JP3313685B2 - Heat radiator for electronic components - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heat radiator for electronic parts.

[0002]

2. Description of the Related Art In recent years, it has become more and more important to rapidly cool an electronic component that generates heat, thereby preventing fluctuations in characteristics and malfunctions of the electronic component due to heat generation and improving reliability.

Also, electromagnetic waves radiated from electronic components are
It is also required to prevent adverse effects on the operation of other electronic components in the vicinity of the electronic component, and to prevent electromagnetic waves from leaking to the outside of the electronic device in which the electronic component is mounted and causing a failure. I have. In particular, electronic components such as ICs are not only required to have efficient heat dissipation measures because power consumption is increasing and heat generation is increasing due to the increase in the degree of integration and the speed of operation. Since the frequency of the radiated electromagnetic wave increases and external electronic components are easily affected by noise, a reliable noise countermeasure is required.

[0004]

As a heat radiator for an electronic component which achieves both the above-described heat radiation countermeasures and noise countermeasures, for example, a heat conductive sheet and a noise conductive sheet are arranged so that the heat conductive sheets are disposed on the uppermost layer and the lowermost layer. It is conceivable to alternately laminate the prevention sheets. Specifically, it is conceivable that a heat conductive sheet, a noise prevention sheet, and a heat conductive sheet are laminated in three layers in this order. However, since the sheets are easily peeled off only by stacking them, it is inconvenient to handle them as one component called a heat radiator for electronic components. Therefore, considering the convenience of handling as one part, it is preferable to integrate the sheets with a double-sided adhesive tape or the like.

However, when a heat radiator for electronic parts, in which each sheet is integrated with a double-sided adhesive tape or the like, is used in contact with the electronic parts, the thermal expansion coefficient differs between the heat conductive sheet and the noise prevention sheet. When the components are operated, they are heated by the heat generated, and when the components are stopped, they are naturally cooled (hereinafter referred to as heat history).

That is, when the heat conductive sheet has a higher coefficient of thermal expansion than the noise prevention sheet, the heat conductive sheet expands more than the noise prevention sheet when heated by the heat generated during operation of the electronic component. I do. At this time, since the heat conductive sheet and the noise prevention sheet are adhered to each other, the expansion of the heat conductive sheet is prevented by the noise prevention sheet. Therefore, there is a possibility that the heat history sheet may be cracked due to the heat history. When such a breach occurs, since the breach is an air layer, the thermal conductivity at that portion is low, and a sufficient heat radiation effect cannot be obtained.

On the other hand, if the electronic component is naturally cooled when the operation of the electronic component is stopped, the expanded heat conductive sheet shrinks more than the noise prevention sheet. At this time, since the heat conductive sheet and the noise prevention sheet are bonded, the heat conductive sheet tends to shrink the noise prevention sheet. Therefore, there is a possibility that wrinkles may be formed on the noise prevention sheet due to heat history. When such wrinkles occur, the internal crystals of the noise prevention sheet may be destroyed, and the electromagnetic wave cannot be sufficiently absorbed or shielded.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide a heat radiator for electronic parts which does not cause deterioration in characteristics due to a difference in thermal expansion between a heat conductive sheet and a noise prevention sheet. With the goal.

[0009]

Means for Solving the Problems and Effects of the Invention In order to solve the above-mentioned problems, the present invention is directed to alternately providing a heat conductive sheet and a noise prevention sheet such that the heat conductive sheets are arranged in the uppermost layer and the lowermost layer. A heat radiator for electronic components laminated on
It has a bonding portion in which a pair of heat conductive sheets sandwiching the noise prevention sheet are bonded without passing through the noise prevention sheet, and the noise prevention sheet and the pair of heat conductive sheets are not bonded.

In this heat radiator for electronic parts, the noise prevention sheet and the pair of heat conduction sheets sandwiching the noise prevention sheet are not adhered to each other. Is glued. For this reason, the heat conductive sheet and the noise prevention sheet can expand and contract independently of each other, and even if the thermal conductive sheet and the noise prevention sheet have different coefficients of thermal expansion, the expansion and contraction of the other sheet is limited by one sheet. It will not be done. In addition, since each sheet is integrated by an adhesive portion, convenience in handling as one component is ensured.

Here, the heat conductive sheet is not particularly limited as long as it is a sheet having a high heat conductivity. However, a sheet obtained by blending a heat conductive filler called a filler in a resin base material is preferable. As the filler, for example, aluminum oxide,
Ceramic powders such as boron nitride, aluminum nitride, zinc oxide, silicon carbide, derivatives such as barium titanate, ferrite, Fe-Si, Fe-Si-Al, Fe-N
i, powders of magnetic materials such as Fe-Cr, Fe-based nanocrystalline metals, Co-based alloys, hydrates of metal compounds such as aluminum hydroxide, magnesium hydroxide, zinc hydroxide, calcium hydroxide, tin hydroxide, etc. Is mentioned. Examples of the resin base material include silicone rubber, elastomer, and synthetic resin (EPDM, butyl rubber, chloroprene rubber, acrylic rubber, nitrile rubber, fluorine rubber, chlorosulfonated polyethylene rubber, styrene-butadiene rubber, chlorinated polyethylene, and the like). No. The noise prevention sheet is not particularly limited as long as it is a sheet capable of suppressing noise such as an electromagnetic wave absorbing material or an electromagnetic wave shielding material. For example, examples of the electromagnetic wave absorbing material include Fe-Si and Fe-Si.
Examples include magnetic material foils such as Si-Al, Fe-Ni, Fe-Cr, Fe-based nanocrystalline metals, and Co-based amorphous materials. Examples of the electromagnetic wave shielding material include conductive material foils such as copper, aluminum, and iron. . The electromagnetic wave absorbing material attenuates the electromagnetic wave by absorbing the magnetic field component of the electromagnetic wave, and the electromagnetic wave shielding material reflects the electromagnetic wave by reflecting the electric field component of the electromagnetic wave.

As described above, according to the heat radiator for electronic parts of the present invention, even if the heat history is added, the characteristic deterioration due to the difference in thermal expansion between the heat conductive sheet and the noise prevention sheet does not occur. Therefore, when the heat radiator for an electronic component of the present invention is used in contact with an electronic component such as an IC, an LSI, or a CPU, an effect of stably exerting a heat radiating action and a noise removing action over a long period is obtained.

[0013] The electronic component heat radiator of the present invention, that the heat conduction flow agent is not thermally conductive fluidized layer is formed by being filled between the noise prevention sheet and a pair of heat conductive sheets sandwiching the. In the present invention, since the heat conductive sheet and the noise prevention sheet are not bonded by a double-sided adhesive tape or the like, a gap, that is, an air layer may be formed between the heat conductive sheet and the noise prevention sheet. Since this air layer has low thermal conductivity, a sufficient heat radiation effect cannot be obtained. Therefore, by filling a heat conducting fluid between the heat conducting sheet and the noise prevention sheet, the heat conduction sheet and the noise prevention sheet maintain a state in which they can expand and contract independently of each other, and such an air layer Is formed so as not to reduce the thermal conductivity.

The heat-conducting fluidizer is not particularly limited as long as it is a viscous fluid having heat conductivity. For example, the heat-conducting grease or phase change material (sheet-like (solid) at room temperature, (A material that becomes a gel or a liquid when the temperature at which the electronic component is operated (about 40 ° C.)).
Examples of the thermally conductive grease include, for example, silicone grease containing the above-mentioned filler. Examples of the phase change material include olefin-based elastomers, paraffin-based elastomers, and ethylene-based elastomers. Specifically, ethylene-vinyl acetate copolymer (EV
A) and an ethylene / propylene copolymer polymer (tolylene).

[0015] Then, the thermally conductive sheet <br/> over preparative constituting the uppermost layer and the lowermost layer, it is preferable that the plurality of communication holes communicating to thermally conductive fluidized layer is formed. In this case, when the electronic component radiator is used sandwiched between the electronic component and the heat sink, the heat conductive fluid is pressed by the electronic component and the heat sink, and the heat conductive fluid is passed through the communication hole from the heat conductive fluid layer to the uppermost layer and the uppermost layer. It seeps to the surface of the lower layer. In order to improve the contact property between the heat radiator for electronic components and the electronic component and the contact property between the heat radiator for electronic components and the heat sink,
The thermal conductivity is increased, and the electronic components can radiate heat very efficiently.

In the heat radiator for electronic parts of the present invention, the adhesive portion may be formed to be elongated along at least one edge of a pair of heat conductive sheets sandwiching the noise prevention sheet. For example, if the adhesive portion is elongated along only one edge of the heat-conducting sheet or if it is elongated along two opposing edges, the direction of the edge during manufacturing is It is preferable because it can be continuously extruded and molded. In the latter case, it is more preferable because the sheets are surely integrated. Alternatively, the bond may be along three edges.
The pair of heat conductive sheets is formed by forming
Shape . In this case, it is difficult to continuously extrude and form the sheet in the edge direction at the time of manufacturing, but the sheets are more reliably integrated. Note that the bonding portion may be formed over the entire circumference of the heat conductive sheet.

[0017] The bonding portion may be formed in a spot shape along at least one edge of a pair of heat conductive sheets sandwiching the noise prevention sheet. For example, when the bonding portion is formed in a spot shape along only one edge of the heat conductive sheet or in a spot shape along two opposing edges, It is preferable because it can be extruded and molded continuously in the edge direction, and in the latter case, it is more preferable because each sheet is surely integrated. Alternatively, the bonding portion may be formed such that a pair of heat conductive sheets sandwiching the noise prevention sheet are formed in a bag shape.

In the case where the adhesive portion is formed in a spot shape as described above, the noise prevention sheet and a pair of heat conductive sheets sandwiching the noise prevention sheet are formed in substantially the same size, and are formed in a spot shape along the edge of the noise prevention sheet. A through hole or a notch may be formed, and the two heat conductive sheets may be bonded through the through hole or the notch (that is, the bonding portion is formed in the through hole or the notch). By doing so, the noise prevention sheet can secure a wide area equivalent to that of the heat conductive sheet, so that it has a high effect of absorbing or shielding electromagnetic waves, which is advantageous for noise suppression.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First Example] FIG. 1 is an explanatory view of the first embodiment of the present invention, (a) is a plan view, (b) a sectional view taken along A-A. The heat radiator 10 for an electronic component includes a first heat conductive sheet 11 formed of the uppermost layer formed of silicone rubber mixed with a filler, and a second heat conductive sheet 12 formed of the same material as the lowermost layer.
And a noise prevention sheet 13 made of a permalloy foil (Fe—Ni alloy foil) sandwiched between the heat conductive sheets 11 and 12. That is, the heat radiator 10 for an electronic component includes the first heat conductive sheet 11, the noise prevention sheet 13, and the second heat conductive sheet 11.
The heat conductive sheets 12 are laminated in this order.
The heat radiator 10 for an electronic component has a substantially square shape when viewed from above, and the noise prevention sheet 13 includes both heat conductive sheets 11 and
12 is formed to be shorter in width than the bonding portions 14 described later.

The heat radiator 10 for electronic parts has bonding portions 14, 14 for bonding the heat conductive sheets 11, 12 without the noise prevention sheet 13 therebetween, and the heat conductive sheets 11, 12.
Are formed to be elongated along the edge of the. This bonded part 1
Reference numerals 4 and 14 are formed at opposing edges. And
The first heat conductive sheet 11 and the noise prevention sheet 13 are not bonded, and the second heat conductive sheet 12 and the noise prevention sheet 13 are not bonded. Noise prevention sheet 13
May be formed so as to be smaller than the width of the slit 15 formed by the heat conductive sheets 11 and 12 (the length in the left-right direction in FIG. 1B).

Next, a method of manufacturing the heat radiator 10 for an electronic component will be described. In order to manufacture the heat radiator 10 for electronic components,
For example, the noise prevention sheet 13 may be placed on the second heat conductive sheet 12, and an uncured heat conductive resin may be applied thereon and then sufficiently cured. After the uncured heat conductive resin is cured, the adhesive portions 14 and 1 are formed along opposing edges.
4 is formed and the first heat conductive sheet 1 forming the uppermost layer
1 is formed, but the pair of heat conductive sheets 11 and 12 and the noise prevention sheet 13 remain unbonded.

As another manufacturing example, the second heat conductive sheet 12
The noise prevention sheet 13 may be placed on the first heat conduction sheet 11, a heat conductive adhesive may be applied to both left and right sides of the noise prevention sheet 13, and the first heat conduction sheet 11 may be placed thereon. Next, a usage example of the electronic component heat radiator 10 will be described with reference to FIG. FIG. 2 is a diagram illustrating the use of the first reference example . In this usage example, the heat radiator 10 for electronic components is disposed between an electronic component 17 such as an IC and a heat sink 18. That is, the upper surface of the electronic component 17 that generates heat is substantially flat, and the lower portion of the electronic component 17 is disposed on the wiring board 19. The heat sink 18 is formed of a material having a small specific heat (aluminum, copper, or the like), and has a radiation fin 18a formed thereon. The electronic component radiator 10 is sandwiched between the substantially flat lower surface of the heat sink 18 and the substantially flat upper surface of the electronic component 17.

Note that the “upper surface” of the electronic component 17 refers to a surface opposite to the surface on which the electronic component 17 is mounted on the wiring board 19. Therefore, when the electronic component 17 is mounted on the back surface of the horizontal wiring board 19, the “upper surface” of the electronic component faces downward.

In the example of use of FIG. 2, heat is generated when the electronic component 17 is operating. This heat is applied to the second heat conductive sheet 12 of the heat radiator 10 for the electronic component → the bonding portion 14,
14 → first heat conductive sheet 11 or second heat conductive sheet 12 → noise prevention sheet 13 → first heat conductive sheet 1
The heat is transmitted to the heat sink 18 through the path 1 and is quickly released from the heat sink 18 to the outside. As described above, since the electronic component 17 is quickly cooled, the electronic component 17 does not become hot due to heat generation, and the characteristics do not fluctuate or malfunction, so that the reliability of operation can be improved.

When the electronic component 17 is operating, an electromagnetic wave is emitted from the electronic component 17. This electromagnetic wave is prevented from leaking outside by the noise prevention sheet 13 of the heat radiator 10 for electronic components. Here, since the noise prevention sheet 13 is a permalloy foil (a foil of a magnetic material), the electromagnetic wave is shielded by absorbing the magnetic field component of the electromagnetic wave to prevent the electromagnetic wave from leaking to the outside. As described above, since the leakage of the electromagnetic wave is prevented,
Is reliably prevented from picking up noise caused by this electromagnetic wave.

By the way, when the operation and the stop of the operation of the electronic component 17 are repeated, the heat radiator 10 for the electronic component receives a heat history due to the repetition of being heated when the operation of the electronic component 17 is operated and being naturally cooled when the operation is stopped. Here, since the silicone rubber, which is the base material of the first and second heat conductive sheets 11 and 12, has a higher coefficient of thermal expansion than the permalloy (Fe—Ni alloy) that forms the noise prevention sheet 13, the electronic component 17 has a higher thermal expansion coefficient. When heated during operation, the first and second heat conductive sheets 11 and 12 expand more than the noise prevention sheet 13. On the other hand, when the electronic component 17 is naturally cooled when the operation is stopped, the expanded heat conductive sheets 11 and 12 contract more greatly than the noise prevention sheet 13. However, since the noise prevention sheet 13 and each of the heat conductive sheets 11 and 12 are not adhered, each of the heat conductive sheets 11 and 12 is not bonded.
Expands and contracts independently without being restricted by the noise prevention sheet 13. Therefore, both heat conductive sheets 1
Since the noise prevention sheet 13 does not hinder the expansion of the heat conductive sheets 1 and 12 when the heat conductive sheets 1 and 12 are expanded.
No cracks occur in 1,12. In addition, when the two heat conductive sheets 11 and 12 contract, the noise prevention sheet 13 is used.
Noise prevention sheet 1 because it does not forcibly shrink
No wrinkles are formed on 3.

As described above, according to the electronic component radiator 10, even if the heat history is added, the heat conductive sheet 11,
The characteristics do not deteriorate due to the difference in thermal expansion between the noise prevention sheet 12 and the noise prevention sheet 13. Therefore, when the electronic component radiator 10 is used in contact with the electronic component 17 such as an IC, an LSI, and a CPU, an effect of stably exerting a heat radiating action and a noise removing action over a long period is obtained.

The heat radiator 10 for an electronic component can be continuously extruded and molded in the direction of its edge during manufacturing, so that it is not only suitable for mass production, but also the bonding portions 14 and 14 along the opposing edges. 14 are formed, each sheet 11-
13 are surely integrated.

[ First Embodiment] FIG. 3 is an explanatory view of the present embodiment, in which (a) is a plan view,
(B) is BB sectional drawing. This heat radiator 2 for electronic parts
0 indicates that the heat conductive fluidized layer 21 is formed between the pair of heat conductive sheets 11 and 12 and the noise prevention sheet 13 by being filled with heat conductive silicone grease as a heat conductive fluidizing agent. Except for the above-mentioned heat radiator for electronic components 1
The configuration is the same as that of 0. Therefore, the same components as those of the above-described heat radiator 10 for electronic components are denoted by the same reference numerals, and description thereof will be omitted. In addition, as can be seen from FIG.
It can be said that the heat conductive fluid is filled in the slit 15 between the first heat conductive sheet 11 and the second heat conductive sheet 12.

Next, in order to manufacture the heat radiator 20 for electronic parts, for example, heat conductive silicone grease is applied to both surfaces of the noise prevention sheet 13, and this is placed on the second heat conductive sheet 12. The first heat conductive sheet 11 is placed from above, and the bonding portions 14 and 14 may be formed by welding or bonding elongated along the opposing edges. Alternatively, after manufacturing the above-described electronic component heat radiator 10, the first
The heat conductive silicone grease may be filled between the heat conductive sheet 11 and the noise prevention sheet 13 and between the second heat conductive sheet 12 and the noise prevention sheet 13.

Next, an example of use of the electronic component radiator 20 will be described with reference to FIG. FIG. 4 is an explanatory diagram of use of the present embodiment. The electronic component radiator 20 of the present embodiment includes:
It is used in the same manner as the electronic component heat radiator 10 (see FIGS. 1 and 2). By the way, in the electronic component heat radiator 10 described above, since the sheets 11 to 13 are not bonded, between the first heat conductive sheet 11 and the noise prevention sheet 13 and between the second heat conductive sheet 12 and the noise prevention sheet 13
There is a possibility that a gap, that is, an air layer may be formed between them.
When such an air layer is formed, the air has a low thermal conductivity, so that a sufficient heat radiation effect cannot be obtained. For this reason, in this embodiment, by providing the heat conduction fluidized layer 21 between the pair of heat conduction sheets 11, 12 and the noise prevention sheet 13, the noise prevention sheet 13 and each heat conduction sheet 11,
12, while maintaining a state in which they can expand and contract independently of each other, and preventing the formation of the above-mentioned air layer so as not to cause a decrease in thermal conductivity.

As described above, according to the electronic component radiator 20 of the present embodiment, the same effects as those of the above-described electronic component radiator 10 can be obtained, and the noise prevention sheet 13 and the pair of heat conductive sheets 11 and 12 can be obtained. Therefore, a sufficient heat radiation effect can be obtained for a long period of time since no air layer is formed between the first and second air layers.

[ Second Embodiment] FIG. 5 is a sectional view of the present embodiment. FIG. 5 shows only the left half, but the right half appears symmetrically with the left half. The electronic component radiator 30 includes a plurality of first heat conductive fluid layers 21 that communicate with the surface of the first heat conductive sheet 11 to the heat conductive fluidized layer 21.
Are formed, and the second heat conductive sheet 1 is formed.
The second plurality communicating with the heat transfer fluidized bed 21 also on the surface of the second
Except that communication holes 32, 32,... Are formed, the configuration is the same as that of the electronic component heat radiator 20 described above. For this reason, the same components as those of the above-described electronic component heat radiator 20 are denoted by the same reference numerals, and description thereof will be omitted. Also, the manufacturing example may be manufactured according to the electronic component heat radiator 20 described above.

Next, the heat radiator 30 for the electronic component of the present embodiment will be described.
An example of using will be described with reference to FIG. FIG. 6 also shows only the left half, but the right half appears symmetrically with the left half. The electronic component radiator 30 of the present embodiment includes:
The electronic component radiator 3 is used in substantially the same manner as the electronic component radiator 20 (see FIG. 4), but as shown in FIG.
When the electronic component 17 is used by being sandwiched between the electronic component 17 and the heat sink 18, the electronic component 17 and the heat sink 18 press the first communication hole 31, 31, 31.
Because the heat transfer fluid oozes out to the surface of the top layer via ...
The first heat conductive sheet 11 and the heat sink 18 come into contact with each other via the heat conductive fluid. Similarly, since the heat-conducting fluid flows out from the heat-conducting fluidized bed 21 through the second communication holes 32, 32, ... to the surface of the lowermost layer, the second heat-conducting sheet 1
2 and the electronic component 17 also come into contact with each other via the heat conducting fluid. As a result, due to the presence of the heat conducting fluid, the contact property between the electronic component radiator 30 and the electronic component 17 and the contact property between the electronic component radiator 30 and the heat sink 18 are improved.

As described above, according to the electronic component radiator 30 of the present embodiment, the same effects as those of the above-described electronic component radiator 20 can be obtained, and in addition, the first communication holes 31, 31,.
And the heat conductive fluid that has oozed out of the heat conductive fluid layer 21 through the second communication holes 32, 32, 32,.
In order to improve the contact between the electronic component 17 and the electronic component radiator 30 and the heat sink 18, the thermal conductivity is increased, and the electronic component 17 is extremely efficiently radiated.

[ Second Reference Example ] FIGS. 7A and 7B are explanatory views of a second reference example of the present invention . FIG. 7A is a plan view, and FIG. The electronic component radiator 40 includes a first thermal conductive sheet 41 formed of the uppermost layer formed of silicone rubber mixed with a filler, and a second thermal conductive sheet 42 formed of the same material as the lowermost layer.
And a noise prevention sheet 43 made of permalloy foil sandwiched between the heat conductive sheets 41 and 42. That is,
The heat radiator 40 for an electronic component includes a first heat conductive sheet 41.
The noise prevention sheet 43 and the second heat conductive sheet 42 are laminated in this order. The electronic component radiator 40 has a substantially square shape when viewed from above. The noise prevention sheet 43 is formed in the same size as the pair of heat conductive sheets 41, 42, and has a plurality of through holes 43a, 43a,.

The electronic component radiator 40 has a bonding portion 4
Are formed in the form of spots along the right and left edges of the pair of heat conductive sheets 41,. The bonding portions 44, 44,...
3a, 43a,... And a pair of heat conductive sheets 41, 42
Are adhered to each other without interposing the noise prevention sheet 43. Then, the first heat conductive sheet 41 and the noise prevention sheet 43 are not bonded, and the second heat conductive sheet 42 and the noise prevention sheet 43 are not bonded.

Next, manufacturing examples and usage examples of the electronic component heat radiator 40 are substantially the same as those in the first reference example, and thus description thereof will be omitted. According to the electronic component heat radiator 40, similarly to the first reference example , when the electronic component heat radiator 40 is used in contact with the electronic component 17, the heat radiator 40 has a long-term stable heat radiating effect and a noise removing effect. Is obtained. In addition, the heat radiator 40 for electronic components
Is suitable for mass production because it can be continuously extruded and molded in the direction of its edge during manufacturing, and each sheet is formed because the adhesive portions 44 are formed along opposing edges. 41 to 43 are surely integrated. Further, since the noise prevention sheet 43 is larger than in the first reference example , it is easier to remove noise.

[Other Embodiments] The embodiments of the present invention are not limited to the above-described embodiments, and it goes without saying that various embodiments can be adopted as long as they fall within the technical scope of the present invention. . For example, in each usage drawing, the heat generated from the electronic component 17 is released to the heat sink 18, but the upper surface of the electronic component radiator 10, 20, 30, 40 contacts the housing instead of contacting the heat sink 18. The heat generated from the electronic component 17 may be released to the housing.

In the first and second embodiments, the adhesive portions 14 are formed along the opposing edges of the pair of heat conductive sheets 11 and 12. Alternatively, for example, FIG.
The bonding portion 14 may be formed on only one side as shown in FIG. 8A, or the bonding portion 14 may be formed along three edges as shown in FIG. 1
You may make it 1 and 12 become a bag shape. Both are first
Almost the same effects as those of the second embodiment can be obtained. However, in the case of FIG. 8A, since the bonding portion 14 is formed on only one side, the horizontal width of the noise prevention sheet 13 is wider than when the bonding portion 14 is formed on both sides. Therefore, there is a merit that noise can be easily removed. On the other hand, in the case of FIG. 8B, although it is difficult to continuously extrude and form the sheet in the edge direction at the time of manufacturing, there is an advantage that the sheets are more reliably integrated. Further, as shown in FIG. 8C, the bonding portion 14 may be formed over the entire circumference.

[0041] With regard to the second reference example, it may be provided with a thermally conductive fluid layer 21 as in the first embodiment, in which case the same effects as the first embodiment is obtained. Further, the heat transfer fluidized bed 21 is provided as in the second embodiment, and the first communication holes 3 are formed.
, And the second communication holes 32, 32, ..., in which case the same effects as in the second embodiment can be obtained.

Similarly, in the second reference example , the heat conduction fluidized bed 2
1, the spot-shaped bonding portion 44 may be formed only on one side, the bonding portion 44 may be formed along three edges, or the bonding portion 44 may be formed over the entire circumference. Good. The shape of the spot is not particularly limited to a circle, but may be a polygon such as a quadrangle. Further, as shown in FIG.
b, 43b,... are provided, and the notches 43b, 43b,.
A spot-shaped bonding portion 44 may be provided in the inside.

Further, in each embodiment, a configuration in which the first embodiment is arranged in the horizontal direction (for example, FIG. 10A shows a configuration in which the first embodiment is arranged in the horizontal direction) may be adopted, or a configuration in which the first embodiment is stacked in the vertical direction. (For example, FIG. 10B is a vertical stack of the second embodiment). In FIG. 10B, the noise prevention sheets 13 and 13 may be different from each other. For example, if one is a foil of a magnetic material and the other is a foil of a conductive material, the foil of the magnetic material absorbs a magnetic component of an electromagnetic wave. In this way, the generation of noise is prevented, and the conductive material foil prevents the generation of noise by reflecting the electric field component of the electromagnetic wave. Becomes possible.
Alternatively, noises in a wider range may be removed by using magnetic material foils having different frequency bands to be absorbed.

Furthermore, the noise prevention sheet 1 of each embodiment
3, 43 may be formed by laminating a plurality of foils. Also in this case, the noise may be removed more reliably by laminating the magnetic material foil and the conductive material foil, or by laminating two or more magnetic material foils having different absorption frequency bands. Wide-area noise may be removed.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory diagrams of a first reference example , in which FIG. 1A is a plan view and FIG.

FIG. 2 is an explanatory diagram of use of the first reference example .

FIGS. 3A and 3B are explanatory diagrams of the first embodiment, in which FIG. 3A is a plan view and FIG. 3B is a sectional view taken along line BB.

FIG. 4 is an explanatory diagram of use of the first embodiment.

FIG. 5 is a cross-sectional view (only the left half is shown) of the second embodiment.

FIG. 6 is an explanatory view of use of the second embodiment (only the left half is shown).

FIGS. 7A and 7B are explanatory diagrams of a second reference example , where FIG. 7A is a plan view and FIG. 7B is a cross-sectional view taken along line DD.

FIG. 8 is an explanatory diagram of another embodiment.

FIG. 9 is an explanatory diagram of another embodiment.

FIG. 10 is an explanatory diagram of another embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Heat radiator for electronic components, 11 ... 1st heat conductive sheet, 12 ... 2nd heat conductive sheet, 13 ... Noise prevention sheet, 14 ... Adhesive part, 15 ... Slit ,
17 ... electronic parts, 18 ... heat sink, 18a
... heat radiation fins, 19 ... wiring board, 20 ... heat radiator for electronic parts, 21 ... heat conduction fluidized bed, 30 ...
Heat radiator for electronic parts, 31 ... 1st communication hole, 32 ...
2nd communication hole, 40 ... heat radiator for electronic parts, 41 ...
First heat conductive sheet, 42... Second heat conductive sheet, 43
... noise prevention sheet, 43a ... through-hole, 44
..Adhesive parts.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-10-294580 (JP, A) JP-B 5-74457 (JP, B2) Patent 3068613 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05K 7/20

Claims (6)

(57) [Claims] 1. A as the top layer and the thermally conductive sheet in the lowest layer are arranged, an electronic component for heat radiation formed by laminating alternately with said heat conducting sheet and noise prevention sheet, sandwiching the noise prevention sheet The noise prevention sheet and the pair of heat conduction sheets are not adhered to each other, and have a bonding portion in which the pair of heat conduction sheets are adhered without passing through the noise prevention sheet. And a heat conducting fluidizing layer formed by filling a heat conducting fluid between them. Wherein the the thermally conductive sheet forming the top and bottom layers, the heat dissipation for electronic components according to claim 1, wherein a plurality of communicating holes communicating to the heat conducting fluidized layer is formed body. Wherein the adhesive portion is an electronic component for heat radiation member according to claim 1 or 2, characterized in that it is elongated formed along at least one edge of said pair of heat conductive sheet. 4. The heat radiator for an electronic component according to claim 3 , wherein the adhesive portion is formed to be elongated along two opposing edges of the pair of heat conductive sheets. 5. The electronic component heat radiator according to claim 1 or 2, characterized in that said pair of heat conductive sheet by forming along the bonding portion into three edge is like a bag . Wherein said adhesive portion is an electronic component for heat radiation member according to claim 1 or 2, characterized in that it is formed into a spot shape along at least one edge of said pair of heat conductive sheet .