JPH05283878A - Heat sink cooling fan excellent in heat radiation property, and its manufacture - Google Patents

Abstract

PURPOSE:To improve heat radiation performance by constituting a heat sink out of a bottom plate and a hollow projection standing erect on the bottom plate and united with the bottom plate, and forming the peripheral wall of the hollow projection out of a plurality of parallel plate-type fins standing erect on the bottom plate or pin-type fins. CONSTITUTION:For a heat sink 35, a bottom plate 31 consisting of a good heat conductor, and thereon, an erect hollow projection 36 having a hollow area 32, in short, a hollow section, and, surrounding this hollow region 32, a hollow projection 36 are made. The peripheral wall of the hollow projection is constituted of a row of heat radiation fins 34 made of a good heat conductor erect on the bottom plate 31. The heat radiation fins 34 in a row are constituted of a plurality of unit fin elements 33. The heat generated by a chip is conducted to the heat radiation fins 34 in a row through the bottom plate 31 of the heat sink 35 by heat conduction. On the other hand, cool air for cooling is supplied to the hollow area 32 of the fins in a row through the opening 42 at the center of a top board, and then it takes the heat off from the heat radiation fins 34 in a row.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat sink for a single-chip or multi-chip module, for example, a multi-chip module for closely sealing a plurality of chips, such as large-scale integrated circuits (LSI), which generate heat, in close proximity. The present invention relates to a heat sink cooling fin used for cooling MCM) and a manufacturing method thereof.

[0002]

2. Description of the Related Art In response to the rapid increase in the amount of information processing and the demand for high-speed information processing, electronic components represented by ICs and LSIs are becoming highly integrated by miniaturizing electronic circuits in chips. , The adoption of multi-chip module (MCM) that closes multiple highly integrated chips together and encapsulates them rapidly is increasing.

This multi-chip module is shown in a schematic perspective view before sealing in FIG. 1 (a), and in a sectional view after sealing in FIG. 1 (b).
As shown in Fig. 1 (c), a side view with the heatsink attached is shown in Fig. 1 (c). Multiple LSI chips 12 are mounted on the multilayer ceramic wiring board (MLS) 11 and the cap 1
3 is hermetically sealed to form a multichip module package 15, and input / output pins 14 are used to input / output electric signals.

Since a plurality of highly integrated chips 12 are mounted on each, both the heat generation density and the heat generation amount are reduced to the conventional single IC.
It is dramatically increasing compared to packages and the like, and it is necessary to cool each chip to keep it below the allowable temperature in order to ensure circuit operation speed and improve reliability. Therefore, in order to efficiently dissipate the heat generated from the chip 12 to the outside, a structure in which a heat sink 16 is attached to the multi-chip module package 15 is devised as shown in FIG. (Hakuhodo Publishing, '87, edited by The Japan Society of Mechanical Engineers, cooling technology for electronic devices, p30-32). A cooling working fluid is forcibly supplied to the heat sink 16 to cool it.

The cap 13 and the chip 12 are made of materials having the same linear expansion coefficient, and the chip 12 die-bonded to the cap 13 transfers the generated heat from the die bonding material 17 to the cap 13 and the heat sink 16. Are cooled by being carried away through the heat conduction of the heat sink 16 and through the heat transfer from the heat sink 16 to the working fluid.

Conventionally, as this cooling method, forced air cooling in which air is forcibly supplied as a working fluid to a heat sink is widely used because the structure of the cooling device is simple and convenient. As a heat sink shape used for this forced air cooling, as shown in a perspective view in FIG. 2 (a), a channel fin type heat sink 23 having a parallel plate type heat radiation fin 22 (hereinafter referred to as a heat radiation plate) on a bottom plate 21. Alternatively, as shown in FIG. 2B, a pin fin type heat sink 25 in which pin type fins 24 (hereinafter referred to as heat dissipation pins) are arranged on a bottom plate 21 is typical. In the figure, white arrows indicate the flow of air as a working fluid.

In order to cope with cooling of a heating element having a large heat generation amount and a large heat generation density such as a multi-chip module by using these conventional heat sinks, the heat radiation area of the heat sink is increased and the air flow rate passing through the heat sink is increased. It is necessary to improve the heat dissipation ability by increasing the. Therefore, in order to increase the heat dissipation area with the same occupied volume without increasing the size of the heat sink, the fin pitch and the fin interval must be reduced.

However, the conventional heat sink manufacturing method is a method by extrusion, cutting, die casting, etc., and it is difficult to obtain a necessary heat radiation area by such a method.

Further, in the conventional cooling method, as shown in FIG.
Cooling is performed by supplying air as a working fluid to the heat sink in the direction parallel to the bottom plate 21 as shown in (a) or in the direction perpendicular to the bottom plate 21 as shown in FIG. Therefore, simply decreasing the fin pitch and the fin interval causes an increase in flow path pressure loss due to the frictional resistance of the heat sink or the heat sink pin, and most of the supplied air bypasses the heat sinks 23 and 25. It does not contribute to cooling. Also, if an attempt is made to increase the flow rate of the air passing through the heat sink, the flow path pressure loss due to frictional resistance increases in proportion to the 2nd to 3rd power flow velocity, so a high-power blower with sufficient blowing capacity is required. Therefore, problems of space and noise occur. As described above, it is very difficult to cool the multi-chip module below the allowable temperature by the conventional cooling method using the heat sink.

[0010]

SUMMARY OF THE INVENTION A main object of the present invention is to supply a working fluid for cooling to a heat sink channel inlet and to contribute to cooling when cooling a multi-chip module having a large heat generation density and a large heat generation amount. It is an object of the present invention to provide a heat sink cooling fin and a method for manufacturing the same, which can exhibit epoch-making heat dissipation performance by collecting the warmed working fluid in the vicinity of the heat sink passage outlet.

A further object of the present invention is to bypass the working fluid due to the pressure loss caused by the frictional resistance in the flow path, although it has a much larger heat dissipation area than the conventional channel fins and pin fins having the same occupied volume. In addition, the fluid used for cooling is not heated in other parts of the heat sink and does not stagnant in the vicinity of the flow path of the heat sink, which enables efficient cooling. A cooling fin and a manufacturing method thereof are provided.

More specifically, an object of the present invention is that when it is used under forced air cooling, it is several times to several tens of times larger than the conventional channel fin type heat sink and pin fin type heat sink used under the same forced air cooling. It is an object of the present invention to provide a heat sink cooling fin having extremely high heat dissipation performance and a manufacturing method thereof.

[0013]

In order to solve the problem, the inventors of the present invention provide one kind of hollow portion at the center of a fin row composed of a plurality of unit fin elements, that is, a heat radiating plate and a heat radiating pin. The present invention has been completed, knowing that it is effective to arrange a plurality of such fin rows in a staggered or staggered manner.

Here, the gist of the present invention is that it is composed of a bottom plate and a hollowed-out protruding body which is upright on the bottom plate and is integral with the bottom plate. The heat sink cooling fin is formed by a fin array including a plurality of parallel plate type fins or pin type fins standing upright on the bottom plate.

Further, from another surface, it is composed of a bottom plate and a hollowed-out projection-shaped body which is upright on the bottomed plate and is integral with the bottom plate. The peripheral wall of the hollowed-out projection-shaped body is formed on the bottom plate. A heat sink cooling fin, which is formed of a fin array composed of a plurality of upright parallel plate type fins or pin type fins, and supplies or sucks a working fluid from a hollow portion of the hollow body.

[0016] From another side, a bottom plate, a hollow protrusion-shaped body which is upright on the bottom plate and which is integral with the bottom plate, and a part of the bottom plate which is provided around the hollow protrusion-shaped body. A non-protruding portion, and the peripheral wall of the hollowed-out protrusion-shaped body is formed by a fin array consisting of a plurality of parallel plate fins or pin-shaped fins standing upright on the bottom plate. The heat sink cooling fin is characterized in that the working fluid is supplied or sucked from the hollow portion, and the working fluid is sucked or supplied from the non-protrusion portion which is an outer peripheral portion of the fin row.

Further, according to the present invention, a material having a bottom plate and a hollow protrusion-shaped body which is upright on the bottom plate and is integral with the bottom plate is prepared, and the protrusion-shaped body is stretched at the same pitch as a required fin pitch. The wire array is made to run, and the wire array and the material are pressed in a state where a working liquid containing abrasive grains is interposed between the wire array and the material, and the material is ground by the grinding action of the abrasive particles. In the method for manufacturing a heat sink cooling fin, a parallel groove row or a parallel pin row having a predetermined depth and width is formed in the hollow protrusion-shaped body. The plurality of fin rows may be spaced apart from each other and arranged in a plurality of sets to form a heat sink cooling fin.

According to still another aspect, the present invention provides a bottom plate,
A material having a plurality of hollow protrusion-shaped bodies which are upright on the bottom plate and which are integrated with the bottom plate is prepared, and a wire row stretched on the protrusion-shaped body at the same pitch as the required fin pitch is run. The wire row and the material are pressed in a state in which a working fluid containing abrasives is interposed between the wire row and the material, and the material is formed into a hollowed-out protruding shape by the grinding action of the abrasive grain. A method for manufacturing a heat sink cooling fin, characterized in that parallel groove rows or parallel pin rows having a predetermined depth and width are formed.

According to a preferred embodiment of the present invention, there is prepared a material having a bottom plate and a plurality of aligned or staggered blanking protrusion-shaped bodies which are upright on the bottom plate and which are integral with the bottom plate. When the projection-shaped body is subjected to abrasive grain grinding processing with a wire saw, the wire may be detoured at the non-projection portion.

[0020]

The present invention will now be described in more detail with reference to the accompanying drawings. 3 (a), (b), and (c) show an example of the heat sink cooling fin according to the present invention by a plan view, a side view, and a sectional view, respectively, and FIG. It is an enlarged view of the B section of FIG.

The heat sink 35 shown in the figure has a bottom plate 31 made of a good conductor of heat, a hollow region 32 on the bottom plate 31, that is, an upright hollow projecting protrusion 36 having a hollow portion, and a hollow region 32 surrounding the hollow region 32. The heat dissipating fin array 34 is made of a good conductor of heat and stands upright on the bottom plate 31 to form a protrusion-shaped body 36. The heat radiation fin array 34 is composed of a plurality of unit fin elements 33 (heat radiation plates in the illustrated example). The radiating fin row 34 is arranged on the bottom plate 31 in a plurality of sets (in this case, 6 ×
6 = 36 sets) are arranged.

In this heat sink 35, the bottom plate dimension W
× L × T, fin height H, cross-sectional dimension 1 ₁ × 1 ₂ on the bottom plate surface of the hollow region, fin row dimension a ₁ × a ₂ , fin row spacing c ₁ , c ₂ , fin plate thickness t and the heat dissipation plate pitch p can be set appropriately. FIG. 4 is a diagram for explaining an example of a forced air cooling method using a heat sink according to the present invention using the heat sink shown in FIG. 3, where FIG. 4 (a) is a sectional view taken along line AA and FIG. 4 (b) is It is a BB sectional view and the same (c) is a CC sectional view.

In the illustrated embodiment, a top plate 41 is attached to the heat sink 35, and an opening is provided in the top plate 41 at a position corresponding to the hollowed-out portion of the radiation fin array.
As a result, the top plate is installed on the upper surface of the heat dissipation plate in close contact with the heat dissipation plate so as to form a rectangular cross-section flow path together with the bottom plate 31 and the heat dissipation fin array 34. The heat generated from the chip, which is a heating element, is transferred to the radiation fin array 34 by heat conduction through the bottom plate 31 of the heat sink. On the other hand, cold air for cooling is supplied to the hollow region 32 of the fin array from the opening 42 at the center of the top plate, and thereafter, in the rectangular cross-section flow path surrounded by the bottom plate 31, the radiation fin array 34, and the top plate 41. While passing, heat is taken from the radiating fin row 34. The air thus deprived of heat and warmed is sucked and collected from the non-projection portion around the radiation fin array 34.

In this method, cooling air is supplied around the heat dissipating fin array 34, and suction is made through the opening 42 at the center of the top plate.
The flow direction of the cooling air may be reversed so as to recover it. In the present invention, the case where the working fluid is supplied or suctioned from the hollow portion of the hollow protrusion shape body and the working fluid is suctioned or supplied from the outer peripheral portion of the fin array, that is, the non-projection portion has been described as an example. Even if the working fluid is supplied or sucked from the hollow portion of the shaped body, the effect similar to the above is obtained.

FIG. 10, which will be described later, shows an example thereof.
(A) is a sectional view taken along the line AA, and FIG. 10 (B) is a sectional view taken along the line BB.
FIG. 10C is a cross-sectional view taken along the line CC, and FIG.
It is an enlarged view of the D portion of (b). Heat sink shown in Figure 10
103 is a resin top plate 10 which is a heat insulating material as shown in FIG.
I installed 4. The radiating fin rows 101 provided on the bottom plate 102 are arranged in line, and air as a working fluid is sucked from the hollow portion, that is, the opening of the top plate 104 provided at a position corresponding to the hollow region 105. It

Similarly, FIG. 11, which will be described later, shows a case where air is supplied from the hollow region 115 and air is sucked from the non-protruding portion around the radiation fin array 111. Figure 11 (a) shows A-A
Sectional view, Figure 11 (b) is BB sectional view, Figure 11 (c) is C-
11 is a sectional view taken along the line C, and FIG. 11D is an enlarged view of a portion D in FIG. 11B.

As described above, according to the present invention, the cooling effect of the radiation fin array can be made uniform and efficient by sucking and supplying the working fluid from the hollow region of the hollow protrusion. Further, if the working fluid is a liquid, it goes without saying that a further effect is brought about.

The radiating fin array of the heat sink is not limited to a particular one, and as shown in FIG. 5A, the radiating fin array standing upright on the bottom plate 31 in two directions around the hollow area 51.
Placement of 52, as shown in Fig. 5 (b), hollow area
A heat radiation fin array 54 arranged upright on the bottom plate 31 around 53, a heat radiation fin array 56 standing upright on the bottom plate 31 around the hollow region 55 as shown in FIG. 5C. As shown in FIG. 5D, even if a radiating pin row 58 standing upright on the bottom plate 31 is arranged around the hollow area 57,
It is possible to apply the cooling method according to the invention on the same principle. Also in this case, it is desirable that the bottom plate, the radiation fin array, and the radiation pin array are good conductors of heat.

According to the structure of the present invention, all the cooling air supplied uniformly flows into the plurality of flow paths in the heat sink constituted by the bottom plate, the radiation fin array, and the top plate.
Since it passes through, cooling air does not flow around the outside of the heat sink, unlike the conventional cooling method, and efficient cooling can be performed with a small air flow rate. For this reason,
It is unlikely to be affected by the flow path frictional resistance that occurs when the fin pitch and fin spacing are reduced to increase the heat dissipation area of the heat sink as in the conventional case. Next, a method of manufacturing the heat sink cooling fin according to the present invention will be described.

FIG. 6 is a perspective view showing a work material which is a starting material of the heat sink shown in FIG. 3 as an example of a starting material for manufacturing the heat sink cooling fin according to the present invention.

This work material has a bottom portion 31 having the same dimensions (W × L × T) as the heat sink shown in FIG. 3, a cross-sectional dimension (1 ₁ × 1 ₂ ) and a plane dimension (a) on the bottom plate surface of the hollow region. ₁ x a
₂ ) It is composed of a plurality of protrusions 61 having a mouth-shaped horizontal section and a height H, and is made of a material having a large thermal conductivity such as copper or aluminum alloy. Distance c _1, c ₂ of each projection 61 is identical to the spacing c _1, c ₂ of the fin rows between the aforementioned.

The work itself is, for example, a method of cold forging a plate having a plane dimension W × L and a thickness larger than T and smaller than T + H, or a plane dimension W × L and a thickness T.
Method of removing + H plate by machining, electrical discharge machining, etc.,
Further, a plate having a plane dimension W × L and a thickness T is a cross-sectional dimension (1 ₁ × 1 ₂ ) and a plane dimension (a ₁
It is formed by a method of attaching a frame material of height H having a mouth-shaped horizontal cross section of xa ₂ ) by brazing.

7A and 7B are views for explaining the method of manufacturing the heat sink shown in FIG. 3, wherein FIG. 7A is a schematic perspective view of the wire saw processing portion, and FIG. 7B is a front view thereof. The wire 70 sent from a wire feeding device (not shown) from the left-hand direction toward the drawing, for example, a piano wire is a groove roller 72a,
The wires 72b, 72c, 72d are wound around and wound to form a wire row 71 having a predetermined pitch and width. At this time, the wire row 71a that is in contact with the protrusion of the workpiece 74 and is involved in the machining is 4
It is orbited by individual groove rollers 72a, 72b, 72c, 72d,
The wire row 71b that is not involved in the processing includes three groove rollers 72.
It is desirable that only a, 72b, and 72d circulate in a triangular shape to bypass the non-projecting portion. This prevents the row of wires in the non-processed part from hitting each radiating pin element formed by vibration or the like and falling down or cutting the bottom plate, and the agglomerates or foreign matters in the working liquid are brought in between the groove roller and the wire. This is to prevent the derailment and disconnection of the wire.

From this, of course, the wire row which is not involved in the processing may be wound only by the two groove rollers 72a and 72b, but the point that the repeated bending of the wire is minimized and the groove roller is used. As described above, the three groove rollers are used in order to reduce the force as much as possible.
It is desirable to go around 72a, 72b, 72d.

The wire thus wound around the groove roller to form the wire row is wound in the wire winding device (not shown) in the right-hand direction in the drawing. At least one of the four groove rollers 72a, 72b, 72c, 72d is rotationally driven to run the wire row in one direction. A work piece 74 mounted on the mounting table 73 and fixed so that its two sides are parallel to the wire is pushed against the traveling wire row by raising it together with the mounting board, and the wire row and the work piece By supplying the machining liquid 76 containing abrasive grains from the nozzle 75 in between, only the portion of the projection of the workpiece to which the wire row is pressed by the grinding action of the abrasive grains is scraped off.

That is, the concrete processing operation of the heat radiation fin array composed of the heat radiation plate or the heat radiation pin will be further described. First, taking the heat sink of the form shown in FIG. 3 as an example, as shown in FIG. After forming a plurality of groove rows on two opposite sides of the hollowed-out protrusion-shaped body by elevating the mounting table by a predetermined height H of the heat radiation fin row from the position where the above-mentioned wire row starts to come into contact with the work piece, Is once separated from the wire row, and the work piece 83 is pressed against the wire row 82 in the direction in which the groove row 81 and the wire row 82 are orthogonal to each other, and similarly ground to form a fin row composed of a plurality of heat dissipation plates. It

In addition to manufacturing by grinding twice as described above, as shown in FIGS. 9 (a) and 9 (b), wires 91a and 91b are also used.
Are set in two directions orthogonal to each other, and the work piece
It is possible to form the hollow projections 93 into a desired fin array by the same principle. At this time, the orthogonal wire rows 91a and 91
Since it cannot be set at the same height as b, the groove depth to be cut is slightly different in the two directions orthogonal to each other, but since the difference is at most about the wire diameter, there is no practical problem at all.

In the present invention, the case where the fin rows are arranged in an array on the bottom plate at a predetermined interval has been described, but it is needless to say that the fin rows may be arranged in a staggered pattern or at random. .. Further, it goes without saying that the sizes of the hollow protrusion-shaped bodies may be different from each other. Next, the operation of the present invention will be described more specifically by way of its examples.

[0039]

[Embodiment 1] As shown in FIG. 3, 6 × 6 = 36 pure aluminum radiating fin rows 34 are arranged in an array on the bottom plate 31, and the dimension of each part is L = W = 100 mm, a
₁ = a ₂ = 10.0 mm, c ₁ = c ₂ = 7.0 mm, 1 ₁ = 1 ₂ =
5.05 mm, T = 2.0 mm, H = 10.0 mm, p = 0.4 mm, t = 0.
A cooling device in which a resin top plate 41 as a heat insulating material as shown in FIG. 4 was attached to a heat sink 35 having a size of 15 mm, a sheet-like heater was attached to the back surface of the heat sink, and a cooling performance test was conducted. At this time, the cooling air is supplied to the hollow portion of each fin row as shown in FIG. 4, and is sucked from the non-projecting portion on the outer peripheral portion of each fin row.

When the calorific value and the air flow velocity were changed at the cooling air inlet temperature of 25 ° C., the calorific value was 180 W and the cooling air flow rate was
Under the conditions of 6000cc / sec (flow rate of cooling air to be supplied to each set of fins is 165cc / sec, flow velocity in heat sink cooling fins is 1.5m / sec), pressure loss in heat sink is about 1080Pa, The cooling performance showed a resistance of about 0.3K / W.

This has a heat generation density of 1.8 W / cm ² and can be cooled. In conventional forced air cooling, the heat generation amount of the package alone is up to about 15 W and the heat generation density up to about 1 W.
Considering that / cm ² was the limit that can be cooled, it can be seen that it exhibits epoch-making cooling performance.

[Embodiment 2] As shown in FIG. 10, a radiating fin array 101 made of an aluminum alloy is placed on a bottom plate 102 at 4 × 4 = 16.
They are arranged in pairs and the dimension of each part is L = 60m
m, W = 70 mm, a ₁ = 12.2 mm, a ₂ = 9.5 mm, c ₁ = 2.5
mm, c ₂ = 4.0 mm, ₁₁ = 2.3 mm, T = 2.0 mm, H = 1
Cooling performance by using a cooling device in which a resin top plate 104 that is a heat insulating material is attached to a heat sink 103 with 0.0 mm, p = 0.5 mm, and t = 0.2 mm, and a sheet-like heater is attached to the back surface of the heat sink. The test was conducted. At this time, the cooling air is sucked from the hollow portion 105 of each fin row 101 to flow into the inter-fin channel from the outer peripheral portion of each fin row.

When the calorific value and the air flow velocity were changed at the cooling air inlet temperature of 25 ° C., the calorific value was 100 W and the cooling air flow rate was 3200.
cc / sec (flow rate of cooling air supplied to each fin array)
Under the conditions of 200 cc / sec and the flow velocity in the heat sink cooling fin flow path of 1.4 m / sec), the cooling performance of the heat sink was about 900 Pa and the thermal resistance was about 0.4 K / W.

This has a heat generation density of 2.4 W / cm ² , and in conventional forced air cooling, the maximum heat generation of the package alone is about 15 W and the heat generation density is about 1 W / cm ^2.
Considering that it was the limit that can be cooled, it shows epoch-making cooling performance.

[Embodiment 3] As shown in FIG. 11, a fin array 111 composed of heat dissipation pins is formed on the bottom plate 112 by 6 × 6 = 36.
They are arranged in pairs and the dimensions of each part are L = W =
100 mm, a ₁ = a ₂ = 12.3 mm, c ₁ = c ₂ = 4.0 mm, 1
₁ = 1 ₂ = 3.1 mm, T = 1.0 mm, H = 5.0 mm, p = 0.5
The cooling performance test was conducted by using a cooling device in which a resin top plate 114 as a heat insulating material was attached to a heat sink 113 with mm and t = 0.2 mm, and a sheet heater was attached to the back surface of the heat sink. At this time, the cooling air is supplied from the hollow portion 115 of each fin row 111 and sucked from the outer peripheral portion of each fin row.

When the calorific value and the air flow rate were changed at the cooling air inlet temperature of 25 ° C., the calorific value was 250 W and the cooling air flow rate was 6000.
cc / sec (flow rate of cooling air supplied to each fin array)
165cc / sec), the cooling performance was about 2200Pa pressure loss and about 0.25K / W thermal resistance in the heat sink.

This has a heat generation density of 2.5 W / cm ² and can be cooled. In conventional forced air cooling, the heat generation amount of the package alone is about 15 W and the heat generation density is about 1 W / cm ^2. Considering that it was a possible limit, it shows epoch-making cooling performance.

[0048]

The heat sink cooling fin according to the present invention has a far larger heat radiation area per the same occupied volume than the conventional heat sink, and the working fluid for cooling passes through the heat radiation portion at a relatively small flow rate. Therefore, compared with the conventional cooling method, it is possible to significantly increase the cooling capacity while suppressing an increase in pressure loss due to flow path friction. Therefore, it is possible to cool a multi-chip module having a very large heat generation amount and a high heat generation density to an allowable temperature by forced air cooling using a conventional small blower. Further, the heat sink cooling fin according to the present invention can be applied not only to cooling the multi-chip module but also to cooling the single-chip module.

[Brief description of drawings]

1A, 1 </ b> B, 1 </ b> B, and 1 </ b> C are a perspective view, a cross-sectional view, and a side view, respectively, for explaining the outline of a multichip module and the cooling method.

2 (a) and 2 (b) illustrate a cooling mode performed by supplying a working fluid to a conventional radiator plate for forced air cooling and a fin array, respectively.

3 (a), (b), (c), and (d) are a plan view, a side view, a cross-sectional view, and a partial view of a heat sink for a multichip module using a cooling fin of the present invention, respectively. FIG.

4 (a), (b) and (c) are cross-sectional views of a heat sink using a cooling fin according to the present invention,
It is a sectional view and a sectional view.

5 (a), (b), (c), and (d) are perspective views of cooling fin arrays of the heat sink of the present invention.

FIG. 6 is a perspective view of a work piece used to form heat sink cooling fins in accordance with the present invention.

7 (a) and 7 (b) are explanatory views of the method for manufacturing the wire saw and the heat sink cooling fin of the present invention.

FIG. 8 is an explanatory diagram of a positional relationship between a wire row of a processed portion and a material to be processed.

9 (a) and 9 (b) are explanatory views of a positional relationship between a wire row of a processed portion and a material to be processed.

10 (a), (b), (c), and (d) are cross-sectional views, cross-sectional views, cross-sectional views, and partially enlarged views of another example of the heat sink cooling fin of the present invention. ..

11 (a), (b), (c), and (d) are a cross-sectional view, a three-view drawing, a cross-sectional view, and a partially enlarged view, respectively, of yet another example of the heat sink cooling fin of the present invention. is there.

[Explanation of symbols]

 31: Bottom plate 32: Hollow area (hollow-out portion) 33: Unit fin element 34: Fin row 35: Heat sink 36: Hollow-out protrusion shape body

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location H01L 23/467 H05K 7/20 T 8727-4E

Claims (7)

[Claims] 1. A plurality of parallel plate fins or pin-shaped fins, each of which is composed of a bottom plate and a hollow-projection-shaped body on the bottom plate and which is integrated with the bottom plate, and which is provided upright on the bottom plate on a peripheral wall of the hollow-projection-shaped body. A heat sink cooling fin, characterized by forming a fin array of fins. 2. A plurality of parallel flat plate type fins or pin-shaped fins, which are composed of a bottom plate and a hollowed-out protrusion-shaped body which is integrated with the bottom plate on the bottom plate, and which are upright on the bottom plate on a peripheral wall of the hollowed-out protrusion-shaped body. A heat sink cooling fin, characterized in that a fin row composed of fins is formed, and a working fluid is supplied or sucked from a hollow portion of the hollowed-out protruding body. 3. A plurality of parallel flat plate type fins or pin-shaped fins, each of which is composed of a bottom plate and a hollowing-out projection-shaped body on the bottoming plate, which is integrated with the bottoming plate, and which is provided upright on the bottom plate on a peripheral wall of the hollowing-out projection-shaped body. A fin row formed of fins is formed, and the working fluid is supplied or sucked from the hollow portion of the hollowed-out protruding body, and the working fluid is sucked or supplied from the outer peripheral portion of the fin row, that is, the non-projection portion. Heat sink cooling fins. 4. A wire row stretched at the same pitch as the pitch of the required fins is made to run on the projection-shaped body of a material having a bottom plate and a hollowed-out projection-shaped body integrated with the bottom plate on the bottom plate, The wire row and the material are pressed against each other with a working fluid containing abrasive grains interposed between the wire row and the material, and a predetermined protrusion is formed on the hollowed-out protrusion-shaped body of the material by the grinding action of the abrasive grain. The method for manufacturing a heat sink cooling fin according to claim 1, wherein parallel groove rows or parallel pin rows having a depth and a width are formed. 5. A heat sink cooling fin in which a plurality of sets of the heat sink cooling fin rows according to claim 1, 2 and 3 are arranged so as to be spaced apart from each other. 6. The protrusion-shaped body made of a material having a bottom plate and a plurality of hollow protrusion-shaped bodies integrated with the bottom plate on the bottom plate,
The wire row stretched at the same pitch as the required fin pitch is run, and the wire row and the material are pressed in a state in which a working fluid containing abrasive grains is interposed between the wire row and the material, 6. The method for manufacturing a heat sink cooling fin according to claim 5, wherein the hollow projection shape body of the material is formed with parallel groove rows or parallel pin rows having a predetermined depth and width by the grinding action of the abrasive grains. 7. A wire is diverted at a non-protruding portion when an abrasive grain grinding process is performed on the protrusion-shaped body of a material having a bottom plate and a plurality of hollow protrusion-shaped bodies integrally formed on the bottom plate with a wire saw. The method for manufacturing a heat sink cooling fin according to claim 5, wherein.