JP3479206B2 - Heat conductive spacer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat conducting member for promoting heat dissipation of a heat-generating electronic component in a circuit device.

[0002]

2. Description of the Related Art Conventionally, in order to promote heat dissipation from one or more, and often a plurality of semiconductor integrated circuit devices (ICs) or other heat-generating electronic components installed on a substrate such as a printed wiring board, One heat-conductive sheet made of heat-conductive silicon rubber or the like is brought into close contact with the heat-generating electronic components, and the other surface of each heat-conductive sheet is used as a common heatsink. For example, it has been performed in close contact with a metal chassis for a circuit device including the above substrate.

[0003]

When assembling the above-described circuit device in a line, one or a plurality of heat conducting sheets each having a shape (size) and a thickness that are not the same are previously formed on a substrate (for example, a substrate). Check the position of the prescribed heat-generating electronic component on the printed wiring board) and attach it accurately to the upper surface of the printed circuit board, and then attach the heat conduction sheet to the prescribed position on the chassis where the heat sink should be formed. The above-mentioned substrate on which the components are attached is attached. Therefore, it takes a lot of time and effort to find the position of a predetermined heat-generating electronic component on the substrate and to accurately attach the heat-conducting sheet on it.

An object of the present invention is to provide a heat-conducting sheet (spacer) which makes it possible to manufacture the above-mentioned circuit device while significantly reducing the labor required as a whole as compared with the prior art, and thus significantly reducing the manufacturing cost. It is to be.

[0005]

Means for Solving the Problems and Actions / Effects of the Invention A heat conducting spacer according to the present invention for solving the above problems is a substrate on which one or a plurality of heat-generating electronic components are installed. and a thermally conductive spacer interposed between the heat sink, at least one thermally conductive sheet and a predetermined shape and thickness so as to close contact with the substrate surface of the heat-generating electronic component near the support The support plate is integrally attached to a predetermined position of the plate, and the heat conduction shield of the support plate is attached.
A hole is provided in the part where the seat is not attached and the hole is used as a ventilation hole.
It is characterized by being used .

According to the heat conducting spacer of the invention described in claim 1, a predetermined heat conducting sheet can be brought into contact with the surface of the substrate in the vicinity of one or a plurality of heat generating electronic components on the substrate.
Since the heat conduction sheet is previously arranged on one support plate having a predetermined shape, it is possible to efficiently manufacture the heat conduction sheet on another line using an automatic machine. Further, as described above, since the heat conduction sheet is in contact with the substrate surface, the thickness of the heat conduction sheet should be substantially equal to the distance between the substrate and the support plate. Well, it can be manufactured without being influenced by the shape of the heat-generating electronic component.

[0007] thermal conductivity spacer of the invention recited in claim 2, Oh a thermally conductive spacer is interposed between the one or more heat generating electronic component and a heat sink disposed on a substrate
Then, a plurality of heat conduction sheets each having a predetermined shape and thickness so as to be brought into close contact with the heat-generating electronic component are integrally attached to a predetermined position of the support plate .
If the heat conduction sheet of the support plate is not attached,
It is characterized in that a hole is provided in the open portion and the hole is used as a ventilation hole .

The heat-conducting spacer according to the second aspect of the present invention is configured so that a predetermined heat-conducting sheet (spacer) can correspond to one or a plurality of heat-generating electronic components on the substrate in advance. Since the conductive sheet is arranged on one support plate having a predetermined shape, it can be efficiently manufactured in another line by using an automatic machine. The heat-conducting spacer of the present invention can be easily arranged in a predetermined positional relationship with respect to the heat-generating electronic component with the substrate and the heat sink, and it is sufficient to fix them.

Moreover, the heat conduction strip according to the first and second aspects.
The pacer has a hole in the support plate,
By providing holes at the corresponding positions of the
As a result, heat dissipation due to convection can be further promoted.

Support in the heat conducting spacer of the present invention
The plate can be a sheet for electrical insulation. Install the support plate for electrical insulation.
A sheet, that is, by making it electrically insulating,
The electronic circuit on the board is attached to the heat sink that is made of metal.
Safety can be guaranteed in an electrically insulating environment.
If the electrically insulating sheet is made of synthetic resin, the sheet can be manufactured inexpensively and easily, and a lightweight and electrically insulating sheet can be obtained. As the synthetic resin, for example, polyethylene terephthalate, polyethylene, polyimide or the like can be preferably used.

When the electrically insulating sheet is made of synthetic resin
Use a synthetic resin with a thermally conductive filler mixed in
You can also By mixing the heat conductive filler in the synthetic resin, the heat conductivity can be enhanced to the same level as that of the heat conduction sheet without any loss of electrical insulation.

The sheet for electrical insulation is a heat sink.
A metal surface layer may be provided on the surface on the side contacting with.

Provided in close contact with the electrically insulating sheet
The metal surface layer formed at least part of the heat sink
In the case of the electrical insulation sheet, the part close to the heat conduction sheet
Dispersion of heat in is advantageously carried out. Further, when a separate heat sink is used, the heat conducting spacer can more radiate heat to the heat sink even under a relatively low contact pressure to the heat sink. The metal surface layer can be provided by metal coating, vacuum vapor deposition, metal foil bonding, or the like.

Support in the heat conducting spacer of the present invention
The plate can also be made of a conductive material. By constructing the support plate with a sheet of a conductive material, an EMC effect (electromagnetic compatibility) can be obtained in addition to thermal conductivity. The conductive material in this case may be a metal material or E
A material mixed with carbon, carbon fiber, metal particles or the like as a material for enhancing the MC effect may be used.

Heat conduction used for the heat conduction spacer of the present invention
If the sheet is made of synthetic resin mixed with thermally conductive filler,
Good. As the heat conduction sheet , an elastic material containing rubber such as raw rubber, natural rubber, synthetic rubber (including vulcanized rubber and thermoplastic elastomer) mixed with a powdery heat conductive filler is used. Therefore, as compared with the case where a synthetic resin is used, the elasticity is high and the heat-generating electronic component can be easily attached. Specifically, for example, synthetic rubber such as silicone rubber, urethane rubber, styrene rubber can be preferably used as the rubber. Since the thermal conductivity is provided by mixing the thermal conductive filler, the thermal conductivity can be easily adjusted at low cost. When using ceramics such as alumina, beryllia, magnesia, silica fiber, zinc oxide, aluminum nitride, cordierite, aluminum titanate, transition metal oxide-based ceramics, etc. as the above-mentioned thermally conductive filler, electrical insulation is also kept high. Being advantageous. On the other hand, non-electrically insulating materials such as silver, copper, carbon black, graphite and carbon fiber can also be used. In addition, by pre-processing rough surface processing such as so-called wrinkling and sand blasting, the surface portion of this heat-conducting sheet that comes into contact with the surface of the electrically insulating sheet made of synthetic resin or the heat sink of metal , For the electrical insulation of the heat-conducting sheet, the heat conductivity is improved by increasing the area of contact between the contact surfaces when they are pressed and the property that both contact surfaces adhere to each other when pressed. It can be advantageously used for joining to a sheet or a heat sink.

In the heat conducting spacer of the present invention,
Install the heat conduction sheet from one side of the support plate into the hole provided in the holding plate.
By providing at least a part of the heat conduction sheet
Exposes the surface to the other side of the support plate, which allows heat transfer
Sheet can be used by directly contacting the heat sink
It

Dense the heat conduction sheet directly onto the heat sink.
Since it can be contacted, it does not transfer heat to the heat sink.
Can be done effectively.

In the heat conductive spacer of the present invention, the support plate is provided with a tongue-shaped projection piece formed by being bent toward the side where the heat sink is provided, and the heat sink is provided via the tongue-shaped projection piece. It can also be used by elastically contacting with .

When the tongue-shaped projection piece is provided , the support plate is stronger against the heat sink at the portion of the tongue-shaped projection piece, so that the support plate comes into further tight contact with the heat sink, so that the heat conduction is performed more effectively. The heat conducting spacer of the present invention is for heat conduction through an adhesive layer provided in advance on either the surface of the heat conducting sheet that contacts the supporting plate or the surface of the supporting plate that contacts the heat conducting sheet. The sheet and the electrically insulating sheet can be bonded together .

In the heat conducting spacer of the present invention , an adhesive layer is preliminarily provided on either one of the sheets in order to fix the heat conducting sheet and the supporting plate in a predetermined positional relationship in the manufacturing process of the heat conducting spacer. By applying the adhesive to the contacting portion of the sheet, the sheet provided with the pressure-sensitive adhesive layer and the other sheet can be attached to each other by pressure, and the production of the heat conductive spacer becomes easy.

The heat-conducting spacer of the present invention is provided between the heat-generating electronic component and a metal plate forming a heat sink integrally provided on a chassis to which a substrate having the heat-generating electronic component is mounted. To use under pressure
You can

A heat conductive spacer is pressed between the heat-generating electronic component and a metal plate forming a heat sink integrally provided on a chassis to which a substrate having the heat-generating electronic component is mounted. the use by interposing the adhesion of the heat conduction spacer for the said pyrogenic electronic component and a heat sink when using using a chassis board provided with the heat-generating electronic component, therefore the heat transfer coupling more fully Can be obtained easily and easily.

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION A heat conducting spacer according to a first embodiment of the present invention is shown in FIGS. 1 is a perspective view of a heat conducting spacer according to the first embodiment of the present invention, and FIG. 2 is a metal-made heat sink with the heat conducting spacer together with a heat-generating electronic component provided on a printed wiring board. It is a figure which shows the partial cross section of the state installed in the chassis.

The heat-conducting spacer 1 of this embodiment is formed by punching a synthetic resin sheet to form an electrically insulating sheet 2.
Silicone rubber heat conduction sheet 3 having a plurality of predetermined thicknesses and cross-sectional shapes on one surface thereof.
It is formed by adhering a, 3b, 3c and 3d in a predetermined arrangement. More specifically, for example, first, an adhesive material layer having a predetermined thin thickness is formed at a predetermined plurality of sites on the electrical insulating sheet 2 at a time by a method such as transfer or screen printing. After that, a predetermined heat conduction sheet 3a, 3b, 3c or 3 is formed on each adhesive material layer forming portion by using a jig.
It is manufactured by arranging d and then pressing and adhering. This heat conductive spacer is, for example, one metal plate portion 42 which is to be a heat sink of the metal chassis 4.
The printed wiring board to which the heat generating electronic components 7b, 7d, such as IC chips, etc., are attached after being temporarily fixed while holding a predetermined positional relationship on the side (illustrated schematically in FIG. 2). A locking card in which a widening pin is provided on both ends from the bottom side of the other metal plate portion 41 while maintaining a predetermined planar positional relationship with the other metal plate portion 41 of the metal chassis 4 described above. Spacers 51, 52 ...
While being inserted toward the mounting holes provided at predetermined positions of the other metal plate portion 41 and the printed wiring board 6, and snapped at the other end side of the locking card spacers 51, 52, .... The printed wiring board 6 is fixed to the metal plate portion 41 at a predetermined plane direction position and a predetermined height with almost one touch by pushing and stopping. At this time, the heat conducting spacer 1 is correctly and under a predetermined pressure interposed between the metal plate portion 42 of the chassis 4 forming the heat sink and the heat generating electronic components 7b, 7d ,. Heat conduction sheet 3
The surfaces of b, 3d ... Are in close contact with the heat-generating electronic components 7b, 7d, and the surface of the electrically insulating sheet 2 is in close contact with the heat sink 42. Therefore, the heat from the heat-generating electronic components 7b, 7d ... Can be sufficiently and satisfactorily transferred to the heat sink 42 side.

Next, FIG. 3 shows a heat conducting spacer according to a second embodiment of the present invention. Note that FIG. 3 is a partial cross-sectional view showing a state in which the heat conductive spacer according to the second embodiment of the present invention is interposed between the heat generating electronic component installed on the substrate and the heat sink. Further, since the parts denoted by the same reference numerals as those used in FIGS. 1 and 2 have the same functions, the description thereof will not be given.

The heat conducting spacer 10 of the second embodiment
Is different from the case of the heat conductive spacer 1 of the first embodiment,
How to attach the heat conduction sheets 30a to the electric insulation sheet 20 is different. That is, the heat conduction sheet 30
A step portion 31a having a step substantially equal to the thickness of the electrical insulation sheet 20 is formed at the peripheral edge portion on the one surface side of a ... A hole provided in the electrical insulation sheet 20 at this portion. It is installed by firmly fitting it into 21. The heat conducting spacer 10 is connected to the heat generating electronic component 7a ...
. And the heat sink 43 are interposed between the heat conducting sheets 30a ...

FIG. 4 shows another first modification of the electrically insulating sheet of the heat conducting spacer according to the above embodiment. In addition,
FIG. 4 is a diagram showing a partial cross section of the above other first modification. Another first modification 201 of the electric insulating sheet is that the electric insulating sheet portion which is the main body of the electric insulating sheet, here, the synthetic resin portion 202 is closely contacted with the surface of the synthetic resin portion 202 on the side in contact with the heat sink. A coating layer 203 is formed by a thin film technique of the formed metal. The metal coating layer 203 is used, for example, in contact with a separately provided heat sink so as to form a part of the heat sink, and makes the heat conduction from the heat conduction sheet more efficient to the heat sink.

FIG. 5 shows another second modification of the electrically insulating sheet of the heat conducting spacer according to the above embodiment. Note that FIG. 5 is a view showing a partial cross section of the second modification other than the above.
The other second modified example 204 of the electrical insulation sheet is that the hole 2 for ventilation is provided in a portion to which the heat conduction sheet is not attached.
05, 205, etc. are provided and cooperate with holes provided also in the corresponding part on the heat sink side to form ventilation holes to promote heat dissipation by convection. The electric insulating sheet 204 shows a case where a metal surface layer 206 which should form a heat sink or a part of the heat sink is provided on the surface on the side to be in contact with the heat sink.

FIG. 6 shows another third modification of the electrically insulating sheet of the heat conducting spacer according to the above embodiment. Note that FIG. 6 is a diagram showing a partial cross section of the third modification other than the above.
The above-mentioned third modified example 207 of the electrical insulating sheet has a tongue-shaped projection piece 20 formed by bending the tongue-shaped cut portion toward the side on which the heat sink is provided.
..., 208, and the like, which are elastically brought into contact with the heat sink through the tongue-shaped projections for use. At the portions of the tongue-shaped protrusions 208, 208, ..., The electrically insulating sheet is much stronger against the heat sink, and thus is more closely contacted with the heat sink, so that the heat is more effectively dissipated. The electric insulating sheet 207 has a metal surface layer 209 which is to be a part of the heat sink and is provided on the surface on the side to be in contact with the heat sink.

Next, FIG. 7 shows a heat conducting spacer according to a third embodiment of the present invention. FIG. 7 shows a heat conductive spacer of the present invention,
It is a figure showing a partial section in the state where it was inserted between a substrate and a heat sink. The main configuration of the third embodiment is the first
It is the same as the embodiment, and the portions denoted by the same reference numerals as those used in FIG. 2 and FIG.

The heat conducting spacer 11 of the third embodiment
Is different from the case of the heat conductive spacer 1 of the first embodiment,
How to attach the heat conduction sheets 13b, 13d ... To the substrate 6 is different. That is, the heat conduction sheets 13b, 1
3d ... are heat-generating electronic components 17 with respect to the substrate 6.
It is pressed against the substrate surface facing the side opposite to b, 17d. That is, the heat-conducting spacer 11 is correctly and under predetermined pressure applied on the metal plate portion 42 of the chassis 4 and the substrate surface of the substrate 6 which form a heat sink. The surfaces of the heat conduction sheets 13b, 13d, ... Of the heat conduction spacer 11 are in close contact with the surface of the substrate 6 opposite to the surface on which the heat-generating electronic components 17b, 17d are provided, while the sheet for electrical insulation is provided. The surface of the second surface opposite to the surface on which the heat conduction sheets 13b and 13d are provided is in close contact with the heat sink 42. As a result, the heat generated from the heat-generating electronic components 17b, 17d ... Is satisfactorily transferred to the heat sink 42 side via the substrate 6.

The third embodiment is particularly convenient when the heat-generating electronic components 17b, 17d, ... Are insert mounting type components. That is, when the lead wire extending from the component is a component that is soldered by protruding onto the surface of the substrate 6 on the side opposite to the heat-generating electronic components, the heat conduction to the solder or the like. The sheet for use may be closely attached to remove heat. By doing so, the thickness of each of the heat conduction sheets 13b, 13d, ... May be substantially equal to the distance between the metal plate portion 42 and the back surface of the substrate 6, and therefore the heat generating electronic component 17b. , 17d
..It is not necessary to consider the height of. Further, for this reason, the thickness of the heat conduction sheets 13b, 13d, ... Can be made thin, which leads to cost reduction of the heat conduction sheet. Furthermore, the heat conduction sheets 13b, 13d
.. does not need to be provided for each of the heat-generating electronic components 17b, 17d ..., and can be configured as an integrated thin sheet.

In this embodiment, the heat-generating electronic component of the insertion mounting type is described as being suitable, but it goes without saying that the heat-generating electronic component of the surface mounting type and other types may be used. However, in this case, the heat generated from the heat-generating electronic component is transmitted through the substrate, so that it is necessary to dispose the heat conduction sheet in the vicinity of the heat-generating electronic component.
Moreover, in FIG. 7, as a suitable example, the heat conduction sheet 13 is used.
b, 13d ... are heat-generating electronic components 17b, 17d ...
・ The figure shows the configuration that is placed just on the back side of, but it may be offset slightly. In addition, the heat-generating electronic component 17
b, 17d to the substrate 6 for heat conduction sheet 13a
Although it is provided on the opposite side to (the lower surface of the substrate 6 in FIG. 7), the same side (the upper surface of the substrate 6 in FIG. 7)
Of course, it may be provided in.

Although the embodiments of the present invention have been described above, the embodiments of the present invention are not limited to the above-described embodiments, and are within the technical scope of the present invention.
It goes without saying that it can be implemented in various modes. In the above embodiment, the electrically insulating sheet 2 is used as the supporting plate of the heat conductive spacer 11, but a supporting plate made of a conductive material may be used instead of the electrically insulating sheet.
Specifically, the electrically insulating sheet 2 in FIG. 2 or the electrically insulating sheet 20 in FIG. 3 may be formed of a sheet of a conductive material. In this way, the EMC effect can be obtained in addition to the thermal conductivity. In this case, the conductive material may be a metal material, or a material mixed with carbon, carbon fiber, metal particles or the like as a material for enhancing the EMC effect.

Further, the heat conducting sheet of the present invention is not only attached to the support plate and used as a part of the spacer as described above, but also used by being directly arranged on the heat sink itself. Good. That is, the heat conduction sheet may be directly attached to a position on the inner surface of the heat sink that faces the heat-generating electronic component on the printed circuit board or a position that faces the printed circuit board surface near the heat-generating electronic component. In this case, the heat generated from the heat-generating electronic component is directly transmitted to the heat sink via the heat conduction sheet.

[Brief description of drawings]

FIG. 1 is a perspective view of a heat conducting spacer according to a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing a state in which the heat conductive spacer is installed in a metal chassis forming a heat sink together with a heat-generating electronic component provided on a printed wiring board.

FIG. 3 is a partial cross-sectional view showing a state in which a heat conductive spacer according to a second embodiment of the invention is interposed between a heat generating electronic component installed on a substrate and a heat sink.

FIG. 4 is a diagram showing a partial cross section of another first modification of the electrically insulating sheet of the heat conductive spacer according to the present invention.

FIG. 5 is a view showing a partial cross section of another second modification of the electrically insulating sheet of the heat conductive spacer according to the present invention.

FIG. 6 is a diagram showing a partial cross section of another third modification of the electrically insulating sheet of the heat conductive spacer according to the present invention.

FIG. 7 is a partial cross-sectional view showing a state in which the heat conductive spacer according to the third embodiment of the present invention is installed in a metal chassis that forms a heat sink together with a heat-generating electronic component provided on a printed wiring board. .

[Explanation of symbols]

1, 10 ... Thermal conductive spacers 2, 20, 201, 204, 207 ... Electrical insulating sheets 3a, 3b, 3c, 3d, 13b, 13d ... Thermal conductive sheets 42, 43 ... Heat sink 6 ... Substrate, 7a, 7b, 7d, 17b, 17d ...
… Exothermic electronic components

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-7-111378 (JP, A) JP-A-9-55459 (JP, A) JP-A-8-83990 (JP, A) JP-A-8- 125383 (JP, A) JP 5-315777 (JP, A) JP 6-181395 (JP, A) JP 8-321696 (JP, A) Actually developed 63-33643 (JP, U) Japanese Patent Publication No. 47-30397 (JP, B1) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 23/36 H05K 7/20

Claims (2)

(57) [Claims] 1. A thermally conductive spacer is interposed between the one or substrate more heat-generating electronic component is installed and the heat sink, pre-order to close contact with the substrate surface of the heat-generating electronic components near A part where at least one heat conduction sheet having a predetermined shape and thickness is integrally attached to a predetermined position of the support plate, and the heat conduction sheet of the support plate is not attached
A heat-conducting spacer, characterized in that a hole is provided in the minute portion and the hole is used as a ventilation hole . 2. A thermally conductive spacer is interposed between the one or more heat generating electronic component and a heat sink disposed on the substrate, respectively in order to close predetermined for the heat-generating electronic component A plurality of heat conduction sheets having different shapes and thicknesses are integrally formed at predetermined positions on the support plate.
Mounting, a part of the supporting plate to which the heat conduction sheet is not mounted
A heat-conducting spacer, characterized in that a hole is provided in the minute portion and the hole is used as a ventilation hole .