JPH05315480A - Radiator - Google Patents

Abstract

PURPOSE:To enable a device (the title radiator) mounted with multiple high exothermic LSI elements, etc., to be in excellent contact with respective LSI elements, etc., thereby enabling the exotherm to be dissipated in high efficiency. CONSTITUTION:The title radiator is provided with a contact parts 16c made of an elastic material having excellent thermal conductivity in contact with LSI elements, multiple cut-off holes 16d through the parts around the contact parts 16c as well as holding parts 16f formed between the cut-off holes 16d as heat conductive flow paths simultaneously filling the role of springs absorbing the dispersion in the level of LSI elements.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiator such as an LSI device that generates a large amount of heat, and more particularly to a radiator that can maintain good contact for heat conduction by utilizing its spring property. is there.

[0002]

2. Description of the Related Art FIG. 10 is a sectional view showing a state where a conventional radiator is mounted on an LSI element. In the figure, 1 is LS
I element, 2 is a heat sink to which this LSI element 1 is attached via a high thermal conductive adhesive 3, 4 is a lead of this LSI element 1, 5 is silicon rubber, 6 is alumina to which the lead 4 of the LSI element 1 is adhered Ceramic substrate, such as 7
Is a bump and 8 is a welded portion.

In this structure, the TAB is formed on the ceramic substrate 6.
(Tape automated bonding) technology is used for face-down bonding, and the heat sink 2 is connected to the back surface with the same technology to make one module.
A large number of modules are mounted on this ceramic substrate 6, and L
The heat generated from the SI element 1 is radiated from the heat sink 2 provided on the back surface. In this way, the heat sink 2 is attached to each LSI element 1 to
It is possible to adjust that the height of the back surface of the element is slightly different.

FIG. 11 is a cross-sectional view showing a state in which another conventional radiator is mounted on an LSI element, particularly when the LSI element is mounted on a substrate by a flip chip method.
In the figure, 9 is a substrate, 10 is a polymer film, 11 is a thermally conductive liquid, and 12 is a heat sink.

In this structure, the heat conductive liquid 11 is attached to the heat sink 12 by the polymer film 10, and the heat conductive liquid 11 is inserted between the LSI element 1 and the heat sink 12.

As described above, the heat conductive liquid 11 is used to adjust that the height of the back surface of the LSI element 1 is slightly different due to the subtle undulations of the substrate 9 and the height of the bumps for element connection. ..

[0007]

However, in the radiator having the above structure, particularly the radiator shown in FIG. 10, it is necessary to attach a heat sink to each LSI element, and moreover, between the LSI element and its adjacent LSI element. Has
Since there is no heat sink, the cooling efficiency becomes worse. Further, the radiator shown in FIG. 11 has a structure in which the liquid is wrapped with a polymer film, which leads to an increase in the cost of the device, and the thermal conductivity of the polymer film, liquid, etc. is worse than that of metal, so a large heat radiation effect is obtained. There was a problem that I could not expect.

According to the present invention, in addition to the above-mentioned thermal connection between the heat sink and the heat-generating elements having variations in height, it is necessary to make a detailed correspondence for each heat-generating element, and the cooling efficiency or the cooling effect is poor. Moreover, in order to eliminate the problem of increasing the cost of the device, the purpose is to give elastic properties corresponding to each heating element by simply processing elastic material with good thermal conductivity. ..

[0009]

A radiator according to the present invention is
A plurality of contact portions respectively contacting a heating element such as an LSI element, and a plurality of holes formed around the contact portions,
A support portion formed between the holes is provided and is made of a material having good thermal conductivity.

[0010]

The present invention enables a highly efficient heat dissipation with a simple structure.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an LS of an embodiment of a radiator according to the present invention.
It is a cross-sectional side view which shows the state mounted | worn with I element. In the figure, 13 is an LSI element, 14 is a wiring board on which the LSI element 13 and the like are mounted, 15 is a bump for electrically connecting the LSI element 13 to the wiring board 14, and 16 is a detailed side view of the same. As shown in FIG.
Both ends 16a and 16b are fixed to the wiring board 14 and have a good heat conductivity and are made of an elastic material, and 17 is a thermal element for improving the thermal contact between the LSI element 13 and the radiator 16. Grease, 18 and 19
Is a radiation fin attached to the radiator 16.

In FIG. 2A and FIG. 2B, 16c is a contact portion with which the back surface of the LSI element 13 contacts,
16d is a hole having a plurality of widths h (see FIG. 3) formed in a V shape around the contact portion 16c, and 16e is a width g (see FIG. 3) provided at each corner of the contact portion 16c. hole,
16f is a width 1 formed between the punched holes 16d (see FIG. 3)
It is a square-shaped support part that serves as a flow path for transmitting heat and also acts as a spring, so that even if the contact part 16c moves up and down a little,
The vertical movement of the support portion 16f can be absorbed by the deformation of the support portion 16f. The width l of the support portion 16f
(See FIG. 3) shows good results when the distance is, for example, about 2 mm. 16g is a connecting portion formed between the contact portions 16c,
A step d is formed between the contact portion 16c and the connecting portion 16g.
(See FIG. 2A) is formed, and this step d is L
This is for absorbing the variation in height of the SI element 1, and 0.3 mm or less is sufficient as an example. In this case, the punched hole 16d is deformed so as to extend slightly from the original shape shown in FIG. 4A as shown in FIG. 4B.
This deformation can be absorbed by the elasticity of the spring.

With the radiator 16 formed in this way, L
The heat generated in the SI element 13 is applied to the contact portion 16 of the radiator 16.
c-Supporting portion 16f-Spreading entirely from the connecting portion 16g,
The heat is radiated and the heat can be radiated via the heat radiation fins 18 and 19.

As described above, the material of the radiator 16 is essentially elastic and excellent in heat conductivity, and is preferably a copper-based material such as phosphor bronze, but mainly aluminum. Metallic materials such as component materials are preferred. Also,
If the thickness of the radiator is too thin, the strength cannot be obtained. Conversely, if it is too thick, processing becomes difficult and heavy. Depending on the material used, a thickness of 0.3 mm or more is sufficient, and a thickness of 3 mm or less is easier to process. Also, radiator 1
The width h (see FIG. 3) of the punched hole 16d of No. 6 is about 1/2 of the thickness of the material, but it may be narrower or wider than that. Further, the width 1 of the supporting portion 16f serving as a heat flow path is set to be substantially the same as the material, but it is needless to say that it may be wider or narrower than this.

5 to 8 are plan views of essential parts showing other embodiments of the radiator, respectively.

Particularly, the radiator 20 shown in FIG.
By widening the pitch of 0a, the interval between the supporting portions 20b becomes wider, and the flow path for transmitting heat can be made wider.

The radiator 21 shown in FIG.
The support portion 21b is also N-shaped.

The radiator 22 shown in FIG. 7 is such that the support portion 22b is also linear by making the hole 22a linear. In this embodiment, during processing, it slightly rotates in the direction of the arrow. Further, the contact portion 22c also rotates in the arrow direction when pushed down.

The radiator 23 shown in FIG. 8 is formed by forming a hole 23a and a supporting portion 23b, which are located around the contact portion 23c, in one direction. Therefore, the contact portion 2
When 3c is pushed down, the area 23D surrounded by the dotted line contracts and the area 23E surrounded by the dotted line extends. In this way, when the region 23D contracts, the supporting portions 23b come into contact with each other, and serve as heat flow paths as they are. In this case, the contact part 2
When pushing down 3c, it is sufficient to bend it.

FIG. 9 shows a case where the radiator shown in FIG. 2 is applied to a flat pack type multi-chip module or the like. In the case of this embodiment, the radiator 16 is attached to the lid 24 of the flat pack, and the heat can be easily dissipated from the back surface of the element.

As described above, the radiator 16 is connected to the LS.
By being pressed against the I-chip 13, the contact portion 16c that comes into contact with the LSI element 13 is slightly pushed up along the back surface of the LSI element 13 and is fixed so as to be in close contact with the back surface of the LSI element 13.

Further, in the above description, the heat dissipation of the LSI element has been described, but the present invention is not limited to this, and it is needless to say that it can be used for transferring the heat of the heat generating portion to the case (housing).

Further, although the contact portion of the radiator is shown as a square, the shape is not limited to this, and it is needless to say that it may have a shape other than a circle. In addition, it goes without saying that the radiator may be provided with positioning processing for the LSI element.

Further, although the back surface of the LSI element is brought into contact with the connection portion of the radiator to radiate heat, the invention is not limited to this, and it goes without saying that it may be brought into contact with the diffusion surface.

Further, although the case where two contact portions of the radiator are formed in the lateral direction is shown, the present invention is not limited to this, and N contact portions are formed in the lateral direction.
Of course, the same can be done by forming N pieces in the vertical direction or N × M pieces in a matrix.

In this way, separate LSI elements can be easily connected in a state of low thermal resistance.

[0027]

As described in detail above, according to the radiator of the present invention, the heat generated from the mounted LSI element or the like can be easily dissipated with a simple structure. Moreover, since it is possible to make close contact with a large number of mounted LSI elements at the same time, there is an effect that heat can be easily and efficiently dissipated.

[Brief description of drawings]

FIG. 1 is a sectional side view showing a state in which an embodiment of a radiator according to the present invention is mounted on an LSI device.

2 is a side view and a plan view of the radiator shown in FIG. 1. FIG.

3 is a partially enlarged plan view of FIG. 2. FIG.

FIG. 4 is a view showing a modification of the punched hole in FIG.

FIG. 5 is a main part plan view showing another embodiment of the radiator according to the present invention.

FIG. 6 is a main part plan view showing still another embodiment of the radiator according to the present invention.

FIG. 7 is a plan view of an essential part showing still another embodiment of the radiator according to the present invention.

FIG. 8 is a main part plan view showing still another embodiment of the radiator according to the present invention.

FIG. 9 is a cross-sectional view showing a state in which an embodiment of a radiator according to the present invention is mounted on an LSI device.

FIG. 10 is a cross-sectional view of an LSI device equipped with a conventional radiator.

FIG. 11 is a cross-sectional view of an LSI device equipped with another conventional radiator.

[Explanation of symbols]

 16 Radiator 18, 19 Radiating fin 20-23 Radiator 24 Flat pack lid

Claims (2)

[Claims] 1. A plurality of contact portions, each of which is in contact with a heating element, a plurality of holes formed around the contact portions, and an indicator formed between the holes. A radiator characterized by being made of good material. 2. The radiator according to claim 1, wherein the radiator is made of a plate-shaped elastic material.