JPH027550A - Radiator for electronic device - Google Patents

Abstract

PURPOSE:To enhance heat-dissipating performance and enable line diameter and arrangement density to be modified easily by providing a corrugate-shaped pin fin consisting of a plurality of line-shaped heat conductors where fins are placed in parallel with some gap between them and are placed being curved in corrugate shape. CONSTITUTION:A radiator 7 is engaged to a stub 1 and is functioned as a radiator. In the radiator 7, a plurality of line-shaped heat conductors 10 are arranged in parallel with some gap between them on a radiator surface 9 of a fin supporting member 8 which serves as a member for mediating heat from an electronic device, a plurality of line-shaped heat conductors 10 are curved in corrugate shape, and a curved top part 11 is sealed to the heat-radiating surface of the fin supporting member 8. A pure meal thin wire such as silver, copper and aluminum or an alloy thin wire, or a metal thin wire where solder plating, tin plating, etc., are provided to the metal thin wire are used as a wire-shaped heat conductor.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat sink for electronic equipment. For more details,
This invention relates to a heatsink for electronic equipment with a pin fin that has good heat dissipation performance.

[Prior Art and Problems to be Solved by the Invention] In electronic equipment, when a semiconductor element or the like is energized, heat is generated due to its electrical resistance. In general, when the temperature rises, semiconductors malfunction or break down in a short period of time, so it is necessary to quickly dissipate the heat generated by the components. For this reason, heat dissipation fins are usually attached to the semiconductor itself or the substrate on which the semiconductor is attached.

Conventional fins are plate-shaped, and in order to expand the heat radiation area, the plate is processed into a U-shape, plate shape, plate shape, or corrugated shape and attached to the heat radiation surface. In the case of such plate-shaped fins, mounting is difficult in manufacturing to dramatically expand the heat dissipation area of the fin relative to the heat dissipation surface, and a thick boundary layer occurs on the plate surface, and this boundary layer Since it accumulates on the surface and forms a heat insulating layer, there are problems such as high heat exchange efficiency cannot be obtained. From that point of view, pin-shaped fins are preferable.
By increasing the density of attaching the bottle-shaped fins to the surface of the equipment, it is possible to expand the heat radiation area and further increase the heat exchange efficiency.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a new heat radiator for electronic equipment that increases the heat radiation area of the fins and provides high heat radiation performance.

[Means to solve the problem]

An object of the present invention is to provide a fin comprising a fin and a fin support member that supports the fin and mediates heat conduction with an electronic device, the fins being arranged parallel to each other at intervals and curved in a corrugated manner. This is achieved by a heat sink for electronic equipment with corrugated pin fins, which is characterized by being composed of a plurality of linear heat conductors.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A heat sink for electronic equipment according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a sectional view showing an embodiment of a corrugated pin-fin radiator according to the present invention. As shown in the figure,
Stud 1 made of copper, aluminum, etc. with good thermal conductivity
is brazed to the ceramic case 2 in advance, the half-quad element 4 is fixed in the recess 3 of the case 2, and the electrodes of the semi-quad element 4 are connected with thin metal wires 5 mainly made of aluminum, gold, etc. (not shown) and a pad (not shown) on the case 2 side, and after sealing the recess 3 with the cap 6, the heat radiator 7 according to the present invention is fitted to the stand l, and functions as a heat radiator. let

In the heat sink 7 according to the present invention, the heat radiation surface 9 of the fin support member 8 serves as a member that mediates heat conduction with electronic equipment.
A plurality of linear thermal conductors IO are arranged parallel to each other at intervals, and the plurality of linear thermal conductors 10 are curved in a corrugated shape, and the curved top portion 11 is the heat dissipation surface of the fin support member 8. It is fixed to 9.

The linear thermal conductor used in the present invention is a pure metal thin wire such as silver, copper, or aluminum, or an alloy thin wire, or
It is possible to use a thin metal wire obtained by subjecting the thin metal wire to solder plating, tin plating, or the like.

There is no particular limitation on the cross-sectional shape of the linear thermal conductor, but
When used as a heatsink fin, it reduces pressure loss and
In addition, in order to increase heat exchange efficiency, it is preferable to use a linear heat conductor with a nearly circular cross section. The thermal conductivity of the linear thermal conductor is preferably 0.40 Caf/am·sec·°C or higher, and depending on the application, a linear thermal conductor having a more appropriate thermal conductivity can be selected and used.

In order to expand the heat dissipation area of the fin of the present invention and obtain high heat dissipation performance, the size of the linear thermal conductor used and the arrangement density of the corrugated pin fins may be set within the following specific ranges.

0.25≦X≦2.5 0.25≦XY≦2.5 Here, X is the outer circumference length (dragon) of the cross section of the linear thermal conductor, and Y is the arrangement density of the linear thermal conductor. As shown in Fig. 2, for a cotton-like heat conductor transformed into a corrugated shape, the arrangement pitch Y of coils (corrugated state) of the same linear body, (hon/dragon) and the adjacent linear body are array pitch Y2 (
The arithmetic average Y is 0.1 pieces/dragon~10 pieces/m1・Y2 is 0.1 pieces/
It may be appropriately selected within the range of mm to 10 pieces/seal.

If X<0.25, the wire diameter of the linear thermal conductor is too small and its mechanical properties are too low, making it extremely difficult to handle when manufacturing the radiator and reducing production efficiency. Undesirable.

When X>2.5, the wire diameter of the linear thermal conductor is too large, making it difficult to exhibit the performance as a bottle-shaped fin. A more preferable range of X is 0.5≦X≦2.0, and in the case of a linear thermal conductor with a circular cross section, approximately
corresponds to

On the other hand, when XY<0.25, the heat radiation area of the linear thermal conductor for pin-shaped fins is too small and high heat radiation performance cannot be obtained.

When X Y > 2.5, the heat dissipation area increases, but the distance between the fins becomes too narrow, and the pressure loss of the cooling fluid becomes too large. A more preferable range of xy is 0.35≦XY≦1.2, and the wire diameter of circular cross section is 10
In the case of a linear thermal conductor with a diameter of 0, the arrangement density of the linear thermal conductor is equivalent to 1.11 pieces/2 to 3.82 square meters.

Next, an example of a method for manufacturing a heat sink according to the present invention will be described with reference to FIGS. 3 to 6.

As shown in FIG. 3, a plurality of linear thermal conductors 10 are wound into a puff cage shape (not shown), and are set in a required number on a reel 13, and are moved by a pair of heating press rolls 21 and 21', which will be described later. drawn out. At that time, the plurality of linear thermal conductors 10 are pulled out through the battens 14 and the forelimbs 15 and then through the tension bars 16, so that the tension is made uniform, and then the grooved guide rollers 17
And through the reed 18, they are arranged in substantially equal pinches within one plane. On the other hand, the sheet 12 made of soluble resin is pulled out from the sheet roll 12', and the guide roll 19,
20, it is guided together with the group of linear heat conductors 10 to a pair of heated press rolls 21 and 21'.

On the heating press rolls 21 and 21', the group of linear thermal conductors 10 and the soluble resin sheet 12 are heated and pressed, and are integrated with the linear thermal conductors in a state where the linear thermal conductors are embedded in the sheet 12. be done. The group of linear thermal conductors 10 and the soluble resin sheet 12 can be integrated by a method other than the method shown in FIG. 3, in which the soluble resin sheet 12 is heated and pressed from both sides of the group of linear thermal conductors 10. Alternatively, a method may be used in which the surface of the soluble resin sheet 12 is melted using a solvent or the like to integrate the linear thermal conductor 10 and the soluble resin sheet 12 without using the heat of the above method.

The soluble resin sheet 12 may be any material that can be dissolved in organic solvents, alkalis, acids, etc., such as polyester-based, polyamide-based, cellulose acetate-based, cellulose-based derivatives, and mixed sheets of such derivatives and cellulose pulp. etc. can be used. Alternatively, for example, a sheet made of a mixture of carboxymethyl cellulose and cellulose bulb may be coated or laminated with polyvinyl alcohol, or various resins may be appropriately combined. However,
Polyvinyl type is preferable because of its ease of handling, and among them, the saponification degree is 85 to 9 in order to easily dissolve it in hot water.
It is more preferable to use a partially saponified product of 0% and a degree of polymerization of about 500.

The width and thickness of the soluble resin sheet 12 in the present invention may be appropriately selected, but for example, the width is 0.5 m to 0.5 m.
1.5 m and a thickness of 10 to 200 trm are preferable for handling.

The composite sheet 22 that has passed through the heated press rolls 21 and 21' and is integrated is transferred to a pair of delivery rolls 23°2.
3', the composite sheet 22 is rolled up by the winding roll 24.
wind up.

Next, the composite sheet 22 is formed into a corrugated state. As a forming method, a conventionally known corrugate forming machine for forming corrugated fins of a corrugated heat exchanger, for example, a method in which the composite sheet 22 is compression-molded into a corrugate shape using a pair of corrugate forming presses, or a commercially available pleat forming machine may be applied. Bye. In particular, the wire diameter of the linear thermal conductor 10 is 200 mm.
If the material is as thin as μφ, an accordion-type pleating machine is fully applicable.

Next, as shown in FIG. 4, one end surface of the long pin fin member 25a (FIG. 3) molded into the corrugated shape, that is, the end surface joined to the heat dissipation member 8, is heated as shown in FIG. The pin fin member 25b is obtained by melting or mechanically removing the soluble resin 12 so that only 1 m/m) is exposed. On the other hand, in addition to the method described above, when manufacturing the composite sheet 22 illustrated in FIG. is obtained, and the resin removal step can be omitted. This pin fin member 25b is attached to the fin support member 8 of the radiator 7.
In order to join the fin support member 8 to the fin support member 8, the pin fin member 25b is cut to the size of the fin support member 8 to obtain a corrugated pin fin member 25c. It is recommended to use

Next, the corrugated pin fin member 25c is brazed to the surface 9 of the fin support member 8. Finally, pin fin member 2
The soluble resin sheet 12 remaining in 5c is melted and removed,
A heatsink with pin fins (see FIG. 6) is obtained, which is fitted into the stud 1 shown in FIG. 1 to function as a heatsink.

FIG. 7 shows I equipped with the heat sink for electronic equipment according to the present invention.
A cross-sectional view of the C package is shown. In this figure, a corrugated pin fin heat sink 27 is attached to an IC package 26, and the tC package 26 is mounted on a substrate 29 via a grounding pin 28. IC package 26
The heat generated inside the IC puff cage 26 is transmitted to the corrugated pin fin heat radiator 27 via the upper surface of the IC puff cage 26, and is radiated from the linear heat conductor 10.

The IC package with heatsink shown in Figure 7 is as follows.
Manufactured by The corrugated pin fin member 25b shown in FIG. 4 is brazed to the surface of a fin support member 30 made of copper, aluminum, or the like having good thermal conductivity. Next, the soluble resin sheet 12 remaining in the pin fin member 25b is dissolved and removed to obtain a heat sink with pin fins (see FIG. 8), which is cut to match the dimensions of the IC package 26 shown in FIG. A corrugated heat sink 27 (not shown) is obtained. Next, a compound 31 with good thermal conductivity, such as silicone grease, is applied to the surface of the IC package 26, and the IC
The package 26 and the corrugated heat sink 27 are joined together to form an I
A heatsink for C package is obtained.

FIGS. 9A and 9B show another embodiment of the heat sink for electronic equipment according to the present invention. That is, Figures 9A and 9B
The figures are front and side sectional views of a heat sink that cools the semiconductor element 33. In this figure, the stack 32 includes a refrigerant 3 that boils at a temperature below the allowable upper limit temperature of the semiconductor element 33.
4 is sealed and integrated with the radiator 35 of the present invention, and by cooling the refrigerant vapor condensing section 36 with air, the refrigerant vapor vaporized by the heat generated by the semiconductor element 33 is condensed, and the refrigerant vapor is condensed into the refrigerant boiling section 36. The electrode terminal 39 connected to the semiconductor element 33 is attached.

An example of a method for manufacturing the heat sink 35 shown in FIGS. 9A and 9B will be described with reference to FIG. 4 and FIGS. 1O to 11. The corrugated pin fin member 25b shown in FIG.
6. Wrap around the surface and braze (see Figure 10). Next, the soluble resin sheet remaining in the pin fin member 25b)
12 is melted and removed to form a pin fin radiator 35 (first
1A and 10) is obtained, and by joining the heat radiator 35, the refrigerant boiling part 37, and the header 38 by brazing or the like, a high-performance heat radiator for cooling semiconductor devices is obtained.

As above, the present invention has been described in detail with respect to a part of semiconductors, which is the background field of the present invention, but the present invention can be applied to other electronic devices that require expansion of heat dissipation area and further improvement of heat dissipation performance. A heatsink can be applied.

〔Example〕

Next, an example of a heatsink for electronic equipment according to the present invention will be shown, along with a comparative example of a U-shaped plate-shaped heatsink (see Fig. 12).
We compared the heat dissipation performance when using

Implementation■ Using a device similar to the device shown in Figure 3, a linear thermal conductor l
A pin fin member 25b formed by corrugating a sheet made of O and meltable resin 12 was manufactured under the following conditions, and a radiator with corrugated pin fins as shown in FIG. 7 was prepared as an example.

Linear heat conductor cross-sectional shape...circle Thickness (wire diameter)...200 side φ Material...copper creel Number of threads...500 Yarn feeding method...Bobbin rotation weft removal feed roll circumference Speed: 1m/min Reed pitch: 25.4 feathers/1nch (therefore pitch: 1 liter) Soluble resin sheet: PVA film Thickness: 200
(Manufactured by Soko Seiren Co., Ltd.) Heat press conditions: Temperature: 200℃, Load: None Corrugate forming machine: Manufactured by Toyo Koki Co., Ltd. (Accordion pleat machine) Corrugate forming conditions: Y1 = 1 piece/■■ , h=8m
m, corrugated pin fin arrangement density...Y=1 piece/
mm, the obtained corrugated pin fin member 25b was bonded to a copper plate (thickness: 0.2+n) using a brazing material (#@Nihon Genma Co., Ltd., melting point: 152°C) to create a radiator with corrugated pin fins. And so.

Northern Comparison ■ A commercially available radiator (manufactured by Suiyo Denki Kogyo Co., Ltd.) having a shape as shown in FIGS. 12A and 12B was used as a comparative example.

In order to investigate heat dissipation performance, we measured the amount of heat dissipated using a heat flow sensor.

Table 1 From Table 1, it was proven that the heat radiation performance is improved by using the corrugated pin fin radiator according to the present invention.

〔Effect of the invention〕

Since the heat sink for electronic equipment according to the present invention is configured as described above, it has high heat dissipation performance, and the wire diameter and arrangement density can be easily changed, thereby making it easy to create a heat sink with desired heat dissipation performance. can be manufactured.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of an electronic device equipped with a radiator with corrugated pin fins of the present invention, and FIG. 2 is a perspective view showing an example of a corrugated pin fin member used in the radiator of the present invention. Fig. 3 is a front view showing an example of the apparatus used to manufacture the bisi-fin member, and Fig. 4 shows the top part of the linear heat conductor by partially removing the top resin of the corrugated pin fin member. FIG. 5 is a front view showing the exposed state; FIG. 5 is a perspective view showing the corrugated pin fin member cut into a predetermined size;
The figure shows a heat dissipation member and a corrugated pin fin member joined together.
FIG. 7 is a front view showing a state in which a heat sink is obtained by melting and removing the resin in the pin fin member, FIG. 7 is a cross-sectional view of an IC package using the heat sink according to the present invention, and FIG.
9A is a front view showing a heatsink with a corrugated pin fin used in the IC pancase of the present invention; FIG. 9A is a front view of a device for cooling a semiconductor device using the heatsink according to the present invention; FIG. 9B 10 is a side sectional view thereof, and FIG. 10 is a perspective view showing the pipe and fin member integrated by winding a corrugated pin fin member around a pipe.
11B is a front view showing a state in which a corrugated pin fin-equipped radiator is obtained by dissolving and removing the soluble resin in the pin fin member, FIG. 11B is a cross-sectional view thereof, and FIG. 12A is a
is a front view of a commercially available U-shaped plate-shaped heatsink;
Figure 2B is a sectional view thereof. 7.27.35... Heat sink, 10... Linear thermal conductor, 12... Meltable resin sheet, 25a, 25b... Corrugated pin fin member, 8
．． 30...Fin support member. 5a Figure 2 Figure 5c Figure Salary 9A Figure 1B Figure 9B (A) Figure (A) Salary Figure 12 (B) (B)

Claims (1)

[Claims] A plurality of linear heating elements comprising a fin and a fin support member that supports the fin and mediates heat conduction with the electronic device, and the fins are arranged parallel to each other at intervals and curved in a corrugate shape. A heatsink for electronic equipment with a corrugated pin fin characterized by being made of a conductor.