a pair of input terminals 51 in the y-direction. The multiple control terminals 53 located on the x2 side are located between a pair of output terminals 52 in the y-direction. The number of control terminals 53 corresponds to the number of semiconductor elements 10. Thus, the semiconductor device A1 has four control terminals 53. A control voltage (gate voltage) for driving each semiconductor element 10 is applied to each control terminal 53. Each control terminal 53 is partially covered by the sealing member 7 and is thereby supported by the sealing member 7. Each control terminal 53 includes a pad portion 531 and a terminal portion 532.

[0079] The pad portion 531 is located outside the periphery of the support member 2 in a plan view and is separated in the z direction from the support member 2. The pad portion 531 is covered with the sealing member 7. The surface of the pad portion 531 may be plated with silver, for example.

[0080] Terminal portion 532 is connected to pad portion 531 and is exposed from sealing member 7. Terminal portion 532 is used when semiconductor device A1 is mounted on a wiring board. Terminal portion 532 is L-shaped when viewed in the y direction. The surface of terminal portion 532 may be plated with nickel, for example.

[0081] The terminal portion 532 includes a base portion 533 and a rising portion 534. The base portion 533 is connected to the pad portion 531 and extends in the x-direction from the sealing member 7 (either the side surface 731 or the side surface 732 described later). The x-direction dimension of the base portion 533 is smaller than the x-direction dimensions of the base portions 513 of the pair of input terminals 51 and the base portions 523 of the pair of output terminals 52. The rising portion 534 extends from the x-direction tip of the base portion 533 in the z2 direction.

[0082] like Figures 1 to 4 As shown, multiple detection terminals 54 are located on both sides of the semiconductor device A1 in the x-direction. The multiple detection terminals 54 located on the x1 side are located between a pair of input terminals 51 in the y-direction. The multiple detection terminals 54 located on the x2 side are located between a pair of output terminals 52 in the y-direction. In this embodiment, the number of detection terminals 54 corresponds to the number of semiconductor elements 10. Thus, the semiconductor device A1 has four detection terminals 54. A voltage corresponding to the current flowing through the first electrode 11 (source electrode) of each semiconductor element 10 is applied to each detection terminal 54. Each detection terminal 54 includes a pad portion 541 and a terminal portion 542.

[0083] The pad portion 541 is located outside the periphery of the support member 2 in a plan view and is separated in the z direction from the support member 2. The pad portion 541 is covered with the sealing member 7. The surface of the pad portion 541 may be plated with silver, for example.

[0084] Terminal portion 542 is connected to pad portion 541 and is exposed from sealing member 7. Terminal portion 542 is used when semiconductor device A1 is mounted on a wiring board. Terminal portion 542 is L-shaped when viewed along the y direction. The surface of terminal portion 542 may be plated with nickel, for example.

[0085] The terminal portion 542 includes a base portion 543 and a rising portion 544. The base portion 543 is connected to the pad portion 531 and extends in the x-direction from the sealing member 7 (either the side surface 731 or the side surface 732 described later). The x-direction dimension of the base portion 543 is approximately the same as the x-direction dimension of the base portion 533 of each control terminal 53, and is smaller than the x-direction dimensions of the base portions 513 of the pair of input terminals 51 and the base portions 523 of the pair of output terminals 52. The rising portion 544 extends from the x-direction tip of the base portion 543 in the z2 direction.

[0086] A plurality of connecting components 6 respectively connect two separated components. Figure 3 As shown, the plurality of connection components 6 include a plurality of first wires 611 , a plurality of second wires 612 , a plurality of third wires 613 , a plurality of fourth wires 614 , a first conductive component 621 , a second conductive component 622 , a third conductive component 623 and a fourth conductive component 624 .

[0087] A plurality of first wires 611 are bonded to the first electrodes 11 of the pair of first elements 10A and the main surfaces 301 of the pair of second metal members 30B. Thus, each second metal member 30B (each second wiring layer 22B) is electrically connected to the first electrode 11 of each first element 10A via each first wire 611. The constituent material of each first wire 611 is, for example, a metal containing aluminum, a metal containing copper, or a metal containing gold.

[0088] A plurality of second wires 612 are bonded to the first electrodes 11 of the pair of second elements 10B and the main surface 301 of the third metal member 30C. Thus, the third metal member 30C (third wiring layer 22C) is electrically connected to the first electrodes 11 of the second elements 10B via the second wires 612. The material constituting each second wire 612 is, for example, a metal containing aluminum, a metal containing copper, or a metal containing gold.

[0089] The plurality of third wires 613 are respectively connected to the third electrodes 13 of the plurality of semiconductor elements 10 and the pad portions 531 of the plurality of control terminals 53. Thus, each control terminal 53 is electrically connected to the third electrode 13 of each semiconductor element 10 via each third wire 613. The constituent material of each third wire 613 is, for example, a metal containing aluminum, a metal containing copper, or a metal containing gold.

[0090] The plurality of fourth wires 614 are respectively connected to the first electrodes 11 of the plurality of semiconductor elements 10 and the pad portions 541 of the plurality of detection terminals 54. Thus, each detection terminal 54 is electrically connected to the first electrode 11 of each semiconductor element 10 via each fourth wire 614. The constituent material of each fourth wire 614 is, for example, a metal containing aluminum, a metal containing copper, or a metal containing gold.

[0091] like Figure 3 and Figure 10 As shown, the first conductive component 621 is bonded to the main surface 301 of one first metal component 30A and the main surface 301 of the other first metal component 30A. As a result, the pair of first metal components 30A (a pair of first wiring layers 22A) are electrically connected to each other. The first conductive component 621 extends in the y direction when viewed from above and crosses the third wiring layer 22C. Figure 3 As shown, the first conductive member 621 is formed of, for example, a plurality of bonding wires. The bonding wires are made of, for example, a metal containing aluminum, a metal containing copper, or a metal containing gold.

[0092] like Figure 3 and Figure 8 As shown, the second conductive component 622 is bonded to the pad portion 511 of the first input terminal 51A and the main surface 301 of the first metal component 30A. As a result, the first input terminal 51A is electrically connected to the first metal component 30A (the first wiring layer 22A) via the second conductive component 622. As a result, the first input terminal 51A is electrically connected to the second electrode 12 of the first element 10A via the second conductive component 622 and the first metal component 30A (the first wiring layer 22A). Figure 3 As shown, the second conductive member 622 is formed of, for example, a plurality of bonding wires. The bonding wires are made of, for example, a metal containing aluminum, a metal containing copper, or a metal containing gold.

[0093] like Figure 3 As shown, the third conductive component 623 is bonded to the pad portion 511 of the second input terminal 51B and the main surface 221 of the third wiring layer 22C. As a result, the second input terminal 51B is electrically connected to the first electrode 11 of each second element 10B via the third conductive component 623, the third metal component 30C (third wiring layer 22C), and the plurality of second wires 612. Figure 3 As shown, the third conductive member 623 is formed of, for example, a plurality of bonding wires. The bonding wires are made of, for example, a metal containing aluminum, a metal containing copper, or a metal containing gold.

[0094] like Figure 3 and Figure 8As shown, the pair of fourth conductive components 624 are bonded to the pad portions 521 of the pair of output terminals 52 and the main surfaces 301 of the pair of second metal components 30B. Thus, the pair of output terminals 52 are electrically connected to the second electrodes 12 of the second elements 10B via the pair of fourth conductive components 624 and the pair of second metal components 30B (a pair of second wiring layers 22B). Furthermore, the pair of output terminals 52 are electrically connected to the first electrodes 11 of the first elements 10A via the pair of fourth conductive components 624, the pair of second metal components 30B (the second wiring layers 22B), and the plurality of first wires 611. Figure 3 As shown, each of the pair of fourth conductive members 624 is formed of, for example, a plurality of bonding wires. The bonding wires are made of, for example, a metal containing aluminum, a metal containing copper, or a metal containing gold.

[0095] Furthermore, the first conductive member 621, the second conductive member 622, the third conductive member 623, and the pair of fourth conductive members 624 may each be a metal wire or a bonding tape instead of a plurality of bonding wires. The metal wire or bonding tape may be made of, for example, a metal containing copper, a metal containing aluminum, or a metal containing gold.

[0096] The sealing member 7 is a semiconductor package of the semiconductor device A1. Figures 1 to 11 As shown, the sealing member 7 covers the various components of the semiconductor device A1. However, the support member 2, the pair of input terminals 51, the pair of output terminals 52, the multiple control terminals 53, and the multiple detection terminals 54 are each partially covered. The constituent material of the sealing member 7 is, for example, epoxy resin. For example, the dimension of the sealing member 7 in the x-direction is greater than 20 mm and less than 120 mm (preferably greater than 25 mm and less than 60 mm), the dimension in the y-direction is greater than 20 mm and less than 120 mm (preferably greater than 40 mm and less than 70 mm), and the dimension in the z-direction is greater than 5 mm and less than 10 mm (preferably 7 mm). The sealing member 7 has a main surface 71, a back surface 72, multiple side surfaces 731 to 734, and a pair of mounting holes 74.

[0097] like Figures 5 to 7 As shown, the main surface 71 and the back surface 72 are separated in the z direction. The main surface 71 faces the z2 direction, and the back surface 72 faces the z1 direction. Figure 4 As shown, the back surface 72 is in a frame shape surrounding the back surface 212 of the insulating substrate 21 when viewed from above. The back surface 212 of the insulating substrate 21 is exposed from the back surface 72. The plurality of side surfaces 731 to 734 are sandwiched by the main surface 71 and the back surface 72 in the z direction and are connected to both. Figure 3 As shown, the side surfaces 731 and 732 are separated in the x direction. The side surface 731 faces the x1 direction, and the side surface 732 faces the x2 direction. Figure 3As shown, the side surfaces 733 and 734 are separated in the y direction, with the side surface 733 facing the y1 direction and the side surface 734 facing the y2 direction.

[0098] like Figure 3 As shown, the terminal portions 512 of the pair of input terminals 51, the terminal portions 532 of the pair of control terminals 53 corresponding to the pair of second elements 10B, and the terminal portions 542 of the pair of detection terminals 54 are exposed from the side surface 731. Figure 3 As shown, the terminal portions 522 of the pair of output terminals 52 , the terminal portions 532 of the pair of control terminals 53 arranged corresponding to the pair of first elements 10A, and the terminal portions 542 of the pair of detection terminals 54 are exposed from the side surface 732 .

[0099] like Figures 5 to 7 and Figure 10 As shown, a pair of mounting holes 74 are connected from the main surface 71 to the back surface 72 in the z direction and pass through the sealing member 7. Figures 2 to 4 As shown, the pair of mounting holes 74 are each, for example, circular in plan view. The pair of mounting holes 74 are located on opposite sides of the insulating substrate 21 in the y direction. The separation distance between the pair of mounting holes 74 in the y direction is, for example, 15 mm to 100 mm (preferably 30 mm to 70 mm). The pair of mounting holes 74 can be used when mounting the semiconductor device A1 on a heat sink.

[0100] The semiconductor device A1 configured as described above has the following effects.

[0101] According to the semiconductor device A1, there are a semiconductor element 10, a support component 2, and a metal component 30. The semiconductor element 10 is bonded to the metal component 30 via a first bonding layer 41, and the metal component 30 is bonded to the support component 2 via a second bonding layer 42. Each metal component 30 includes a first metal body 31 made of a first metal material and a second metal body 32 made of a second metal material, and has a boundary (equivalent to an interface 33) between the first metal body 31 and the second metal body 32. Moreover, the linear expansion coefficient of the second metal material is smaller than the linear expansion coefficient of the first metal material. According to this structure, when the metal component 30 thermally expands due to heat from the semiconductor element 10, thermal deformation occurs near the boundary between the first metal body 31 and the second metal body 32, and the thermal stress near the boundary is locally relieved. Thus, compared to the case where the metal component 30 is made only of the first metal material, the thermal stress caused by the thermal expansion of the metal component 30 can be relieved. As a result, for example, the thermal stress applied to the second bonding layer 42 connected to the metal component 30 can be relieved, suppressing cohesive failure of the second bonding layer 42. In other words, semiconductor device A1 can improve reliability by suppressing product failures such as poor bonding and poor conduction. Furthermore, semiconductor device A1 can mitigate thermal stress applied to first bonding layer 41 in contact with metal component 30, thereby suppressing cohesive failure of first bonding layer 41.

[0102] According to the semiconductor device A1, the thickness of each metal component 30 is greater than the thickness of the support component 2, and is greater than 0.5 mm and less than 5 mm (preferably less than 1.0 mm and greater than 3 mm). For example, in a semiconductor device different from the semiconductor device A1 of the present invention, thermal stress can also be alleviated by making the thickness of each metal component smaller than the thickness of the metal component 30 and reducing the rigidity of the metal component. However, in such a method (a method of thinning the metal component), it is possible that the metal component will warp, the sealing component 7 will enter between the metal component and the support component, and the support component 2 will be damaged (cracked). In addition, in the method of thinning the metal component, the thermal diffusion efficiency of the metal component may be reduced. On the other hand, in the semiconductor device A1, by using the metal component 30 containing the first metal body 31 and the second metal body 32, the thermal stress of the metal component 30 is alleviated as described above. Thus, the semiconductor device A1 can alleviate the thermal stress applied to the second bonding layer 42 while suppressing the damage of the support component 2 and the reduction of the thermal diffusion efficiency.

[0103] According to semiconductor device A1, in each metal component 30, the first metal body 31 includes multiple first metal layers 311, and the second metal body 32 includes multiple second metal layers 321. The multiple first metal layers 311 and the multiple second metal layers 321 are alternately stacked in the z-direction. Thus, each metal component 30 has a stacked structure of multiple first metal layers 311 and multiple second metal layers 321. This structure allows each metal component 30 to have higher thermal conductivity in the z-direction than when it is composed of an alloy (solid solution) of the first metal material and the second metal material.

[0104] In semiconductor device A1, the thickness (dimension in the z-direction) of each second metal layer 321 is smaller than the thickness (dimension in the z-direction) of each first metal layer 311. Since the thermal conductivity of the second metal material is lower than that of the first metal material, the heat diffusion efficiency is reduced compared to a case where each metal component 30 is composed solely of the first metal material. Therefore, in semiconductor device A1, by making each second metal layer 321 having a lower thermal conductivity thinner, it is possible to suppress a reduction in heat diffusion efficiency compared to a case where each first metal layer 311 and each second metal layer 321 have the same thickness.

[0105] According to the semiconductor device A1, each metal component 30 has a crack 34 formed at the interface 33 between the first metal layer 311 and the second metal layer 321. The crack 34 is a local peeling at the interface 33. According to this structure, the thermal stress of the metal component 30 can be relieved in the portion of the crack 34 between the first metal layer 311 and the second metal layer 321. Therefore, the semiconductor device A1 can improve the reliability with respect to thermal stress. In addition, the sealing component 7 is filled in the crack 34, so that the adhesion between each metal component 30 and the sealing component 7 can be improved by the anchor effect. Therefore, the semiconductor device A1 can achieve the relaxation of thermal stress while improving the adhesion of the sealing component 7.

[0106] According to the semiconductor device A1, in each metal component 30, the plurality of first metal layers 311 include a surface layer on the main surface 301 side and a surface layer on the back surface 302 side. That is, each surface in the z direction of each metal component 30 is the first metal layer 311. According to this structure, the initial thermal diffusivity of the semiconductor element 10 can be improved. In addition, the adhesion of the first bonding layer 41 and the second bonding layer 42 of each second metal layer 321 is lower than that of each first metal layer 311. Therefore, by setting each surface in the z direction of each metal component 30 as the first metal layer 311, the adhesion of the first bonding layer 41 and the second bonding layer 42 to each metal component 30 can be improved.

[0107] According to semiconductor device A1, each metal component 30 includes a first metal body 31 formed of a first metal material and a second metal body 32 formed of a second metal material. Furthermore, in each metal component 30, the linear expansion coefficient of the second metal material is closer to that of the insulating substrate 21 than the linear expansion coefficient of the first metal material. This structure allows each metal component 30 to have a linear expansion coefficient closer to that of the insulating substrate 21 than would be the case if each metal component 30 were formed solely of the first metal material. This reduces the difference between the linear expansion coefficient of each metal component 30 and that of the insulating substrate 21, thereby mitigating thermal stress applied to the second bonding layer 42.

[0108] According to the semiconductor device A1, the supporting component 2 includes an insulating substrate 21. The insulating substrate 21 is made of ceramic with excellent thermal conductivity. According to this structure, the heat generated by the semiconductor element 10 is diffused by the metal component 30 and transferred to the insulating substrate 21. Therefore, the semiconductor device A1 can improve the heat dissipation efficiency of the semiconductor element 10 because the heat from the semiconductor element 10 is diffused to the metal component 30 and the insulating substrate 21. Furthermore, the back surface 212 of the insulating substrate 21 is exposed from the sealing component 7. According to this structure, the heat transferred to the insulating substrate 21 is emitted to the outside from the back surface 212. In addition, when the semiconductor device A1 is equipped with a heat sink, the heat is transferred from the back surface 212 to the heat sink. Therefore, the semiconductor device A1 can efficiently dissipate the heat from the semiconductor element 10.

[0109] Figure 15 A semiconductor device A2 according to a second embodiment is shown. Figure 15 FIG2 is a top view of semiconductor device A2, with sealing member 7 indicated by an imaginary line (two-dot chain line). Compared to semiconductor device A1, semiconductor device A2 differs primarily in the structure of the plurality of wiring layers 22 of support member 2. Consequently, the arrangement of the plurality of semiconductor elements 10, the plurality of metal members 30, the pair of input terminals 51, the pair of output terminals 52, the plurality of control terminals 53, the plurality of detection terminals 54, and the plurality of connecting members 6 also differs.

[0110] like Figure 15 As shown, the plurality of wiring layers 22 of the support member 2 include a first wiring layer 22A, a pair of second wiring layers 22B, a third wiring layer 22C, and a fourth wiring layer 22D. Thus, unlike the semiconductor device A1, the semiconductor device A2 has only one first wiring layer 22A and also includes a fourth wiring layer 22D.

[0111] The first wiring layer 22A is located on the x2 and y2 sides of the insulating substrate 21. A pair of second wiring layers 22B are located on the x1 and y1 sides of the insulating substrate 21. The pair of second wiring layers 22B are adjacent in the y direction. The third wiring layer 22C is located on the x2 and y1 sides. The third wiring layer 22C is located next to the first wiring layer 22A in the y direction. The third wiring layer 22C and the first wiring layer 22A have substantially the same shape. The fourth wiring layer 22D is located on the x1 and y2 sides. The fourth wiring layer 22D is located next to the first wiring layer 22A in the x direction. The fourth wiring layer 22D has substantially the same shape as one of the pair of second wiring layers 22B.

[0112] like Figure 15 As shown, the plurality of metal components 30 include a first metal component 30A, a pair of second metal components 30B, a third metal component 30C, and a fourth metal component 30D. Thus, unlike semiconductor device A1, semiconductor device A2 has only one first metal component 30A and further includes a fourth metal component 30D.

[0113] The first metal member 30A is bonded to the first wiring layer 22A via the second bonding layer 42. The two first elements 10A are bonded to the first metal member 30A via the first bonding layer 41. Thus, in this embodiment, two semiconductor elements 10 (first elements 10A) are bonded to one metal member 30 (first metal member 30A).

[0114] The pair of second metal members 30B are respectively bonded to the pair of second elements 10B via the first bonding layer 41 as in the first embodiment. The fourth metal member 30D is not bonded to any of the plurality of semiconductor elements 10. The fourth metal member 30D is bonded to the plurality of first wires 611 and the first conductive member 621.

[0115] In the semiconductor device A2 , the first conductive member 621 is joined to the fourth metal member 30D and one of the pair of second metal members 30B to provide electrical connection between them.

[0116] In the semiconductor device A2, as Figure 15 As shown, the pair of input terminals 51 are located on the x2 side. In addition, the pair of input terminals 51 are separated in the y direction, with the first input terminal 51A located in the y2 direction and the second input terminal 51B located in the y1 direction.

[0117] In semiconductor device A2, first input terminal 51A is electrically connected to second electrode 12 of each first element 10A via second conductive member 622 and first metal member 30A. Second input terminal 51B is electrically connected to first electrode 11 of each second element 10B via third conductive member 623, third metal member 30C, and a plurality of second wires 612.

[0118] In the semiconductor device A2, as Figure 15 As shown, the pair of output terminals 52 are located on the x1 side. In semiconductor device A2, the output terminal 52 on the y1 side is electrically connected to the second electrode 12 of one of the pair of second elements 10B via the fourth conductive component 624 and the second metal component 30B, and is electrically connected to the first electrode 11 of one of the pair of first elements 10A via the fourth conductive component 624, the second metal component 30B, the first conductive component 621, the fourth metal component 30D, and the plurality of first wires 611. Furthermore, the output terminal 52 on the y2 side is electrically connected to the second electrode 12 of the other of the pair of second elements 10B via the fourth conductive component 624 and the second metal component 30B, and is electrically connected to the first electrode 11 of the other of the pair of first elements 10A via the fourth conductive component 624, the second metal component 30B, and the plurality of first wires 611.

[0119] Semiconductor device A2 includes a control terminal 53 that partially protrudes from side surface 731 and a control terminal 53 that partially protrudes from side surface 732. The control terminal 53 that partially protrudes from side surface 731 is electrically connected to the third electrode 13 of each first element 10A via a plurality of third wires 613. Furthermore, the control terminal 53 that partially protrudes from side surface 732 is electrically connected to the third electrode 13 of each second element 10B via a plurality of third wires 613. This embodiment shows a case where two control terminals 53 are provided, one common to a pair of first elements 10A and the other common to a pair of second elements 10B, but the present invention is not limited thereto. For example, similar to semiconductor device A1, four control terminals 53 may be provided, each corresponding to a plurality of semiconductor elements 10 (a pair of first elements 10A and a pair of second elements 10B).

[0120] Semiconductor device A2 includes a detection terminal 54 that partially protrudes from side surface 731 and a detection terminal 54 that partially protrudes from side surface 732. The detection terminal 54 that partially protrudes from side surface 732 is electrically connected to the first electrode 11 of either of the pair of first elements 10A via a fourth line 614. Furthermore, the detection terminal 54 that partially protrudes from side surface 731 is electrically connected to the first electrode 11 of either of the pair of second elements 10B via a fourth line 614. This embodiment illustrates a case where two detection terminals 54 are provided, with one detection terminal 54 electrically connected to either of the pair of first elements 10A and the other detection terminal 54 electrically connected to either of the pair of second elements 10B. However, the present invention is not limited thereto. For example, similar to semiconductor device A1, four detection terminals 54 may be provided, each corresponding to a plurality of semiconductor elements 10 (a pair of first elements 10A and a pair of second elements 10B).

[0121] The semiconductor device A2 configured as described above has the following effects.

[0122] According to the semiconductor device A2, there is a semiconductor element 10, a support part 2 and a metal part 30. The semiconductor element 10 is bonded to the metal part 30 through a first bonding layer 41, and the metal part 30 is bonded to the support part 2 through a second bonding layer 42. The metal part 30 includes a first metal body 31 and a second metal body 32, and has a boundary between the first metal body 31 and the second metal body 32 (equivalent to an interface 33). The first metal body 31 is made of a first metal material, and the second metal body 32 is made of a second metal material, and the linear expansion coefficient of the second metal material is smaller than the linear expansion coefficient of the first metal material. Thus, the semiconductor device A2, like the semiconductor device A1, can alleviate the thermal stress applied to the second bonding layer 42 connected to the metal part 30, thereby suppressing the cohesive failure of the second bonding layer 42. That is, the semiconductor device A2 can improve reliability because it can suppress the occurrence of product failures such as poor bonding and poor conduction.

[0123] According to the semiconductor device A2, except for this, the same or similar structure as that of the semiconductor device A1 can produce the same effects as those of the semiconductor device A1.

[0124] While the first and second embodiments illustrate the case where each metal component 30 is bonded to each wiring layer 22 via the second bonding layer 42, the present invention is not limited thereto. For example, each metal component 30 may be bonded to the insulating substrate 21 via the second bonding layer 42. In other words, the support component 2 may not include multiple wiring layers 22. In this case, thermal stress applied to the second bonding layer 42 in contact with the metal component 30 can also be mitigated.

[0125] In the first and second embodiments, the first input terminal 51A is shown as being electrically conductive with the first metal member 30A via the second conductive member 622. However, the first input terminal 51A may be directly bonded to the first metal member 30A to achieve electrical conduction therebetween. Similarly, although the second input terminal 51B is shown as being electrically conductive with the third metal member 30C via the third conductive member 623, electrical conduction therebetween may also be achieved by directly bonding the second input terminal 51B to the third metal member 30C. Furthermore, although the output terminals 52 are shown as being electrically conductive with the second metal member 30B via the fourth conductive member 624, electrical conduction therebetween may also be achieved by directly bonding the output terminals 52 to the third metal member 30B.

[0126] Figure 16 and Figure 17 A semiconductor device A3 according to a third embodiment is shown. Figure 16 1 is a plan view showing the semiconductor device A3 , in which the sealing member 7 is indicated by an imaginary line (two-dot chain line). Figure 17 It is along Figure 16 The semiconductor device A3 is a so-called TO (Transistor Outline) package type.

[0127] The support member 2 is a so-called lead frame. The constituent material of the support member 2 is, for example, copper or a copper alloy. Figure 16 and Figure 17 As shown, the support member 2 includes a die pad portion 251 , a plurality of inner lead portions 252 , and a plurality of outer lead portions 253 .

[0128] The die pad portion 251 is bonded to a metal component 30, and the semiconductor element 10 is mounted via the metal component 30. Figure 16 and Figure 17 As shown in FIG. 1 , a portion of the surface of the die pad portion 251 facing the z1 direction is exposed from the sealing member 7 . Thus, the die pad portion 251 is covered with the sealing member 7 except for this portion of the surface.

[0129] The plurality of inner lead portions 252 are each separated from the die pad portion 251 and covered with the sealing member 7. One end of each connecting member 6 is joined to each inner lead portion 252. The supporting member 2 of the semiconductor device A3 includes two inner lead portions 252.

[0130] The outer leads 253 are connected to any of the inner leads 252 and are exposed from the sealing member 7. The outer leads 253 are terminals of the semiconductor device A3 and can be bonded to a wiring board of an electric appliance or the like.

[0131] The plurality of connecting components 6 are respectively bonding wires. In addition, each connecting component 6 may also be replaced by a metal lead, a bonding tape, etc. Figure 16 As shown in FIG. 1 , the semiconductor device A3 includes two connecting components 6. The number of connecting components 6 is not particularly limited. Figure 16 As shown, one side of the two connecting members 6 is bonded to the third electrode 13 of the semiconductor element 10 and one side of the two inner leads 252, thereby providing electrical continuity therebetween. The other side of the two connecting members 6 is bonded to the first electrode 11 of the semiconductor element 10 and the other side of the two inner leads 252, thereby providing electrical continuity therebetween.

[0132] The semiconductor device A3 constructed as described above has the following effects.

[0133] According to the semiconductor device A3, there is a semiconductor element 10, a support part 2 and a metal part 30. The semiconductor element 10 is bonded to the metal part 30 through a first bonding layer 41, and the metal part 30 is bonded to the support part 2 through a second bonding layer 42. The metal part 30 includes a first metal body 31 and a second metal body 32, and has a boundary between the first metal body 31 and the second metal body 32 (equivalent to an interface 33). The first metal body 31 is made of a first metal material, and the second metal body 32 is made of a second metal material, and the linear expansion coefficient of the second metal material is smaller than the linear expansion coefficient of the first metal material. Thus, the semiconductor device A3 can alleviate the thermal stress applied to the second bonding layer 42 connected to the metal part 30 in the same way as the semiconductor device A1, thereby suppressing the cohesive failure of the second bonding layer 42. That is, the semiconductor device A3 can improve reliability because it can suppress the occurrence of product failures such as poor bonding and poor conduction.

[0134] According to the semiconductor device A3, except for this, the same or similar structure as that of the semiconductor device A1 (A2) can produce the same effects as those of the semiconductor device A1 (A2).

[0135] In the third embodiment, the semiconductor device A3 is a so-called TO package type. However, the present invention is not limited thereto and can be applied to various types of semiconductor packages such as SOP (Small Outline Package), Non-Lead package, or BGA (Ball Grid Array) package.

[0136] In the third embodiment, the supporting member 2 is a lead frame, but the supporting member 2 is not limited thereto and may be an intermediate layer, a printed circuit board, a DBC (Direct Bonded Copper) board, a DBA (Direct Bonded Aluminum) board, or the like.

[0137] Figure 18 Modifications of the metal member 30 are shown. Figure 18 is a cross-sectional view of a metal component 30 of a modified example, corresponding to the semiconductor device A1. Figure 13 . Figure 18 The metal member 30 shown can be used as a substitute for the metal members 30 of the semiconductor devices A1 to A3 .

[0138] like Figure 18 As shown, in the metal component 30 of the modified example, the second metal body 32 is a porous body having a plurality of pores, and the plurality of pores are filled with the first metal body 31. Therefore, the metal component 30 of the modified example is a composite material different from the laminated structure. The content of the second metal body 32 in each metal component 30 is 10% or more and 40% or less (preferably 30%). Figure 18In the example shown, all of the multiple pores are not shown. Figure 18 Since the portions of the second metal body 32 are connected to the outside of the second metal body 32, all of the plurality of pores are filled with the first metal body 31. Furthermore, rather than filling all of the pores of the second metal body 32 with the first metal body 31, a mixture of pores filled with the first metal body 31 and pores filled with air may exist. For example, if the second metal body 32 has pores that are not connected to the outside of the second metal body 32, the pores are filled with the first metal body 31.

[0139] The metal component 30 of this modification is formed, for example, as follows. First, a second metal body 32 having a plurality of pores is prepared. In this case, each pore is an air hole. In addition, the pore occupancy rate in the second metal body 32 is greater than 10% and less than 70% (preferably 30%). Then, utilizing the property that the melting point of the first metal material is lower than that of the second metal material, the solid phase second metal body 32 is immersed in the liquid phase first metal body 31. As a result, the metal component 30 has a structure in which the plurality of pores in the second metal body 32 are filled with the first metal body 31.

[0140] In use Figure 18 In the case of the metal component 30 shown, the heat generated by the semiconductor element 10 causes thermal deformation of the metal component 30 near the boundary between the first metal body 31 and the second metal body 32, thereby alleviating the thermal stress near the boundary. As a result, the thermal stress caused by the thermal expansion of each metal component 30 can be alleviated, and thus the thermal stress applied to the second bonding layer 42 connected to the metal component 30 can be alleviated, and the cohesive failure of the second bonding layer 42 can be suppressed. Figure 18 In the semiconductor device including the metal member 30 shown, the occurrence of product failures such as poor bonding and poor conduction can be suppressed, thereby improving reliability.

[0141] The semiconductor device disclosed herein is not limited to the above-described embodiment, and the specific structure of each component of the semiconductor device disclosed herein can be arbitrarily modified in various designs.

[0142] The semiconductor device of the present invention includes the embodiments described in the following notes.

[0143] [Note 1]

[0144] A semiconductor device comprising:

[0145] Support components;

[0146] a metal member having a first main surface and a first back surface separated in a thickness direction, the first back surface facing the support member and bonded to the support member;

[0147] a bonding layer bonding the support member and the metal member;

[0148] a semiconductor element facing the first main surface and bonded to the metal member; and

[0149] a sealing member covering the support member, the metal member, the bonding layer, and the semiconductor element;

[0150] The metal component includes a first metal body made of a first metal material and a second metal body made of a second metal material, and has a boundary between the first metal body and the second metal body.

[0151] The second metal material has a smaller linear expansion coefficient than the first metal material.

[0152] [Note 2]

[0153] The semiconductor device according to note 1, wherein

[0154] The first metal body includes a plurality of first metal layers.

[0155] The second metal body includes a plurality of second metal layers.

[0156] The metal member forms a stacked structure in which the plurality of first metal layers and the plurality of second metal layers are alternately stacked in the thickness direction.

[0157] [Note 3]

[0158] The semiconductor device according to note 2, wherein:

[0159] The plurality of first metal layers include a surface layer on the first main surface side and a surface layer on the first rear surface side of the metal member.

[0160] [Note 4]

[0161] The semiconductor device according to note 2 or 3, wherein

[0162] The thickness of each of the plurality of first metal layers is greater than the thickness of each of the plurality of second metal layers.

[0163] [Note 5]

[0164] The semiconductor device according to any one of notes 2 to 3, wherein

[0165] The metal member has a side surface sandwiched by the first main surface and the first rear surface and connected to the first main surface and the first rear surface, and a crack extending from the side surface toward the inside of the metal member is formed.

[0166] [Note 6]

[0167] The semiconductor device according to note 5, wherein

[0168] The crack is formed by partial peeling of the first metal layer and the second metal layer that are connected to each other.

[0169] [Note 7]

[0170] The semiconductor device according to note 5 or 6, wherein

[0171] The crack is filled with the sealing member.

[0172] [Note 8]

[0173] The semiconductor device according to any one of notes 1 to 7, wherein

[0174] The first metal material includes copper.

[0175] [Note 9]

[0176] The semiconductor device according to any one of notes 1 to 8, wherein

[0177] The second metal material includes molybdenum.

[0178] [Note 10]

[0179] The semiconductor device according to any one of notes 1 to 9, wherein

[0180] The supporting member includes an insulating substrate,

[0181] The insulating substrate includes a second main surface and a second back surface separated from each other in the thickness direction, and the second main surface faces the metal member.

[0182] [Note 11]

[0183] The semiconductor device according to note 10, wherein

[0184] The above-mentioned supporting component also includes a wiring layer,

[0185] The wiring layer has a third main surface and a third back surface separated in the thickness direction, and the third back surface is bonded to the insulating substrate.

[0186] The first rear surface of the metal member faces the third main surface and is bonded to the wiring layer.

[0187] [Note 12]

[0188] The semiconductor device according to note 10 or 11, wherein

[0189] The linear expansion coefficient of the second metal material is closer to the linear expansion coefficient of the insulating substrate than the linear expansion coefficient of the first metal material.

[0190] [Note 13]

[0191] The semiconductor device according to any one of notes 10 to 12, wherein

[0192] The insulating substrate is made of ceramic.

[0193] [Note 14]

[0194] The semiconductor device according to any one of notes 10 to 13, wherein

[0195] The back surface of the insulating substrate is exposed from the sealing member.

[0196] [Note 15]

[0197] The semiconductor device according to any one of notes 1 to 14, wherein

[0198] The bonding layer is solder.

[0199] [Note 16]

[0200] The semiconductor device according to any one of notes 1 to 15, wherein

[0201] The semiconductor element is bonded to the metal member via a conductive bonding material.

[0202] [Note 17]

[0203] The semiconductor device according to any one of notes 1 to 16, wherein

[0204] The thickness of the metal member is greater than the thickness of the support member.

[0205] [Note 18]

[0206] The semiconductor device according to any one of notes 1 to 17, wherein the thickness of the metal member is 0.5 mm to 5 mm.

Claims

1. A semiconductor device, characterized in that: have: Support components; a metal member having a first main surface and a first back surface separated in a thickness direction, the first back surface facing the support member and bonded to the support member; a bonding layer bonding the support member and the metal member; a semiconductor element facing the first main surface and bonded to the metal member; and a sealing member covering the support member, the metal member, the bonding layer, and the semiconductor element; The metal component includes a first metal body made of a first metal material and a second metal body made of a second metal material, and has a boundary between the first metal body and the second metal body. The linear expansion coefficient of the second metal material is smaller than the linear expansion coefficient of the first metal material. The first metal body includes a plurality of first metal layers. The second metal body includes a plurality of second metal layers. The metal component forms a stacked structure in which the plurality of first metal layers and the plurality of second metal layers are alternately stacked in the thickness direction. The metal member has a side surface sandwiched by the first main surface and the first rear surface and connected to the first main surface and the first rear surface, and a crack extending from the side surface toward the inside of the metal member is formed.

2. The semiconductor device according to claim 1, wherein The plurality of first metal layers include a surface layer on the first main surface side and a surface layer on the first rear surface side of the metal member.

3. The semiconductor device according to claim 1, wherein The thickness of each of the plurality of first metal layers is greater than the thickness of each of the plurality of second metal layers.

4. The semiconductor device according to claim 1, wherein The crack is formed by partial peeling of the first metal layer and the second metal layer that are connected to each other.

5. The semiconductor device according to claim 1, wherein The crack is filled with the sealing member.

6. The semiconductor device according to claim 1, wherein The first metal material includes copper.

7. The semiconductor device according to claim 1, wherein The second metal material includes molybdenum.

8. The semiconductor device according to any one of claims 1 to 7, wherein The supporting member includes an insulating substrate, The insulating substrate includes a second main surface and a second back surface separated from each other in the thickness direction, and the second main surface faces the metal member.

9. The semiconductor device according to claim 8, wherein The above-mentioned supporting component also includes a wiring layer, The wiring layer has a third main surface and a third back surface separated in the thickness direction, and the third back surface is bonded to the insulating substrate. The first rear surface of the metal member faces the third main surface and is bonded to the wiring layer.

10. The semiconductor device according to claim 8, wherein The linear expansion coefficient of the second metal material is closer to the linear expansion coefficient of the insulating substrate than the linear expansion coefficient of the first metal material.

11. The semiconductor device according to claim 8, wherein The insulating substrate is made of ceramic.

12. The semiconductor device according to claim 8, wherein The back surface of the insulating substrate is exposed from the sealing member.

13. The semiconductor device according to any one of claims 1 to 7, wherein The bonding layer is solder.

14. The semiconductor device according to any one of claims 1 to 7, wherein The semiconductor element is bonded to the metal member via a conductive bonding material.

15. The semiconductor device according to any one of claims 1 to 7, wherein The thickness of the metal member is greater than the thickness of the support member.

16. The semiconductor device according to any one of claims 1 to 7, wherein The thickness of the metal member is not less than 0.5 mm and not more than 5 mm.

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