JP2005277382A - Package for storing electronic component, and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a package for storing an electronic component which can emit well the heat generated by the electronic component to the outside or into the atmosphere and can firmly join the electronic component to a heat radiation member, and to provide an electronic device using the package. <P>SOLUTION: The electronic device comprises the heat radiation member 1 including a mounting portion 10 for mounting the electronic component 11, a rectangular frame 5, and a plurality of interconnection conductors 6. The heat radiation member 1 comprises a frame-like substrate 2 formed of a tungsten or molybdenum sintered material impregnated with copper, a through metal body 5 which is formed of copper or an alloy mainly formed of copper and is embedded in the central part of the substrate 2, and copper layers 4a and 4b so formed as to cover the top and bottom surfaces of the substrate 2 and through metal body 5. About the frame 5, bottom surfaces of first and second side walls having a pair of facing sides are located outside the through metal body 5, and bottom surfaces of third and fourth side walls having another pair of facing sides overlap the ends of the through metal body 5 when seen in top view. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic component storage package for storing an electronic component such as a semiconductor element, which has a heat dissipation structure with good heat dissipation characteristics, and an electronic device using the same.

  Conventionally, electronic component storage packages for storing electronic components such as semiconductor elements, piezoelectric vibrators, and light emitting elements are generally made of an electrically insulating material such as an aluminum oxide sintered body, a mullite sintered body, and a glass ceramic. A frame and a sintered body made of tungsten or molybdenum, which is used to dissipate the heat generated when the electronic component is mounted and in operation to the outside or the atmosphere, is impregnated with copper (tungsten or molybdenum and copper The heat sink is made of a copper-tungsten alloy or a copper-molybdenum alloy and a lid, and a frame is disposed so as to surround the electronic component mounting portion on the upper surface of the heat sink. In addition, from the inside to the outside of the recess formed by the frame and the heat dissipation member, tungsten, molybdenum Manganese, copper, a plurality of wiring conductors made of silver or the like is derived is applied to the frame.

  The electronic component is bonded and fixed to the mounting portion on the upper surface of the heat radiating member via a bonding material such as glass, resin, or brazing material, and each electrode of the electronic component is electrically connected to the wiring conductor via a bonding wire. After that, the lid body is joined to the frame body through a sealing material made of glass, resin, brazing material, etc., and the electronic component is accommodated in the container composed of the heat radiation member, the frame body, and the lid body. Thus, an electronic device as a product is obtained (for example, see Patent Document 1 below). In order to further improve the heat dissipation efficiency, this electronic device may be mounted on an external heat sink by screwing or the like.

  An electronic component storage package having a heat dissipation member made of such a copper-tungsten alloy or a copper-molybdenum alloy has a high heat conductivity of the heat dissipation member, and a thermal expansion coefficient of the heat dissipation member is a semiconductor as an electronic component. Electronic component storage package equipped with high heat-generating semiconductor elements such as power ICs and high-frequency transistors because the thermal expansion coefficient is close to that of silicon, gallium arsenide, which is the component material of the element, and ceramic materials used as the component material of the package It is attracting attention as.

  In recent years, a heat dissipation member having a thermal conductivity of 300 W / m · K or more has been demanded due to an increase in the amount of heat generated with the high integration of power ICs and high-frequency transistors. However, the heat conductivity of the heat radiating member made of the above-mentioned alloy material of tungsten and copper or the alloy material of molybdenum and copper is about 200 W / m · K, which is low for that requirement, so the heat dissipation characteristics are insufficient. There was a problem.

  On the other hand, it has been proposed to use a heat dissipation member formed by impregnating copper into a composite material in which tungsten or molybdenum and copper are formed in a matrix, that is, a sintered body made of tungsten or molybdenum.

  As an electronic device, as shown in FIG. 7, the first metal material 102 is formed by brazing and bonding second metal materials 104 a and 104 b having higher thermal conductivity than the first metal material 102 on both upper and lower surfaces. In addition, a through hole is formed in the first metal material 102 almost directly below the electronic component 111 mounted on the upper surface of the second metal material 104a. The through hole has a thermal conductivity higher than that of the first metal material 102. The metal heat sink 101 in which the high third metal material 103 is inserted, and the electronic component 111 is mounted on the upper surface of the metal heat sink 101, and is mounted on the upper surface of the metal heat sink 101 so as to surround the electronic component 111. An electronic device 114 including a frame body 105 and a lid body placed on the upper surface of the frame body 105 has been proposed (see, for example, Patent Document 2 below).

  The first metal material 102 of the electronic device 114 is made of molybdenum, tungsten, iron alloy or the like, the second metal materials 104a and 104b are made of copper or the like, and the third metal material 103 is copper, silver, aluminum or diamond. Etc.

With this configuration, it is possible to easily obtain the electronic device 114 having good heat dissipation without causing warpage of the metal radiator 101 or cracking of the frame 105 joined to the metal radiator 101. .
Japanese Patent Laid-Open No. 2002-124611 Japanese Patent No.2765621 Japanese Patent No. 3333682

  However, in an electronic component storage package using a heat dissipation member made of a composite material in which tungsten or molybdenum and copper are formed in a matrix, tungsten or molybdenum has a low thermal conductivity and a low thermal expansion coefficient, and copper Since both the conductivity and the coefficient of thermal expansion are high, the heat conductivity and the coefficient of thermal expansion of the heat radiating member both increase as the copper content increases. Therefore, if the copper content is increased in order to improve the thermal conductivity of the heat dissipation member, the difference in coefficient of thermal expansion between the electronic component and the heat dissipation member increases, and the electronic component can be firmly bonded to the heat dissipation member. There was a problem that it was impossible.

  The present invention has been devised in view of the above problems in the prior art, and the purpose thereof is to dissipate the heat generated by the electronic component well to the outside or the atmosphere, and the electronic component is used as a heat dissipation member. An object of the present invention is to provide an electronic component storage package that can be firmly bonded and an electronic device using the same.

  An electronic component storage package according to the present invention includes a flat plate-like heat radiating member having an electronic component mounting portion at the center of the upper surface, and a rectangular frame attached to the upper surface of the heat radiating member so as to surround the mounting portion. And a plurality of wiring conductors led to the outer surface from the inner surfaces of a pair of opposing side portions of the frame body, and the heat dissipation member is obtained by impregnating a sintered body made of tungsten or molybdenum with copper. A penetrating metal body made of copper or an alloy containing copper as a main component is embedded from the upper surface to the lower surface of the central portion of the frame-shaped substrate, and the copper layer covers the upper and lower surfaces of the substrate and the penetrating metal body, respectively. And the lower surface of the first and second side walls each having a pair of opposing side portions are positioned outside the penetrating metal body and the other pair of opposing sides. Each part The lower surface of the third and fourth side walls is characterized in that overlaps with an end portion of the through-metallic body in a plan view.

  In the electronic component storage package of the present invention, preferably, each cross-sectional area in the vertical cross section of the third and fourth side walls of the frame body is greater than each cross-sectional area in the vertical cross section of the first and second side walls. It is large.

  In the electronic component storing package according to the present invention, preferably, the copper layer is formed by bonding a copper plate via a brazing material made of an alloy mainly composed of silver.

  In the electronic component storage package of the present invention, it is preferable that the brazing material has an area ratio of 15% or less in the cross section parallel to the main surface of the base body.

  In the electronic component storage package according to the present invention, preferably, the heat radiating member has a side metal layer attached to an outer surface of the base.

  In the electronic component storage package of the present invention, it is preferable that the copper layer on the upper surface side has a thickness that is smaller at the portion located outside the frame than the remaining portion.

  In the electronic component housing package of the present invention, preferably, the frame body is joined to the heat radiating member via a metal frame member.

  In the electronic component storage package according to the present invention, preferably, the frame-shaped member has an outer peripheral end located outside the outer surface of the frame.

  The electronic device according to the present invention includes the electronic component storage package according to the present invention, the electronic component mounted on the mounting portion and having an electrode electrically connected to the wiring conductor, and the upper surface of the frame. A lid attached to cover the electronic component or a sealing resin filled to cover the electronic component is provided inside the frame.

  The electronic component storage package of the present invention has a flat plate-like heat radiating member having an electronic component mounting portion at the center of the upper surface, a quadrangular frame attached around the mounting portion on the upper surface of the heat radiating member, and A plurality of wiring conductors led out from the inner surface of a pair of opposite side portions of the frame body, and the heat dissipation member is a frame-shaped member formed by impregnating a sintered body made of tungsten or molybdenum with copper. A through metal body made of copper or an alloy containing copper as a main component is embedded from the upper surface to the lower surface of the central portion of the base body, and a copper layer is formed covering the upper and lower surfaces of the base body and the through metal body, respectively. The frame body has third and third lower surfaces of the first and second side walls each having a pair of opposing side portions, the outer surfaces of the first and second side walls being positioned outside the penetrating metal body, and each of the other pair of opposing side portions. 4 side wall underside Since it overlaps with the end of the penetrating metal body in a plan view, it has a larger volume under the mounting part of the electronic component than a heat radiating member made by impregnating copper with a conventional sintered body made of tungsten or molybdenum. Since the heat conduction part made of copper can be arranged, the heat generated in the electronic component can be transferred more in the direction perpendicular to the mounting surface of the electronic component. As a result, the heat generated in the electronic component can be transferred to the heat dissipation member. Can be dissipated very well in the atmosphere or to an external heat sink.

  Further, even if a through metal body made of copper or an alloy containing copper as a main component is thermally expanded, a frame-like base body formed by impregnating copper into a sintered body made of tungsten or molybdenum restrains the through metal body. The thermal expansion of the whole heat radiating member can be suppressed. Therefore, although the proportion of copper in the heat radiating member is large, the thermal expansion of the entire heat radiating member can be reduced, and the strong bonding between the electronic component and the heat radiating member can be maintained.

  Furthermore, the copper layers formed on the upper and lower sides of the heat radiating member can transfer more heat generated by the electronic components in the direction parallel to the heat radiating member, and are transmitted in both the direction perpendicular to the heat radiating member and the direction parallel to the heat radiating member. It can be heated and the heat dissipation of the electronic component can be greatly improved. As a result, the electronic component can be operated normally and stably over a long period of time.

  In addition, the frame body has third surfaces in which the lower surfaces of the first and second side walls each having a pair of opposing side portions are positioned outside the through metal body and have another pair of opposing side portions. Since the lower surface of the fourth side wall overlaps the end of the penetrating metal body in plan view, the boundary portion between the penetrating metal body and the base of the heat dissipation member that is relatively weak is covered with a part of the frame. Thus, the heat radiating member can be reinforced, and the heat radiating member can be effectively prevented from being warped or deformed.

  In the electronic component storage package according to the present invention, preferably, each cross-sectional area in the longitudinal section of the third and fourth side walls of the frame is larger than each cross-sectional area in the longitudinal section of the first and second side walls. Even if the stress due to the difference in thermal expansion between the through metal body and the base acts on the third and fourth side walls of the frame body that covers a part of the through metal body, the bending of the third and fourth side walls of the frame body By increasing the strength, it is possible to effectively prevent cracks and the like from occurring on the third and fourth side walls of the frame.

  In the electronic component storage package of the present invention, it is preferable that the copper layer is formed by bonding a copper plate via a brazing material made of an alloy containing silver as a main component. It is also possible to transmit it through a brazing material made of an alloy mainly composed of good silver, and heat can be dissipated more efficiently. Also, since the brazing material mainly composed of silver is easily plastically deformed, it tends to warp the heat radiating member due to the difference in thermal expansion coefficient between the heat radiating member and the frame when joining the heat radiating member and the frame. Even if stress occurs, the stress can be relaxed satisfactorily. Therefore, it is possible to prevent the heat radiating member from being warped, maintain the flatness of the upper surface of the heat radiating member, improve the adhesion to the electronic component, and maintain the flatness of the lower surface of the heat radiating member. In addition, the heat radiation member can be thermally conducted efficiently from the heat radiating member to the support substrate with good adhesion of the heat radiating member to the support substrate. As a result, the heat dissipation of the electronic component storage package can be increased by the good thermal conductivity of the heat dissipation member and the highly efficient heat conduction to the support substrate, and the electronic component can operate more normally and stably over a long period of time. It becomes possible to make it.

  In the electronic component storage package of the present invention, it is preferable that the brazing material has an area ratio of 15% or less in a cross section parallel to the main surface of the base body, so that the heat generated by the electronic component is transferred. It can be prevented from being blocked by voids in the brazing material, and the heat dissipation can be greatly improved. As a result, the electronic component can be operated normally and stably over a long period of time.

  In the electronic component storage package according to the present invention, preferably, the heat dissipating member has a side metal layer attached to the outer side surface of the base body, and therefore the copper layer on the upper surface side of the heat dissipating member out of the heat generated from the electronic component. What is transmitted from the central part to the outer peripheral part can be transmitted to the lower surface side of the heat radiating member on the side surface of the base body to dissipate heat, and the temperature difference between the central part and the outer peripheral part of the copper layer on the upper surface side can be increased. Therefore, heat conduction of the copper layer on the upper surface side can be performed efficiently. Then, by placing and fixing the heat dissipating member on the external electric circuit board or the like, the heat generated from the electronic component can be efficiently dissipated to the external electric circuit board or the like on the lower surface of the heat dissipating member. As a result, the electronic component can be efficiently cooled and can be operated normally and stably over a long period of time.

  In the electronic component storage package according to the present invention, preferably, the copper layer on the upper surface side has a thicker copper layer around the mounting portion of the heat dissipating member because the thickness of the copper layer is thinner than the remaining portion. Thus, while maintaining good thermal conductivity, the ratio of copper in the heat dissipation member can be reduced to reduce the difference in thermal expansion between the heat dissipation member and the frame. Therefore, when joining the heat dissipation member and the frame, the heat dissipation member is effectively prevented from warping due to the difference in thermal expansion coefficient between the heat dissipation member and the frame, and the flatness of the lower surface of the heat dissipation member is maintained. In addition, the adhesion to the support substrate can be improved, and heat can be efficiently conducted from the heat dissipation member to the support substrate. As a result, the heat dissipation of the electronic component storage package can be increased by the good heat conductivity of the heat dissipation member and the highly efficient heat conduction to the support substrate.

  In the electronic component storage package according to the present invention, preferably, the frame is joined to the heat radiating member via a metal frame-like member, so that stress due to a difference in thermal expansion between the heat radiating member and the frame is reduced. The frame-shaped member can absorb the crack and the frame can be effectively prevented from peeling off from the heat dissipation member, and the frame-shaped member from the copper layer on the upper surface side of the heat dissipation member. It is possible to conduct heat to the heat and dissipate heat from the outer surface of the frame-like member, thereby further enhancing the heat radiation effect.

  In the electronic component storage package of the present invention, preferably, since the outer peripheral end of the frame-shaped member is located outside the outer surface of the frame, the exposed area of the outer surface of the frame-shaped member can be increased. Heat can be conducted from the copper layer on the upper surface side of the heat dissipating member to the frame member, and heat can be radiated more efficiently from the outer surface of the frame member.

  An electronic device according to the present invention includes an electronic component storage package according to the present invention, an electronic component mounted on a mounting portion and having an electrode electrically connected to a wiring conductor, and an electronic component covered on an upper surface of a frame. And the sealing resin filled so as to cover the electronic component inside the lid or the frame attached to the electronic component, the electronic component having the characteristics of the electronic component storage package of the present invention It is possible to provide an electronic device capable of operating an electronic component stably over a long period of time with extremely good heat dissipation characteristics.

  Next, the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view showing an example of an embodiment of an electronic component storage package and an electronic device using the same according to the present invention, and FIG. 2 is an electronic component storage package of FIG. 1 and an electronic device using the same. It is sectional drawing (sectional drawing seen from the side surface) of the direction orthogonal to a cross section. 1 is a heat radiating member, 2 is a base of the heat radiating member 1, 3 is a through metal body, 4 is a copper layer (4a is a copper layer on the upper surface side of the heat radiating member 1, 4b is a copper layer on the lower surface side of the heat radiating member 1), 5 Is a frame body, and 6 is a wiring conductor led out from the inner surface of the opposite side portion of the frame body to the outer surface. The heat radiation member 1 and the frame 5 constitute an electronic component storage package 8 for storing the electronic component 11. Further, after mounting the electronic component 11 on the mounting portion 10 of the heat radiating member 1, a sealing resin is filled so as to cover the electronic component 11 in the concave portion 5 a made up of the heat radiating member 1 and the frame body 5. The electronic device 14 of the present invention is configured by enclosing or by attaching the lid 13 to the upper surface of the frame 5 so as to cover the recess 5a and enclosing the electronic component 11.

  The frame 5 is made of an aluminum oxide sintered body, a mullite sintered body, glass ceramics, and the like, and is joined and fixed to the upper surface of the heat radiating member 1 via a brazing material such as silver brazing. To be attached. It should be noted that a brazing metal layer (not shown) may be formed at the joint portion of the frame 5 with the heat radiating member 1 when the brazing material is joined and fixed. The frame 5 may be made of metal. In that case, in order to insulate the wiring conductor 6 from the metal constituting the frame 5, the periphery of the wiring conductor 6 is made of an insulator such as ceramics, resin, or glass. Cover it.

  Hereinafter, although the frame 5 is described as a rectangular frame shape, the frame body 5 is not necessarily a rectangular frame shape, and may be a required shape such as a polygonal shape, a circular shape, or an elliptical shape.

  In addition, the electronic component 11 is fixed to the heat dissipating member 1 on the mounting portion 10 at the center of the upper surface via a bonding material such as resin, glass, brazing material or the like. In the case where a brazing material is used as the bonding material, a brazing metal layer (not shown) may be formed at the bonding portion 10 of the heat dissipation member 1 with the electronic component 11. However, when sufficient brazing can be performed by the copper layer 4a bonded to the mounting portion 10 on the upper surface of the heat radiating member 1, a brazing metal layer is not particularly necessary.

  Hereinafter, although the heat radiating member 1 is described as a rectangular flat plate shape, it is not necessarily a square flat plate shape, and may be a required shape such as a polygonal shape, a circular shape, or an elliptical shape.

  If the frame 5 is made of, for example, an aluminum oxide sintered body, an appropriate organic binder, solvent, plasticizer, dispersant, etc. are added to the raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, calcium oxide. A ceramic green sheet (ceramic green sheet) is formed by mixing and adding to a mud-like shape, and then adopting a doctor blade method and a calender roll method. After that, the ceramic green sheet is appropriately punched. Conductive paste made by mixing an appropriate organic binder and solvent with powders of metal materials such as tungsten, molybdenum, manganese, copper, silver, nickel, palladium, gold, etc. After printing and applying to the pattern of 6, this green sheet Laminating several sheets, it is produced by firing at a temperature of about 1600 ° C..

  Further, the frame body 5 is formed with a wiring conductor 6 led out from the inner surface (around the mounting portion 10) of the recess 5 a formed by the heat radiating member 1 and the frame body 5 to the outer surface of the frame body 5. Each electrode of the electronic component 11 is electrically connected to one end inside the recess 5 a of the conductor 6 through a bonding wire 12. A lead terminal 7 for connection to an external electric circuit board is connected to the other outer end of the frame 5 of the wiring conductor 6.

  The wiring conductor 6 is made of a refractory metal such as tungsten or molybdenum, and a metal paste obtained by adding and mixing an appropriate organic binder, solvent or the like to a metal powder such as tungsten or molybdenum is preliminarily applied to the ceramic green sheet serving as the frame 5. By printing and applying in a predetermined pattern by a screen printing method or the like, the heat radiating member 1 and the frame body 5 are deposited from the inner surface of the recess 5 a to the outer surface of the frame body 5.

  Further, when the wiring conductor 6 is coated with a metal having excellent corrosion resistance such as nickel and gold on the exposed surface and excellent bonding property of the bonding wire 12 to a thickness of 1 to 20 μm by a plating method, the wiring conductor 6 is obtained. As a result, it is possible to effectively prevent the oxidative corrosion of the bonding wire 12 and to strengthen the connection of the bonding wire 12 to the wiring conductor 6. Therefore, it is desirable that the wiring conductor 6 is coated with a metal having excellent corrosion resistance, such as nickel and gold, and excellent bonding properties on the exposed surface to a thickness of 1 to 20 μm.

  The heat dissipating member 1 of the present invention is a penetrating metal body made of copper or an alloy containing copper as a main component from the upper surface to the lower surface of the center portion of a frame-like substrate 2 formed by impregnating a sintered body made of tungsten or molybdenum with copper. 3 is embedded, and copper layers 4a and 4b are formed so as to cover the base 2 and the upper and lower surfaces of the through metal body 3, respectively. Further, notches and holes that serve as screwing portions (not shown) for fixing screws to a support substrate (not shown) are provided at the end of the heat radiating member 1 located outside the frame body 5 in FIG. Or you may. The penetrating metal body 3 does not necessarily have a rectangular parallelepiped shape, and may have a required shape such as a polygonal column shape or a cylindrical shape.

  The heat radiating member 1 has a function of absorbing heat generated by the operation of the electronic component 11 and dissipating it into the atmosphere, or conducting it to an external heat radiating plate or a support substrate. Such a heat radiating member 1 is, for example, first pressure-molded with tungsten powder or molybdenum powder having an average particle size of 5 to 40 μm so that a through hole is formed in a portion to be the mounting portion 10 of the electronic component 11, By sintering this in an atmosphere of 1300 to 1600 ° C., a porous body having through holes formed in the mounting portion 10 of the electronic component 11 from the upper surface to the lower surface is prepared in advance. Then, the porous body is impregnated with 10 to 50% by mass of copper at a melting point of copper of 1084 ° C. or higher in a hydrogen atmosphere, so that the sintered body made of tungsten or molybdenum is impregnated with copper (with tungsten or molybdenum and A flat substrate 2 (made of a matrix with copper) is produced. A through metal body 3 made of copper is embedded in the through hole formed in the center of the base body 2 from the upper surface to the lower surface of the base body 2, and the copper layer 4a and the upper surface of the base body 2 and the through metal body 3 are covered. It is formed by forming a copper layer 4 b so as to cover the lower surface of the substrate 2 and the through metal body 3.

  Here, the base body 2 is formed by impregnating a sintered body made of tungsten or molybdenum with copper, so that the thermal conductivity is improved as compared with the case where it is made of tungsten alone or molybdenum alone, and the heat radiation characteristics of the heat radiating member 1 are further improved. It can be excellent.

  The method of embedding the through metal body 3 in the through hole of the base 2 and the method of forming the upper and lower copper layers 4 are, for example, a method of plating the base 2, and after printing and applying a metal paste containing copper powder. A method of firing, or simultaneously heating a sintered body made of tungsten or molybdenum and a predetermined amount of copper to melt the copper, impregnating the porous sintered body with copper by a capillary phenomenon, and passing through the metal body 3 and The method of forming the copper layer 4 is mentioned. Alternatively, after the through metal body 3 is embedded in the through hole of the base body 2, the upper and lower surfaces of the base body 2 may be joined by bonding metal plates to be the upper and lower copper layers 4.

  Preferably, as shown in FIG. 3, in the heat radiating member 1, the copper layer 4 is formed by bonding a copper plate via a brazing material 15 made of an alloy mainly composed of silver. Examples of the brazing material 15 made of an alloy containing silver as a main component include a brazing material containing 72% by mass of silver and 28% by mass of copper.

  With this configuration, the heat generated in the electronic component 11 can be transmitted through the brazing material 15 made of an alloy whose main component is silver having good thermal conductivity, and heat can be more efficiently dissipated. Further, since the brazing material mainly composed of silver is easily plastically deformed, the heat radiating member 1 is warped due to the difference in thermal expansion coefficient between the heat radiating member 1 and the frame 5 when the heat radiating member 1 and the frame 5 are joined. Even if the stress to be generated is generated, the stress can be relaxed satisfactorily. Therefore, it is possible to effectively prevent the heat radiating member 1 from being warped, maintain the flatness of the upper surface of the heat radiating member 1 and improve the adhesion with the electronic component 11, and the flatness of the lower surface of the heat radiating member 1. In addition, it is possible to maintain the adhesion of the heat radiating member 1 to the support substrate and to efficiently conduct heat from the heat radiating member 1 to the support substrate. As a result, the heat dissipation of the electronic component storage package can be increased by the good thermal conductivity of the heat radiating member 1 and the highly efficient heat conduction to the support substrate, and the electronic component 11 can be more normal and stable over a long period of time. Can be activated.

  In the configuration shown in FIG. 3, the brazing material 15 covering the upper and lower surfaces of the base 2 and the penetrating metal body 3 preferably has voids formed by voids in the brazing material 15 in a cross section parallel to the main surface of the base 2. The area ratio of the area to the area of the joint surface is 15% or less. Thereby, the movement of the heat generated by the electronic component 11 is sufficiently prevented from being blocked by the voids in the brazing material 15, and the heat dissipation performance of the heat dissipation member 1 can be sufficiently exhibited. As a result, the electronic component 11 can be operated normally and stably over a long period of time.

  When the area ratio of the gap in the cross section parallel to the main surface of the substrate 2 is larger than 15%, the heat transfer generated by the electronic component 11 is easily hindered by the voids in the brazing material 15 and the heat dissipation is reduced. It becomes easy.

  Such a brazing material 15 is, for example, vertically embedded through the brazing material 15 which is formed in a foil shape having a thickness of 10 to 40 μm on the upper and lower surfaces of the base 2 after embedding the through metal body 3 in the through hole of the base 2. The copper plate 4 can be laminated and heated to be joined. When laminating the foil-like brazing material 15 with the substrate 2 and the copper plate 4, it is more preferable that the brazing material 15 does not entrain air because the brazing material 15 does not entrain air and the voids can be further reduced.

  The material of the penetrating metal body 3 and the material of the copper layer 4 (4a, 4b) bonded to the upper and lower surfaces of the base 2 and the penetrating metal body 3 are not limited to pure copper. It may be an alloy. Such an alloy containing copper as a main component is an alloy containing more than 50% by mass of copper. For example, a copper-tungsten alloy, a copper-molybdenum alloy, brass, or the like is used. Similarly, the copper impregnated in the substrate 2 is not limited to pure copper, but may be an alloy mainly composed of copper similar to the through metal body 3 and the copper layers 4 (4a, 4b).

  The arithmetic average roughness Ra of the surface of the copper layer 4a on the upper surface side of the heat radiating member 1, that is, the mounting portion 10 side on which the electronic component 11 is mounted, is preferably a smooth surface of Ra ≦ 30 μm. When Ra> 30 μm, voids tend to occur in the bonding material when the electronic component 11 is bonded and fixed to the mounting portion 10 via a bonding material such as glass, resin, or brazing material. The void generated in the bonding material not only lowers the bonding strength between the electronic component 11 and the heat radiating member 1, but also inhibits heat conduction between the electronic component 11 and the heat radiating member 1, and the electronic component storage package 8. And tends to reduce the heat dissipation of the electronic device 14.

  In addition, the arithmetic average roughness Ra of the surface of the copper layer 4b on the lower surface side of the heat dissipation member 1, that is, the side opposite to the mounting portion 10 on which the electronic component 11 is mounted, is preferably Ra ≦ 30 μm. Usually, the electronic component storage package 8 is connected to a support substrate made of a metal body such as aluminum or copper or a ceramic body having high thermal conductivity by screwing or using a molten metal such as solder or a brazing material. . At this time, when the arithmetic average roughness Ra of the lower surface of the copper layer 4b on the lower surface of the base 2 is Ra> 30 μm, it is difficult to sufficiently bring the electronic component storage package 8 and the support substrate into close contact with each other. Air gaps and voids are likely to occur between them, and as a result, the heat generated in the electronic component 11 may not be efficiently transferred from the electronic component storage package 8 to the support substrate. Therefore, the lower surface, which is the outer surface of the lower copper layer 4b, is preferably a smooth surface with Ra ≦ 30 μm so that good adhesion to the support substrate can be obtained.

  If the thickness of each of the copper layers 4a and 4b is greater than 800 μm, the stress generated due to the difference in thermal expansion between the base 2 and the copper layers 4a and 4b tends to increase, so that sufficient bonding strength cannot be obtained. It is desirable to keep Further, if the thickness of the copper layers 4a and 4b is 50 μm or more, the heat generated by the operation of the electronic component 11 is sufficiently spread in the plane direction of the copper layers 4a and 4b. It is desirable to set it to 50 μm or more.

  Also, the copper layers 4 (4a, 4b) bonded to the upper and lower surfaces of the base 2 of the heat radiating member 1 are formed on the upper and lower surfaces at least in the same area as the bottom surface of the recess 5a made of the heat radiating member 1 and the frame body 5. 1 is sufficient, and it is not always necessary to cover the entire upper and lower surfaces of the heat dissipating member 1 as shown in FIG.

  Preferably, as shown in FIG. 5, the upper copper layer 4a located outside the frame 5 is thinner than the remaining copper layer 4a. In this case, the frame 5 is attached to the inner side of the outer peripheral end of the upper surface of the heat radiating member 1.

  Thus, the thermal conductivity difference between the heat radiating member 1 and the frame body 5 is reduced by reducing the copper ratio in the heat radiating member 1 while maintaining good thermal conductivity by the thick copper layer 4a around the mounting portion 10 of the heat radiating member 1. Can be reduced. Therefore, when the heat radiating member 1 and the frame 5 are joined, the lower surface of the heat radiating member 1 can be effectively prevented from warping due to the difference in thermal expansion coefficient between the heat radiating member 1 and the frame 5. Therefore, it is possible to efficiently conduct heat from the heat radiating member 1 to the external substrate by maintaining the flatness of the substrate and improving the adhesion to the external substrate. As a result, the heat dissipation of the electronic component housing package 8 can be increased by the good heat conductivity of the heat dissipating member 1 and the highly efficient heat conduction to the external substrate.

  In the case where a screwing portion for screwing and fixing to the support substrate is provided in a portion located outside the frame body 5 of the heat radiating member 1, the stress when screwing and fixing to the screwing portion is the thickness of the copper layer 4a. It is possible to make it difficult to be transmitted to the frame 5 by being blocked at the part where the height changes.

  The distance between the outer surface of the frame 5 and the outer peripheral end of the heat radiating member 1 and the thickness ratio between the copper layer 4a on the upper surface side located on the outer side of the frame 5 and the remainder thereof are as follows: It may be adjusted as appropriate in consideration of the difference in thermal expansion.

  Further, if the thickness of the copper layers 4a and 4b on the inner side of the outer surface of the frame body 5 is greater than 800 μm, the stress generated by the difference in thermal expansion between the base 2 and the copper layers 4a and 4b increases, and sufficient bonding strength is obtained. Since there is a tendency not to be obtained, it is desirable to set it to 800 μm or less. Further, if the thickness of the copper layers 4a and 4b is 50 μm or more, the heat generated by the operation of the electronic component 11 is sufficiently spread in the plane direction of the copper layers 4a and 4b. It is desirable to set it to 50 μm or more.

  The frame body 5 of the present invention is a square frame-like frame body 5 in which the first, third, second and fourth side walls are connected in order, and the side portions of the pair of opposed frame bodies 5 are respectively shown. The lower surfaces of the first and second side walls are located outside the penetrating metal body 3 (see FIG. 1), and have third and fourth sides respectively having the side portions of the other pair of opposing frame bodies 5. Since the lower surface of the side wall overlaps the end of the penetrating metal body 3 in plan view (see FIG. 2), the boundary portion of the heat radiating member 1 between the penetrating metal body 3 and the base 2 having a relatively low strength is used as the frame body 5. It is possible to reinforce the heat dissipating member 1 by covering with a part of it, and to effectively prevent the heat dissipating member 1 from warping or deforming. The end portion of the through metal body 3 is a range within 10% of the length of the through metal body 3 from the outer side of the through metal body 3, and the lower surfaces of the third and fourth side walls are within this range. It arrange | positions so that it may overlap in.

  Further, when the frame body 5 has, for example, a hexagonal frame shape, for example, the lower surfaces of the pair of opposed side walls are located outside the through metal body 3 and the side walls adjacent to the pair of opposed side walls. What is necessary is just to make it the state which has overlapped with the edge part of the penetration metal body 3 by planar view.

  It is preferable that the wiring conductor 6 is not formed in the portion of the frame body 5 that covers the boundary portion between the through metal body 3 and the base 2. Thereby, the strength of the frame body 5 covering the boundary portion between the through metal body 3 and the base body 2 can be increased without reducing the strength of the frame body 5 by the wiring conductor 6. It is possible to more effectively prevent the frame body 5 from being cracked by the stress generated by the difference in thermal expansion from the base 2.

  Further, the copper layer 4 may be annealed by heating the heat dissipating member 1 to about 780 ° C. By annealing the copper layer 4, the ductility of the copper layer 4 is increased, and the thermal stress caused by the difference in thickness between the upper copper layer 4a and the lower copper layer 4b is reduced. The distortion which arises can be suppressed. In addition, thermal conductivity is hardly impaired by annealing the copper layer 4.

  Furthermore, preferably, as shown in FIG. 4, the heat radiating member 1 may have a side metal layer 4 c attached to the outer surface of the base 2. With this configuration, the heat generated from the electronic component 11 that has been transmitted from the central part of the copper layer 4a on the upper surface side of the heat radiating member 1 to the outer peripheral part on the lower surface side of the heat radiating member 1 on the side surface of the base 2 through the side metal layer 4c. Heat can be dissipated and the temperature difference between the central portion and the outer peripheral portion of the copper layer 4a on the upper surface side can be increased, so that the heat conduction of the copper layer 4a on the upper surface side can be efficiently performed. it can. Then, by placing and fixing the heat radiating member 1 on an external electric circuit board, a support board, an external heat radiating plate, etc., the heat generated from the electronic component 11 is efficiently dissipated to the external electric circuit board on the lower surface of the heat radiating member 1. Can be made. As a result, the electronic component 11 can be efficiently cooled and operated normally and stably over a long period of time.

  The side metal layer 4c does not have to be applied over the entire circumference of the side surface of the substrate 2, and the side metal layer 4c in contact with the copper layer 4a on the upper surface side and the copper layer 4b on the lower surface side at least partially. It only has to be attached. For example, when the heat radiating member 1 is a quadrangle, the side metal layer 4c in contact with the copper layer 4a on the upper surface side and the copper layer 4b on the lower surface side should be attached on at least two side surfaces facing each other. . Also in this configuration, the heat generated from the electronic component 11 can be dissipated sufficiently efficiently from the lower copper layer 4b.

  Further, the thickness of the side metal layer 4c is such that the distance from the electronic component 11 is larger than that of the copper layer 4a on the upper surface side, and does not require a large amount of heat transfer. It is possible to suppress the thermal expansion of the heat radiating member 1 from increasing.

  Further, the surface roughness of the side metal layer 4c is preferably rougher than the surface roughness of the copper layer 4a. With this configuration, the amount of heat dissipated directly from the surface of the rough side metal layer 4c to the outside can be increased, and the heat dissipating property of the heat radiating member 1 can be further enhanced.

  The side metal layer 4c is preferably made of a material having high thermal conductivity such as copper, silver, or a silver-copper alloy and having excellent thermal conductivity. The side metal layer 4c is attached to the base 2 by the same method as that for the upper surface copper layer 4a and the lower surface copper layer 4b, or the heat radiating member 1 and the frame 5 are bonded and fixed. When the brazing material used is a brazing material such as silver brazing or silver-copper brazing, the brazing material may be realized by brazing the brazing material to the side surface of the base 2. .

  Further, preferably, as shown in FIG. 6, the frame 5 is joined to the heat radiating member 1 via a metal frame-like member 9. With this configuration, the frame-shaped member 9 can absorb stress due to thermal expansion between the heat radiating member 1 and the frame 5, and the frame 5 is cracked or the frame 5 is peeled off from the heat radiating member 1. Can be effectively prevented, and heat can be conducted from the copper layer 4a on the upper surface side of the heat radiating member 1 to the frame-like member 9 so that the heat can also be radiated from the outer surface of the frame-like member 9. Can be further enhanced.

  The frame-like member 9 is made of a metal such as an iron-nickel alloy, an iron-nickel-cobalt alloy, or a material obtained by impregnating copper into a sintered body made of tungsten or molybdenum. Preferably, the material is the same as that of the base 2 of the heat dissipation member 1. Thereby, the thermal expansion of the copper layer 4a is effectively suppressed by sandwiching the copper layer 4a having a relatively large thermal expansion coefficient between the frame-shaped member 9 and the base body 2 having the same thermal expansion coefficient as that of the frame body 5, thereby reducing the stress. Can be effectively mitigated.

  If the frame-shaped member 9 is made of, for example, a material made by impregnating copper into a sintered body made of tungsten, a tungsten powder having a particle size of 5 to 40 μm is pressed into a flat plate shape, A porous sintered body is formed by sintering in an atmosphere of 1300 to 1600 ° C., and this sintered body is impregnated with 10 to 50% by mass of copper. The frame-shaped member 9 is formed by performing a punching process on the center so that

  Further, the thickness of the frame-shaped member 9 is preferably 40% or more of the thickness of the frame body 5. As a result, the stress due to the difference in thermal expansion coefficient between the frame 5 and the heat radiating member 1 can be effectively relieved, the outer surface of the frame member 9 can be increased, and the heat dissipation from the outer surface of the frame member 9 can be improved. it can.

  The frame-shaped member 9 preferably has an outer peripheral end located outside the outer surface of the frame body 5. Thereby, the exposed area of the outer surface of the frame-shaped member 9 can be further increased, heat is conducted from the copper layer 4a on the upper surface side of the heat radiating member 1 to the frame-shaped member 9, and from the outer surface of the frame-shaped member 9. Heat can be radiated more efficiently.

  Thus, the electronic component 11 is bonded and fixed to the mounting portion 10 of the heat radiating member 1 of the electronic component storage package 8 via the bonding material made of glass, resin, brazing material, etc., and FET, LD, LED, IC. , Each electrode of the electronic component 11 such as a capacitor is electrically connected to a predetermined wiring conductor 6 via a bonding wire 12, and then the electronic component 11 is placed inside a recess 5 a composed of the heat radiating member 1 and the frame 5. An electronic resin 11 is filled with a sealing resin such as an epoxy resin so as to cover the cover, or a cover body 13 made of resin, metal, ceramics or the like is covered on the upper surface of the frame body 5 so as to cover the recess 5a. By attaching and enclosing the electronic component 11, the electronic device 14 as a product is obtained.

  Next, samples were prepared as follows, and the electronic component storage package of the present invention shown in FIG. 3 was evaluated.

  First, as the heat radiating member 1 shown in FIG. 3, a member having a size of 34 mm × 17.4 mm and a thickness of 1.9 mm was prepared.

  The base 2 of the heat radiating member 1 was formed of a material obtained by impregnating a sintered body made of tungsten with 20% by mass of copper, and its thickness was 1.00 mm. Moreover, the copper plate 4 (4a * 4b) of the thermal radiation member 1 was 0.45 mm in thickness, respectively.

  The through metal body 3 is formed by processing copper into a size of 20 mm × 5 mm × 1 mm, and inserting the through metal body 3 into a punched hole having a size of 20.1 mm × 5.1 mm provided in the center of the base 2. The copper plate 4 (4a, 4b), the base body 2 and the penetrating metal body 3 are joined together with a brazing material 15 made of a B silver alloy (72.0% by mass of silver and 28.0% by mass of copper), and the penetrating metal body 3 and the base 2 They were joined by filling them with brazing material 15. At this time, the brazing material 15 having the same plane size as that of the base 2 and the brazing material 15 having three different thicknesses of 0.50 mm, 0.40 mm, and 0.30 mm was manufactured.

These heat dissipating members 1 are made of a frame-like Fe—Ni—Co alloy (thermal expansion coefficient is 18.3 × 10 ⁻⁶ / ° C.) or alumina having an outer size of 34 mm × 17.4 mm × 1 mm and an inner size of 20 mm × 9.4 mm. A frame body 5 made of ceramics (thermal expansion coefficient: 8.0 × 10 ⁻⁶ / ° C.) is joined with a brazing material made of a B silver alloy (silver is 72.0 mass%, copper is 28.0 mass%), and an electronic component storage package 8 Got. Thereafter, the brazing material in a cross section parallel to the main surface of the base 1 of the brazing material 15 for joining the copper plate 4 (4a, 4b) of the heat radiating member 1 to the base 1 and the penetrating metal body 3 using an X-ray transmission device. The area ratio occupied by voids generated by 15 voids was measured.

  Further, a heater chip (heat generating component) was mounted on the electronic component storage package 8 instead of the electronic component, and the heat dissipation of the heat radiating member 1 was evaluated by operating the heater chip.

The results of the above evaluation tests are shown in Table 1. Table 1 shows the relationship between the area ratio of the voids in the cross section parallel to the main surface of the base 1 of the brazing material 15 in the electronic component storage package 8 and the heat dissipation property.

  As is clear from the results shown in Table 1, the area ratio of the voids of the brazing material 15 in the cross section parallel to the main surface of the base 2 of the heat radiating member 1 varies depending on the thickness of the brazing material 15. It was also found that there is a clear relationship between this area ratio and heat dissipation.

  And when the area ratio which the space | gap occupies in the cross section parallel to the main surface of the base | substrate 1 of the brazing material 15 is 15% or less, the heat dissipation is favorable and the heat | fever generated from the electronic component 11 is efficiently carried out outside. It has been found that the thermal conductivity is excellent, exceeding 300 W / mK, which is a thermal conductivity that can dissipate and operate the electronic component 11 normally. On the other hand, when the area ratio occupied by the air gap is larger than 15%, the heat dissipation is less than 300 W / mK and the heat generated from the electronic component 11 cannot be efficiently dissipated to the outside. It was found that it could not operate normally.

  The present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the scope of the present invention. For example, in order to efficiently dissipate heat generated in the electronic component 11 from the heat radiating member 1 to the atmosphere, heat radiating fins are brazed to the copper layer 4b bonded to the base 2 of the heat radiating member 1 and the lower surface of the through metal body 3. The heat radiating fins may be integrated with the heat radiating member 1 by joining the heat radiating member 1 and the like, and thereby the heat generated by the operation of the electronic component 11 is absorbed by the heat radiating member 1 and diffused into the atmosphere. Can be further improved.

It is sectional drawing which shows an example of embodiment of the electronic component storage package of this invention, and the electronic device of this invention using the same. FIG. 2 is a side sectional view of the electronic component storage package of FIG. 1 and the electronic device of the present invention using the same. It is sectional drawing which shows the other example of embodiment of the electronic component storage package of this invention, and the electronic device of this invention using the same. It is sectional drawing which shows the other example of embodiment of the electronic component storage package of this invention, and the electronic device of this invention using the same. It is sectional drawing which shows the other example of embodiment of the electronic component storage package of this invention, and the electronic device of this invention using the same. It is sectional drawing which shows the other example of embodiment of the electronic component storage package of this invention, and the electronic device of this invention using the same. It is sectional drawing which shows the example of the conventional electronic device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ..... Radiation member 2 ....... Base | substrate 3 ...... Through-metal body 4, 4a, 4b ... Copper layer 4c ... ...... Side metal layer 5 ... Frame 5a ... Recess 6 ... Wiring conductor 8 ... ..Electronic component storage package 9 ... Frame-shaped member
10 ・ ・ ・ ・ ・ ・ ・ ・ ・ Mounting part
11 ・ ・ ・ ・ ・ ・ ・ ・ ・ Electronic parts
14 .... Electronic devices
15, 15a, 15b ... brazing material

Claims (9)

A flat plate-like heat radiating member having an electronic component mounting portion at the center of the upper surface, a rectangular frame attached to the upper surface of the heat radiating member so as to surround the mounting portion, and a pair of opposing frames A plurality of wiring conductors led from the inner surface of the side portion to the outer surface, and the heat dissipating member is an upper surface of a central portion of a frame-like base body formed by impregnating a sintered body made of tungsten or molybdenum with copper A through metal body made of copper or an alloy containing copper as a main component is embedded from the bottom surface to the bottom surface, and a copper layer is formed to cover the upper and lower surfaces of the base body and the through metal body, and the frame body The third and fourth side surfaces having lower surfaces of the first and second side walls each having a pair of opposing side portions are located outside the penetrating metal body and have another pair of opposing side portions, respectively. Plane view of the bottom of the side wall Electronic component storing package, characterized in that overlaps with an end portion of the through-metal body. 2. The electronic component according to claim 1, wherein each sectional area in a longitudinal section of each of the third and fourth side walls of the frame body is larger than each sectional area in a longitudinal section of the first and second side walls. Storage package. 3. The electronic component storage package according to claim 1, wherein the copper layer is formed by bonding a copper plate via a brazing material made of an alloy containing silver as a main component. 4. The electronic component storage package according to claim 3, wherein the brazing material has an area ratio of 15% or less in a cross section parallel to the main surface of the base body. The electronic component storage package according to any one of claims 1 to 4, wherein the heat radiating member has a side metal layer attached to an outer surface of the base. 6. The electronic component storage package according to claim 1, wherein the copper layer on the upper surface side has a portion whose thickness is located outside the frame body is thinner than the remaining portion. 7. 7. The electronic component storage package according to claim 1, wherein the frame body is joined to the heat dissipation member via a metal frame member. The electronic component storage package according to claim 7, wherein an outer peripheral end of the frame-shaped member is positioned outside an outer surface of the frame body. The electronic component storage package according to any one of claims 1 to 8, the electronic component mounted on the mounting portion and having an electrode electrically connected to the wiring conductor, and an upper surface of the frame body An electronic device comprising: a lid attached so as to cover the electronic component; or a sealing resin filled inside the frame so as to cover the electronic component.

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