JP2008135532A - Heat dissipation member, electronic component storage package and electronic device using the same - Google Patents

Abstract

A heat dissipating member having excellent heat dissipating performance that maintains good heat dissipating property even after long-term use, and an electronic component storage package and electronic device using the heat dissipating member are provided.
A heat radiating member A of the present invention has a thermal conductivity larger than one metal plate 2a, the other metal plate 2b, and these metal plates, and is interposed between the one metal plate 2a and the other metal plate 2b. , And inorganic particles 1 joined through an active metal brazing material 4 so as to be partially embedded in one metal plate 2a and the other metal plate 2b.
[Selection] Figure 1

Description

  The present invention relates to a heat radiating member that can efficiently dissipate heat generated by a high-power electronic component during operation to the outside, an electronic component housing package and an electronic device that use this heat radiating member and have good heat dissipation.

  An example of a conventional heat radiating member is shown in the cross-sectional view of FIG. As a conventional heat dissipating member, there is a heat sink (hereinafter referred to as a heat dissipating member) composed of diamond particles 101 having an average particle diameter of 50 μm or more and 800 μm or less and a metal 102 mainly composed of one or more of silver, copper, aluminum, gold or the like ( For example, see Patent Document 1).

  This heat dissipating member is obtained by putting diamond particles 101 in a frame serving as a jig for a predetermined heat dissipating member, spreading diamond particles 101 by adding shaking, and then pouring powder or paste-like metal 102 into the heat dissipating member frame. Then, a composite material is formed by combining the diamond particles 101 and the metal 102 in a state where the diamond particles 101 are arranged in a single layer. Then, after one layer is completed, this operation is repeated to obtain a laminated body having a predetermined thickness. Thereafter, the metal powder is melted by heating in vacuum, or a paste-like metal is sintered to obtain a heat radiating member in which the diamond particles 101 and the metal 102 are combined.

In this heat radiating member, in order to strengthen the adhesion between the diamond particles 101 and the metal 102, a small amount of a metal of the 4a to 7a group of the periodic table such as titanium is added, or it is preliminarily adhered to the diamond. It was.
Japanese Patent Laid-Open No. 9-312362

  However, when the metal powder between the diamond particles 101 is melted or a paste-like metal is sintered to form the metal 102, voids (voids) may occur in the metal 102. If this void is generated on the heat conduction path to the diamond particles, the heat conduction between the diamond particles is hindered.

  Accordingly, the present invention has been completed in view of the above-described conventional problems, and the object thereof is to provide a heat dissipating member excellent in heat dissipating performance in which heat dissipating performance is maintained well even in long-term use, and an electronic component using the same. It is to provide a storage package and an electronic device.

  The heat dissipating member of the present invention has one metal plate, the other metal plate opposed to the surface of the one metal plate, and a thermal conductivity larger than the thermal conductivity of the one metal plate and the other metal plate, and Inorganic particles interposed between the one metal plate and the other metal plate and joined via an active metal brazing material so as to be partially embedded in the one metal plate and the other metal plate. It is characterized by that.

  In the heat dissipating member of the present invention, the one metal plate and the other metal plate are made of silver, copper or aluminum.

  The heat dissipating member of the present invention preferably has the above structure, wherein the inorganic particles include at least one of diamond particles and cubic boron nitride particles.

  The heat radiating member of the present invention preferably has the above-described configuration, wherein at least one of the one metal plate and the other metal plate is chamfered between a surface and a side surface.

  The heat dissipating member of the present invention preferably has the above-described configuration, wherein the brazing material has a thickness of 5 μm or more and 25 μm or less.

  In the above configuration, the heat dissipating member of the present invention is preferably characterized in that a conductor is disposed between the inorganic particles so as to connect the one metal plate and the other metal plate.

  The heat dissipating member of the present invention preferably has the above-described configuration, and the heat dissipating member of the present invention is laminated in a plurality of layers.

  An electronic component storage package according to the present invention includes the heat dissipation member according to the present invention, and a terminal having a wiring conductor and attached to a surface outer peripheral portion of the heat dissipation member.

  The electronic component storage package of the present invention is characterized in that, in the electronic component storage package of the present invention, a fixing member is attached to a side surface of the heat radiating member.

  An electronic device according to the present invention includes the electronic component storage package according to the present invention, an electronic component that is installed at the center of the surface of the heat dissipation member to which the terminal is attached, and is connected to the wiring conductor. A sealing resin or a lid provided so as to cover is provided.

  The heat dissipating member of the present invention has one metal plate, the other metal plate opposed to the surface of the one metal plate, and a thermal conductivity larger than the thermal conductivity of the one metal plate and the other metal plate, and Inorganic particles interposed between the one metal plate and the other metal plate and joined via an active metal brazing material so as to be partially embedded in the one metal plate and the other metal plate. Therefore, the heat generated when the electronic component installed on the surface of the heat dissipation member operates is well transmitted from one metal plate to the other metal plate through inorganic particles having high thermal conductivity, It can be cooled efficiently. Furthermore, a metal plate is disposed in a portion that becomes a main heat conduction path, so that no gap is generated on the heat conduction path.

  In the heat dissipating member of the present invention, the one metal plate and the other metal plate may be made of silver, copper or aluminum, and the heat conductivity of these metals is large. The heat transmitted from the inorganic particles can be well transmitted to the outside.

  In the heat dissipation member of the present invention, the inorganic particles only need to contain at least one of diamond particles and cubic boron nitride particles, and these inorganic particles have very high thermal conductivity. The heat dissipating property of the heat dissipating member is improved.

  In the heat dissipation member of the present invention, at least one of the one metal plate and the other metal plate is preferably chamfered between the surface and the side surface, and when the metal plate is electroplated, the metal plate has a uniform thickness. A plating film can be formed.

  Further, in the heat dissipating member of the present invention, it is preferable that the brazing material has a thickness of 5 μm or more and 25 μm or less, so that the inorganic particles and one metal plate or the other metal plate can be satisfactorily bonded and the heat transfer performance can be increased. There is no loss.

  In the heat dissipation member of the present invention, a conductor may be disposed between the inorganic particles so as to connect the one metal plate and the other metal plate, and the electric resistance between the one metal plate and the other metal plate. Therefore, the heat radiating member can function as a ground for the electronic component.

  Further, the heat radiating member of the present invention may be formed by laminating a plurality of layers of the heat radiating member of the present invention, and the inorganic particles aligned in the direction orthogonal to the laminating direction can be stacked in an orderly manner, so that they are uniformly formed after lamination. It becomes a heat radiating member having a good thermal conductivity.

  In addition, the electronic component storage package of the present invention includes the heat dissipating member of the present invention, a wiring member, and a terminal attached to the outer peripheral portion of the surface of the heat dissipating member. It can be suitably used as a package that accommodates many electronic components.

  Further, the electronic component storage package of the present invention, in the electronic component storage package of the present invention, the fixing member is preferably attached to the side surface of the heat dissipation member, for example, when screwed to the external substrate, The fixing member portion can be used for screwing. Thereby, it is possible to prevent a mechanical force for fixing the electronic component storage package from being directly applied to the heat radiating member.

  An electronic device according to the present invention includes the electronic component storage package according to the present invention, an electronic component that is installed in the center of the surface of the heat dissipation member to which the terminal is attached, and is connected to the wiring conductor. Since the sealing resin or the lid provided so as to cover is provided, an electronic device that can suppress the temperature rise of the electronic component and operate the electronic component very well is obtained.

  The heat radiating member of the present invention, the electronic component storage package using the heat radiating member, and the electronic device will be described in detail below. 1 (a), 1 (b), and 1 (c) are cross-sectional views showing an example of an embodiment of a heat radiating member of the present invention. FIG. 2 (a), FIG. 2 (b), and FIG. (C) is sectional drawing which shows the other example of embodiment of the thermal radiation member of this invention. Moreover, Fig.3 (a) and FIG.3 (b) are the principal part expanded sectional views of the thermal radiation member of this invention. FIG. 4 is an enlarged sectional view of an essential part showing an example of the embodiment of the end of the heat radiating member of the present invention. 5 is a cross-sectional view showing an example of an electronic component storage package using the heat dissipation member shown in FIG. 1B, and FIG. 6 shows an example of an electronic apparatus using the electronic component storage package shown in FIG. It is sectional drawing. FIG. 7 is a perspective view showing an example in which an electronic device using another example of the embodiment of the electronic component storage package of the present invention (a state in which the electronic component and the lid are removed) is mounted on an external substrate. 8 (a), 8 (b), and 8 (c) are main part enlarged sectional views showing a section XX 'of FIG. 7 as each embodiment in the electronic component storage package of FIG. is there.

  In these drawings, 1 is inorganic particles, 2a is one metal plate (hereinafter also referred to as an upper metal plate), and 2b is the other metal plate arranged so that the upper surface faces the lower surface of the one metal plate. (Hereinafter also referred to as a lower metal plate) 3 is a conductor arranged to connect one metal plate 2a and the other metal plate 2b between the inorganic particles 1, and 4 is one metal plate 2a or the other metal plate 2b. And an active metal for joining the inorganic particles 1 partially embedded in the one metal plate 2a and the other metal plate 2b to the one metal plate 2a or the other metal plate 2b. It is included brazing material. The inorganic particles 1, the one metal plate 2a, the other metal plate 2b, and the brazing material 4 constitute the heat radiating member A of the present invention.

  Since the brazing material 4 is thin, the brazing material 4 is not shown in FIGS. 1 (a), 1 (b), 2 (a), and 2 (b). Further, the surface means a wide surface of the surfaces of the upper metal plate 2a or the lower metal plate 2b, and the surface drawn on the upper side in the figure is the upper surface and the surface drawn on the lower side, respectively. Called the lower surface.

  A1 is a mounting portion where the electronic component C is mounted and installed at the center of the surface where the terminal B of the heat dissipation member A is attached, and B is a terminal having a wiring conductor B1 for signal input / output. The member A and the terminal B constitute an electronic component storage package for storing the electronic component C in the mounting portion A1. A2 is a lower surface of the lower metal plate 2b of the heat dissipation member A, and the electronic component storage package is mounted on the external substrate or the like when the electronic component storage package is mounted on the external substrate or the like. A mounting surface that comes into contact with the surface of the external substrate, etc., C is an electronic component that is installed on the mounting portion A1 of the heat dissipation member A, and an electrode is connected to the wiring conductor B1, and D is a lid that is joined to the upper surface of the terminal B Yes, after mounting the electronic component C on the mounting part A1 of the electronic component storage package described above, the wiring conductor B1 and the electronic component C are electrically connected by an electrical connecting member such as a bonding wire, and the lid D is used for the electronic component. The electronic device is configured by sealing so as to cover C.

  The electronic device is fixed with the mounting surface A2 in close contact with an external substrate such as an external electric circuit substrate or a heat sink. As a result, the electronic device according to the present invention causes heat generated during the operation of the electronic component C to be transferred to the external substrate through the heat radiating member A, and suppresses the temperature rise of the electronic component C to ensure the operation reliability of the electronic component C. The property can be improved.

  The heat dissipating member A of the present invention includes an upper metal plate 2a and an upper metal plate 2a, as shown in FIG. 1 (a) and an enlarged cross-sectional view of a main portion of the heat dissipating member A according to the present invention. From the thermal conductivity of the lower metal plate 2b which is disposed opposite to the surface of the upper metal plate 2a and whose lower surface is the mounting surface A2 mounted on the external substrate, and the upper metal plate 2a and the lower metal plate 2b The Vickers hardness is higher than that of the upper metal plate 2a and the lower metal plate 2b, and the upper metal plate 2a and the lower metal are interposed between the upper metal plate 2a and the lower metal plate 2b. Electrons installed on the surface of the heat radiating member A are provided with the inorganic particles 1 joined via the brazing material 4 so that a part of the upper part 1a and the lower part 1b is embedded in the plate 2b. The heat generated when the component C is operated is from the upper metal plate 2a to the lower metal plate. b transmitted better via the large inorganic particles 1 of thermal conductivity. The electronic component C can be efficiently cooled by dissipating heat to an external board such as an external electric circuit board or a heat sink.

The inorganic particles 1 are made of a material having good thermal conductivity, and are, for example, non-metallic single crystal particles such as artificial diamond or cubic boron nitride, aluminum nitride (AlN), silicon nitride (Si ₃ N ₄ ), or carbonized. It consists of non-metallic particles with good thermal conductivity such as silicon (SiC). Alternatively, metal particles having good thermal conductivity such as silver and copper may be used.

  For example, the inorganic particles 1 are made of a material having higher thermal conductivity and Vickers hardness than the upper metal plate 2a and the lower metal plate 2b, and include at least one of insulating or conductive artificial diamond particles and cubic boron nitride particles. Contains. That is, for the inorganic particles 1, only artificial diamond particles, only cubic boron nitride particles, a mixture of these particles, or a mixture mainly composed of these particles is used. Among these particles, an artificial diamond having excellent physical properties is more preferable from the viewpoint of thermal conductivity and hardness, and considering that the metal film 4 can be easily formed by plating, boron is one of the artificial diamonds. A conductive material doped with (B), nitrogen (N) or the like is preferable. The particle diameter of the inorganic particles 1 is adjusted to a predetermined range by passing through a mesh having mesh sizes of 650 μm and 750 μm, for example.

  One or more inorganic particles 1 are used. When considering the maximum manufacturable diameter of the artificial diamond or cubic boron nitride particles as the inorganic particles 1 and the heat generation and size of the electronic component C, these inorganic particles are actually in the plane direction of the mounting portion A1. It is better to arrange a plurality of 1, and heat transfer characteristics can be further improved by increasing the heat radiation area. When a plurality of inorganic particles 1 are used, the inorganic particles 1 can be densely aligned on the lower metal plate 2b using an aligner or the like, and a plurality of inorganic particles 1 are arranged in the plane direction of the mounting portion A1. The arranged heat dissipating member A can be easily manufactured.

  The alignment by the aligner is performed by placing the inorganic particles 1 on the lower metal plate 2a and then vibrating the lower metal plate 2a. Artificial diamond particles and cubic boron nitride particles are crystal bodies having an irregular polyhedron, and by aligning in this way, one plane of the crystal body becomes substantially parallel to the surface of the lower metal plate 2b. Aligned. A part of the inorganic particles 1 is embedded in the upper metal plate 2a and the lower metal plate 2b, and the upper metal plate 2a, the lower metal plate 2b, and the inorganic particles 1 come into contact with each other on the surface.

  In this way, by arranging a plurality of small inorganic particles 1 with respect to the surface direction of the mounting portion A1, when mounting an electronic component having a very high exothermic property, or when mounting a large electronic component, The heat dissipating area can be easily increased, and the heat dissipating member A having good heat conduction characteristics can be obtained.

  Further, the brazing material 4 at the site where the inorganic particles 1 and the upper metal plate 2a are joined and at the site where the inorganic particles 1 and the lower metal plate 2b are joined has good thermal conductivity and an active metal is added. Use things. The brazing material 4 containing the active metal is, for example, any one of active metals such as silver (Ag) -copper (Cu) brazing, titanium (Ti), zirconium (Zr), niobium (Nb), hafnium (Hf). Is added in a small amount (1 to 20% by mass), and the bondability with the inorganic particles 1 becomes very strong. For example, when the inorganic particles 1 are artificial diamond, a carbide with an active metal is generated around the artificial diamond, and Ag—Cu wax can be firmly joined around the carbide. When the inorganic particles 1 are cubic boron nitride, a nitride with an active metal is generated around the cubic boron nitride, and Ag—Cu solder can be firmly joined around the nitride.

  Moreover, since the brazing material 4 is a relatively soft metal, the brazing material 4 has a buffering effect against external impacts on the inorganic particles 1. In addition, since the electrical conductivity is good, if the surface of the inorganic particles 1 is covered with the brazing material 4, the function of electrically connecting the upper metal plate 2a and the lower metal plate 2b can be achieved. it can. The brazing material 4 may also be used as the conductor 3 that fills the space between the inorganic particles 1.

  The thickness of the brazing material 4 after bonding is preferably 5 μm or more and 25 μm or less. When the thickness of the brazing material 4 (the total thickness of the brazing material 4 and the carbide or nitride) is less than 5 μm, the thermal stress buffering effect by the brazing material 4 is not sufficient, so , Cracks are likely to occur in hard carbides and nitrides. And with the time-dependent change, the upper metal plate 2a or the lower metal plate 2b and the inorganic particles 1 may be peeled off, making it difficult to transfer the heat generated by the electronic component C to the external substrate. On the other hand, when the thickness exceeds 25 μm, the thermal conductivity of the brazing material 4 is as low as about 300 W / mK as compared with the inorganic particles 1, so the heat between the upper metal plate 2 a or the lower metal plate 2 b and the inorganic particles 1 is low. It may become a blocking medium. Therefore, the thickness of the brazing material 4 is preferably 5 μm or more and 25 μm or less.

  When this brazing material 4 is used as the conductor 3 as shown in FIGS. 1B, 2B, and 3B, there is a particular problem even if a certain amount of voids are present in the conductor 3. There is no. That is, since the heat path transmitted to the external substrate through the upper metal plate 2a, the inorganic particles 1, and the lower metal plate 2b is dominant, voids in the brazing material 5 as the conductor 3 do not matter. The conductor 3 also functions as a holding member for the inorganic particles 1 against external impacts and the like. Furthermore, in the electronic component storage package or the electronic device, the inorganic particles 1 of the heat radiating member A are used when performing a helium leak test that is used when performing a hermeticity inspection of a portion (so-called cavity) that stores the electronic component. It also has a function of preventing the so-called pseudo leak that helium remaining in the space between them is detected.

  The conductor 3 only needs to be conductive. For example, a conductive resin such as silver epoxy in which silver particles are dispersed in an epoxy resin may be used. Further, when sufficient electrical continuity is obtained between the upper metal plate 2 a and the lower metal plate 2 b by the brazing material 4 deposited on the surface of the inorganic particles 1, a resin having no conductivity is used instead of the conductor 3. You may use for.

  The upper metal plate 2a and the lower metal plate 2b have a high thermal conductivity and are preferably a flexible metal, and copper, silver or aluminum is used. From the viewpoint of thermal conductivity, pure silver, pure copper, or pure aluminum having a purity of 99% or more is preferably used. The upper metal plate 2a and the lower metal plate 2b are formed by, for example, rolling a pure copper ingot to form a plate-like body having a thickness of about 0.1 mm, and further performing metal processing such as punching by press or wire electric discharge machining. Are processed into a copper plate or the like formed into a predetermined plan view shape.

  Since copper, silver, and aluminum metal are very soft, the inorganic particles 1 (the upper portion 1a and the lower portion 1b of the inorganic particles 1) are pressed into contact with the upper metal plate 2a and the lower metal plate 2b using a hot press or the like. It is easy to embed in the upper metal plate 2a and the lower metal plate 2b. Since the inorganic particles 1 are embedded in the upper metal plate 2a and the lower metal plate 2b, the thickness of the upper metal plate 2a and the lower metal plate 2b having lower thermal conductivity than the inorganic particles 1 is less than that of the inorganic particles 1. It becomes thin at the portion where is embedded, and heat is easily transferred to the inorganic particles 1.

  The upper metal plate 2a and the lower metal plate 2b have a function as a support substrate for fixing the inorganic particles 1 in addition to the function of mounting the electronic component C and placing the electronic component C on an external substrate. In addition, since the upper part 1a and the lower part 1b of the inorganic particles 1 are joined via the brazing material 4 with the upper part 1a and the lower part 1b being embedded in the upper metal plate 2a and the lower metal plate 2b, the upper metal plate 2a and the lower metal plate are joined. The bond strength of the particles to 2b is very high.

  Since the inorganic particles 1 are embedded in the upper metal plate 2a or the lower metal plate 2b, the lower surface of the upper metal plate 2a, the upper portion 1a of the inorganic particles 1, the upper surface of the lower metal plate 2b, and the inorganic particles 1 The contact area with the lower portion 1b is increased, and the heat transfer properties between the upper metal plate 2a and the lower metal plate 2b and the inorganic particles 1 are excellent. In addition, since the inorganic particles 1 are firmly joined to the upper metal plate 2a and the lower metal plate 2b via the brazing material 4, heat during processing of the brazing process or the operation of the electronic component C is repeatedly applied. However, the adhesion between the inorganic particles 1 and the upper metal plate 2a or the lower metal plate 2b becomes insufficient, and heat transfer is not impaired. The heat dissipating member A of the present invention efficiently externalizes heat from the electronic component C due to the heat conduction characteristics of the inorganic particles 1 having better heat conductivity than the heat conductivity of the upper metal plate 2a and the lower metal plate 2b. It can be transmitted to the substrate.

  In addition, the corner between the upper surface or lower surface of the upper metal plate 2a and the side surface (surface adjacent to the upper surface or lower surface) and the upper surface or lower surface and side surface (upper side of the lower metal plate 2b) It is preferable to chamfer at least one of the corners between the surface or the lower surface and the adjacent surface. That is, FIG. 4 shows at least part of the end portions 2ab of the upper metal plate 2a and the lower metal plate 2b, particularly the upper surface side end portion 2ab of the upper metal plate 2a and the lower surface side end portion 2ab of the lower metal plate 2b. As shown, it is preferable to chamfer the cross section into a curved surface or an inclined surface. As a result, when electroplating is performed on the surface of the heat dissipation member A, plating with a uniform thickness can be applied also to the end portions 2ab of the upper metal plate 2a and the lower metal plate 2b. In addition, it is possible to prevent an operator handling the heat radiating member A from being injured such as a cut by an acute edge of the upper metal plate 2a or the lower metal plate 2b.

  Such chamfering may be formed by the punching direction when performing punching, in addition to cutting or polishing the corner of the end 2ab of the upper metal plate 2a or the lower metal plate 2b.

  FIG. 9 is an explanatory view for schematically explaining the method of manufacturing the heat dissipation member A of the present invention. Hereinafter, the manufacturing method of the heat radiating member A of this invention is demonstrated using FIG.

  The heat radiating member A of the present invention is placed on the base plate in the order of the lower metal plate 2b, the thin plate of the brazing material 4, the inorganic particles 1, the thin plate of the brazing material 4, and the upper metal plate 2a. The upper metal plate 2a and the lower metal plate 2b can be manufactured by a hot uniaxial pressing method (hereinafter referred to as hot pressing) in which pressure is applied while adjusting the temperature so as not to melt. For example, a copper plate is used for the upper metal plate 2a and the lower metal plate 2b, and an active metal brazing material 4 in which 3% of titanium is added to a silver-copper brazing material such as BAg-8 is hot pressed.

  By adjusting the amount of the brazing material 4 to be small, as shown in FIG. 1 (a) or FIG. 3 (a), between the upper metal plate 2a and the lower metal plate 2b and the inorganic particles 1, and between the inorganic particles 1 Four layers of brazing material are formed so as to connect the upper metal plate 2a to the lower metal plate 2b from the side upper metal plate 2a to the lower metal plate 2b. Further, the amount of the brazing material 4 is increased as shown in FIG. 3 (b) showing an enlarged cross section around one inorganic particle 1 of the heat dissipating member A of the present invention shown in FIG. 1 (b) or FIG. 2 (b). Preparation or mixing so that the powder of the brazing material 4 is mixed between the inorganic particles 1, and the excess brazing material 4 is flown so as to fill the space between the inorganic particles 1 so as to be the conductor 3. Is done.

  Then, due to the pressure applied to the upper metal plate 2a and the lower metal plate 2b, the inorganic particles 1 pass through the thin film of the brazing material 4 so that the upper portion 1a is the upper metal plate 2a and the lower portion 1b is the lower metal. It joins so that it may be embedded in the board 2b. Since the four layers of the brazing material of the upper part 1a and the lower part 1b of the inorganic particles 1 are thinly formed by applying pressure, voids and the like are difficult to enter. Furthermore, since metal plates are used for the upper metal plate 2a and the lower metal plate 2b, voids and the like are less likely to enter the upper metal plate 2a and the lower metal plate 2b.

  In addition to the brazing material 4, a conductive resin such as silver epoxy as the conductor 3 may be separately injected into the space formed between the side surfaces of the inorganic particles 1 as shown in FIG. good. Further, when hot pressing is performed in a vacuum atmosphere, it is possible to avoid oxidation of the upper metal plate 2a, the lower metal plate 2b, the silver-copper brazing material as the brazing material 4, etc., and to improve the bondability and heat transfer characteristics. It can be maintained well.

  Further, the distance between the upper surface of the upper metal plate 2a and the brazing material 4 and the distance between the lower surface of the lower metal plate 2b and the brazing material 4 are smaller, that is, the upper metal plate 2a and the inorganic material just above the inorganic particles 1 are inorganic. As the thickness of the lower metal plate 2b immediately below the particle 1 is thinner, the heat generated by the electronic component C can be transmitted to the inorganic particle 1 more quickly, and the heat conduction characteristics of the inorganic particle 1 can be effectively utilized. The thicknesses of the upper metal plate 2a and the lower metal plate 2b by embedding the inorganic particles 1 are preferably set so that the minimum thickness is 15 μm by appropriately adjusting the pressing force in the hot press. When thinner than 15 μm, the brazing material 5 diffuses into the upper metal plate 2a or the lower metal plate 2b, so that a white stain appears on the surface of the upper metal plate 2a or the lower metal plate 2b. May cause problems.

  Further, by making the upper metal plate 2a and the lower metal plate 2b thick and performing hot pressing by adjusting the pressure and temperature conditions, as shown in FIG. It is also possible to obtain a heat dissipation member A in which most of the inorganic particles 1 are embedded in the upper metal plate 2a and the lower metal plate 2b in 1b.

  When the electronic component C is joined to the mounting portion A1 with solder such as gold-tin alloy or gold-germanium alloy, at least the upper surface of the upper metal plate 2a is preferably plated with nickel and gold.

  Then, artificial diamond particles having a particle size of 650 μm to 750 μm are used as the inorganic particles 1, and the upper metal plate 2 a made of copper having a thickness of 0.1 mm and a lower surface are disposed on the surface thereof through a brazing material 4 (BAg-8) having a thickness of 20 μm. The heat radiating member A embedded in the portion where the inorganic particles 1 are embedded is embedded so that the thickness of the upper metal plate 2a and the lower metal plate 2b is 15 μm or more. For example, the heat radiating member A of the present invention having a thermal conductivity of 500 W / mK or more can be obtained. That is, it can be set as the heat radiating member A which has a heat conductivity larger than the heat conductivity of the upper metal plate 2a or the lower metal plate 2b.

  Furthermore, as shown in FIG. 2A, FIG. 2B, and FIG. 2C, a plurality of heat dissipation members A can be stacked in a direction perpendicular to the surface direction of the mounting portion A1. . In FIGS. 2A and 2B, an example in which two layers are stacked is shown, but a multilayer structure can also be used.

  A method of directly stacking a large number of inorganic particles 1 in the vertical direction is also conceivable in increasing the size, but it is difficult to arrange and stack them in an orderly manner because the inorganic particles 1 have an irregular shape. Moreover, even if it can be laminated | stacked, since the inorganic particles 1 are irregularly shaped, it is not easy to align the directions of the inorganic particles 1, and the inorganic particles 1 are in contact with each other in a very small area such as point contact. Therefore, it is not easy to improve the heat transfer between the particles. A method of making the inorganic particles 1 into a prismatic shape, a columnar shape, etc. with a well-shaped shape by polishing or the like and orderly stacking the inorganic particles 1 with each other is not practical because it takes a lot of time and cost for polishing and stacking operations. On the other hand, according to the method of stacking the heat radiation member A of the present invention, the inorganic particles 1 can be stacked in an orderly manner in the vertical direction.

  Lamination of the heat radiating members A may be performed, for example, by joining the lower metal plate 2b of the other heat radiating member A to the surface of the upper metal plate 2a of the one heat radiating member A by brazing or the like. Alternatively, the upper metal plate 2a of the one heat radiating member A and the lower metal plate 2b of the other heat radiating member A may be used as a single metal plate and hot-pressed to form a multilayer heat radiating member A. However, if one common metal plate is used, it is difficult to apply pressure between the inorganic particles 1 and the common metal plate depending on the positions of the inorganic particles 1 arranged above and below the common metal plate. It may be difficult to embed in the board.

  Further, as shown in FIG. 2C, a molybdenum (Mo) plate 6 having a thickness of about 20 μm is interposed between the upper metal plate 2a of the one heat radiating member A and the lower metal plate 2b of the other heat radiating member A. When brazed, the thermal expansion coefficient in the surface direction of the laminated heat radiating member A becomes smaller than that of copper, silver, aluminum, etc., and the heat radiating member A having good compatibility with the thermal expansion coefficient of the electronic component C It can be.

  Next, as shown in FIG. 5, the electronic component storage package of the present invention is attached to the upper surface having the heat dissipating member A of the present invention and the mounting portion A <b> 1 by brazing or the like. And a terminal B having a wiring conductor B1 for signal input / output to be connected. The thermal expansion coefficient of the heat radiating member A largely depends on the size and number of the inorganic particles 1 and the size and thickness of the upper metal plate 2a and the lower metal plate 2b. Since the thermal expansion coefficient of the inorganic particles 1 is smaller than that of the upper metal plate 2a and the lower metal plate 2b, the thermal expansion coefficients of the heat radiating member A and the terminal B can be substantially matched by using these in combination. is there. Therefore, the residual thermal stress after manufacturing the electronic component storage package is also reduced, and it is possible to mount the electronic component C such that a large thermal stress is applied to the electronic component storage package by the electronic component C that generates a large amount of heat. It becomes.

Further, the terminal B is alumina _(Al 2 _{O 3)} sintered material, aluminum nitride (AlN) sintered material, mullite _{(3Al 2 O 3 · 2SiO 2} ) sintered material, the surface of the ceramics such as glass ceramics A wiring conductor B1 composed of a metallized layer for signal input / output is formed on the outside, and lead terminals for electrical connection with an external electric circuit board (not shown) are provided on the outer surface of the electronic component storage package of the wiring conductor B1. Be joined. Then, the mounting portion A1 is attached to the upper surface of the heat radiating member A via solder, resin, brazing material, glass or the like.

If the terminal B is made of, for example, an Al ₂ O ₃ sintered material, it is suitable for a raw material powder such as Al ₂ O ₃ , silicon oxide (SiO ₂ ), magnesium oxide (MgO), calcium oxide (CaO), etc. A mixture of organic binders, solvents, plasticizers, dispersants, etc. is added to form a slurry, and from this, a ceramic green sheet (ceramic raw sheet) is formed by adopting a doctor blade method or a calender roll method. In addition, the ceramic green sheet is subjected to an appropriate punching process, and a conductive material obtained by mixing an appropriate organic binder and solvent with a metal material powder such as W, Mo, Mn, Cu, Ag, Ni, Au, and palladium (Pd). After a functional paste is applied to a green sheet in advance by a screen printing method or the like in a predetermined pattern of the wiring conductor B1, this paste is applied. The green sheet laminating a plurality, is produced by firing at a temperature of about 1600 ° C..

  Further, when a metal having excellent corrosion resistance such as Ni and Au and excellent bonding property of electrical connection means such as a bonding wire is deposited on the exposed surface of the wiring conductor B1 to a thickness of 1 to 20 μm by a plating method, The oxidative corrosion of the wiring conductor B1 can be effectively prevented and the bonding force of the electrical connection means to the wiring conductor B1 can be strengthened.

  Next, as shown in FIG. 6, the electronic component C is mounted on the mounting portion A1 of the electronic component storage package of the present invention via an adhesive such as solder, resin, brazing material, or glass. As the electronic component C, various electronic components C such as a semiconductor element, a piezoelectric vibrator, a chip capacitor, a transistor, and a light emitting element can be mounted. In particular, even when an electronic component C that generates a large amount of heat, such as a high-power field effect transistor (FET), is mounted on the mounting portion A1 of the heat dissipation member A, the heat generated from the electronic component C is efficiently generated. It can be diffused out of the electronic component storage package. Then, after mounting the electronic component C on the mounting portion A1 via an adhesive, the electrode of the electronic component C and the wiring conductor B1 of the terminal B are electrically connected by an electrical connection means such as a bonding wire, and further, by sealing resin The electronic device of the present invention is manufactured by so-called potting or by airtightly sealing the upper surface of the terminal B with the lid D.

  In addition, since the heat radiating member A of this invention is a composite_body | complex which joined the inorganic particle 1 like a diamond particle, and the metal plates 2a and 2b, it is preferable that a bending stress, a compressive stress, etc. are not added. Therefore, when the heat radiating member A is fixed to the external substrate with screws or the like, FIG. 7 and an enlarged sectional view of the end of the heat radiating member A along the cutting plane XX ′ are shown in FIG. 8 (a), FIG. 8 (b), FIG. As shown in (c), it is better to fix the fixing member 5 for screwing to the side surface of the heat radiating member A. Thus, by fixing the heat radiating member A so as to be in close contact with the external substrate with screws, the mounting surface A2 can be brought into close contact with the surface of the external substrate without using a bonding material or the like. The heat transfer between them can be improved. In FIGS. 8A, 8B, and 8C, the screw in the screw hole 5a and the external substrate are not shown.

  The fixing member 5 is made of a flexible material such as metal or resin. For example, if it is a metal, silver, copper, iron (Fe) -nickel alloy, iron-nickel-cobalt (Co) alloy, etc. may be used. Moreover, if it is resin, an epoxy resin or a silicone resin is mentioned. As shown in FIG. 8 (a), when the fixing member 5 is directly and closely joined to the upper metal plate 2a and the lower metal plate 2b, particularly an iron-nickel alloy or an iron-nickel-cobalt alloy is used. Thus, the thing approximated to the thermal expansion coefficient of the heat radiating member A is good. Further, as shown in FIG. 8 (c), it may be joined to the upper metal plate 2a and the lower metal plate 2b via the conductor 3, and in the same manner as in FIG. 8 (a), particularly an iron-nickel alloy. What approximated the thermal expansion coefficient of the heat radiating member A like an iron-nickel-cobalt alloy is good. Further, as shown in FIG. 8C, the end 2ab of the upper metal plate 2a (at least the upper end 2ab), the end 2ab of the lower metal plate 2b (at least the lower end 2ab), and It is better that at least one of the end portions 5b of the fixing member 5 on the heat radiating member A side has a chamfered surface that is curved or inclined (C cut surface), and the fixing member 5 and the upper and lower sides are chamfered. The metal plates 2 a and 2 b can be bonded very firmly by the meniscus of the bonding material 7. In addition, in FIG.8 (c), the thickness of the brazing material 7 is emphasized and drawn thickly.

  Thus, even when the amount of heat generated during operation of the electronic component C is very large, the electronic device C can be maintained at an appropriate operating temperature and can be operated normally and reliably.

  In addition, this invention is not limited to the example of the above embodiment, A various change is possible if it is the range which does not deviate from the summary of this invention. For example, instead of the discrete electronic component C, the ceramic circuit board may be mounted on the mounting portion A1 on the upper surface of the heat dissipation member A, and the electronic component C may be mounted on the circuit board.

  In the description of the above embodiment, the terms “upper, lower, left and right” are merely used to describe the positional relationship in the drawings, and do not mean the positional relationship in actual use.

(A), (b), (c) is sectional drawing which shows an example of embodiment of the thermal radiation member of this invention, respectively. (A), (b), (c) is sectional drawing which shows the other example of embodiment of the thermal radiation member of this invention, respectively. (A), (b) is the principal part expanded sectional view of FIG. 1 (a), (b), respectively. It is a principal part expanded sectional view which expands and shows the example of the edge part of the heat radiating member of this invention. It is sectional drawing which shows an example of embodiment of the electronic component storage package of this invention. It is sectional drawing which shows an example of embodiment of the electronic device of this invention. It is a perspective view which shows the example by which the electronic device using the other example of the electronic component storage package of this invention is mounted in an external substrate. (A), (b), (c) is principal part expanded sectional drawing which shows each example of the cross section X-X 'of the electronic component storage package of FIG. It is the schematic explaining the manufacturing method of the heat radiating member of this invention. It is sectional drawing which shows the example of the conventional heat radiating member.

Explanation of symbols

1: Inorganic particles 1a: Upper part (of inorganic particles 1) 1b: Lower part (of inorganic particles 1) 2a: One metal plate (upper metal plate)
2b: the other metal plate (lower metal plate)
2ab: end portion 3: conductor 4: brazing material 5: fixing member A: heat radiating member A1: mounting portion A2: mounting surface B: terminal B1: wiring conductor C: electronic component D: lid

Claims (10)

One metal plate, the other metal plate disposed opposite to the surface of the one metal plate, and having a thermal conductivity larger than that of the one metal plate and the other metal plate, and the one metal plate and the other metal plate Inorganic particles interposed between active metal brazing materials so as to be partially embedded in the one metal plate and the other metal plate. A heat dissipating member. 2. The heat radiating member according to claim 1, wherein the one metal plate and the other metal plate are made of silver, copper, or aluminum. The heat radiating member according to claim 1, wherein the inorganic particles include at least one of diamond particles and cubic boron nitride particles. The heat radiating member according to claim 1, wherein at least one of the one metal plate and the other metal plate is chamfered between a surface and a side surface. The heat radiating member according to claim 1, wherein the brazing material has a thickness of 5 μm to 25 μm. The heat radiating member according to any one of claims 1 to 5, wherein a conductor is disposed so as to connect the one metal plate and the other metal plate between the inorganic particles. A heat dissipating member comprising a plurality of heat dissipating members according to any one of claims 1 to 6. An electronic component storage package comprising: the heat dissipating member according to claim 1; and a terminal having a wiring conductor and attached to the outer peripheral portion of the surface of the heat dissipating member. . 9. The electronic component storage package according to claim 8, wherein a fixing member is attached to a side surface of the heat radiating member. The electronic component storage package according to claim 8 or 9, and an electronic component that is installed at the center of the surface of the heat dissipation member to which the terminal is attached and is connected to the wiring conductor, and covers the electronic component An electronic device comprising a sealing resin or a lid provided as described above.

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