JPH06209175A - Heat conduction method - Google Patents

Abstract

PURPOSE:To conduct the heat generated by electric components to a board frame by using a heat conduction member, without interposing a mounting board. CONSTITUTION:A mounting board 10 provided with a square hole 11 is constituted. A board frame 15 is fixed to the mounting board 10 A flat plate 18 for electromagnetic shielding which applies the board frame 15 to a retaining surface and covers both surfaces of the mounting board 10 is constituted. A heat conduction member 7 which directly conducts the heat generated from the electric component 1 to the flat plate 18 for electromagnetic shielding is coupled to the electric component 1 and the flat plate 18 for electromagnetic shielding, through the square hole 11 of the mounting board 10. Thereby the heat generated from the electric component is directly conducted to the board frame, so that the temperature rise of electric components and the mounting board can be suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat conduction method for mounting a high heat generating electric component such as an LSI on a substrate.

[0002]

2. Description of the Related Art FIG. 8 is a diagram showing an example of a conventional heat conduction method according to the present invention. 8A is a diagram showing the shape of an electric component, FIG. 8B is a diagram showing the substrate shape, and FIG. 8C.
[Fig. 3] is a diagram showing an implementation form.

In the figure, 1 is an electrical component, 2 is a lead molded for mounting the electrical component 1 on a substrate, 3 is a frame made of a heat conductive aluminum material, 4 is a mounting substrate, and 5 is for soldering the lead 2. Is a heat conductive sheet sandwiched between the electric component 1 and the mounting substrate 4. Figure 8 (c)
The shaded area is the heat conductive sheet 6, both sides of which are adhesive and have a function of conducting the heat of the electric component 1 to the mounting board 4.

Next, a method of mounting components will be described with reference to FIG. The heat conductive sheet 6 is bonded onto the mounting substrate 4. The electric component 1 is adhered from above, and the leads 2 and the lead pads 5 are fixed by soldering or the like. Next, the frame 3 is fixed to the mounting board 4.

[0005]

The conventional heat conduction method is as follows.
The heat of the electric component 1 is generated from the lead 2 and the heat conductive sheet 6,
This is a method in which the frame 3 is conducted through the mounting substrate 4.

However, in recent years, large-scaled LSIs and high-speed processing operations have become common, and the heat generation per stone reaches several watts, and heat cannot be fully conducted only by conventional heat countermeasures through the mounting board 4. As a result, the temperature of the electric component 1 and the temperature of the mounting substrate 4 rise, and there is a problem that it is difficult to keep the temperature within the upper limit of the allowable temperature.

The present invention has been made in order to solve the above problems, and an aluminum material serving as a cover for the mounting board 4 by an aluminum member having good thermal conductivity from the electric component 1 to generate heat from the electric component 1. It is intended to conduct to the board frame through the electromagnetic shielding flat plate such as.

Further, the mounting board 4 is plated with a heat conductive material, and an aluminum member having a good heat conductivity is used for the plated portion on the opposite side of the mounting surface of the electric component 1 or the mounting surface side. The purpose is to conduct the heat generated from the electric component 1 to the substrate frame through an electromagnetic shield flat plate made of aluminum or the like which serves as a cover.

[0009]

A heat conduction method according to the present invention is a square hole of a mounting board with a substrate frame, in which a square hole having a size smaller than the package size of the electric component 1 is formed in a portion where the electric component 1 is mounted. In addition, the rectangular heat conductive flat plate having the thickness of the gap between the package bottom surface of the electric component 1 and the surface of the mounting board and the same size as the package size of the electric component 1 and the square hole of the mounting board, and the electric component 1 Of the electric component 1 that is inserted into the rectangular heat conductive flat plate having a thickness up to the electromagnetic shield flat plate on the opposite side of the mounting board surface, and contacts the periphery of the mounting board surface square hole when inserted. Fix the four corners of the four sides of the flat plate part of the heat conductive member on the package size side with flat screws, apply the heat conductive adhesive to the fixed surface of the heat conductive member facing the package of the electric component 1, and apply the heat conductive adhesive on the applied flat surface. The lead 2 molded after bonding the electric component 1 is fixed to the lead pad 5 by soldering, etc., and the electromagnetic shield flat plate is fixed to the board frame with a flat screw. Finally, heat conduction is performed on the opposite side of the electric component mounting. A flat plate for electromagnetic shielding that is in contact with a member is fixed with a flat screw.

Further, both sides of the mounting board are subjected to thermal conductive plating in a range corresponding to the package area of the electric component 1, and the thermal conductive plating on both sides is connected by a plurality of through holes penetrating the mounting board, Molding of the electric component 1 after adhering a heat conductive sheet 6 having a thickness corresponding to the thickness of the gap between the electric component 1 and the surface of the mounting substrate on the heat conductive plated portion on the mounting surface side of the electric component 1 of the mounting substrate. Then, the lead 2 is fixed to the lead pad 5 by soldering or the like, and then the heat conductive member having the same shape as the heat conductive member is fitted to the conductive plated portion on the opposite side of the mounting substrate where the electric component 1 is mounted. It is fixed, and finally the heat conducting member and the electromagnetic shield flat plate are fixed with flat screws.

Further, heat conductive plating is applied to the area of the mounting board on which the electric component 1 is mounted, and the heat conductive plating is applied outside each gap of the lead 2 fixing lead pad 5 of the electric component 1 on the mounting board. Radially drawn out, the drawn out heat conductive plating is joined by a rectangular band-shaped heat conductive plating surrounding the mounting area of the electric component 1, and the heat conductive plated portion in the range where the electric component 1 is mounted is adhesive. After bonding the heat conductive sheet 6 and further bonding the electric component 1, the lead 2
Is fixed to the lead pad 5 by soldering or the like, and then the hollow conductive member having the hollow shape of the heat conductive member and the portion in contact with the surface of the mounting substrate conforms to the strip-shaped heat conductive plating is used as the electric component 1. From the mounting surface side, the band-shaped heat conductive plating is matched and fixed with a flat screw, and finally, the hollow heat conductive member and the electromagnetic shield flat plate on the mounting side of the electric component 1 are fixed with a flat screw.

[0012]

As described above, the heat-conducting member passes through the square holes of the mounting board so that the heat generated in the electric component 1 can be conducted from the package bottom surface of the electric component 1 to the substrate frame through the electromagnetic shielding flat plate.

Further, both surfaces of the mounting board on which the electric component 1 is mounted are subjected to heat conductive plating coupled by through holes, and the heat conducting member is fixed to the surface of the mounting board opposite to the mounting of the electric component 1. , So that the heat generated by the electric component 1 can be conducted to the substrate frame through the electromagnetic shield flat plate.

Further, the package bottom surface portion and the outer peripheral portion on which the electric component 1 of the mounting board is mounted are subjected to heat conductive plating, and the cavity-shaped heat conductive member is fixed on the outer peripheral band-shaped heat conductive plating. , So that the heat generated by the electric component 1 can be conducted to the substrate frame through the electromagnetic shield flat plate.

[0015]

【Example】

Example 1. 1A and 1B show the shape of a member for heat conduction according to an embodiment of the present invention. FIG. 1A is a perspective view, FIG. 1B is a side view, and FIG. 1C is a top view. It is a figure.

In the figure, 7 is a heat conducting member, 8 is a screw hole for fixing to a mounting board, and 9 is a screw hole for fixing to a flat plate for electromagnetic shielding.

2A and 2B show a substrate shape according to an embodiment of the present invention. FIG. 2A is a top view of a mounting substrate, and FIG. 2B is a cross-sectional view of a section A of FIG. 2A. FIG.

In the figure, 10 is a mounting board showing an embodiment of the present invention, 11 is a square hole through which the heat conducting member 7 is passed, and 12 is a screw hole corresponding to the screw hole 8.

FIG. 3 shows the assembling method of FIGS. 1 and 2. FIG. 3A is a diagram showing an assembly procedure, FIG.
(B) is a figure showing after assembly.

In the figure, 13 is a screw hole 8 and a screw hole 12
, 14 is a nut for fixing the flat screw 13, 15 is a board frame for fixing the mounting board 10, 16
Is a square screw for fixing the mounting substrate 10 and the substrate frame 15,
Reference numeral 17 is a nut, 18 is a flat plate for electromagnetic shield that covers the mounting board 10 from both sides with the board frame 15 as a supporting surface, 1
9 is a flat screw for fixing the substrate frame 15 and the electromagnetic shield flat plate 18, 20 is a flat screw for fixing the heat conducting member 7 by the screw hole 9, and 21 is applied to the mounting surface of the heat conducting member 7 on which the electric component 1 is mounted. It is a heat conductive adhesive. Thermal conductive adhesive 21
Is applied as shown by the shaded area in FIG.

Next, the assembly procedure will be described. The heat conducting member 7 is inserted into the square hole 11 of the mounting substrate 10 along the arrow B. After insertion, align screw holes 8 and 12 and flat screw 1
The heat conducting member 7 and the mounting substrate 10 are fixed with 3 and the nut 14. Next, the heat conductive adhesive 21 is applied to the heat conductive member 7, the electric component 1 is bonded onto the heat conductive adhesive 21 along the arrow C, and the leads 2 are fixed to the lead pads 5 by soldering. Further, the board frame 15 is fixed to the mounting board 10 with square screws 16 and nuts 17, and the electromagnetic shield flat plate 18 is fixed to the board frame 15 with flat screws 19 along the arrow D. The flat plate 18 is fixed with the screw holes 9 and the flat screws 20.

The heat generated by the electric component 1 is generated by the heat-conducting adhesive 21, the heat-conducting member 7, and the arrows shown in FIG.
The board frame 15 is passed through the electromagnetic shield flat plate 18.
Can be conducted to.

Example 2. In the above-described first embodiment, the conventional mounting board 4 is provided with the mounting board 10 having the square holes 11 through which the heat conducting members 7 are inserted, and the electromagnetic shield flat plate 18 on the side opposite to the mounting surface of the electrical component 1 of the mounting board 10. Through the board frame 15
In this embodiment, the heat is conducted to the board frame 15 without forming the square hole 11 through which the heat conducting member 7 is passed.

4A and 4B are views showing a substrate shape according to an embodiment of the present invention. FIG. 4A is a top view and FIG. 4B is a cross-sectional view of a cross section A of FIG. 4A. is there.

In the figure, 22 is a mounting board showing an embodiment of the present invention, and 23 is a heat conductive plating such as a solder material applied in a rectangular area shown by hatching in FIG. 4 (a). The heat conductive plating 23 is applied to both surfaces of the mounting substrate 22 as shown in FIG. 24 is heat conductive plating 2
The circles are all arranged except the circles at the four corners of the circle 3, and are through holes having heat conductivity for thermally conductively coupling the heat conductive platings 23 arranged on both surfaces of the mounting substrate 22. The through holes 24 are finally filled with solder or the like to improve heat conduction. Reference numeral 25 is a screw hole for fixing the heat conducting member 7 and the mounting substrate 22.

FIG. 5 shows the assembly procedure. 26
Is a flat screw for fixing the mounting substrate 22 and the heat conducting member 7.

Next, the assembly procedure will be described. The heat conducting member 7 is fixed to the mounting board 22 from the side opposite to the mounting surface of the electric component 1 using a flat screw 26. Next, the heat conductive sheet 6 is bonded onto the heat conductive plating 23 on the mounting surface side of the electric component 1. The electric component 1 is adhered from above, and the lead 2 is fixed to the lead pad 5 by soldering or the like. Further, the mounting substrate 22 and the substrate frame 15 are fixed with square screws 16, and then the substrate frame 15, the heat conducting member 7 and the electromagnetic shield flat plate 18 are fixed with flat screws 19 and 20.

The heat of the electric component 1 is generated by the heat conducting sheet 6, the heat conducting plating 23 on the side where the electric component 1 is mounted, the through hole 24, and the heat conducting plate on the side of the heat conducting member 7 as shown by arrows and in FIG. The heat can be conducted to the substrate frame 15 via the heat conducting member 23, the heat conducting member 7 and the electromagnetic shield flat plate 18.

Example 3. FIG. 6 is a view showing the shape of the heat conducting member applied to this embodiment. Example 1 and Example 2
Unlike the heat conduction member 7 of FIG.

In the figure, 27 is a hollow heat conducting member, 2
8 is a screw hole for fixing to the electromagnetic shield flat plate 18,
29 is a screw hole for fixing to the mounting board of this embodiment.

FIG. 7 is a view showing the assembling procedure of this embodiment. FIG. 7A shows the shape of the mounting board showing this embodiment,
FIG. 7B shows an example of assembly.

In the figure, 30 is a mounting substrate showing an embodiment of the present invention, 31 is the screw hole 2 of the hollow heat conducting member 27.
9 is a screw hole aligned with 9, and 32 is a heat conductive plating disposed so as to avoid the lead pad 5. The heat conductive plating 32 is the portion shown by the hatched portion in FIG.
Reference numeral 33 is a square screw for fixing the mounting substrate 30 and the hollow heat conduction member 27.

Next, the assembling procedure will be described with reference to FIG. After adhering the heat conductive sheet 6 to the mounting substrate 30,
The electric component 1 is adhered, and the lead 2 is fixed to the lead pad 5 by soldering or the like. Next, the hollow heat conduction member 27 is placed on the heat conductive plating 32 from the upper part of the electric component 1, the screw holes 31 and the screw holes 29 are aligned, and then fixed with the square screws 33. Further, the electromagnetic shield flat plate 18 is fixed to the substrate frame 15 and the hollow heat conduction member 27 with flat screws 19 and 20.

The heat generated by the electric component 1 is generated by the heat conductive sheet 6 and the heat conductive plating 3 as shown by arrows and in FIG.
2. The heat can be conducted to the substrate frame 15 through the hollow heat conduction member 27 and the electromagnetic shield flat plate 18.

In the above description, the electrical component 1 is L
Although a flat package such as SI has been described as an example, it is needless to say that the present invention can be applied to components such as a transistor having high heat generation and components of a dual-in-package type.

[0036]

Since the present invention is constructed as described above, it has the following effects.

The bottom surface of the package of the electric component 1 having a high heat generation is directly adhered to the heat conducting member 7 penetrating the square hole 11 of the mounting board 10, and the board is provided through the electromagnetic shield flat plate 18 on the surface opposite to the board mounting of the electric component 1. Heat can be conducted to the frame 15. Along with this, it is possible to prevent the temperature of the electric component 1 and the mounting board 10 from rising.

Further, the heat conducting member 7 is fixed to the surface of the mounting board 22 having the heat conductive plating 23 connected to the through holes 24 on both surfaces, on which the electric component 1 is mounted, and the electromagnetic shield flat plate 18 is interposed therebetween. The heat can be conducted to the substrate frame 15. Accordingly, the electric component 1 and the mounting board 2
It is possible to prevent the temperature of 2 from rising.

In addition, the band-shaped thermal conductivity of the mounting substrate 30 in which the heat conductive plating 32 is applied to the package bonding surface on the mounting surface side of the electric component 1 and the gap between the lead pad 5 and the outer band area of the lead pad 5. The hollow heat conductive member 27 is fixed to the plating 32, and the board frame 1 is mounted from the mounting surface side of the electric component 1 via the electromagnetic shield flat plate 18.
5 can conduct heat. Along with this, it is possible to prevent the temperature of the electric component 1 and the mounting substrate 30 from rising.

[Brief description of drawings]

FIG. 1 is a diagram showing the shape of a heat conducting member that is Embodiment 1 of the present invention.

FIG. 2 is a diagram showing a substrate shape which is Embodiment 1 of the present invention.

FIG. 3 is a diagram showing an assembling procedure according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a substrate shape which is Embodiment 2 of the present invention.

FIG. 5 is a diagram showing an assembling procedure according to the second embodiment of the present invention.

FIG. 6 is a diagram showing the shape of a heat conducting member that is Embodiment 3 of the present invention.

FIG. 7 is a diagram showing an assembling procedure of embodiment 3 of the present invention.

FIG. 8 is a diagram showing an example of a conventional heat conduction section method of a mounting board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrical component 2 Lead 3 Frame 4 Mounting board 5 Lead pad 6 Thermal conductive sheet 7 Thermal conductive member 10 Mounting board 15 Board frame 18 Electromagnetic shield flat plate 21 Thermal conductive adhesive 22 Mounting board 23 Thermal conductive plating 24 Through hole 27 Cavity Shaped heat conductive member 30 Mounting board 32 Thermal conductive plating

Claims (3)

[Claims] 1. An electric component in which leads for inputting and outputting electric signals from two or four opposite sides of an IC having a quadrilateral package are lead-molded for board mounting, and a package size of the electric component in a portion where the electric component is mounted. Smaller size mounting board with square holes, thermally conductive board frame that is placed around the mounting board to fix the mounting board, and heat conduction that is fixed to the board frame by covering the mounting board from both sides. Rectangular electromagnetic conductive flat plate, which has the thickness of the gap between the package bottom surface of the electric component and the surface of the mounting board and has the same size as the package size of the electric component and the same size as the square hole of the mounting board. A heat conductive member in the form of a square heat conductive flat plate having a thickness up to the flat plate for electromagnetic shield on the side opposite to the mounting substrate surface of the electrical component, which is connected about each center as an axis, the mounting substrate and the substrate It is composed of square screws that fix the frame and flat screws that fix the heat conductive member to the mounting board and the electromagnetic shield flat plate.The board frame is fixed to the mounting board with the square screws, and then from the mounting side of the mounting board electrical components. Insert the flat plate side that matches the square hole size of the heat conducting member, and fix the four corners of the four sides that contact around the square hole on the mounting board surface of the electric component package size flat plate side of the heat conducting member when inserting, with flat screws,
After applying a heat conductive adhesive on the flat surface of the fixed heat conductive member facing the package of the electric component, and fixing the molded lead by mounting the electric component on the applied flat surface to the mounting board by soldering or the like, By fixing the electromagnetic shield flat plate to the board frame with flat screws, and by fixing the heat conducting member and the electromagnetic shield flat plate in contact with it with the flat screw on the side opposite to the electrical component mounting side A heat conduction method, comprising conducting from a conductive member to a substrate frame through a flat plate for electromagnetic shielding. 2. A mounting board, wherein both surfaces of the mounting board on which electric parts are mounted are subjected to thermal conductive plating in a range corresponding to a package area, and the thermal conductive plating on both surfaces is coupled by a plurality of through holes penetrating the mounting board. After mounting the electrical component and the mounting board on the mounting surface side of the electrical component with a thermal conductive sheet that has the thickness of the gap between the electrical component and the surface of the mounting substrate and is adhesive on both sides, use the molding lead of the electrical component as the mounting substrate. It is fixed by soldering or the like, and then the heat conductive member of the same shape as set forth in claim 1 is fixed to the conductive plated portion on the opposite surface of the mounting board on which the electric component is mounted. The flat plate for electromagnetic shield on the surface side is fixed with a flat screw, and the heat generated by the electric component is conducted to the substrate frame through the heat conductive sheet, the heat conductive plating, the heat conductive member, and the flat plate for electromagnetic shield. The heat conduction method according to item 1. 3. A heat conductive plating is applied to a range corresponding to a package area of a mounting surface of an electric component of a mounting board, and the heat conductive plating is radially outwardly drawn from each gap of the electric component forming lead pad on the mounting board. , The drawn out thermal conductive plating was joined by a rectangular band-shaped thermal conductive plating surrounding the electrical component mounting area, and the bottom surface of the electrical component package and the thermal conductive plated portion were bonded with an adhesive thermal conductive sheet. After that, the molding lead of the electric component is fixed to the mounting board by soldering or the like, and then the hollow shape of the heat conducting member described in claim 1 and the portion to be brought into contact with the surface of the mounting board match the band-shaped heat conducting plating. Such a hollow type heat conducting member is covered with the band-shaped heat conducting plating from the component mounting surface so as to cover the electric component and fixed with a flat screw, and further, the hollow type heat conducting member and the electric component. It is fixed to the electromagnetic shield flat plate on the mounting side with a flat screw, and the heat generated from the electric component is conducted to the substrate frame through the heat conductive sheet, the heat conductive plating, the hollow heat conductive member, and the electromagnetic shield flat plate. The heat conduction method according to item 1.