Heat dissipation component, method for manufacturing a heat dissipation component, housing and substrate

Abstract

A heat dissipation component (11) comprises: a sintered material section containing copper and at least one of tungsten and molybdenum; and a plurality of silicon oxide particles dispersed in the sintered material section. The heat dissipation component (11) has a copper content of M Cu weight percent, a tungsten content of M W weight percent, a molybdenum content of M Mo weight percent and a silicon oxide content of M SiO2 Weight percent, based on SiO2 equivalent, relative to the total weight of copper, tungsten, and molybdenum. The heat dissipation component fulfills: 0.9 ≥ M Cu / (M Cu + Mw + M Mo ) ≥ 0.045 and 0.01 ≥ M SiO2 / (M Cu + Mw + M Mo ) ≥ 0.0003.

Description

TECHNICAL AREA

[0001] The present disclosure relates to a heat dissipation component, a method for manufacturing a heat dissipation component or a heat dissipation component manufacturing process, a housing and a substrate. TECHNICAL BACKGROUND

[0002] A heat dissipation component is sometimes used to promote heat dissipation from a semiconductor device operating at a relatively high current, such as a power semiconductor device. The heat dissipation component is sometimes used while connected to a component (hereinafter also referred to as a component made of a different material) that is constructed from a different material than the heat dissipation component.

[0003] For example, a housing disclosed in Japanese patent application Disclosure No. 2015-204426 (Patent Document 1) includes a heat sink plate (the heat dissipation component) and a ceramic frame (the component made of another material). The heat sink plate serves to dissipate the heat generated by an electronic component mounted on its upper surface. The ceramic frame is connected to the heat sink plate to surround one side in which the electronic component is mounted. They are joined by brazing. The brazing temperature is approximately 780°C. The ceramic frame is made, for example, of aluminum oxide or aluminum nitride.

[0004] The aforementioned heatsink plate is a metal plate. A metal plate with high thermal conductivity is selected to mitigate the deformation of the housing caused by a difference in its coefficient of linear expansion compared to the ceramic frame during brazing. For example, a composite metal plate or a clad metal plate is used. The composite metal plate is produced, for instance, by impregnation. Specifically, it is formed by impregnating a porous plate of a high-melting-point metal with copper (Cu). High-melting-point metals, such as tungsten (W) and molybdenum (Mo), have a similar coefficient of linear expansion to ceramic, allowing the heatsink plate to have a similar coefficient of linear expansion to the ceramic frame. Cu has excellent thermal conductivity, enabling the heatsink plate to achieve high heat dissipation performance.

[0005] If the heatsink plate needs to have a similar coefficient of linear expansion to the ceramic frame, a composite metal plate or a clad metal plate is often used, as described above. If matching the coefficients of linear expansion is not important, a simple metal material is often used, and the thermal conductivity can be significantly increased, for example, by using pure copper. DOCUMENTS ON THE STATE OF THE TECHNOLOGY PATENT DOCUMENT

[0006] Patent specification 1: Japanese patent application disclosure no. 2015-204426 Brief description of the problem to be solved by the invention

[0007] When the enclosure is subjected to a thermal cycle, the differential thermal expansion between the heat dissipation component and the component made of a different material exerts a thermal stress on the interface between these components. As a result, the interface or the component made of the other material can be damaged (typically by cracking). According to the technology disclosed in the aforementioned Japanese patent application, publication no. 2015-204426, the difference in thermal expansion between the heat sink plate (heat dissipation component) and the ceramic frame (component made of a different material) can be relatively small, but not completely eliminated.Furthermore, W and Mo exhibit high stiffness, so if the W or Mo content of the heat dissipation component is increased to suppress the difference in thermal expansion, the heat dissipation component will have a high modulus of elasticity. This will tend to reduce the effectiveness of mitigating thermal stress through elastic deformation of the heat dissipation component. In this case, the difference in thermal expansion is more likely to directly damage the joint or the component made of a different material. While many materials with low moduli of elasticity exist, no suitable material has yet been found that combines moderate thermal expansion with good thermal conductivity.

[0008] The present disclosure was designed to solve a problem as described above, and it is an object of the present disclosure to provide a heat dissipation component that is able to suppress a reduction in the reliability of a joint or component to be joined made of a different material, which is caused by a difference in thermal expansion compared to the component made of a different material, while having a similar coefficient of thermal expansion to a ceramic material and good thermal conductivity. MEANS TO SOLVENT THE PROBLEM

[0009] Aspect 1 is a heat dissipation component comprising: a sintered material section containing copper and at least one of tungsten and molybdenum; and a plurality of silicon oxide particles dispersed in the sintered material section, wherein the heat dissipation component has a copper content of M Cuweight percent, a tungsten content of M W weight percent, a molybdenum content of M Mo weight percent and a silicon oxide content of M SiO2 Weight percent, based on SiO2 equivalent, relative to the total weight of copper, tungsten and molybdenum, where the heat dissipation component fulfills: 0.9 ≥ M Cu / (M Cu + M W + M Mo ) ≥ 0.045 and 0.01 ≥ M SiO2 / (M Cu + M W + M Mo ) ≥ 0.0003.

[0010] Aspect 2 is the heat dissipation component according to aspect 1, wherein in the particle size distribution, based on the number of particles in a particle size range of the multitude of silicon oxide particles of 0.2 µm or more and less than 10 µm, the percentage share of a particle size range of 0.2 µm or more and less than 1.0 µm is 70% or more.

[0011] Aspect 3 is the heat dissipation component according to aspect 2, wherein the multitude of silicon oxide particles each have a particle size of less than 10 µm.

[0012] Aspect 4 is the heat dissipation component according to aspect 1, wherein in the particle size distribution, based on the number of particles in a particle size range of the multitude of silicon oxide particles of 0.2 µm or more and less than 5 µm, the percentage share of a particle size range of 0.2 µm or more and less than 1.0 µm is 70% or more.

[0013] Aspect 5 is the heat dissipation component according to aspect 4, wherein the multitude of silicon oxide particles each have a particle size of less than 5 µm.

[0014] Aspect 6 is the heat dissipation component according to aspect 1, wherein in the particle size distribution, based on the number of particles in a particle size range of the multitude of silicon oxide particles of 0.2 µm or more and less than 3 µm, the percentage share of a particle size range of 0.2 µm or more and less than 1.0 µm is 70% or more.

[0015] Aspect 7 is the heat dissipation component according to aspect 6, wherein the multitude of silicon oxide particles each have a particle size of less than 3 µm.

[0016] Aspect 8 is the heat dissipation component according to aspect 1, wherein in the particle size distribution, based on the number of particles in a particle size range of the multitude of silicon oxide particles of 0.2 µm or more and less than 2 µm, the percentage share of a particle size range of 0.2 µm or more and less than 1.0 µm is 70% or more.

[0017] Aspect 9 is the heat dissipation component according to aspect 8, wherein the multitude of silicon oxide particles each have a particle size of less than 2 µm.

[0018] Aspect 10 is the heat dissipation component according to one of aspects 1 to 9, where the heat dissipation component is 0.80 ≥ M Cu / (M Cu + M W + M Mo ) ≥ 0.15 is fulfilled.

[0019] Aspect 11 is the heat dissipation component according to one of aspects 1 to 10, wherein the remainder of the heat dissipation component, other than copper, tungsten, molybdenum and silicon oxide, constitutes less than 0.5 percent by weight, relative to the total weight.

[0020] Aspect 12 is the heat dissipation component according to one of aspects 1 to 11, where the heat dissipation component fulfills: M Mo = 0 and 0.806 ≥ M Cu / (M Cu + M W ) ≥ 0.075.

[0021] Aspect 13 is the heat dissipation component according to one of aspects 1 to 11, where the heat dissipation component fulfills: M W = 0 and 0.887 ≥ M Cu / (M Cu + M Mo ) ≥ 0.133.

[0022] Aspect 14 is a heat dissipation component manufacturing process according to one of Aspects 1 to 13, wherein the heat dissipation component manufacturing process comprises: mixing at least one of: tungsten powder with an average particle size of 0.5 µm or more and 10 µm or less, molybdenum powder with an average particle size of 0.5 µm or more and 10 µm or less, copper powder with an average particle size of 1.5 µm or more and 5.0 µm or less, and SiO2 powder with an average particle size of 7 nm or more and 200 nm or less to form a mixed powder, wherein the mixed powder has a copper content of M Cu(P) weight percent, a tungsten content of M W(P)weight percent, a molybdenum content of M Mo(P) weight percent and a silicon oxide content of M SiO2(P) weight percent in terms of SiO2 equivalent, relative to the total weight of copper, tungsten and molybdenum, wherein the mixed powder has 0.9 ≥ M Cu(P) / (M Cu(P) + M W(P) + M Mo(P) ) ≥ 0.045 and 0.03 ≥ M SiO2(P) / (M Cu(P) + M W(P) + M Mo(P) ) ≥ 0.001 is met; and heating the mixed powder to a temperature at or above the melting point of copper.

[0023] Aspect 15 is the heat dissipation component manufacturing process according to aspect 14, which further includes the forming of at least one green plate containing the mixing powder and a resin, wherein the firing of the mixing powder is carried out by firing the at least one green plate.

[0024] Aspect 16 is the heat dissipation component manufacturing process according to aspect 15, wherein the at least one green plate comprises a plurality of green plates, wherein the manufacturing process further comprises laminating the plurality of green plates to form a laminate body, and wherein the firing of the mixed powder is carried out by firing the laminate body.

[0025] Aspect 17 is a housing comprising: the heat dissipation component according to any one of Aspects 1 to 13; and a ceramic frame, wherein the heat dissipation component has a heat dissipation surface and a main surface opposite the heat dissipation surface, and the ceramic frame is arranged on the main surface of the heat dissipation component and has an inner surface surrounding a cavity and an outer surface opposite the inner surface.

[0026] Aspect 18 is a substrate comprising: the heat dissipation component according to one of Aspects 1 to 13; and a ceramic insulating layer, wherein the heat dissipation component has a heat dissipation surface and a main surface opposite the heat dissipation surface and the ceramic insulating layer is arranged on the main surface of the heat dissipation component. EFFECTS OF THE INVENTION

[0027] According to aspect 1 described above, the heat dissipation component, due to its copper content, tends to exhibit good thermal conductivity, and its content of at least one of each of tungsten and molybdenum allows for adjustment of the coefficient of thermal expansion. Furthermore, the elastic modulus can be suppressed by the silicon oxide content, while a significant negative impact on thermal conductivity can be avoided by keeping the silicon oxide content relatively low. Consequently, a reduction in the reliability of a joint or component made of another material that is to be connected to the heat dissipation component, caused by a difference in thermal expansion compared to the component made of the other material, can be mitigated, while the heat dissipation component itself exhibits moderate thermal expansion and good thermal conductivity.

[0028] These and other tasks, features, aspects and advantages of the present disclosure will become clearer from the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS [ Fig. Figure 1] is a schematic perspective view showing a configuration of a semiconductor module according to embodiment 1, with a section of it omitted so that the interior of a cavity is visible. [ Fig. Figure 2] is a schematic cross-sectional view of the semiconductor module along line II-II in Fig. 1. [ Fig. Figure 3] is a schematic cross-sectional view showing a configuration of a housing as a component of the semiconductor module. Fig. 2 shows. [ Fig. Figure 4] is a flowchart that schematically shows a method for manufacturing the housing according to embodiment 1. [ Fig.Figure 5] is a schematic partial cross-sectional view showing one step of the process for manufacturing the housing according to embodiment 1. [ Fig. [6] is an enlarged view of a section of Fig. 5. [ Fig. Figure 7] is a schematic partial cross-sectional view showing one step of the process for manufacturing the housing according to embodiment 1. [ Fig. Figure 8] is a schematic partial cross-sectional view showing one step of the process for manufacturing the housing according to embodiment 1. [ Fig. Figure 9] is a schematic cross-sectional view showing a configuration of a semiconductor module according to embodiment 2. [ Fig.

[10] is an electron microscope image of a cross-section of a heat dissipation component in Example 2. [ Fig.

[11] is an electron microscope image of a cross-section of a heat dissipation component in Example 3. [ Fig.

[12] is an electron microscope image of a cross-section of a heat dissipation component in Example 9. [ Fig. 13] contains a diagram (a) showing the relationship between the copper content and the stress at 1% strain of a heat dissipation component containing copper and tungsten, and a diagram (b) showing the relationship between the copper content and the stress at 1% strain of a heat dissipation component containing copper and molybdenum. [ Fig. 14] contains a diagram (a) showing the relationship between the coefficient of thermal expansion and the stress at 1% strain of the heat dissipation component containing copper and tungsten, and a diagram (b) showing the relationship between the coefficient of thermal expansion and the stress at 1% strain of the heat dissipation component containing copper and molybdenum. [ Fig.

[15] is a diagram that schematically shows a fine structure of a heat dissipation component in which no silicon oxide particles are dispersed. [ Fig.

[16] is a diagram that schematically shows a fine structure of a heat dissipation component in which silicon oxide particles are dispersed. [ Fig. Figure 17] is a schematic cross-sectional view showing a configuration of a semiconductor module according to embodiment 4. [ Fig.

[18] is a schematic cross-sectional view showing a configuration of a heat dissipation substrate as a component of the semiconductor module. Fig. 17 shows. [ Fig. Figure 19] is a schematic partial cross-sectional view showing one step of a method for producing the heat dissipation substrate according to embodiment 4. DESCRIPTION OF THE EXECUTION FORMS

[0029] Embodiments of the present invention are described below with reference to the drawings. <Ausführungsform 1> (Configuration of a semiconductor module)

[0030] Fig. Figure 1 is a schematic perspective view showing a configuration of a semiconductor module 91 according to embodiment 1. Fig. Figure 2 is a schematic cross-sectional view of the semiconductor module 91 along line II-II in Fig. 1. The semiconductor module 91 comprises a housing 51 and a semiconductor element 8. The semiconductor module 91 may include wires 9 as wiring components for the semiconductor element 8. The semiconductor module 91 may include a cover 80 for closing a cavity CV. The cover 80 may be attached to the housing 51 by an adhesive layer 70. Sections of the cover 80 and the adhesive layer 70 are shown in Fig. 1 not shown, so that the interior of the cavity CV of the housing 51 is partially visible.

[0031] Semiconductor element 8 is typically a power semiconductor element, and in this case, semiconductor module 91 is a power module. The power semiconductor element may be designed for high frequency (RF) operation, and in this case, semiconductor module 91 is an RF power module. Semiconductor element 8 is not limited to the power semiconductor element and may, for example, be a high-power, highly integrated circuit (LSI) or an integrated circuit (IC). While in the Fig. 1 and Fig. Where 2 a semiconductor element 8 is shown, a plurality of semiconductor elements 8 can be mounted on the housing 51. An element other than the semiconductor element 8, for example a passive element, can also be mounted. (Configuration of the case)

[0032] Fig.Figure 3 is a schematic cross-sectional view showing a configuration of the housing 51 as a component of the semiconductor module 91 ( Fig. 2) shows. At a time when the housing 51 is being prepared for the manufacture of the semiconductor module 91, the semiconductor element 8 may not yet be mounted, as shown in Fig. Figure 3 shows the housing 51, which has the cavity CV that is to be closed with the cover 80. The housing 51 contains a heat dissipation plate 11 (heat dissipation component) and a ceramic frame 21.

[0033] The heat dissipation plate 11 has a heat dissipation surface P1 and a main surface P2 opposite the heat dissipation surface P1. The heat dissipation surface P1 of the heat dissipation plate 11 is typically attached to a supporting component (not shown). The supporting component is, for example, a mounting plate or a heat dissipation component. The heat dissipation plate 11 may have a through-section (not shown) through which a fastening device (e.g., a screw) is passed for attachment to the supporting component.

[0034] The ceramic frame 21 is a frame formed from ceramic. Using the ceramic frame 21 as the frame of the housing 51 can increase the thermal resistance and insulation of the housing 51. The material for the ceramic frame 21 can contain aluminum oxide as the main component and may contain a trace amount of silicon dioxide to promote the sintering of the ceramic frame 21.

[0035] The ceramic frame 21 is arranged on the main surface P2 of the heat dissipation plate 11. The ceramic frame 21 has an inner surface P3 that surrounds the cavity CV and an outer surface P4a that faces the inner surface P3. The heat dissipation plate 11 may have a side surface P4b that is flush with the outer surface P4a of the ceramic frame 21. An outer edge of the ceramic frame 21 may have a rectangular shape, as shown in Fig. 1 is shown in a plane perpendicular to the thickness direction. Each side of the rectangular shape, for example, has a length of 4 mm or more and 40 mm or less. The ceramic frame 21, for example, has a thickness of 0.1 mm or more and 1 mm or less.

[0036] In embodiment 1, the main surface P2 of the heat dissipation plate 11 includes a cavity surface P2a facing the cavity CV and a connecting surface P2b directly connected to the ceramic frame 21. The ceramic frame 21 and the heat dissipation plate 11 are thus directly connected to each other. The term "directly connected" here means that no component other than a component from the heat dissipation plate 11 and the ceramic frame 21 is present at the connection point.

[0037] The housing 51 can contain a conductor frame 30 (metal connection). The conductor frame 30 is arranged on the ceramic frame 21 and separated from the heat dissipation plate 11 by the ceramic frame 21. The conductor frame 30 forms an electrical path connecting the interior and exterior of the cavity CV. A bonding material (not shown) can be arranged between the conductor frame 30 and the ceramic frame 21 to connect them. The bonding material can be formed, for example, by silver sintering, in which case the aforementioned bonding material is a mixture of a thermally curable resin (e.g., an epoxy resin or a silicone resin) and silver particles. A silver solder joint can be used as the bonding material. In this case, a metallization layer for the silver solder joint is typically formed on the ceramic frame 21 beforehand.

[0038] As an example of a process for forming the metallization layer, a paste intended to form the metallization layer is first printed onto a green plate intended to form the ceramic frame 21, before a firing step is carried out to form the ceramic frame 21 and the heat dissipation plate 11 (described in detail below). Specifically, metal powders consisting of at least one of W, Mo, and Cu, an additive, a resin, a solvent, and the like are first mixed, and if necessary, further ceramic powder is added and kneaded to produce the paste. The paste is printed, for example, by screen printing, onto the green plate produced in the previous step. After printing, the green plate is dried, for example, at a temperature of 110°C for five minutes.Alternatively, the metallization layer can be formed by laminating a metal-containing green plate onto the green plate that is to form the ceramic frame 21, prior to the firing step to form the ceramic frame 21 and the heat dissipation plate 11 (described in detail below).

[0039] The lid 80 ( Fig. 1 and Fig. 2) It can be made of ceramic, which may contain aluminum oxide as its main component and is essentially composed of aluminum oxide. Alternatively, the lid 80 can contain a resin. The resin is, for example, a liquid crystal polymer. Inorganic fillers may be dispersed in the resin, and these inorganic fillers are, for example, silicon dioxide particles. The dispersion of the inorganic fillers in the resin can increase the strength and durability of the lid 80.

[0040] The semiconductor element 8 ( Fig. 2) should be applied to the cavity surface P2a ( Fig.3) attached to the main surface P2 of the heat dissipation plate 11 of the housing 51. The distance L1 ( Fig. 2) The distance between the attached semiconductor element 8 and the inner surface P3 of the ceramic frame 21 can be 25 µm or less. The distance L1 can be zero. In other words, the semiconductor element 8 and the inner surface P3 of the ceramic frame 21 can be in contact with each other. As described above, the distance L1 can be compared to a distance L9 ( Fig. 9: In embodiment 2) slightly reduce. This is because the semiconductor element 8 and a brazing material layer 26 do not impede each other. The brazing material layer 26 is fluid during forming and flows, as shown in Fig.9, shown, into the interior of an inner circumferential surface (a surface facing the cavity CV) of a ceramic frame 29. A section of the brazing material layer 26, which has flowed into the cavity CV, forms a fillet 26f at an edge of the cavity CV. The flow distance, i.e., the width of the fillet 26f, is likely greater than 25 µm. In order to sufficiently reduce the possibility of interference between the fillet 26f and the semiconductor element 8, the distance L9 ( Fig.9) The distance between the semiconductor element 8 and the inner surface of the ceramic frame 29 must be greater than 25 µm. Due to this need for a large distance between the semiconductor element 8 and the ceramic frame 29, the footprint (the area of ​​a region in which the semiconductor element 8 can be mounted) in the cavity CV is reduced. Furthermore, the wires 9 become longer, which generally leads to a deterioration of the electrical properties, such as an unintended increase in inductance.

[0041] The semiconductor element 8 can be attached, for example, using a soldering material (not shown). After attaching the semiconductor element 8, the wires 9 ( Fig.2) are formed to electrically connect the semiconductor element 8 to the conductor frame 30. They can be formed by wire bonding. The cover 80 can then be attached to the housing 51. It can be attached using the adhesive layer 70. The adhesive layer 70 can be a thermosetting resin. The adhesive layer 70 is arranged on the ceramic frame 21 to surround the cavity CV. The adhesive layer 70 can include a section that is arranged over the conductor frame 30 on the ceramic frame 21, as shown in Fig. Figure 2 shows the adhesive layer 70 having a thickness between the cover 80 and the housing 51 of, for example, 100 µm or more and 360 µm or less.

[0042] In embodiment 1, the ceramic frame 21 and the heat dissipation plate 11 are formed as a single, fired body SF. The ceramic frame 21 and the heat dissipation plate 11 are thus directly connected to each other. Therefore, there is no bonding layer (e.g., the brazing material layer 26) between the ceramic frame 21 and the heat dissipation plate 11. Fig. 9: Embodiment 2)) arranged for joining the same. As a brazing material layer 26 ( Fig. 9: In embodiment 2), an Ag brazing material is typically used. If the brazing material layer contains 26 Ag, Ag migration is likely to occur, as indicated by arrow MG ( Fig.9) is indicated when a negative potential is applied to the conductor frame 30 relative to the potential of the heat dissipation plate 11 for an extended period of time. Ag migration can lead to insufficient electrical insulation between the heat dissipation plate 11 and the conductor frame 30. According to embodiment 1, this phenomenon can be prevented. (Material for the heat dissipation plate)

[0043] The heat dissipation plate 11 is a sintered body containing a sintered material section containing copper and a high-melting-point metal, as well as a plurality of silicon oxide particles dispersed in the sintered material section. The high-melting-point metal has a higher melting point than copper. The high-melting-point metal used in the present embodiment is tungsten and / or molybdenum, i.e., at least one of tungsten and one of molybdenum. The plurality of silicon oxide particles can be sintered together with the sintered material section. The sintered material section can constitute a large part of the heat dissipation plate 11.

[0044] To increase the heat dissipation performance of the heat dissipation plate 11, the material for the heat dissipation plate 11 preferably has a high thermal conductivity. Such high thermal conductivity is easily achieved if the heat dissipation plate 11 contains a sufficient proportion of copper. On the other hand, copper has a higher coefficient of linear expansion than a typical ceramic material (e.g., aluminum oxide), so an excessive copper content in the heat dissipation plate 11 is likely to lead to a problem of differential thermal expansion between the heat dissipation plate 11 and the ceramic frame 29.

[0045] If the heat dissipation plate 11 contains a sufficient proportion of at least one of the elements W and Mo, it can exhibit a linear coefficient of thermal expansion closer to that of ceramics such as aluminum oxide, compared to a case where the heat dissipation plate contains almost exclusively Cu. The difference in thermal expansion between the heat dissipation plate 11 and the ceramic frame 21 can thus be reduced. Conversely, if the W or Mo content of the heat dissipation plate 11 is increased, the heat dissipation plate 11 exhibits a high modulus of elasticity due to the high stiffness of W and Mo. This reduces the effect of mitigating thermal stress through elastic deformation of the heat dissipation plate 11.The difference in thermal expansion therefore likely leads to thermal stress at the connection point between the heat dissipation plate 11 and the ceramic frame 21, or at the ceramic frame 21 itself. This difference in thermal expansion can therefore directly damage the connection point between the heat dissipation plate 11 and the ceramic frame 21, or the ceramic frame 21 itself. Suppressing the elastic modulus of the heat dissipation plate 11 is therefore desirable. For this purpose, the heat dissipation plate 11 contains silicon dioxide, as described in detail below.

[0046] The heat dissipation plate 11 contains Cu, at least one of W and Mo, and silicon dioxide. The heat dissipation plate 11 has a Cu content of M Cu wt.% (weight percent), a W content of M W wt.% and a molybdenum content of M Mo wt.% relative to the total weight of Cu, W and Mo. Thus, the equation M applies. Cuwt.% + M W wt.% + M Mo wt.% = 100 wt.%. Relative to the total weight, the silicon dioxide content M is... SiO2 wt% in relation to SiO2 equivalent. A specific method for measuring the silicon oxide content of the heat dissipation plate 11 is described below.

[0047] The composition of the heat dissipation plate 11 meets the following conditions: 0.9≥MCu / (MCu+MW+MMo)≥0.045 and 0.01≥MSiO2 / (MCu+MW+MMo)≥0.0003.

[0048] If M Cu / (M Cu + M W + M Mo If the coefficient of thermal conductivity (Cμ) is less than 0.045, the heat dissipation plate has poor thermal conductivity. Cu / (M Cu + M W + M MoIf the coefficient of thermal expansion is greater than 0.9, it is less likely that the coefficient of thermal expansion will match that of another component, such as a ceramic-molded frame and a mounting plate, and as a result, deformation or cracking may occur. SiO2 / (M Cu + M W + M Mo If M is less than 0.0003, no significant effect on suppressing the elastic modulus of the heat dissipation plate 11 can be achieved. SiO2 / (M Cu + M W + M Mo If the coefficient of thermal conductivity (CV) is greater than 0.01, the sintered body strength required for use as a heat dissipation component cannot be achieved. The following condition may also be met. 0.80≥MCu / (MCu+MW+MMo)≥0.15

[0049] The following condition may also be met. 0.37≥MCu / (MCu+MW+MMo)≥0.10

[0050] The heat dissipation plate 11 does not necessarily have to contain Mo and can meet the following conditions: MMo=0; and 0.806≥MCu / (MCu+MW)≥0.075.

[0051] If M Cu / (M Cu + M W If the value is less than 0.075, the heat dissipation plate likely has insufficient thermal conductivity. Cu / (M Cu + M W If the coefficient of thermal expansion is greater than 0.806, it is less likely that the coefficient of thermal expansion will match that of the other component, such as the ceramic frame and the mounting plate, and as a result, deformation or cracking may occur. The following condition may also be met: 0.25≥MCu / (MCu+MW)≥0.10

[0052] Alternatively, the heat dissipation plate 11 does not necessarily have to contain W and can meet the following conditions: MW=0 and 0.887≥MCu / (MCu+MMo)≥0.133.

[0053] If M Cu / (M Cu + M Mo If the coefficient of thermal conductivity (Cμ) is less than 0.133, the heat dissipation plate likely has insufficient thermal conductivity. Cu / (M Cu + M Mo If the coefficient of thermal expansion is greater than 0.887, it is less likely that the coefficient of thermal expansion will match that of the other component, such as the ceramic frame and the mounting plate, and as a result, deformation or cracking may occur. The following condition may also be met. 0.37≥MCu / (MCu+MMo)≥0.18

[0054] The remainder of the heat dissipation plate 11, which does not consist of Cu, W, Mo and silicon oxide, can constitute less than 0.5 wt% of the total weight of Cu, W and Mo. In other words, the heat dissipation plate 11 can be composed essentially only of Cu, at least one of W and Mo and silicon oxide.

[0055] Since the numerous silicon oxide particles are dispersed in the heat dissipation plate 11, their particle sizes can be measured by electron microscopy of a cross-section of the heat dissipation plate 11. A specific method for measuring the particle sizes is described below. The particle size distribution obtained by this measurement can satisfy at least one of the following conditions, first to fourth.

[0056] The first condition is that, in the particle size distribution, based on the number of particles in a particle size range of the plurality of silicon oxide particles of 0.2 µm or more and less than 10 µm, the percentage (i.e., the percentage based on the number of particles) of a particle size range of 0.2 µm or more and less than 1.0 µm is 70% or more. In this case, the percentage of silicon oxide particles with a particle size of 10 µm or more in the plurality of silicon oxide particles is preferably 0.1% or less. In other words, the percentage of silicon oxide particles with a particle size of 10 µm or more in the plurality of silicon oxide particles is essentially zero. In other words, the plurality of silicon oxide particles each has a particle size of less than 10 µm.This further reduces concerns that a break in the heat dissipation plate 11 will be caused by the silicon oxide particles.

[0057] The second condition is that, in the particle size distribution, based on the number of particles in a particle size range of 0.2 µm or more and less than 5 µm within the plurality of silicon oxide particles, the percentage of particles in this range must be 70% or more. In this case, the percentage of silicon oxide particles with a particle size of 5 µm or more within the plurality of silicon oxide particles is preferably 0.1% or less. In other words, the percentage of silicon oxide particles with a particle size of 5 µm or more within the plurality of silicon oxide particles is essentially zero. This further reduces concerns about the risk of the heat dissipation plate 11 breaking due to the silicon oxide particles.

[0058] A third condition is that, in the particle size distribution, based on the number of particles in a particle size range of 0.2 µm or more and less than 3 µm within the plurality of silicon oxide particles, the percentage of particles within this range must be 70% or more. In this case, the percentage of silicon oxide particles with a particle size of 3 µm or more within the plurality of silicon oxide particles is preferably 0.1% or less. In other words, the percentage of silicon oxide particles with a particle size of 3 µm or more within the plurality of silicon oxide particles is essentially zero. This further reduces concerns about the risk of the heat dissipation plate 11 breaking due to the silicon oxide particles.

[0059] A fourth condition is that, in the particle size distribution, based on the number of particles in a particle size range of 0.2 µm or more and less than 2 µm within the plurality of silicon oxide particles, the percentage of particles in this range must be 70% or more. In this case, the percentage of silicon oxide particles with a particle size of 2 µm or more within the plurality of silicon oxide particles is preferably 0.1% or less. In other words, the percentage of silicon oxide particles with a particle size of 2 µm or more within the plurality of silicon oxide particles is essentially zero. This further reduces concerns about the risk of the heat dissipation plate 11 breaking due to the silicon oxide particles. (Method for measuring the particle sizes of silicon oxide particles dispersed in the heat dissipation plate)

[0060] First, the heat dissipation plate 11 is cut along its thickness direction. This exposes a cross-section of the heat dissipation plate 11. Ion milling is performed on a region in the center of the cross-section and in its vicinity. An image of the region is acquired using an electron microscope. In the experiments described below, a field emission electron beam microanalyser (FE-EPMA, model: JXA-8500F (from JEOL Ltd.)) was used as the electron microscope under conditions with a measurement magnification of 2000x to 3000x and an accelerating voltage of 15 kV. As can be seen from the Fig.As can be seen in Figures 10 to 12, the white section in the image represents the high-melting-point metal (W and / or Mo), the gray section represents Cu, and the black section represents the silicon oxide particles. The image data is converted into black and white images using image processing software (ImageJ) so that one region of the silicon oxide particles can be distinguished from another. The binarized image data contains a multitude of regions corresponding to the silicon oxide particles. An ellipse fit is performed for each of the regions. Specifically, an ellipse is determined for each region that encompasses the region and has a minimal area. The average of the minor and major axes of the ellipse is calculated as the particle size of each silicon oxide particle. (Method for measuring the silicon oxide content of a heat dissipation plate)

[0061] The areas of the region containing the high-melting-point metal (W and / or Mo), the region containing Cu, and the region containing the silicon oxide particles are calculated from the aforementioned image data by black-and-white binarization using image processing software (ImageJ). The area ratios are considered as volume ratios of the high-melting-point metal (W and / or Mo), Cu, and silicon oxide particles to the heat dissipation plate 11. These volume ratios are then divided by the densities of the respective materials to calculate the weight composition ratios. For example, a density of W of 19.3 g / cm³ is used for the calculation. 3 , a density of Mo of 10.2 g / cm³ 3 , a density of Cu of 8.9 g / cm³ 3 and a density of silicon dioxide (SiO2) of 2.2 g / cm³ 3 used.

[0062] Regarding the composition ratios of the refractory metal (W and / or Mo) and Cu, if the composition ratios of the raw material are already known, the known composition ratios are preferably used, as these are more accurate than the composition ratios based on the image analysis described above. The composition ratios of the raw material are therefore used as the composition ratios of the refractory metal (W and / or Mo) and Cu in the heat dissipation plate 11 (heat dissipation component) in the experiments described below. (Method for manufacturing the housing)

[0063] Fig. Figure 4 is a flowchart that schematically illustrates a process for manufacturing the housing 51 ( Fig. 3) shows. Fig. Figures 5 to 8 are schematic partial cross-sectional views showing steps of the manufacturing process.

[0064] In step ST6 ( Fig.4) At least one of the W-powder and Mo-powder, Cu-powder and SiO2-powder are mixed to form a blended powder. The average particle size of the W-powder and Mo-powder can be 0.5 µm or more and 10 µm or less, preferably 0.5 µm or more and 3 µm or less, and more preferably 0.5 µm or more and 1.5 µm or less. An average particle size of less than 0.5 µm increases the raw material costs, and an average particle size of more than 10 µm makes it difficult to obtain a uniform sintered body due to a difference in specific gravity between the raw materials. The average particle size of copper powder can be 1.5 µm or more and 5.0 µm or less. An average particle size of less than 1.5 µm increases the cost of the raw material.An average particle size greater than 5.0 µm makes it difficult to obtain a uniform sintered body due to the varying specific gravities of the raw materials. The average particle size of SiO2 powder can be 7 nm or more and 200 nm or less, preferably 7 nm or more and 100 nm or less, and more preferably 7 nm or more and 50 nm or less. An average particle size greater than 200 nm makes it difficult to obtain a dense sintered body after sintering. On the other hand, SiO2 powder with an average particle size of less than 7 nm is difficult to produce, so using the powder as a raw material significantly increases the cost of the raw materials for the heat dissipation plate. While SiO2 powder can be crystalline or amorphous, amorphous SiO2 powder is preferred because it is readily available.

[0065] The average particle size of SiO2 powder can be measured using a scanning electron microscope (SEM) image of the SiO2 powder. An ellipse fit, similar to the one described above, is performed on each of a large number of SiO2 powder particles in an image acquired with an SEM at a magnification of approximately 50,000x. The average of the minor and major axes of an ellipse is then calculated as the particle size. For example, the average particle size of 100 particles can be used. The average particle size of tungsten (W) and molybdenum (Mo) powder can be measured using the Fisher method (Japan Tungsten & Molybdenum Industries Association (JP) Standard TMIAS0001:1999 Particle Size Testing Method).The particle size of Cu powder can be measured by laser diffraction and is measured, for example, using a SALD-7500nano nanoparticle size distribution measuring device (from Shimadzu Corporation) after it has been shaken in isopropyl alcohol (IPA) for one minute.

[0066] The mixed powder has a copper content of M Cu(P) wt.%, a tungsten content of M W(P) wt.%, a molybdenum content of M Mo(P) wt% and a silicon oxide content of M SiO2(P) wt.%, based on SiO2 equivalent, relative to the total weight of Cu, Mo and W, and fulfills: 0.9≥MCu(P) / (MCu(P)+MW(P)+MMo(P))≥0.045 and 0.03≥MSiO2(P) / (MCu(P)+MW(P)+MMo(P))≥0.001.

[0067] The mixing step mentioned above can include a first step to mix Cu powder and SiO2 powder to obtain a Cu-SiO2 mixed powder, and a second step to mix the Cu-SiO2 mixed powder with at least one of W powder and Mo powder. In this case, the proportion of SiO2 powder present on the surfaces of the Cu powder particles in the final mixed powder can be increased. The mixing step mentioned above can be carried out, for example, using a ball mill. After the mixing step, only the mixed powder can be isolated. However, isolation is not strictly necessary, and the mixed powder can, for example, form a suspension together with a solvent, a dispersant, a plasticizer, and the like. The suspension can be a raw material for green sheets or a shaped body as described below.

[0068] In step ST11 ( Fig.4) A large number of green panels LG1 to LG9 (see below) will be used. Fig. 6) formed, which by firing to the heat dissipation plate 11 ( Fig. 3) become. While a structure that becomes a heat dissipation plate 11 through firing, in Fig.Since a laminate body is composed of nine green plates, the number of green plates is not particularly limited. Green plates LG1 to LG9 contain the mixing powder and a resin. Green plates LG1 to LG9 can be formed by dividing a single green plate. A known, typical method can be used to form the green plates from the mixing powder. To describe this by way of an example, a slurry is first prepared. The slurry is obtained by mixing the powder, which is to be a component of the sintered body, with the resin, suspension, solvent, and the like, using a ball mill. The slurry is processed into green plates by a doctor blade process. The planar shapes of the green plates are determined according to the shape of a target component. The planar shapes of the green plates for forming the heat dissipation plate 11 are typically rectangular.

[0069] In step ST13 ( Fig. 4) a ceramic frame green plate 21G is formed, which is fired to form a ceramic frame 21 ( Fig. 3) is. Examples of powders for forming the ceramic frame green plate 21G include Al2O3 powder as the main component and SiO2 powder as a sintering aid. The planar form of the ceramic frame green plate 21G is a frame shape obtained by removing a section corresponding to the cavity CV ( Fig. 3) of the ceramic frame 21. In particular, the ceramic frame green plate 21G, after being formed as a simple plate by a doctor blade process, is shaped by removing the section corresponding to the cavity CV.

[0070] In step ST20 ( Fig. 4) The green panels LG1 to LG9 and the ceramic frame green panel 21G are laminated to form a laminate body SG ( Fig. 5 and Fig.6) The laminate body SG contains a laminate body 11G, which is formed by laminating the green plates LG1 to LG9. The laminate body 11G is then fired to form the heat dissipation plate 11 ( Fig. 3).

[0071] Next, at a position where the breaking described below is carried out, a trench (not shown) can be machined into a surface of each of the laminate bodies 11G and the ceramic frame green plate 21G by machining using CT cutting edges ( Fig. 5) and laser processing using a laser processing device (not shown).

[0072] In step ST30 ( Fig. 4) the laminate body SG ( Fig. 5) fired. The green panels LG1 to LG9 and the ceramic frame green panel 21G are thus fired. The aforementioned mixed powder is thus fired. Through firing, the laminate body SG is transformed into the fired body SF ( Fig.7) converted. The firing temperature is, for example, 1100°C or more and 1400°C or less. A firing temperature of 1100°C or more allows the laminate body SG to be heated to a temperature equal to or above the melting point of Cu. In other words, the aforementioned mixed powder can be heated to a temperature equal to or above the melting point of Cu. The Cu-containing heat dissipation plate 11 can thus be manufactured to a high standard. On the other hand, a firing temperature of 1400°C or less avoids a difficulty in one step caused by an excessively high firing temperature.

[0073] Next, a break step is carried out starting from the aforementioned trench, as indicated by the dashed lines BR ( Fig.7) shown. This divides the fired body SF into a multitude of sections. In this way, a multitude of fired bodies SF are obtained, which form a multitude of casings 51 ( Fig. 3) correspond ( Fig. 8).

[0074] Next, the ladder frame 30 ( Fig. 3) SF is attached to each of the fired bodies. In this way, the casing 51 ( Fig. 3) received.

[0075] In the aforementioned manufacturing process, the coating can be carried out at a suitable time after the firing step. The aforementioned manufacturing process is an example, as described above, and various modifications are applicable. For example, cutting on the laminate body SG can be performed before firing, instead of performing the fracturing step on the fired body SF. While the semiconductor element 8 ( Fig.2) If, according to the aforementioned manufacturing process, the application is to take place at a time after the crushing step, the application may not take place at that time, but at a time after the firing step and before the crushing step.

[0076] Since the heat dissipation plate 11 in the aforementioned manufacturing process comprises the laminated body 11G made of a multitude of green sheets, a heat dissipation plate 11 with a large thickness can easily be produced by increasing the number of laminated green sheets. Alternatively, as a modification, the heat dissipation plate 11 can comprise a single green sheet, in which case the manufacturing process is simplified. Another modification involves a manufacturing process that does not include a step for forming a green sheet. For example, a molded body can be formed by compression molding powder instead of forming the green sheet. The resulting molded body is then fired, allowing the heat dissipation component to be obtained without forming the green sheet. An additive can be added to the mixed powder to be compression molded to facilitate the compression molding process.The additive is typically a material that essentially disappears at the end of the firing process and is, for example, a solvent, a dispersant, a plasticizer, a resin, or a combination thereof. (Effects)

[0077] According to the present embodiment, the heat dissipation plate 11 tends to exhibit good thermal conductivity properties due to its Cu content, and its content of at least one of W and Mo allows for adjustment of the coefficient of thermal expansion. Furthermore, the elastic modulus can be dampened by the silicon oxide content, while a significant impairment of the thermal conductivity properties can be avoided by keeping the amount of silicon oxide to a minimum.Among various materials such as silicon dioxide, aluminum oxide, zirconium oxide, and titanium oxide, which are typical ceramic materials for achieving a ceramic structure, silicon dioxide exhibits a low modulus of elasticity and a low coefficient of thermal expansion as a material for particles dispersed in the sintered material section of the heat dissipation plate 11, making silicon dioxide a preferred material for achieving the aforementioned effect. While silicon dioxide can be crystalline or amorphous after firing, amorphous silicon dioxide is more desirable because of its lower modulus of elasticity and lower coefficient of thermal expansion.Accordingly, the reduction in the reliability of the connection or ceramic frame 21 (component made of a different material) to be connected to the heat dissipation plate 11, caused by the difference in thermal expansion compared to the ceramic frame 21 (component made of a different material), can be suppressed, while the heat dissipation plate 11 has a similar coefficient of thermal expansion to the ceramic material and good thermal conductivity.

[0078] In the particle size distribution of the silicon oxide particles, the percentage of a particle size range of 0.2 µm or more and less than 1.0 µm is preferably 70% or more, as described above. According to the inventor's investigations, the effect of reducing the elastic modulus of the heat dissipation plate 11 is particularly pronounced when the silicon oxide particles each have a particle size within a range of 0.2 µm or more and less than 1.0 µm. Silicon oxide particles with excessively large particle sizes presumably have only a minor effect on reducing the elastic modulus. In fact, there is a concern that silicon oxide particles with excessively large particle sizes could lead to the heat dissipation plate 11 breaking.

[0079] The heat dissipation plate 11 ( Fig.3) can have a side surface P4b that is flush with the outer surface P4a of the ceramic frame 21. A section of the side surface P4b can be a fractured surface obtained in the fracture step ( Fig.7) In this case, the base area (the area of ​​a region in which the semiconductor element 8 and the like can be mounted) can be easily secured, while a fracture of the housing 51 originating from a section between the outer surface P4a and the side surface P4b is avoided. A typical case in which the side surface P4b is not flush with the outer surface P4a involves a case in which the outer surface P4a projects outwards from the side surface P4b, or a case in which the outer surface P4a is located within the side surface P4b. In the former case, the fracture can originate from the projection. In the latter case, the outer edge of the ceramic frame 21 is located inwards, so that an inner edge of the ceramic frame 21 is also located inwards, as long as the width of the ceramic frame 21 must be limited to a predetermined dimension, thereby reducing the base area. <Ausführungsform 2>

[0080] Fig. Figure 9 is a schematic cross-sectional view showing a configuration of a semiconductor module 92 according to embodiment 2. The semiconductor module 92 has a configuration in which the housing 51 of the semiconductor module 91 ( Fig. 2: In embodiment 1) the ceramic frame 29 was replaced by a housing 52 according to embodiment 2. The housing 52 includes the ceramic frame 29 and the brazing layer 26 (bonding layer) instead of the ceramic frame 21 ( Fig. 2: Embodiment 1). The ceramic frame 29 is made of ceramic, and the ceramic is typically aluminum oxide. The brazing material layer 26 is, for example, a silver brazing material. Preferably, a metallization layer (not shown) is arranged on a surface of the ceramic frame 29 that faces the brazing material layer 26. A resin adhesive layer can be used as the bonding layer instead of the brazing material layer 26. <Ausführungsform 3>

[0081] The heat dissipation plate 11 ( Fig. 3), to which the ceramic frame 21 was not attached, can be produced. For example, in the method described above in embodiment 1 for producing the fired body SF ( Fig. 7) the formation of the ceramic frame green panel 21G ( Fig. 5) omitted, so that the heat dissipation plate 11 is obtained, to which no other component, such as the ceramic frame 21, has been attached. A further plate can be attached to the heat dissipation plate 11 thus obtained, and by attaching the ceramic frame 29 and the like, the housing 52 ( Fig. 9: embodiment 2) can be obtained. As a modification, a shaped body can be formed by pressing instead of forming a green plate, as described in embodiment 1. <Ausführungsform 4>

[0082] Fig.Figure 17 is a schematic cross-sectional view showing a configuration of a semiconductor module 94 according to embodiment 4. Fig. Figure 18 is a schematic cross-sectional view showing a configuration of a heat dissipation substrate 54 as a component of the semiconductor module 94 in Fig. 17 shows.

[0083] The semiconductor module 94 includes the heat dissipation substrate 54 and the semiconductor element 8 mounted thereon. The heat dissipation substrate 54 includes the heat dissipation plate 11 and a ceramic insulating layer 24, which is arranged on the main surface P2 of the heat dissipation plate 11. The heat dissipation substrate 54 includes a conductor layer 34 arranged on the ceramic insulating layer 24. The conductor layer 34 is electrically insulated from the heat dissipation plate 11 by the ceramic insulating layer 24. The semiconductor element 8 is mounted on the conductor layer 34. A bonding material 291 can be used for fastening. A bonding wire and the like can be connected to the conductor layer 34.

[0084] In embodiment 4, the heat dissipation plate 11 preferably has a thickness of 0.3 mm or more and 3.0 mm or less, and more preferably a thickness of 0.5 mm or more and 1.5 mm or less. Too little thickness results in insufficient mechanical strength of the heat dissipation plate 11. Too much thickness results in excessive thermal resistance. The ceramic insulating layer 24 has a lesser thickness than the heat dissipation plate 11. The ceramic insulating layer 24 preferably has a thickness of 5 µm or more and 50 µm or less, and more preferably a thickness of 5 µm or more and 20 µm or less. Too little thickness can lead to problems with thickness variation in the ceramic insulating layer 24. In particular, the electrical insulation in a section with locally low thickness is likely to be insufficient. Too much thickness results in excessive thermal resistance.The conductive layer 34 has a thinner profile than the heat dissipation plate 11. The conductive layer 34 preferably has a thickness of 5 µm or more and 200 µm or less, and more preferably a thickness of 5 µm or more and 20 µm or less. Too thin a layer can lead to problems due to variations in the thickness of the conductive layer 34. Too thick a layer leads to excessive thermal resistance.

[0085] The ceramic insulating layer 24 is composed of ceramic. The ceramic may contain aluminum oxide (Al₂O₃) as the main component, may contain a trace amount of silicon dioxide (SiO₂) to promote sintering of the ceramic, and may contain an additive containing a manganese element. It may also contain another component. For example, a material for the ceramic insulating layer 24 may be a mixed powder consisting of 50 wt.% or more Al₂O₃ powder as the main component, 5 wt.% to 17 wt.% silicon-containing powder (based on SiO₂ equivalent), and 3 wt.% to 14 wt.% manganese-containing powder (based on MnO equivalent). The firing temperature when using the mixed powder is, for example, 1150°C to 1300°C.

[0086] The conductive layer 34 can contain Cu and at least one high-melting-point metal selected from the group consisting of W and Mo. If the total volume of the conductive layer 34 is defined as 100 vol%, the conductive layer 34 can contain 30 vol% or less of ceramic. The ceramic is, for example, composed of aluminum oxide. Other ceramics can be included together with or instead of aluminum oxide, and, for example, SiO₂ and / or MnO₂ can be included. The conductive layer 34 contains ceramic to improve the adhesion between the conductive layer 34 and the ceramic insulating layer 24. The ceramic can contain fine silicon oxide particles with an average particle size of 5 nm or more and 200 nm or less. The conductive layer 34 described above and the heat dissipation plate 11 can be formed from a common material. However, they can also be formed from different materials for any reason.

[0087] Fig. Figure 19 is a schematic partial cross-sectional view showing one step of a process for producing the heat dissipation substrate 54. In this step, a laminate body SG4 including the laminate body 11G is used instead of the laminate body SG ( Fig.6: In embodiment 1), the laminate body SG4 is formed including the laminate body 11G. As in embodiment 1, a single green plate can be used instead of the laminate body 11G. The laminate body SG4 further includes a green plate 24G, which is transformed into a ceramic insulating layer 24 by firing. A ceramic paste layer, which is transformed into a ceramic insulating layer by firing, can be formed by printing instead of laminating the green plate 24G onto the laminate body 11G. The laminate body SG4 further includes a green plate 34G, which is transformed into a conductor layer 34 by firing. A conductor paste layer, which is transformed into a conductor layer 34 by firing, can be formed by printing instead of the green plate 34G. The heat dissipation substrate 54 is obtained by firing the laminate body SG4.

[0088] Any configuration other than the one mentioned above is essentially the same as the configuration mentioned above according to embodiment 1, such that identical or corresponding elements bear the same reference numerals and their description is not repeated. <Beispiele und Vergleichsbeispiele>

[0089] A single heat dissipation component, such as the heat dissipation plate 11 according to embodiment 3, was manufactured and evaluated. Table 1 below lists the raw material composition, i.e., the composition of the mixed powder, the particle size of the raw material, and the method for introducing Cu. [Table 1] RAW MATERIAL COMPOSITION [wt.%] RAW MATE RIAL Particle Size [µm] Copper insertion process SUBTOTAL 100 wt.% SiO2 W, Mo SiO2 Cu W Mon Comparative example 1 11,0 89,0 0,0 0,0 1,5 - IMPREGNATION Comparative example 2 20,0 80,0 0,0 0,0 1,5 - IMPREGNATION Comparative example 3 30,0 0,0 70,0 0,0 1,5 - IMPREGNATION Comparative example 4 60,0 0,0 40,0 0,0 1,5 - IMPREGNATION Comparative example 5 30,0 0,0 70,0 0,1 1,5 1,5 POWDER MIXING Example 1 7,5 92,5 0,0 0,1 0,8 0,017 POWDER MIXING Example 2 16,5 83,5 0,0 0,5 0,8 0,017 POWDER MIXING Example 3 27,4 72,6 0,0 0,8 0,8 0,017 POWDER MIXING Example 4 31,6 68,4 0,0 0,1 0,8 0,017 POWDER MIXING Example 5 31,6 68,4 0,0 0,5 0,8 0,017 POWDER MIXING Example 6 31,6 68,4 0,0 1,0 0,8 0,017 POWDER MIXING Example 7 31,6 68,4 0,0 2,0 0,8 0,017 POWDER MIXING Example 8 31,6 68,4 0,0 3,0 0,8 0,017 POWDER MIXING Comparative example 6 31,6 68,4 0,0 4,0 0,8 0,017 POWDER MIXING Example 9 41,0 59,0 0,0 1,2 0,8 0,017 POWDER MIXING Example 10 64,8 35,2 0,0 1,9 0,8 0,017 POWDER MIXING Example 11 80,6 19,4 0,0 2,4 0,8 0,017 POWDER MIXING Example 12 13,3 0,0 86,7 0,5 1,5 0,017 POWDER MIXING Example 13 46,5 0,0 53,5 1,0 1,5 0,017 POWDER MIXING Example 14 88,7 0,0 11,3 1,0 1,5 0,017 POWDER MIXING

[0090] Amorphous silicon dioxide was used. In the "Cu Introduction Method" column of Table 1 above, "Impregnation" means that copper was introduced into a porous body of tungsten or molybdenum by impregnation. "Powder Mixing" means that copper powder was added in a powder mixing step to produce the powder to be fired. The firing temperature during firing was 1250°C.

[0091] While the composition of the heat dissipation component is given in Table 1 above relative to the total weight of Cu, W and Mo, it is given in Table 2 below relative to the total weight of Cu, W, Mo and silicon dioxide (SiO2). [Table 2] RAW MATERIAL COMPOSITION [wt.%] SUBTOTAL 100 wt.% Cu W Mon SiO2 Comparative example 1 11,0 89,0 0,0 0,0 Comparative example 2 20,0 80,0 0,0 0,0 Comparative example 3 30,0 0,0 70,0 0,0 Comparative example 4 60,0 0,0 40,0 0,0 Comparative example 5 30,0 0,0 69,9 0,1 Example 1 7,5 92,4 0,0 0,1 Example 2 16,4 83,1 0,0 0,5 Example 3 27,2 12,0 0,0 0,8 Example 4 31,5 68,4 0,0 0,1 Example 5 31,4 68,1 0,0 0,5 Example 6 31,2 67,8 0,0 1,0 Example 7 30,9 67,1 0,0 2,0 Example 8 30,6 66,4 0,0 2,9 Comparative example 6 30,3 65,8 0,0 3,8 Example 9 40,5 58,3 0,0 1,2 Example 10 63,6 34,5 0,0 1,9 Example 11 78,7 18,9 0,0 2,4 Example 12 13,2 0,0 86,3 0,5 Example 13 46,0 0,0 53,0 1,0 Example 14 87,8 0,0 11,2 1,0

[0092] The composition and evaluation result of a heat dissipation component obtained using the aforementioned raw materials are shown in Table 3 below. [Table 3] AFTERBURNING COMPOSITION [wt.%] SILICON OXIDE Particle Size Distribution [µm] SINTERED STATE COEFFICIENT OF THERMAL EXPANSION [ppm / K] Stress at elongation 1% [MPa] SUBTOTAL 100 wt.- % SiO2 Cu W Mon 0,2-1,0 1,0-2,0 Comparative example 1 11,0 89,0 0,0 0,0 - - SUFFICIENT 6,5 65 Comparative example 2 20,0 80,0 0,0 0,0 - - SUFFICIENT 7,9 77 Comparative example 3 30,0 0,0 70,0 0,0 - - SUFFICIENT 7,7 67 Comparative example 4 60,0 0,0 40,0 0,0 - - SUFFICIENT 11,5 46 Comparative example 5 30,0 0,0 70,0 0,10 10 % 90 % NOT SUFFICIENT - - Example 1 7,5 92,5 0,0 0,03 70 % 30 % SUFFICIENT 6,9 40 Example 2 16,5 83,5 0,0 0,17 79 % 21 % SUFFICIENT 9,1 35 Example 3 27,4 72,6 0,0 0,28 77 % 23 % SUFFICIENT 11,3 32 Example 4 31,6 68,4 0,0 0,03 72 % 28 % SUFFICIENT 12,1 32 Example 5 31,6 68,4 0,0 0,17 81 % 19% SUFFICIENT 12,1 31 Example 6 31,6 68,4 0,0 0,34 85 % 15% SUFFICIENT 12,0 30 Example 7 31,6 68,4 0,0 0,68 88 % 12% SUFFICIENT 11,8 30 Example 8 31,6 68,4 0,0 1,01 89% 11 % SUFFICIENT 11,5 29 Comparative example 6 31,6 68,4 0,0 1,34 89% 11 % NOT SUFFICIENT - - Example 9 41,0 59,0 0,0 0,42 80 % 20 % SUFFICIENT 13,3 23 Example 10 64,8 35,2 0,0 0,66 85 % 15 % SUFFICIENT 16,5 15 Example 11 80,6 19,4 0,0 0,82 88 % 12% SUFFICIENT 17,5 13 Example 12 13,3 0,0 86,7 1,29 81 % 19% SUFFICIENT 7,8 40 Example 13 46,5 0,0 53,5 0,73 86 % 14% SUFFICIENT 12,6 23 Example 14 88,7 0,0 11,3 0,38 86 % 14% SUFFICIENT 18,0 15

[0093] According to the inventor's preliminary study, the change in the composition of the heat dissipation component from the raw material composition (composition of the mixed powder) to the composition after firing (composition of the heat dissipation component) was sufficiently small for Cu, W, and Mo. The raw material composition values ​​shown in Table 1 were therefore used for these elements. On the other hand, the silicon oxide content in the cross-section of the heat dissipation component, estimated from the electron micrograph described above at 2000x magnification, was significantly reduced compared to the silicon oxide content in the mixed powder. For confirmation, a reflected electron micrograph at 25,000x magnification was performed, but no silicon oxide particles other than those visible in the aforementioned electron micrograph were observed.Qualitative analysis using an electron beam microanalyzer (EPMA) revealed no significant silicon elements in a region where no silicon oxide particles were observed. It is therefore assumed that silicon oxide leaches from the heat dissipation component during firing. The silicon oxide content after firing was thus calculated using the image data from the electron micrograph described above. The content is given in SiO₂ equivalents.

[0094] Referring to Table 3, in Comparative Example 5 the sintered state was insufficient, i.e., the sintered body was not dense and exhibited many pores. This is presumably related to the particle size of the SiO2 powder added during fabrication. Although the exact reason is unknown, this phenomenon occurs when the SiO2 powder has a particle size greater than 200 nm. Although not listed in Table 3, similar results were obtained when Mo was replaced by W in Comparative Example 5.

[0095] In comparative examples 1 to 4, Cu elements were introduced by impregnation, in contrast to the present embodiment.

[0096] "SILIUM OXIDE PARTICLE SIZE DISTRIBUTION" refers to the particle size distribution based on the number of particles determined by electron microscopy of the silicon oxide particles. Specifically, "0.2-1.0" denotes a percentage of a particle size range of 0.2 µm or more and less than 1.0 µm, and "1.0-2.0" denotes a percentage of a particle size range of 1.0 µm or more and less than 2.0 µm. The results show that in the particle size distribution based on the number of particles in a particle size range of 0.2 µm or more and less than 2.0 µm, the percentage of a particle size range of 0.2 µm or more and less than 1.0 µm was 70% or more in each of the examples.In addition to the inventor's investigation, in the particle size distribution based on the number of particles in a particle size range of 0.2 µm or more and less than 3.0 µm, the percentage of particles in a size range of 0.2 µm or more and less than 1.0 µm was 70% or more in each of the examples. In addition to this study, in the particle size distribution based on the number of particles in a particle size range of 0.2 µm or more and less than 5.0 µm, the percentage of particles in a size range of 0.2 µm or more and less than 1.0 µm was 70% or more in each of the examples. In addition to this study, the percentage of the particle size range of 0.2 µm or more and less than 1.0 µm in the particle size distribution, based on the number of particles in a particle size range of 0.2 µm or more and less than 10 µm, was 70% or more in each of the examples.

[0097] In each of the examples, the silicon oxide particles of the heat dissipation component had a particle size of less than 10 µm. The number of silicon oxide particles with a particle size of 10 µm or more is preferably small and more preferably essentially zero. This can further reduce concerns that a breakage of the heat dissipation plate 11 will be caused by the silicon oxide particles. In addition to the inventor's study, the silicon oxide particles of the heat dissipation component in each of the examples had a particle size of less than 5.0 µm. The number of silicon oxide particles with a particle size of 5.0 µm or more is preferably small and more preferably essentially zero. This can further reduce concerns that a breakage of the heat dissipation plate 11 will be caused by the silicon oxide particles.In addition to the study, the silicon oxide particles of the heat dissipation component in each of the examples had a particle size of less than 3.0 µm. The number of silicon oxide particles with a particle size of 3.0 µm or more is preferably small and more preferably essentially zero. This can further reduce the concern that the failure of the heat dissipation plate 11 is caused by the silicon oxide particles. In addition to this study, the silicon oxide particles of the heat dissipation component in each of the examples had a particle size of less than 2.0 µm. The number of silicon oxide particles with a particle size of 2.0 µm or more is preferably small and more preferably essentially zero. This can further reduce the concern that the failure of the heat dissipation plate 11 is caused by the silicon oxide particles.

[0098] In Table 3 above, the "SINTERING STATE" column indicates the result of the assessment of whether a sintering state suitable for use as a heat dissipation component was achieved. The "COEFFICIENT OF THERMAL EXPANSION" was calculated based on the thermal expansion between room temperature and 100°C. A stress value at strain of 1% was measured as an indicator of the modulus of elasticity. It follows that the lower the stress value, the lower the modulus of elasticity. The stress value at strain was measured using a strain gauge in a three-point bending test according to JISR 1602.

[0099] The Fig. 10, Fig. 11 and Fig.Figures 12 are electron microscope images of cross-sections of the heat dissipation components in Example 2, Example 3, and Example 9, respectively. In each of these microscope images, the white section is tungsten, the gray section is copper, and the black section represents the silicon oxide particles. The silicon oxide in Examples 1 through 14 was amorphous silicon oxide. Fig. 13(a) and Fig. Figure 13(b) shows the relationship between the copper content and the stress at a strain of 1%. For each of the diagrams in Fig. 13(a) Cu- and W-containing heat dissipation plates shown and in each of the in Fig. In the Cu- and Mo-containing heat dissipation plates shown in Figure 13(b), the stress at 1% strain was lower in each of the examples (filled circles) than in each of the comparison examples (triangles). Fig. 14(a) and Fig.Figure 14(b) shows diagrams that each illustrate a relationship between the coefficient of thermal expansion and the stress at 1% strain. For example, when comparing data with the same coefficient of thermal expansion, the stress value in each of the examples (filled circles) was lower than in each of the comparison examples (triangles).

[0100] Fig. Figure 15 is a diagram schematically showing the fine structure of a heat dissipation component containing Cu and W, in which no silicon oxide particles are dispersed. In this structure, Cu has penetrated the cavity between the sintered W particles. In this case, it is likely that W particles with a high modulus of elasticity are directly bonded to each other. Consequently, the heat dissipation component exhibits a high modulus of elasticity. In contrast, Fig.Figure 16 shows a diagram schematically depicting the fine structure of a heat dissipation component containing Cu and W, in which silicon oxide particles are dispersed. In this structure, fine silicon oxide particles are located between the W particles to disrupt the direct bonding of the W particles with their high elastic modulus, and Cu with its low elastic modulus is likely to penetrate between the W particles. This reduces the elastic modulus of the heat dissipation component. While this effect caused by the silicon oxide particles is sufficiently achieved, the silicon oxide content can be suppressed to such an extent that the silicon oxide particles do not have a significant negative impact on the thermal conductivity of the heat dissipation component, since the silicon oxide particles are fine particles. The same applies to a case where Mo particles are used instead of W particles in the Fig. 15 and Fig. 16 can be used.

[0101] While the composition of the heat dissipation component is given in Table 3 above relative to the total weight of Cu, W and Mo, it is given in Table 4 below relative to the total weight of Cu, W, Mo and silicon dioxide (SiO2).

[0102] [Table 4] COMPOSITION AFTER BURNING [wt.%] SUBTOTAL 100 wt.% Cu W Mon SiO2 Comparative example 1 11,0 89,0 0,0 0,0 Comparative example 2 20,0 80,0 0,0 0,0 Comparative example 3 30,0 0,0 70,0 0,0 Comparative example 4 60,0 0,0 40,0 0,0 Comparative example 5 30,0 0,0 69,9 0,1 Example 1 7,5 92,5 0,0 0,0 Example 2 16,5 83,4 0,0 0,2 Example 3 27,3 72,4 0,0 0,3 Example 4 31,5 68,4 0,0 0,0 Example 5 31,5 68,3 0,0 0,2 Example 6 31,5 68,2 0,0 0,3 Example 7 31,3 68,0 0,0 0,7 Example 8 31,2 67,8 0,0 1,0 Comparative example 6 31,1 67,5 0,0 1,3 Example 9 40,8 58,8 0,0 0,4 Example 10 64,4 34,9 0,0 0,7 Example 11 79,9 19,2 0,0 0,8 Example 12 13,3 0,0 85,6 0,2 Example 13 46,3 0,0 53,1 0,3 Example 14 88,4 0,0 11,3 0,3 Reference symbol list

[0102] EXPLANATION OF THE REFERENCE SYMBOLS 11 Heat dissipation plate (heat dissipation component) 11G, SG laminate body 21, 29 ceramic frames 21G ceramic frame green plate 24 ceramic insulating layer 26 layers of brazing material 34 conductor layer 51, 52 Case 54 Heat dissipation substrate LG1-LG9 Green plate SF Burnt Body QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2015-204426

[0003] JP 2015-204426

[0007]

Claims

[1] Heat dissipation component, comprising: a sintered material section containing copper and at least one of tungsten and molybdenum; and a large number of silicon oxide particles dispersed in the sintered material section, wherein the heat dissipation component has a copper content of M Cu weight percent, a tungsten content of M W weight percent, a molybdenum content of M Mo weight percent and a silicon oxide content of M SiO2 weight percent, based on SiO2 equivalent, relative to the total weight of copper, tungsten and molybdenum, wherein the heat dissipation component fulfills 0.9≥MCu / (MCu+MW+MMo)≥0.045 and 0.01≥MSiO2 / (MCu+MW+MMo)≥0.0003. [2] Heat dissipation component according to claim 1, wherein in the particle size distribution, based on the number of particles in a particle size range of the plurality of silicon oxide particles of 0.2 µm or more and less than 10 µm, the percentage fraction of a particle size range of 0.2 µm or more and less than 1.0 µm is 70% or more. [3] Heat dissipation component according to claim 2, wherein the plurality of silicon oxide particles each have a particle size of less than 10 µm. [4] Heat dissipation component according to claim 1, wherein in the particle size distribution, based on the number of particles in a particle size range of the plurality of silicon oxide particles of 0.2 µm or more and less than 5 µm, the percentage fraction of a particle size range of 0.2 µm or more and less than 1.0 µm is 70% or more. [5] Heat dissipation component according to claim 4, wherein the plurality of silicon oxide particles each have a particle size of less than 5 µm. [6] Heat dissipation component according to claim 1, wherein in the particle size distribution, based on the number of particles in a particle size range of the plurality of silicon oxide particles of 0.2 µm or more and less than 3 µm, the percentage proportion of a particle size range of 0.2 µm or more and less than 1.0 µm is 70% or more. [7] Heat dissipation component according to claim 6, wherein the plurality of silicon oxide particles each have a particle size of less than 3 µm. [8] Heat dissipation component according to claim 1, wherein in the particle size distribution, based on the number of particles in a particle size range of the plurality of silicon oxide particles of 0.2 µm or more and less than 2 µm, the percentage fraction of a particle size range of 0.2 µm or more and less than 1.0 µm is 70% or more. [9] Heat dissipation component according to claim 8, wherein the plurality of silicon oxide particles each have a particle size of less than 2 µm. [10] Heat dissipation component according to any one of claims 1 to 9, wherein the heat dissipation component fulfills 0.08≥MCu / (MCu+MW+MMo)≥0.

15. [11] Heat dissipation component according to any one of claims 1 to 9, wherein a remainder of the heat dissipation component, which is different from copper, tungsten, molybdenum and silicon oxide, constitutes less than 0.5 percent by weight, relative to the total weight. [12] Heat dissipation component according to any one of claims 1 to 9, wherein the heat dissipation component fulfills: MMo=0 and 0.806 ≥MCu / (MCu+MW)≥0.

075. [13] Heat dissipation component according to any one of claims 1 to 9, wherein the heat dissipation component fulfills: MW=0; and 0.887≥MCu / (MCu+MMo)≥0.

133. [14] Heat dissipation component manufacturing method according to any one of claims 1 to 9, wherein the heat dissipation component manufacturing method comprises: Mixing at least one of tungsten powders with an average particle size of 0.5 µm or more and 10 µm or less, molybdenum powders with an average particle size of 0.5 µm or more and 10 µm or less, copper powders with an average particle size of 1.5 µm or more and 5.0 µm or less, and SiO2 powders with an average particle size of 7 nm or more and 200 nm or less to form a mixed powder, wherein the mixed powder has a copper content of M Cu(P) weight percent, a tungsten content of M W(P) weight percent, a molybdenum content of M Mo(P) weight percent and a silicon oxide content of M SiO2(P) weight percent in terms of SiO2 equivalent, relative to the total weight of copper, tungsten and molybdenum, wherein the mixed powder meets 0.9≥MCu(P) / (MCu(P)+MW(P)+MMo(P))≥0.045 and 0.03≥MSiO2(P) / (MCu(P)+MW(P)+MMo(P))≥0.001; and Heating the mixed powder to a temperature at or above the melting point of copper. [15] Heat dissipation component manufacturing method according to claim 14, further comprising the forming of at least one green plate containing the mixing powder and a resin, wherein The burning of the mixed powder is carried out by burning at least one green plate. [16] Heat dissipation component manufacturing method according to claim 15, wherein the at least one green plate comprises a plurality of green plates, the manufacturing method further comprising the lamination of the multitude of green panels to form a laminate body, whereby The burning of the mixed powder is carried out by burning the laminate body. [17] Housing, comprising: the heat dissipation component according to any one of claims 1 to 9; and a ceramic frame, wherein the heat dissipation component has a heat dissipation surface and a main surface opposite the heat dissipation surface, and the ceramic frame is arranged on the main surface of the heat dissipation component and has an inner surface surrounding a cavity and an outer surface opposite the inner surface. [18] Substrate, comprising: the heat dissipation component according to one of claims 1 to 9; and a ceramic insulating layer, wherein the heat dissipation component has a heat dissipation surface and a main surface opposite the heat dissipation surface, and the ceramic insulating layer is arranged on the main surface of the heat dissipation component.

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