Electronic component mounting fixture

Abstract

To provide a fixture for electronic component fitting strong against oxidation, having heat resistance and having satisfactory workability.SOLUTION: A fixture for electronic component fitting for mounting an electronic component and heating the same is composed of an aggregate part made of SiC, and a cavity part, and a surface thereof has an electronic component mounting face.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a jig for mounting electronic components. [Background technology]

[0002] In recent years, the electrification of automobiles and the frequency control of various motors have progressed, and power devices such as IGBTs, GTOs, and FETs have become widely used. In recent years, SiC has been attracting attention as a power device. Compared to conventional silicon, SiC has a higher dielectric breakdown strength and a larger band gap, which gives it the ability to withstand high voltages, have low resistance, and have low losses, and it is beginning to be used widely. In addition, the maximum operating temperature of SiC is extremely high at 300 to 400°C compared to 150°C for conventional Si devices, and the device itself also has high thermal conductivity, making it an advantageous device in terms of heat.

[0003] Such devices cannot be used by themselves, but can only be used by electrically connecting them to a lead frame or the like and then encasing them in a glass, metal case, or ceramic package. Patent Document 1 describes a graphite jig that prevents the occurrence of carburization in the manufacture of such devices, as "a carbon-graphite jig in which the intensity ratio O1S / C1S of the area intensity of the O1S band to the area intensity of the C1S band on the carbon-graphite substrate surface in X-ray photoelectron spectroscopy (ESCA) is 0.10 or more, and the carbon-graphite substrate contains impurities of 800 ppm or less and each of the elements Fe, Co, and Ni of 60 ppm or less." Such graphite jigs are widely used because they are easy to process, do not react with devices, and are heat resistant. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 5-319929 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the invention described above, the jig is made of graphite, and therefore must be used in an inert atmosphere. Even if used in an inert atmosphere, small amounts of oxygen or adsorbed moisture can cause gradual oxidation, resulting in the generation of graphite particles and wear.

[0006] In view of the above problems, an object of the present invention is to provide a jig for mounting electronic components that is resistant to oxidation, heat resistant, and easy to process. [Means for solving the problem]

[0007] In order to solve the above problems, the electronic component mounting jig of the present invention is an electronic component mounting jig for mounting and heating an electronic component, comprising: The electronic component mounting jig is characterized in that it is composed of a framework portion made of SiC and a hollow portion, and has an electronic component mounting surface on its surface.

[0008] According to the electronic component mounting jig of the present invention, since the jig itself is made of SiC, it has high heat resistance and oxidation resistance. In addition, since it is not made of solid SiC but is made of a cavity and an aggregate, it is easy to process because only the aggregate needs to be processed to obtain a desired shape, and it can be suitably used as an electronic component mounting jig.

[0009] In the electronic component mounting jig of the present invention, the framework portion is preferably a porous body. When the aggregate portion is porous, chipping is less likely to occur during processing, and an electronic component mounting jig with high dimensional accuracy can be obtained.

[0010] In the electronic component mounting jig of the present invention, the framework portion preferably has a porosity of 35 to 65%. When the porosity of the aggregate portion is 35% or more, it can be easily processed, and when the porosity of the aggregate portion is 65% or less, it can have sufficient strength to maintain the overall shape.

[0011] In the electronic component mounting jig of the present invention, the cavity is preferably connected to the outer surface. Because the hollow portion is connected to the outer surface, gases, flux, brazing material vapor, and other substances generated by the reaction between the electronic components and SiC do not remain in the gap between the electronic component mounting jig and the electronic components, but are quickly diffused to the outside.

[0012] In the electronic component mounting jig of the present invention, the framework portion preferably has a honeycomb shape. Since the aggregate portion has a honeycomb shape, it has high strength and has low resistance to gas passage, so that generated gas can be discharged quickly.

[0013] In the electronic component mounting jig of the present invention, it is preferable that the electronic component mounting surface intersects with the extrusion direction of the honeycomb shape. The electronic component mounting surface intersects with the extrusion direction of the honeycomb shape, so that a cavity can be formed that provides a path between the electronic component mounting surface and the atmosphere.

[0014] In the electronic component mounting jig of the present invention, the volume ratio of the framework portion to the electronic component mounting jig is preferably 25 to 50%. When the volume ratio of the aggregate portion in the electronic component mounting jig is 50% or less, the electronic component mounting jig can be easily processed, and when the volume ratio of the aggregate portion is 25% or more, the electronic component mounting jig can have sufficient strength to maintain the overall shape of the electronic component mounting jig. Effect of the Invention

[0015] According to the electronic component mounting jig of the present invention, since the jig itself is made of SiC, it has high heat resistance and oxidation resistance. In addition, since it is not made of solid SiC but is made of a cavity and an aggregate, it is easy to process because only the aggregate needs to be processed to obtain a desired shape, and it can be suitably used as an electronic component mounting jig. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1A is a perspective view that illustrates an example of an electronic component mounting jig of the present invention, and FIG. 1B is a cross-sectional view taken along line AA in FIG. 1A. [Diagram 2] FIG. 2 is a perspective view that typically illustrates an electronic component mounting step in which an electronic component is mounted on a ceramic substrate using an electronic component mounting jig. [Diagram 3] 3A, 3B, 3C, 3D, 3E, and 3F are cross-sectional views that typically show one example of a manufacturing process for an electronic component module using the electronic component mounting jig according to the first embodiment of the present invention. [Figure 4] 4A and 4B are process diagrams that diagrammatically show an example of a method for manufacturing the electronic component mounting jig shown in FIG. [Diagram 5] 5A and 5B are schematic diagrams showing modified examples of the electronic component mounting jig of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The electronic component mounting jig of the present invention is an electronic component mounting jig for mounting and heating electronic components, characterized in that the electronic component mounting jig is composed of a framework portion made of SiC and a hollow portion, and has an electronic component mounting surface on its surface.

[0018] SiC has high heat resistance and oxidation resistance, and has low reactivity with metals and semiconductor materials, making it suitable for use as a jig for mounting electronic components. On the other hand, SiC itself is a hard material, and is extremely difficult to process for use as a jig. In the present invention, the material is not solid but is made of an aggregate portion and a cavity portion, and since the aggregate portion is made of SiC, it can be easily processed as desired, making it suitable for use as a jig for mounting electronic components.

[0019] FIG. 1A is a perspective view that illustrates an example of an electronic component mounting jig of the present invention, and FIG. 1B is a cross-sectional view taken along line AA in FIG. 1A. FIG. 1A illustrates an electronic component mounting jig 1 according to a first embodiment of the present invention. An upper surface 11 of the electronic component mounting jig 1 is provided with six recesses 12 for mounting electronic components. The electronic component mounting jig 1 is composed of a framework portion 20 and a hollow portion 30, and the framework portion 20 is made of SiC.

[0020] The aggregate portion 20 has a honeycomb shape, and between the SiC ceramic walls 21 that constitute the aggregate portion 20, cavities 30 extend in the thickness direction of the electronic component mounting jig 1 (the direction of the arrow T in FIGS. 1A and 1B). The extending direction of the hollow portion 30 corresponds to the extrusion direction in which the honeycomb shape is formed by extrusion molding when the honeycomb shape is obtained. Since the aggregate portion has a honeycomb shape, it has high strength and has low resistance to gas passage, so that generated gas can be discharged quickly. Moreover, it is preferable that cavity 30 is connected to the outer surface of electronic component mounting jig 1 . Since the cavity is connected to the outer surface, gas, flux, brazing material vapor, etc. generated by the reaction between the electronic component and SiC are not retained in the gap between the electronic component mounting jig and the electronic component, and are quickly diffused to the outside. Furthermore, the cavity 30 is preferably a through hole. By having the cavity be a through hole, gas, flux, brazing material vapor, etc. generated by the reaction between the electronic component and SiC can be diffused to the outside more quickly.

[0021] An upper surface 11 of the electronic component mounting jig 1 is an electronic component mounting surface. The electronic component mounting surface is cut out so as to be perpendicular to the extrusion direction. When the electronic component mounting surface is perpendicular to the extrusion direction of the honeycomb shape, the cavity forms a path between the electronic component mounting surface and the atmosphere. The aggregate portion 20 is preferably a porous body. When the aggregate portion is a porous body, the aggregate portion has open pores that allow gas to pass through the aggregate portion. When the aggregate portion is porous, chipping is less likely to occur during processing, and an electronic component mounting jig with high dimensional accuracy can be obtained.

[0022] When the aggregate portion 20 is a porous body, the porosity of the aggregate portion is preferably 35 to 65%. When the porosity of the aggregate portion is 35% or more, it can be easily processed. When the porosity of the aggregate portion is 65% or less, sufficient strength for maintaining the overall shape can be obtained. When the aggregate portion is porous, the porosity can be measured by mercury intrusion porosimetry. The porosity can be measured by measuring the pore volume and pore size distribution using mercury intrusion porosimetry. The surface tension and contact angle of mercury are set to 485 mN / m and 130°, respectively, and the mercury is injected at a pressure ranging from atmospheric pressure to 200 MPa.

[0023] The depth of the recess 12 provided on the electronic component mounting surface is adjusted according to the thickness of the electronic components to be mounted, so that when the electronic components are mounted, the upper surfaces of multiple electronic components are aligned on the same plane.

[0024] The volume ratio of the framework portion shown in the electronic component mounting jig is preferably 25 to 50%. When the volume ratio of the aggregate portion in the electronic component mounting jig is 50% or less, the electronic component mounting jig can be easily processed, and when the volume ratio of the aggregate portion is 25% or more, the electronic component mounting jig can have sufficient strength to maintain the overall shape of the electronic component mounting jig. When calculating the volume ratio of the aggregate part, if the aggregate part is a porous body, the volume of the aggregate part is the volume including the pores in the porous body. The volume of the aggregate part shown in the total volume of the aggregate part and the hollow part (i.e. the total volume of the electronic component mounting jig) expressed as a percentage is the volume ratio of the aggregate part. The volume ratio of the aggregate portion can be calculated from the area ratio in a cross section that reflects the overall volume ratio. In the case of a honeycomb-shaped aggregate portion, this corresponds to the surface that intersects with the extrusion direction, and the ratio of the volume of the aggregate portion to the volume of the cavity portion is equal to the ratio of the cross-sectional area of ​​the aggregate portion to the cross-sectional area of ​​the cavity portion. In the case of a foam, the area ratio may be calculated in any cross section other than the surface.

[0025] FIG. 2 is a perspective view that typically illustrates an electronic component mounting step in which an electronic component is mounted on a ceramic substrate using an electronic component mounting jig. An electronic component 40 is placed in the recess 12 of the electronic component mounting jig 1 , a brazing material 50 is applied onto the electronic component 40 , and a ceramic substrate 60 is placed on the brazing material 50 . The electronic component 40, the brazing material 50, and the ceramic substrate 60 are stacked on the electronic component mounting jig 1, which is then placed in a heating oven and heated until the brazing material 50 melts. As the brazing material 50 melts, the ceramic substrate 60 and the electronic component 40 are bonded together. 2, an electronic component mounted substrate is obtained in which six electronic components 40 are mounted on a ceramic substrate 60. A wiring pattern is provided on the ceramic substrate 60 as appropriate, and current and signals are supplied from the outside to the electronic components via the wiring pattern. The electronic component is not particularly limited, but an IGBT element or the like can be used.

[0026] 3A, 3B, 3C, 3D, 3E, and 3F are cross-sectional views that typically show one example of a manufacturing process for an electronic component module using the electronic component mounting jig according to the first embodiment of the present invention. 3A shows the electronic component mounting process, FIG. 3B shows the heat sink mounting process, FIG. 3C shows the wire bonding process, FIG. 3D shows the bus bar and pin header mounting process, FIG. 3E shows the packaging process, and FIG. 3F shows the insulating resin filling process.

[0027] The diagram shown in Fig. 2 is a diagram of the electronic component mounting process shown in Fig. 3A, and the diagram shown in the upper part of Fig. 3A can also be considered as a cross-sectional view taken along line BB in Fig. 2. The lower part of Fig. 3A shows electronic component mounting board 70 in which electronic components 40 are mounted on ceramic substrate 60. Note that electronic component mounting board 70 is shown upside down in the upper and lower diagrams of Fig. 3A.

[0028] As shown in FIG. 3B, a heat sink 80 is attached to the surface of the ceramic substrate 60 opposite to the surface on which the electronic components 40 are mounted. As shown in FIG. 3C, wire bonding is performed on the surface of electronic component 40, and electrodes of electronic component 40 are led out by wires 90. 3D , the wires 90 are connected to a wiring pattern 100 provided in advance on the ceramic substrate 60, and a bus bar or pin header 110 is attached to a predetermined position of the wiring pattern 100. In this way, current and signals are supplied to the electronic component 40 from the outside via the bus bar or pin header 110 and the wiring pattern 100.

[0029] As shown in Fig. 3E, the device is molded in a resin package 120 so that the bus bar or pin header 110 is exposed to the outside. Furthermore, as shown in Fig. 3F, insulating resin 130 is filled inside the resin package. Through the above steps, the electronic component module 140 is manufactured.

[0030] 4A and 4B are process diagrams that diagrammatically show an example of a method for manufacturing the electronic component mounting jig shown in FIG. As shown in FIG. 4A, an upper part 210 and a lower part 220 are provided. Both the upper part 210 and the lower part 220 have a honeycomb shape, and the upper part 210 has an opening 215 for forming a recess. The upper component is cut out to provide an opening using a diamond tool, laser cutting, water guide laser, etc. Although the material constituting the electronic component mounting jig of the present invention is SiC, it has excellent workability, so that the opening can be easily provided. The top surface of the lower component is the surface on which electronic components are mounted when the lower component is combined with the upper component. It is preferable that the top surface of the lower component is polished to obtain a highly accurate electronic component mounting surface. The upper and lower components can be integrated by inserting positioning pins or bonding with molten silicon, and by dividing and processing the components, an electronic component mounting jig 1 as shown in FIG. 4B can be obtained without using small blades.

[0031] The electronic component mounting jig of the present invention is not limited to the electronic component mounting jig according to the first embodiment described above, and also includes the following modified examples. 5A and 5B are schematic diagrams showing modified examples of the electronic component mounting jig of the present invention. FIG. 5A is a schematic diagram of an electronic component mounting jig in the form of a foam, and FIG. 5B is a schematic diagram of an electronic component mounting jig in the form in which one side of a cavity is sealed.

[0032] Electronic component mounting jig 2 shown in FIG. 5A is obtained by foaming a SiC precursor in a container made of an organic material such as paper, and firing the same together with the container. In electronic component mounting jig 2 in the form of foam, framework portion 22 constituting the framework of the foam corresponds to the framework portion, and cavity 31 of the foam corresponds to the hollow portion.

[0033] The electronic component mounting jig 3 shown in Fig. 5B can be obtained by sealing one side of a honeycomb-shaped cavity 30 with a sealant 32. Although not shown in the drawing, a similar shape can also be obtained by molding using a mold.

[0034] Both electronic component mounting jigs 2 and 3 have hollow portions, so they can be easily machined to obtain the desired shape. In addition, in electronic component mounting jig 3, one side of the honeycomb-shaped hollow portion is sealed with a sealant, and a porous body can be obtained by adding an organic pore-forming material to the SiC raw material by extrusion molding or molding and sintering the material, thereby obtaining an electronic component mounting jig with excellent processability. [Explanation of symbols]

[0035] 1, 2, 3 Electronic component mounting fixture 11 Top surface (electronic component mounting surface) 12 Recess 20 Aggregate Department 21 Wall 22 Aggregate Department 30 Cavity 31 Cavity 32 Encapsulating materials 40 Electronic Components 50 Brazing material 60 Ceramic Substrate 70 Electronic component mounting board 80 Heatsink 90 Wire 100 Wiring Pattern 110 Busbar or pin header 120 Resin Package 130 Insulating resin 140 Electronic Component Module 210 Upper part 215 Aperture 220 Lower parts

Claims

1. An electronic component mounting jig for mounting and heating an electronic component, The electronic component mounting jig is composed of a framework portion made of a sintered body of SiC and a hollow portion connected to an outer surface, and has an electronic component mounting surface on a surface thereof; The aggregate portion is a porous body having a porosity of 35 to 65%, The electronic component mounting jig is composed of an upper member and a lower member each having an opening, The electronic component mounting jig is characterized in that the electronic component mounting surface formed by the upper surface of the lower member is polished.

2. 2. The electronic component mounting jig according to claim 1, wherein the framework portion has a honeycomb shape.

3. The electronic component mounting jig according to claim 2 , wherein the electronic component mounting surface intersects with an extrusion direction of the honeycomb shape.

4. 4. The electronic component mounting jig according to claim 1, wherein a volume ratio of the framework portion to the electronic component mounting jig is 25 to 50%.

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