Connection structure, semiconductor device, and insulated substrate

Abstract

The goal is to create a connection structure that allows for the connection of components with different physical properties, such as coefficients of thermal expansion, at room temperature with high thermal conductivity, while also enabling deformation and stress relief due to the heat generated by the heat source. [Solution] A first member 10 and a second member 20, which is positioned opposite the first member 10 and is made of a material with a different coefficient of thermal expansion than the first member 10, are connected by a connecting member 30. The connecting member 30 has a high heat-resistant resin material 31, a carbon material 32 made of carbon atoms, and a void layer 33. The first member 10 and the second member 20 are thermally connected via the carbon material 32 of the connecting member 30 by being pressed from one to the other by a pressurizing member 80.

Description

Technical Field

[0001] The present invention relates to a connection structure in which a plurality of members having different linear expansion coefficients are connected by a connection member having a carbon material made of carbon atoms, a semiconductor device to which this is applied, and a substrate with built-in insulation.

Background Art

[0002] Conventionally, there is known a connection structure in which members having different linear expansion coefficients and elastic moduli, such as a metal member and a resin member, are connected to each other, and at least one member abuts on another heat generating body to enable heat dissipation. This type of connection structure is required to be connected at a low temperature or normal temperature in order to reduce the influence of warpage and steps, to connect members having different linear expansion coefficients and the like with high thermal conductivity, and to reduce the influence of deformation and stress due to heat. Examples of connection members for connecting members having different linear expansion coefficients and the like include joining members such as solder and heat dissipation grease.

[0003] However, when using solder, although members with different linear expansion coefficients can be connected with high thermal conductivity, they cannot be connected at low temperature or normal temperature, and it is difficult to relieve warpage and stress between the connected members. Also, in the case of heat dissipation grease, although members with different linear expansion coefficients can be connected at low temperature or normal temperature, the members with different linear expansion coefficients are not connected with high thermal conductivity, and it is difficult to relieve warpage and stress between the connected members.

[0004] In the connection structure described in Patent Document 1, a connection member made of a thermoplastic resin material and a carbon-based material such as graphite having high thermal conductivity is used, and members with different linear expansion coefficients are connected with high thermal conductivity at a low temperature or normal temperature.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

[0006] However, in the connection structure described in Patent Document 1, since part of the connecting member is made of thermoplastic resin material, it softens due to the heat from the heating element, making it difficult to relieve deformation such as warping and stress between the different connected members.

[0007] Examples of this type of connection structure include semiconductor devices in which the outer surface of a semiconductor module, in which semiconductor elements are encapsulated in resin, and a cooling body are connected by a connecting member. Other examples include insulating substrates in which a conductive layer constituting circuit wiring, etc., made of a metal material, and an insulating substrate made of an insulating material are connected by a connecting member. An insulating substrate, as used here, refers to a substrate in which a conductive layer is connected to one or both sides of an insulating substrate.

[0008] In view of the above, the present invention aims to provide a connection structure, a semiconductor device, and an insulating substrate that can connect members with different physical properties, such as coefficients of linear expansion, at low temperatures or room temperatures with high thermal conductivity, and that can also relieve deformation and stress caused by the heat of a heating element. [Means for solving the problem]

[0009] To achieve the above objective, the connection structure described in claim 1 comprises a first member (10), a second member (20) positioned opposite the first member and made of a material with a different coefficient of thermal expansion than the first member, a high heat-resistant resin material (31), a carbon material (32) made of carbon atoms, and a void layer (33), and a connecting member (30) that connects the first member and the second member, and pressurizing members (80, 90) that press the connecting member against the other of the first member and the second member via one of the first member and the second member, wherein one end of the carbon material is in contact with the first member and the other end opposite to the one end is in contact with the second member. Furthermore, the connection structure described in claim 2 comprises a first member (10), a second member (20) positioned opposite the first member and made of a material with a different coefficient of thermal expansion than the first member, a high heat-resistant resin material (31), a carbon material (32) made of carbon atoms, and a void layer (33), and includes a connecting member (30) that connects the first member and the second member, a third member (40) that surrounds the outer periphery of the first member and is positioned opposite the second member, and a frame-shaped sealing material (50) that surrounds the outer periphery of the connecting member and connects the second member and the third member, wherein one end of the carbon material is in contact with the first member and the other end opposite to the one end is in contact with the second member.

[0010] According to this, a connecting structure is formed in which the first member and the second member are thermally connected by a connecting member having a high heat-resistant resin material, a carbon material, and a void layer. In this connecting structure, the first member and the second member are connected with high thermal conductivity at room temperature by a carbon material with high thermal conductivity, and because the resin material among the connecting materials is a high heat-resistant resin material, it does not soften due to heat, thus allowing for deformation and stress relief of the heating element due to heat.

[0011] The semiconductor device according to claim 10 comprises a semiconductor module (10) having a semiconductor element (140) and a heat sink (130) thermally connected to the semiconductor element; a heat sink (20) positioned opposite the heat sink within the semiconductor module; a heat sink (30) connecting the semiconductor element and the heat sink, comprising a high heat-resistant resin material (31), a carbon material (32) composed of carbon atoms, and a void layer (33); and pressurizing members (80, 90) pressing the connecting member against the other of the heat sink and the heat sink via one of the heat sink and the heat sink, wherein one end of the carbon material is in contact with the heat sink and the other end opposite to the one end is in contact with the heat sink.

[0012] According to this, the semiconductor device is one in which a semiconductor module and a heat sink are thermally connected by a connecting member having a high heat-resistant resin material, a carbon material, and a void layer. The semiconductor module and the heat sink are thermally connected by the carbon material, which has high thermal conductivity, and the resin material is a high heat-resistant resin material, so the connecting member does not soften due to heat. As a result, the semiconductor module and the heat sink are connected with high thermal conductivity at room temperature, and the semiconductor device is capable of relieving thermal deformation and stress on the semiconductor element, which is the heat-generating element.

[0013] The insulating substrate according to claim 11 comprises a conductive layer (10) made of a conductive material, an insulating substrate (20) made of an insulating material and positioned opposite the conductive layer, a high heat-resistant resin material (31), a carbon material (32) made of carbon atoms, and a void layer (33), and further comprises a connecting member (30) connecting the conductive layer and the insulating substrate, a third member (40) surrounding the outer periphery of the conductive layer and positioned opposite the insulating substrate, and a frame-shaped sealing material (50) surrounding the outer periphery of the connecting member and connecting the insulating substrate and the third member, wherein one end of the carbon material is in contact with the conductive layer and the other end opposite to the one end is in contact with the insulating substrate.

[0014] According to this, the conductive layer and the insulating substrate are thermally connected by a connecting member comprising a high heat-resistant resin material, a carbon material, and a void layer. The conductive layer and the insulating substrate are thermally connected by the carbon material, which has high thermal conductivity, and the resin material is a high heat-resistant resin material, so the connecting member does not soften due to heat. As a result, the conductive layer and the insulating substrate are connected with high thermal conductivity at room temperature, and the insulating substrate is less susceptible to deformation and stress caused by the heat of other heat-generating elements.

[0015] The reference numerals in parentheses attached to each component indicate an example of the correspondence between that component and the specific components described in the embodiments described later. [Brief explanation of the drawing]

[0016] [Figure 1] This is a cross-sectional view showing the connection structure of the first embodiment. [Figure 2] It is a figure showing the result of observing the cross section of the connection structure of the first embodiment with a scanning electron microscope (SEM). [Figure 3] It is a figure showing the result of observing the cross section of the connection member before being used for connecting members with SEM. [Figure 4] It is a figure showing the relationship among the pressure when pressurizing the connection member, the thermal resistance of the connection structure, and the inclination angle of the carbon material. [Figure 5] It is a figure showing the result of observing the cross section of the connection structure under a pressure of 1 MPa with SEM. [Figure 6] It is a figure showing the result of observing the cross section of the connection structure under a pressure of 2 MPa with SEM. [Figure 7] It is a figure showing the result of observing the cross section of the connection structure under a pressure of 12.5 MPa with SEM. [Figure 8] It is a figure corresponding to Figure 3 and showing the result of observing the cross section of the connection member in which the carbon material is natural graphite with SEM. [Figure 9] It is a figure corresponding to Figure 2 and showing the result of observing the cross section of the connection structure using the connection member in which the carbon material is natural graphite with SEM. [Figure 10] It is a figure showing the relationship among the pressure when pressurizing the connection member in the connection structure shown in Figure 9, the thermal resistance of the connection structure, and the inclination angle of the carbon material. [Figure 11] It is a cross-sectional view showing the connection structure of the second embodiment. [Figure 12] It is an enlarged cross-sectional view showing the XII region of Figure 11. [Figure 13] It is a figure corresponding to Figure 12 and showing an enlarged cross-sectional view showing a modification of the connection structure of the second embodiment. [Figure 14] It is a cross-sectional view showing the connection structure of the third embodiment. [Figure 15] It is an explanatory diagram for explaining the bonding of the first member using an organic film, the carbon material of the connection member, and the second member. [Figure 16] It is a cross-sectional view showing the connection structure of the fourth embodiment. [Figure 17]This is a cross-sectional view showing another example of the arrangement of the sealing material. [Figure 18] This is a cross-sectional view showing a first modified example of the connection structure of the fourth embodiment. [Figure 19] This is a cross-sectional view showing a second modified example of the connection structure of the fourth embodiment. [Figure 20] This is a cross-sectional view showing a third modified example of the connection structure of the fourth embodiment. [Figure 21] This is a cross-sectional view showing a fourth modified example of the connection structure of the fourth embodiment. [Figure 22] This is a cross-sectional view showing the connection structure of the fifth embodiment. [Figure 23] This is a cross-sectional view showing a first modified example of the connection structure of the fifth embodiment. [Figure 24] This is a top layout diagram showing an example of the arrangement of sealing material in a second modified example of the connection structure of the fifth embodiment. [Figure 25] This is a top layout diagram showing another example of the arrangement of the sealing material in a second modification of the fifth embodiment. [Figure 26] This is a top layout diagram showing another example of the arrangement of the sealing material in a second modification of the fifth embodiment. [Figure 27] This is a cross-sectional view showing the connection structure of the sixth embodiment. [Figure 28] This is a cross-sectional view showing a first modified example of the connection structure of the sixth embodiment. [Figure 29] This is a cross-sectional view showing a second modified example of the connection structure of the sixth embodiment. [Figure 30] This is a cross-sectional view showing an example of a semiconductor device using the connection structure according to the embodiment. [Figure 31] This is a cross-sectional view showing an example of an insulated substrate using the connection structure according to the embodiment. [Figure 32] This is an explanatory diagram showing an example of the arrangement relationship between the first member and the connecting member when the first member is a graphite heat sink. [Modes for carrying out the invention]

[0017] The embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be denoted by the same reference numerals.

[0018] (First Embodiment) The first embodiment will be described with reference to the drawings. Figure 1 shows a simplified version of the connecting member 30, which will be described later, for clarity.

[0019] [Connection structure] The connection structure according to this embodiment, as shown in Figure 1 for example, comprises a first member 10, a second member 20, and a connecting member 30 disposed between the first member 10 and the second member 20 to thermally connect them. This connection structure is suitable for, for example, when the first member 10 is connected to another heat source such as an electronic component, and the heat from the heat source is diffused from the first member 10 to the second member 20 via the connecting member 30. In this connection structure, as shown in Figure 2 for example, the carbon material 32 constituting the connecting member 30, described later, is inclined with respect to the thickness direction, and the first member 10 and the second member 20 are connected with high thermal conductivity via the carbon material 32.

[0020] The first member 10 is made of a highly thermally conductive material, such as a metal material, in a portion that contacts the connecting member 30, for example. The first member 10 may be, but is not limited to, a metal plate, an insulating substrate with metal layers bonded to both sides of an insulating substrate, or a semiconductor module in which a semiconductor element is connected to a heat sink and sealed in resin.

[0021] The second member 20 is any member composed of a material that has a different coefficient of thermal expansion and elastic modulus from that of the first member 10. "Different coefficient of thermal expansion and elastic modulus from that of the first member 10" means that, if the first member 10 is a composite member composed of multiple constituent materials, the coefficient of thermal expansion and elastic modulus of the first member 10 as a whole are different. Such cases include, for example, when the first member 10 is a composite member and the part facing the second member 20 is made of the same constituent material as the second member 20, but other parts of the first member 10 have a different coefficient of thermal expansion and elastic modulus from that of the second member 20. The second member 20 is positioned opposite the first member 10 and is thermally connected to the first member 10 via a connecting member 30. The second member 20 may be, but is not limited to, an insulating substrate made of ceramic, a heat sink or cooler made of a metal material with high thermal conductivity such as Al (aluminum) or an alloy thereof. The second member 20 is, for example, larger in planar size than the first member 10, and is positioned so as to enclose the entire area of ​​the first member 10 inside the outer shell.

[0022] The connecting member 30, as shown in Figure 1 for example, comprises a high heat-resistant resin material 31, a carbon material 32, and a void layer 33, and is a member that thermally connects different members 10 and 20 using the carbon material 32. In the connecting member 30, for example, multiple carbon materials 32 are regularly arranged with gaps between them, the high heat-resistant resin material 31 is partially arranged in these gaps, and the remaining part of the gaps forms the void layer 33. The connecting member 30 is placed, for example, between a first member 10 and a second member 20, and when pressurized by members 10 and 20 at room temperature or a low temperature of 150°C or less, the carbon material 32 with high thermal conductivity comes into contact with members 10 and 20, respectively, and is responsible for heat conduction between members 10 and 20. In the state before thermally connecting two different members, as shown in Figure 3 for example, the carbon material 32 is arranged along the thickness direction D1 of the connecting member 30, and the void layer 33 has a wider width than when connected. The connecting member 30 is flexible, and when it thermally connects the first member 10 and the second member 20, the multiple carbon materials 32 are inclined substantially uniformly with respect to the thickness direction D1. The inclination angle of these carbon materials 32 will be described later.

[0023] The connecting member 30 can be obtained, for example, by preparing a graphite sheet in which flake-shaped graphite is arranged regularly, applying the material constituting the high heat-resistant resin material 31 itself or a solution containing said material to the graphite sheet, and then heating the surface to which the solution has been applied under pressure. The graphite sheet can be obtained, for example, by pressurizing powdered or flake-shaped graphite at 1 MPa or more to form a sheet, drying the resulting sheet of graphite by any method such as reduced pressure or natural drying, and then heating it under pressure at 100°C to 400°C and 10 MPa to 40 MPa. In addition to the high heat-resistant resin material 31 and the carbon material 32, the connecting member 30 may also contain other materials such as metal particles or spacers as needed, to the extent that flexibility is not impaired. The connecting member 30 has a thickness of approximately 100 μm to 1 mm when the first member 10 and the second member 20 are thermally connected, but is not limited to this range. Furthermore, the connecting member 30 is not limited to a configuration in which multiple carbon materials 32 are regularly arranged in a predetermined pattern, such as a staggered pattern, but may also be configured in which some or all of the multiple carbon materials 32 are arranged irregularly.

[0024] The high heat-resistant resin material 31 functions as a binder for multiple carbon materials 32 arranged regularly at a distance from each other. The high heat-resistant resin material 31 is a thermosetting resin material, a thermoplastic resin material with a melting point of 200°C or higher, or a combination of these. For example, in the case of a thermosetting resin, the high heat-resistant resin material 31 can be any thermosetting material that is flexible in its cured state, such as flexible epoxy resin, rubber-based resin, urethane-based resin, silicone-based resin, fluororesin, or acrylic resin, but is not limited to these. For example, in the case of a thermoplastic resin, the high heat-resistant resin material 31 can be any thermoplastic material such as polyethylene terephthalate or other polyester with a melting point of 200°C or higher, but is not limited to these. The connecting member 30 is kept flexible while preventing excessive softening when heated, thanks to the high heat-resistant resin material 31 acting as a binder.

[0025] The carbon material 32 is in contact with the first member 10 and the second member 20, respectively, and thermally connects them with a predetermined or higher thermal conductivity. The carbon material 32 is composed of materials made of carbon atoms, such as artificial graphite (thermal conductivity: approximately 1700 W / (m·K)), natural graphite (thermal conductivity: approximately 400-500 W / (m·K)), and carbon nanotubes (theoretical value of thermal conductivity: approximately 6000 W / (m·K)). The carbon material 32 is exposed to the outside at the contact surface of the connecting member 30 with the first member 10 and the contact surface with the second member 20. The carbon material 32 is arranged, for example, along one direction on the contact surface of the connecting member 30 when viewed from the direction normal to the contact surface, and with gaps between it along a direction perpendicular to that direction. For the sake of explanation, the following may refer to one direction on the contact surface of the connecting member 30 as the "alignment direction," and the direction perpendicular to the alignment direction as the "arrangement direction." The carbon material 32 tilts approximately uniformly along the arrangement direction as the connecting member 30 is pressurized between two different members, with one end in contact with the first member 10 and the other end opposite to that end in contact with the second member 20. The thermal conductivity of the connecting member 30 as a whole is approximately 800 W / (m·K) when the carbon material 32 is artificial graphite, and approximately 250 W / (m·K) when the carbon material 32 is natural graphite, but is not limited to these values.

[0026] The void layer 33 is the gap between adjacent carbon materials 32 along the direction of arrangement. The void layer 33 plays a role in ensuring cushioning when the connecting member 30 is pressurized by two different members.

[0027] The above describes the basic configuration of the connection structure according to this embodiment. This connection structure is preferably applied to semiconductor devices in which a semiconductor module and a cooler are connected by a connecting member 30, or to insulating substrates in which a conductive layer or graphite heat sink and a ceramic substrate are connected by a connecting member 30, but of course, it can also be applied to other applications.

[0028] [Inclination angle and thermal resistance of carbon materials] Next, we will explain the relationship between the pressure applied to the connecting member 30 by the first member 10 and the second member 20, the thermal resistance of the resulting connecting structure, and the inclination angle of the carbon material 32.

[0029] For the sake of explanation, as shown in Figures 5 to 7, for example, the direction along the straight line connecting one end of the carbon material 32 that contacts the first member 10 and the other end that contacts the second member 20 will be referred to as the "heat conduction direction D2". The "inclination angle" of the carbon material 32 refers to the angle between the thickness direction D1 of the connecting member 30 and the heat conduction direction D2. The thickness direction D1 can also be said to be the direction along the normal direction to the contact surface 10a of the first member 10 with the connecting member 30, or to the contact surface 20a of the second member 20 with the connecting member 30.

[0030] Through diligent research by the inventors, it was found that, for example as shown in Figure 4, the inclination angle of the carbon material 32 changes depending on the pressure when the connecting member 30 is pressurized at room temperature or at a low temperature of 150°C or less, and that the thermal resistance of the resulting connecting structure changes according to this inclination angle. Specifically, when the pressure was 1 MPa, the inclination angle of the carbon material 32 was 45°, for example as shown in Figure 5. When the pressure was 2 MPa, the inclination angle of the carbon material 32 was 47°, for example as shown in Figure 6. When the pressure was 12.5 MPa, the inclination angle of the carbon material 32 was 69°, for example as shown in Figure 7. Further investigation revealed that the thermal resistance of the connecting structure was small, at 1.6°C / W or less, when the inclination angle of the carbon material 32 was within the range R1 of 14° to 70°, while the thermal resistance exceeded 2.2°C / W when it was outside the range R1. In other words, when the inclination angle of the carbon material 32 is in the range of 14° to 70°, the connecting member 30 ensures good contact between one end of the carbon material 32 and the first member 10, and between the other end and the second member 20, thereby thermally connecting members 10 and 20 with high thermal conductivity.

[0031] Furthermore, if the tilt angle of the carbon material 32 is less than 14°, it is thought that the thermal resistance did not decrease because insufficient pressure resulted in insufficient contact between the carbon material 32 of the connecting member 30 and the first member 10 and the second member 20. Also, if the tilt angle of the carbon material 32 exceeds 70°, it is thought that the thermal resistance did not decrease because excessive pressure caused the carbon material 32 of the connecting member 30 to tilt too much in the direction connecting members 10 and 20, or due to damage to the carbon material 32 itself. In addition, if the tilt angle of the carbon material 32 exceeds 70°, it is also thought that the thermal resistance did not decrease because the proportion of the carbon material 32 that does not contact both ends of the carbon material 32, i.e., the area of ​​non-contact between the carbon material 32 and members 10 and 20 increased.

[0032] Furthermore, the inclination angle of the carbon material 32 can be calculated from the difference between the thickness of the connecting member 30 before and after pressurization. For example, when the thickness of the connecting member 30 before pressurization is 300 μm, the thickness of the carbon material 32 before inclination can be considered to be 300 μm. When the thickness of the connecting member 30 after pressurization is 200 μm, the carbon material 32 with a thickness of 300 μm will collapse without deformation, and the inclination angle at which the height from one end to the other of the carbon material 32 becomes 200 μm can be calculated using trigonometric functions, with θ being the inclination angle. Note that the inclination angles at pressures of 1 MPa, 2 MPa, and 12.5 MPa shown in Figures 5 to 7 matched the values ​​obtained by the calculation method described above.

[0033] Figures 4 to 7 show the case where the connecting member 30 is made of artificial graphite as the carbon material 32 (hereinafter referred to as the "first connecting structure"), but a similar trend was observed when the carbon material 32 is natural graphite. Hereafter, for the sake of simplicity, the connecting structure using the connecting member 30 is made of natural graphite as the carbon material 32 will be referred to as the "second connecting structure".

[0034] In the connecting member 30, the carbon material 32 is natural graphite, and before connecting members 10 and 20, as shown in Figure 8, for example, a state is created within one carbon material 32 that is different from the void layer 33. However, in the second connecting structure, as shown in Figure 9, for example, similar to the first connecting structure, the carbon material 32 is tilted substantially uniformly, and the voids within one carbon material 32 are almost completely closed. Furthermore, in the second connecting structure, the relationship between the pressure when the connecting member 30 is pressurized, the thermal resistance, and the tilt angle of the carbon material 32 showed a similar trend to the first connecting structure. In the second connecting structure, as shown in Figure 10, for example, when the tilt angle of the carbon material 32 is within the range R2 of 14° to 70°, the thermal resistance is small, at 1.6°C / W or less, while when it is outside the range R2, the thermal resistance exceeds 2.2°C / W. These results suggest that even when the material used for the carbon material 32 is changed, by applying pressure to the connecting member 30 so that the tilt angle of the carbon material 32 is within a predetermined range, two members with different physical properties, such as the coefficient of linear expansion, can be connected with high thermal conductivity.

[0035] According to this embodiment, two members 10 and 20 with different physical properties such as coefficient of thermal expansion are thermally connected via the carbon material 32 of a connecting member 30 which has a high heat-resistant resin material 31, a carbon material 32, and a void layer 33. In this connecting structure, the connecting member 30 is pressurized by the two members 10 and 20 at room temperature or a low temperature of 150°C or less, and the members 10 and 20 come into contact with the carbon material 32 and are connected with high conductivity, thus eliminating the need for a process of connecting at high temperatures exceeding 150°C. Furthermore, in this connecting structure, the two members 10 and 20 are thermally connected by the carbon material 32, but the members 10 and 20 are not joined together as with joining materials such as solder, thus mitigating deformation and stress caused by heat from an external heat source. In addition, since the binder between the carbon materials 32 of the connecting member 30 is the high heat-resistant resin material 31, it does not soften excessively due to heat. Therefore, in this connection structure, the first member 10 and the second member 20 are connected with high thermal conductivity at room temperature or low temperature using a carbon material 32 with high thermal conductivity, while the connecting member 30 does not soften due to heat, and deformation and stress caused by the heat of an external heat source can be relieved.

[0036] (1) One end of the carbon material 32 is in contact with the first member 10, and the other end opposite to that end is in contact with the second member 20. As a result, the first member 10 and the second member 20 are thermally connected by the carbon material 32, which has high thermal conductivity, and the thermal resistance of the connection structure can be reduced.

[0037] (2) The connecting member 30 is configured such that the inclination angle of the carbon material 32 is within the range of 14° to 70°, thereby ensuring contact between the carbon material 32 and the first member 10 and the second member 20, and enabling the connection of different members with high thermal conductivity.

[0038] (Second Embodiment) A second embodiment will be described with reference to the drawings. In Figures 12 and 13, the high heat-resistant resin material 31 of the connecting member 30 is omitted for clarity.

[0039] The connection structure of this embodiment differs from the first embodiment in that, as shown in Figure 11, for example, a recess 11 is formed on the contact surface 10a of the first member 10, and a recess 21 is formed on the contact surface 20a of the second member 20. This embodiment will mainly explain this difference.

[0040] In this embodiment, the first member 10 has a plurality of recesses 11 formed on its contact surface 10a, as shown in Figure 12, for example. The recesses 11 are formed to increase the frictional force between the connecting member 30 and the carbon material 32, and to facilitate contact with the carbon material 32. The recesses 11 are made to have a width smaller than the width of a single carbon material 32 and a depth of less than a micrometer by any method such as laser irradiation, grinding, cutting, or other machining. In other words, the contact surface 10a is a roughened surface with a fine uneven structure having a plurality of recesses 11 and protrusions sandwiched between the recesses 11.

[0041] In this embodiment, the second member 20 has a plurality of recesses 21 formed on its contact surface 20a. The recesses 21, like the recesses 11, are formed to increase the frictional force with the carbon material 32, and are made to have the same width and depth as the recesses 11, for example, by any of the methods described above. In other words, the contact surface 20a is a roughened surface with fine irregularities on the order of micrometers, for example, similar to the contact surface 10a.

[0042] The recesses 11 and 21 may each be made larger than the width of the carbon material 32, as shown in Figure 13, for example, and may be groove-shaped into which the ends of the carbon material 32 fit. Even in this case, the carbon material 32 and the first member 10 and the second member 20 are more likely to come into contact under pressure compared to the case where the contact surfaces 10a and 20a are smooth surfaces. The width, depth, arrangement pattern and spacing of the recesses 11 and 21 when they are groove-shaped can be appropriately changed according to the width and arrangement pattern of the carbon material 32. In other words, the contact surfaces 10a and 20a may be roughened surfaces with fine irregularities, or have multiple recesses in a predetermined pattern corresponding to the arrangement of the carbon material 32, as long as the carbon material 32 is not slippery.

[0043] This embodiment also provides a connection structure that offers the same effects as the first embodiment described above. Furthermore, the connection structure of this embodiment also provides the following effects.

[0044] (1) This connection structure is configured such that the first member 10 and the second member 20 are in contact with the carbon material 32 at a lower pressure than in the first embodiment, by providing a recess 11 on the contact surface 10a of the first member 10 and a recess 21 on the contact surface 20a of the second member 20.

[0045] (Third embodiment) A third embodiment will be described with reference to the drawings. In Figure 14, the thicknesses of the organic films 12 and 22, which will be described later, are exaggerated to make the configuration easier to understand.

[0046] The connection structure of this embodiment differs from the first embodiment in that an organic film 12 is interposed between the connecting member 30 and the first member 10, and an organic film 22 is interposed between the connecting member 30 and the second member 20. This embodiment will mainly describe this difference.

[0047] In this embodiment, the first member 10 has an organic film 12 formed on its contact surface 10a. The organic film 12 is composed of an arbitrary organic material that bonds with the constituent material of the first member 10 and the carbon material 32 of the connecting member 30. For example, as shown in Figure 15, the organic film 12 is composed of a triazine compound having a triazine ring, which is used as a silane coupling agent. The constituent material of the organic film 12 shown in Figure 15 is, for example, a functional group where the X group has an amino group at its terminus, or an azi group, and a functional group where the Y group has a silanol group at its terminus. The same applies to the organic film 22. As constituent materials for the organic films 12 and 22, for example, reactivity-imparting compounds described in Japanese Patent Application Publication No. 2020-143007 or triazine compounds described in Japanese Patent Application Publication No. 2021-130839 may be used, but other known triazine compounds may also be used. For example, when the first member 10 is made of a metallic material such as Cu (copper), the organic film 12 is applied to the contact surface 10a, and the amino groups interact with the first member 10 to form a chemical bond. In Figure 14, for convenience, the organic film 12 is shown as a uniform film with a predetermined thickness, but in reality, the organic film 12 is, for example, a single molecular layer, and is configured so as not to hinder the reduction of thermal resistance due to contact between the first member 10 and the carbon material 32. The same applies to the organic film 22, which will be described later.

[0048] In this embodiment, for example, the connecting member 30 has surface treatment applied to both sides facing the members 10 and 20, and is chemically bonded with the organic films 12 and 22. For example, the connecting member 30 has an upper surface on the side where one end 321 facing the first member 10 is exposed, and a lower surface on the side where the other end 322 facing the second member 20 is exposed, and both the upper and lower surfaces are subjected to an arbitrary surface treatment. Examples of arbitrary surface treatments include, but are not limited to, corona discharge, atmospheric pressure plasma, ozone oxidation, and superheated steam. As a result, one end 321 and the other end 322 of the carbon material 32 have carboxyl groups and oxygen atoms (not shown) introduced to their surfaces, respectively, which chemically bond with the organic films 12 and 22. The carbon material 32 then has a state in which the carboxyl groups and oxygen atoms (not shown) on one end 321 and the other end 322 are chemically bonded with the amino groups of the organic film 12.

[0049] In this embodiment, the second member 20 has an organic film 22 formed on its contact surface 20a. The organic film 22 is composed of an arbitrary organic material that bonds with the constituent material of the second member 20 and the carbon material 32 of the connecting member 30. The organic film 22 is formed, for example, by coating the contact surface 20a of the second member 20, similar to the organic film 12. If the contact surface 20a of the second member 20 is composed of Al, for example, an arbitrary surface treatment is applied to it, similar to the connecting member 30, so that hydroxyl groups (not shown) are introduced to the contact surface 20a. The second member 20 then chemically bonds with the organic film 22, for example, by dehydration condensation between the hydroxyl groups (not shown) on the contact surface 20a and the silanol groups of the organic film 22. The bonding between the organic films 12 and 22 and the first member 10, the second member 20, and the carbon material 32 can also be referred to as molecular bonding.

[0050] This embodiment also provides a connection structure that offers the same effects as the first embodiment described above. Furthermore, the connection structure of this embodiment also provides the following effects.

[0051] (1) An organic film 12 is provided on the contact surface 10a of the first member 10, and an organic film 22 is provided on the contact surface 20a of the second member 20. The organic films 12 and 22 bond the member 10 or 20 to the carbon material 32, thereby chemically bonding these interfaces. As a result, the connection between the first member 10, the carbon material 32, and the second member 20 is firmly established, and the contact at these interfaces becomes more stable. Furthermore, because the organic films 12 and 22 are single molecular layers, the increase in thermal resistance at the interface between the carbon material 32 and the first member 10 or the second member 20 can be suppressed.

[0052] (Fourth Embodiment) A fourth embodiment will be described with reference to the drawings.

[0053] The connection structure of this embodiment differs from the first embodiment in that, as shown in Figure 16, for example, it includes a third member 40 surrounding the outer circumference of the first member 10 and a sealing material 50 connecting the second member 20 and the third member 40. This embodiment will mainly explain this difference.

[0054] The third member 40 is shaped to surround, for example, part or all of the side surface of the first member 10, and is positioned opposite the second member 20 together with the first member 10. The third member 40 covers, for example, the back surface 10b of the first member 10, opposite to the contact surface 10a. The third member 40 has, for example, a planar size that is larger than that of the first member 10, but smaller than that of the second member 20. The third member 40 is bonded to the second member 20 by, for example, a sealing material 50 that surrounds the entire circumference of the side surface. The third member 40 may be made of, for example, a resin material, a metal material or a composite material thereof, or any other material.

[0055] The sealing material 50 adheres and holds the second member 20 and the third member 40. The sealing material 50 is made of any resin material with adhesive properties, such as epoxy or acrylic. The sealing material 50 is arranged, for example, in a top view, i.e., viewed from the direction normal to the contact surface 20a, so as to surround the side surface of the third member 40 in a continuous frame shape. The sealing material 50 is placed, for example, by coating while the connecting member 30 is pressurized by the first member 10, the third member 40, and the second member 20, but it may also be placed before pressurization. In other words, the sealing material 50 adheres and holds the second member 20 and the third member 40, thereby maintaining the state in which the connecting member 30 is pressurized by the first member 10 and the second member 20, and plays a role in ensuring their thermal connection. The sealing material 50 also seals the gap area between the first member 10 and the third member 40 and the second member 20. As a result, the sealing material 50 plays a role in containing the generated dust in a sealed space, even if dust is generated due to the carbon material 32.

[0056] Furthermore, the sealing material 50 may flow into the gap between the first member 10 and the second member 20, as shown in Figure 17, for example, and a portion of it may enter the void layer 33. When the connecting member 30 is placed under pressure from the first member 10 and the second member 20, the sealing material 50 will not enter between the carbon material 32 and the first member 10 or the second member 20, and will not hinder heat conduction between members 10 and 20. In addition, since the contact area between the connecting member 30 and members 10 and 20 is sufficiently larger than the bonding area due to the sealing material 50, the deformation and stress relaxation effects due to differences in the coefficients of linear expansion of members 10 and 20 are not impaired.

[0057] This embodiment also provides a connection structure that offers the same effects as the first embodiment described above. Furthermore, the connection structure of this embodiment also provides the following effects.

[0058] (1) In this connection structure, the third member 40 surrounding the outer circumference of the first member 10 and the second member 20 are bonded together by a sealing material 50, thereby maintaining the pressurized state of the connecting member 30 by the first member 10 and the second member 20. As a result, the contact between members 10 and 20 and the carbon material 32 is maintained in a stable state, and the effect of ensuring a more continuous connection with high thermal conductivity between members 10 and 20 is obtained. In addition, since the space in which the connecting member 30 is placed is sealed by the sealing material 50, even if dust is generated due to the carbon material 32, it is possible to prevent the generated dust from spreading to the outside.

[0059] (Modification of the fourth embodiment) The connection structure of the fourth embodiment may be a laminate in which the first member 10 is a heat sink 110, an insulating substrate 120, and a metal layer 130 stacked in that order, as shown in Figure 18, for example. In this case, for example, the first member 10 may be a DBC substrate in which the heat sink 110 and the metal layer 130 are made of Cu, and the insulating substrate 120 is a ceramic substrate. DBC is an abbreviation for Direct Bonded Copper.

[0060] Furthermore, in the fourth embodiment, the connection structure may have high-adhesion portions 23 and 41 formed in the parts of the second member 20 and the third member 40 that come into contact with the sealing material 50, such as recesses or grooves into which the sealing material 50 can enter, as shown in Figure 19, for example. The high-adhesion portion 23 is formed on the second member 20 by any method such as laser irradiation or machining, and is a part in which a portion of the sealing material 50 enters and creates an anchoring effect, thereby increasing the adhesion with the sealing material 50 compared to other parts. The high-adhesion portion 41 is formed on the third member 40 by any method and serves the same role as the high-adhesion portion 23. The high-adhesion portions 23 and 41 only need to improve the adhesion with the sealing material 50, and their patterns may be changed as appropriate. Although Figure 19 shows an example in which the first member 10 is a composite member, in this modified example, the first member 10 may be a single member. Also, in this connection structure, only one of the second member 20 and the third member 40 may have high-adhesion portions 23 and 41.

[0061] Furthermore, in the fourth embodiment, as shown in Figure 20, for example, the connection structure may have a fourth member 60 positioned between the first member 10 and the second member 20, with connecting members 30 positioned between the first member 10 and the fourth member 60, and between the second member 20 and the fourth member 60. In this case, the fourth member 60 is made of any material with high thermal conductivity, such as ceramic.

[0062] Furthermore, the connection structure of the fourth embodiment may further include a fifth member 70 that covers the entire adhesive area between the second member 20 and the third member 40, as shown in Figure 21, for example, and the third member 40 may be sealed by the fifth member 70. The fifth member 70 is made of, for example, any resin material. In this modified connection structure, the connection portion between the first member 10 and the second member 20 via the connecting member 30 is double-sealed by the third member 40 and the fifth member 70, thus providing the effect of more stable contact between members 10 and 20 and the carbon material 32.

[0063] The same effects as those of the fourth embodiment described above can be obtained by the modified form described above.

[0064] (Fifth embodiment) A fifth embodiment will be described with reference to the drawings.

[0065] The connection structure of this embodiment differs from the fourth embodiment in that a communication portion 42 is formed on the third member 40, as shown in Figure 22, for example. This embodiment will mainly explain this difference.

[0066] For the sake of explanation, the space enclosed by the first member 10, the third member 40, the second member 20, and the sealing material 50 will be referred to as the "internal space 200". The internal space 200 can also be described as the space in which the connecting member 30 is housed.

[0067] In this embodiment, the third member 40 has a communication portion 42 that connects the internal space 200 and the external space. The communication portion 42 is, for example, a through hole formed along the thickness direction of the third member 40, and is formed by drilling or the like. The communication portion 42 functions as a passage when a fluid such as air in the internal space 200 expands due to heat from an external heat source, and suppresses the increase in internal pressure of the internal space 200. The communication portion 42 only needs to be such that the fluid in the internal space 200 can pass through it, and its number, dimensions, shape, arrangement, etc., may be changed as appropriate.

[0068] This embodiment also provides the same effects as the fourth embodiment described above. Furthermore, the connection structure of this embodiment also provides the following effects.

[0069] (1) Because the third member 40 has a communication portion 42, even if the fluid in the internal space 200 expands due to heat, it can be released to the outside through the communication portion 42, thereby suppressing an increase in internal pressure.

[0070] (Modified version of the fifth embodiment) In the fifth embodiment, the connection structure may be configured such that, as shown in Figure 23, for example, a communication portion 24 is formed on the second member 20 side instead of the third member 40, connecting the internal space 200 and the external space. The communication portion 24 can be formed by any method, similar to the communication portion 42, as long as it connects the internal space 200 and the external space and allows fluid to pass through, and its number, shape, dimensions, arrangement, etc., can be changed as appropriate.

[0071] Furthermore, the connection structure of the fifth embodiment may be configured such that, as shown in Figure 24, for example, the sealing material 50 is divided into multiple parts and arranged so that gaps are created between the sealing materials 50, and these gaps function as communication portions 51. In this case, the second member 20 and the third member 40 do not need to have a configuration that includes communication portions.

[0072] Note that in Figure 24, hatching is applied to the sealing material 50 to make the arrangement example easier to understand, although a cross-section is not shown. Also, Figure 24 shows the top layout of the second member 20 (not shown) as viewed from the normal direction to the contact surface 20a. The same applies to Figures 25 and 26.

[0073] The sealing material 50 may be divided and arranged in two substantially U-shaped patterns, as shown in Figure 24, for example, with the smaller substantially U-shaped pattern inverting in the opposite direction inside the larger substantially U-shaped pattern. In this case, the gap between the two substantially U-shaped patterns functions as a communication portion 51. Alternatively, the sealing material 50 may be divided and arranged in two substantially U-shaped patterns of approximately the same size, as shown in Figure 25, for example, with these two patterns arranged alternately in opposite directions. Furthermore, the sealing material 50 may have an arrangement, as shown in Figure 26, for example, that includes four substantially L-shaped patterns spaced apart from each other to form the corners, and four linear patterns positioned inside the four substantially L-shaped patterns. In this case, each linear pattern is longer than the gap between adjacent substantially L-shaped patterns and is positioned adjacent to the entire area of ​​the gap. In this case, the gap between the linear pattern and the substantially L-shaped pattern functions as a communication portion 51. The pattern shape for dividing and arranging the sealing material 50 is not limited to the example described above and may be changed as appropriate.

[0074] The same effects as those of the fifth embodiment described above can be obtained by the modified form described above.

[0075] (Sixth Embodiment) A sixth embodiment will be described with reference to the drawings.

[0076] The connection structure of this embodiment differs from the first embodiment in that, as shown in Figure 27, for example, the third member 40 is positioned in contact with the side opposite to the side where the first member 10 is exposed, and it further includes a fastening member 80 that presses the first member 10 toward the second member 20 together with the third member 40. This embodiment will mainly explain this difference.

[0077] The fastening member 80 fastens and fixes the third member 40 to the second member 20, and is a member for maintaining the pressurized state of the connecting member 30 formed by the first member 10 and the second member 20. The fastening member 80 is configured such that, for example, it has a base portion 81 which has a larger planar size than the third member 40 and abuts against the side opposite to the side where the first member 10 is exposed, and a screw 82 which is inserted into a screw hole formed in the base portion 81. By inserting the screw 82 into the screw hole 25 of the second member 20, the fastening member 80 is fixed to the second member 20 with the base portion 81 pressing against the first member 10 together with the third member 40. This maintains the pressurized state of the connecting member 30, and allows for good contact between members 10, 20 and the carbon material 32. In other words, the fastening member 80 functions as a pressurizing member for the connecting member 30 sandwiched between members 10, 20. Furthermore, the base portion 81 has screw holes formed in the portion that protrudes from the third member 40, for example.

[0078] This embodiment also provides a connection structure that offers the same effects as the first embodiment described above. Furthermore, the connection structure of this embodiment also provides the following effects.

[0079] (1) The fastening member 80 fixes the first member 10 to the second member 20 and maintains the state in which the connecting member 30 is pressed, so this connection structure has the effect of making the contact state between the first member 10 and the second member 20 and the carbon material 32 more stable.

[0080] (Modified version of the sixth embodiment) In the sixth embodiment, the connection structure may be configured such that, for example as shown in Figure 28, the fastening member 80 consists only of a screw 82, the screw 82 penetrates the third member 40, and the second member 20 and the third member 40 are fastened together with a screw.

[0081] The connection structure of the sixth embodiment may have a configuration in which, instead of the fastening member 80, a pressurizing member 90 pressurizes the first member 10 along with the third member 40, as shown in Figure 29, for example. The pressurizing member 90 has, for example, a plate-shaped member 91 that abuts against the third member 40, an opposing member 92 positioned opposite the plate-shaped member 91, and an elastic body 93 positioned between the plate-shaped member 91 and the opposing member 92. The pressurizing member 90 is configured such that, for example, the elastic body 93 is compressed and positioned between the plate-shaped member 91 and the opposing member 92, and the restoring force presses against the plate-shaped member 91. The opposing member 92 is, for example, any member fixed to something, and is configured not to deform due to the restoring force of the elastic body 93. Even with such a configuration, the connection member 30 maintains a state in which the third member 40 is pressed by the first member 10 and the second member 20. The pressurizing member 90 may be made of a resin material, a metal material, a composite material thereof, or any other material.

[0082] The modified form described above also provides a connection structure that offers the same effects as the sixth embodiment described above.

[0083] (Other embodiments) This disclosure is described in accordance with the embodiments, but it is understood that this disclosure is not limited to such embodiments or structures. This disclosure also includes various modifications and variations within the equivalence range. In addition, various combinations and forms, as well as other combinations and forms including one, more, or less of those elements, fall within the scope and concept of this disclosure.

[0084] (1) In each of the above embodiments, the connection structure may be such that the first member 10 is a semiconductor module, as shown in Figure 30, for example. For example, the semiconductor module has a configuration comprising a semiconductor element 140, a laminate of a heat sink 110, an insulating substrate 120, and a metal layer 130, and a molded resin 150 that covers the semiconductor element 140 and a part of the laminate. The semiconductor module may also have a configuration in which, for example, the semiconductor element 140 is joined to the metal layer 130 by solder (not shown), and the heat sink 110 is exposed from the molded resin 150. The semiconductor element 140 is a heat-generating element such as a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) or an IGBT (Insulated Gate Bipolar Transistor), and is connected to wires, metal clips (not shown). The semiconductor module is thermally connected to the connection member 30 by the heat sink 110. In this case, for example, the second member 20 is a heat sink such as a cooler made of Al. Figure 30 shows an example in which the connection structure of the fourth embodiment is a semiconductor device in which a semiconductor element and a cooler are connected via a connecting member 30, but other embodiments can also be applied to semiconductor devices.

[0085] (2) The connection structure of the fourth embodiment described above can constitute an insulating embedded substrate in which the first member 10 is a conductive layer such as a metal plate or a graphite heat sink, and the second member 20 is a ceramic substrate, as shown in Figure 31, for example. In this case, the insulating embedded substrate has a structure in which the main thermal connection between the first member 10 and the second member 20 is made by the connecting member 30, and the joined area is only the part made of the sealing material 50, so even if the thickness of the first member 10 is increased, the effect of stress is reduced. Furthermore, the insulating embedded substrate to which this connection structure is applied has a smaller joined area and reduced stress compared to the conventional configuration in which the conductive layer and the insulating layer are mostly connected by brazing material, so it has a high degree of design freedom. Furthermore, when the first member 10 is a graphite heat sink, it is preferable that the connecting member 30 is arranged so that the direction of heat conduction in the plane intersects with the direction of heat conduction in the plane of the first member 10, which is a graphite heat sink, as shown in Figure 32, for example. For example, in Figure 32, the left-right direction on the paper is defined as the x-direction, the direction perpendicular to the x-direction is defined as the y-direction, and the direction perpendicular to the xy-plane is defined as the z-direction. For example, if the first member 10 has a configuration in which multiple graphites 13 extend along the y-direction and are arranged parallel to each other in the x-direction, then its heat conduction direction is the yz-direction. In this case, the heat conduction direction of the first member 10 in the xy-plane is the y-direction. In such a case, it is preferable that the connecting member 30 is arranged such that, for example, the carbon material 32 extends in the x-direction, that is, the heat conduction direction in the xy-plane is the x-direction. This results in a configuration that further improves the efficiency of heat conduction in the xy-plane.

[0086] It goes without saying that, in each of the above embodiments, the elements constituting the embodiment are not necessarily essential unless explicitly stated to be particularly essential or unless they are clearly considered essential in principle. Furthermore, in each of the above embodiments, when numerical values ​​such as the number, numerical values, quantities, or ranges of the components of the embodiment are mentioned, the embodiment is not limited to those specific numbers unless explicitly stated to be particularly essential or unless it is clearly limited to a specific number in principle. Furthermore, in each of the above embodiments, when the shape, positional relationship, etc., of the components are mentioned, the embodiment is not limited to those shapes, positional relationships, etc., unless explicitly stated or unless it is clearly limited to a specific shape, positional relationship, etc., in principle.

[0087] (Features of the present invention) [Claim 1] First member (10) and A second member (20) is positioned opposite the first member and is made of a material with a different coefficient of thermal expansion than the first member, A connecting structure comprising a heat-resistant resin material (31), a carbon material (32) composed of carbon atoms, and a void layer (33), and a connecting member (30) that connects the first member and the second member. [Claim 2] The connection structure according to claim 1, wherein one end of the carbon material is in contact with the first member, and the other end opposite to the first end is in contact with the second member. [Claim 3] The connection structure according to claim 1 or 2, wherein the carbon material has a heat conduction direction (D2) in which it connects the first member and the second member, and the angle between the thickness direction (D1) of the connecting member and the heat conduction direction of the carbon material is within the range of 14° to 70°. [Claim 4] The connection structure according to any one of claims 1 to 3, wherein the contact surfaces (10a, 20a) of the first member and the second member that come into contact with the carbon material have recesses (11, 21) that increase the frictional force with the carbon material. [Claim 5] The connection structure according to any one of claims 1 to 3, wherein the contact surfaces (10a, 20a) of the first member and the second member that come into contact with the carbon material have organic films (12, 22) formed on them that bond with the carbon material. [Claim 6] The connecting structure according to claim 5, wherein the organic film is composed of an organic material having a triazine ring. [Claim 7] A third member (40) surrounds the outer periphery of the first member and is positioned opposite the second member, The connection structure according to any one of claims 1 to 6, further comprising a frame-shaped sealing material (50) that surrounds the outer periphery of the connecting member and connects the second member and the third member. [Claim 8] The connection structure according to claim 7, wherein the space enclosed by the second member, the third member and the sealing material is defined as an internal space (200), and at least one of the second member and the third member has a communication portion (24, 42) that connects the internal space and the external space. [Claim 9] A third member (40) surrounds the outer periphery of the first member and is positioned opposite the second member, The connecting member further comprises a sealing material (50) that surrounds the outer periphery of the connecting member and connects the second member and the third member, The connection structure according to any one of claims 1 to 6, wherein the space located between the second member and the third member is defined as an internal space (200), and the sealing material is arranged such that a gap is created which forms a communication portion (51) that connects the internal space and the external space. [Claim 10] The connection structure according to any one of claims 7 to 9, wherein at least one of the second member and the third member is provided with a high-adhesion portion (23, 41) having a recess into which a portion of the sealing material enters and which has a higher adhesion with the sealing material than other parts of the second member and the third member. [Claim 11] The connection structure according to any one of claims 2 to 10, wherein the carbon material is chemically modified in the portion that contacts the first member and the portion that contacts the second member, and is chemically bonded with the first member and the second member. [Claim 12] The connection structure according to any one of claims 2 to 10, further comprising pressurizing members (80, 90) that press the connecting member against the other of the first member and the second member via one of the first member and the second member. [Claim 13] A semiconductor module (10) having a semiconductor element (140) and a heat sink (110) thermally connected to the semiconductor element, A heat sink (20) of the semiconductor module is positioned opposite the heat sink, A semiconductor device comprising a heat-resistant resin material (31), a carbon material (32) composed of carbon atoms, and a void layer (33), and a connecting member (30) that connects the semiconductor module and the heat sink. [Claim 14] A conductive layer (10) made of a conductive material, An insulating substrate (20) made of an insulating material is disposed opposite the conductive layer, An insulating substrate comprising a heat-resistant resin material (31), a carbon material (32) composed of carbon atoms, and a void layer (33), and a connecting member (30) that connects the conductive layer and the insulating substrate. [Explanation of Symbols]

[0088] 10...First component (semiconductor element, conductive layer), 10a, 20a...Contact surface, 11, 21...Recess, 12, 22...Organic film, 20...Second component (heat sink, insulating substrate), 23, 41...High adhesion section, 24, 42, 51...Communication section, 30...Connecting member, 31...High heat-resistant resin material, 32...Carbon material, 33...Void layer, 40...Third component, 50...Sealing material, 80, 90...Pressurizing member, 110...Heat sink, 140...Semiconductor element, 200...Internal space, D1...Thickness direction, D2...Heat conduction direction

Claims

1. First member (10) and A second member (20) is positioned opposite the first member and is made of a material with a different coefficient of thermal expansion than the first member, A connecting member (30) that connects the first member and the second member, comprising a high heat-resistant resin material (31), a carbon material (32) composed of carbon atoms, and a void layer (33), The device comprises pressurizing members (80, 90) that press the connecting member against the other of the first and second members via one of the first and second members, The carbon material has a connecting structure in which one end is in contact with the first member and the other end opposite to the first end is in contact with the second member.

2. First member (10) and A second member (20) is positioned opposite the first member and is made of a material with a different coefficient of thermal expansion than the first member, A connecting member (30) that connects the first member and the second member, comprising a high heat-resistant resin material (31), a carbon material (32) composed of carbon atoms, and a void layer (33), A third member (40) surrounds the outer periphery of the first member and is positioned opposite the second member, The connecting member is surrounded by a frame-shaped sealing material (50) that connects the second member and the third member, The connection structure according to claim 1, wherein one end of the carbon material is in contact with the first member, and the other end opposite to the first end is in contact with the second member.

3. The connection structure according to claim 2, wherein the space enclosed by the second member, the third member and the sealing material is defined as an internal space (200), and at least one of the second member and the third member has a communication portion (24, 42) that connects the internal space and the external space.

4. The connection structure according to claim 2, wherein the space located between the second member and the third member is defined as the internal space (200), and the sealing material is arranged such that a gap is created that forms a communication portion (51) that connects the internal space and the external space.

5. The connection structure according to claim 2, wherein at least one of the second member and the third member is provided with a high-adhesion portion (23, 41) having a recess into which a portion of the sealing material enters and which has a higher adhesion with the sealing material than other parts of the second member and the third member.

6. The connection structure according to any one of claims 1 to 5, wherein the carbon material has a heat conduction direction (D2) in which it connects the first member and the second member, and the angle between the thickness direction (D1) of the connecting member and the heat conduction direction of the carbon material is within the range of 14° to 70°.

7. The connection structure according to any one of claims 1 to 5, wherein the contact surfaces (10a, 20a) of the first member and the second member that come into contact with the carbon material have recesses (11, 21) that increase the frictional force with the carbon material.

8. The connection structure according to any one of claims 1 to 5, wherein the contact surfaces (10a, 20a) of the first member and the second member that come into contact with the carbon material have organic films (12, 22) formed on them that bond with the carbon material.

9. The connection structure according to any one of claims 1 to 5, wherein the carbon material is chemically modified in the portion that contacts the first member and the portion that contacts the second member, and is chemically bonded with the first member and the second member.

10. A semiconductor module (10) having a semiconductor element (140) and a heat sink (110) thermally connected to the semiconductor element, A heat sink (20) of the semiconductor module is positioned opposite the heat sink plate, A connecting member (30) for connecting the semiconductor module and the heat sink, comprising a high heat-resistant resin material (31), a carbon material (32) composed of carbon atoms, and a void layer (33), The device comprises pressurizing members (80, 90) that press the connecting member against the other of the heat sink and the heat sink via one of the heat sink and the heat sink, The semiconductor device comprises a carbon material in which one end is in contact with the heat sink and the other end opposite to the first end is in contact with the heat sink.

11. A conductive layer (10) made of a conductive material, An insulating substrate (20) made of an insulating material is disposed opposite the conductive layer, A connecting member (30) comprising a high heat-resistant resin material (31), a carbon material (32) composed of carbon atoms, and a void layer (33), connects the conductive layer and the insulating substrate. A third member (40) surrounds the outer periphery of the conductive layer and is positioned opposite the insulating substrate, The connecting member is surrounded by a frame-shaped sealing material (50) that connects the insulating substrate and the third member, The carbon material is an insulating substrate having one end in contact with the conductive layer and the other end opposite to the first end in contact with the insulating substrate.

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