JPH05121604A - Cooling system - Google Patents

Abstract

PURPOSE:To provide a cooling system which can be reduced in size and, at the same time, can excellently cool heat generating bodies. CONSTITUTION:After a flexible sealing member 5 is put on the peripheral surface of a substrate 1 mounted with semiconductor chips, the semiconductor chips 4 are sealed by sticking a cold plate 6 to the upper edge of the member 5. Then a liquid 8 having an insulating property is enclosed in a cap 7 constituted of the member 5 and plate 6. When the chips 4 generate heat, the heat is transferred to the plate 6 through the liquid 8 enclosed in the cap 7. The heat transferred to the plate 6 is subjected to direct heat exchange carried on by a coolant flowing through flow passages 6a formed in the plate 6. Therefore, the chips 4 can be excellently cooled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device used for cooling a heating element such as a semiconductor chip.

[0002]

2. Description of the Related Art Since a heating element such as a semiconductor element generates heat during operation, cooling is performed by a cooling means in order to improve reliability and maintain performance.

9 and 10 are sectional views showing an example of a conventional cooling device for a semiconductor element.

In the cooling device shown in FIG. 9, the semiconductor chip 1
01 is disposed in a space 104 formed by the substrate 102 and the heat transfer block 103, and the semiconductor chip 101 is provided.
One surface (the lower surface in the drawing) is connected to the substrate 102 via the bump 105, and the stud 106 is connected to the other surface (the upper surface in the drawing). In addition, a space 104 formed between the substrate 102 and the heat transfer block 103
Is filled with He gas.

The stud 106 is arranged so as to be substantially in contact with the side wall of the hole 103a formed in the heat transfer block 103, and the stud 106 is pressed against the semiconductor chip 101 by the spring 107 provided in the hole 103a. Further, on the surface of the heat transfer block 103 opposite to the substrate 102 (upper side in the figure), a flow path 108 through which a cooling medium flows is formed.
The cold plate 109 in which is formed is connected.

In the above-described conventional cooling device, when heat is generated in the semiconductor chip 101, this heat is transmitted to the stud 106, and the heat transfer by the catalyst of the stud 106 and the heat transfer block 103 and the heat transfer block 103 through He gas.
Be transferred to. Then, the heat transfer block 103 is cooled by the cooling medium flowing in the flow path 108 of the cold plate 109, whereby the semiconductor chip 101 is cooled.

As described above, in the above-described conventional cooling device, even if there are variations in the height or inclination of the upper surface of the semiconductor chip 101 mounted on the substrate 102, they are alleviated and the cold plate 109 is effectively provided. In order to transfer heat, a spring 107 is arranged between the upper portion of the hole 3a formed in the heat transfer block 103 and the stud 106 to form a mechanically flexible heat transfer structure.

By the way, in the conventional cooling device shown in FIG. 9, the heat transfer path from the semiconductor chip 101 to the stud 106, the heat transfer block 103, and the cold plate 109 is long, and it is difficult to reduce the thermal resistance during that time. There was a problem.

Further, since the number of parts is large, the structure is complicated, and the thickness becomes large, it is difficult to reduce the size.

Further, in the cooling device shown in FIG. 10, a plurality of semiconductor chips 111 having fins 110 connected to the upper portion thereof are used.
Is mounted on the substrate 112, and a duct 114 for flowing the cooling air 113 to the fin 110 is arranged above each fin 110.

The duct 114 is composed of a duct body 115 and a nozzle 116 protruding above each fin 110. Cooling air is flown from the nozzle 116 to radiate the heat of the semiconductor chip 111 to the atmosphere from the fin 110. Was there.

By the way, in the conventional cooling device shown in FIG. 10, since the nozzle 116 is formed so as to project from the duct main body 115 to the side of each semiconductor chip 111, the overall thickness of the duct becomes thicker and the miniaturization can be achieved. Was difficult.

[0013]

As described above, as shown in FIG.
In the conventional semiconductor chip cooling device shown in (1), the structure is complicated due to the large thermal resistance and the large number of heat transfer structure parts, and the thickness also becomes thicker, making it difficult to achieve miniaturization. ..

In the conventional semiconductor chip cooling device shown in FIG. 10, the entire duct becomes thicker, and it is difficult to reduce the size of the duct.

The present invention has been made for the purpose of solving the above-mentioned problems, and an object of the present invention is to provide a cooling device which can be miniaturized and which can favorably cool a heating element.

[0016]

In order to solve the above-mentioned problems, according to the invention of claim 1, a flexible seal member is provided on the peripheral surface of a substrate on which a heating element is mounted, and A heat conduction plate disposed on the seal member so as to seal the heating element, and a fluid having an insulating property is enclosed in a space surrounded by the substrate, the seal member and the heat conduction plate. It is characterized by

According to the second aspect of the invention, the fins connected to the heating element, the duct main body for introducing the cooling air, and the cooling air formed so as to project inside the duct main body are provided to the fins. It is characterized in that it is provided with a duct consisting of a flowing nozzle.

[0018]

According to the first aspect of the present invention, even if there are variations in height and inclination when a plurality of heating elements are mounted on a substrate, the heat of each heating element is satisfactorily transmitted to the heat conduction plate and cooled. Moreover, since the heat transfer structure is not mechanical but simplified by performing the heat transfer through the fluid, the size can be reduced.

According to the present invention as defined in claim 2,
By forming the nozzle for flowing the cooling air to the fin connected to the heating element so as to project to the inside of the duct body, the thickness of the duct can be reduced and cooling can be performed.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the illustrated embodiments.

<First Embodiment> FIG. 1 is a sectional view showing a cooling device according to a first embodiment of the present invention, and FIG. 2 is an exploded perspective view thereof. As shown in both figures, in this embodiment, a plurality of semiconductor chips 4 are mounted on a substrate 1 to which pins 2 are connected via bumps 3. Each semiconductor chip 4 has a peripheral surface on the substrate 1. It is sealed by a cap 7 which is composed of a flexible seal member 5 disposed in the above and a cold plate 6 disposed above the seal member 5. The substrate 1 and the seal member 5 and the cold plate 6 and the seal member 5 are joined together by solder, adhesive, welding or the like.

A channel 6a through which a cooling medium (for example, water) flows is formed in the cold plate 6, and the cooling medium is supplied from the supply port 6b and discharged from the recovery port 6c.

In addition, a cap 7 in which the semiconductor chip 4 is sealed is filled so as to be filled with an insulative liquid (for example, silicon oil) 8.

The cooling device according to this embodiment is configured as described above, and when heat is generated in each semiconductor chip 4, this heat is passed through the liquid 8 sealed in the cap 7 to the cold plate 5. Be transmitted to. Cold plate 6
The heat transferred to the semiconductor chip 4 can be satisfactorily cooled by directly exchanging heat with the cooling medium flowing in the flow path 6a.

Further, the strain generated by the heat generation of the semiconductor chip 4 due to the difference in the coefficient of thermal expansion of the substrate 1, the cold plate 6, and the liquid 8 in the cap 7 is absorbed by the flexible seal member 5.

<Second Embodiment> FIG. 3 is a sectional view showing a cooling device according to a second embodiment of the present invention. In this embodiment, a plate-like lid 9 having good heat conductivity is arranged between the seal member 5 and the cold plate 6 of the cooling device in the embodiment shown in FIG. This is a configuration in which the plates 6 are joined. The package is sealed between the seal member 5 and the lid 9. Therefore, the package alone is up to the lid 9, and the cold plate 9 can be attached later. Other configurations are similar to those of the first embodiment shown in FIG.

The material of the lid 9 is, for example, a metal such as aluminum, or if the insulation with the semiconductor chip 4 is important, an insulating coating may be applied to the surface, or a ceramic such as aluminum nitride. But it's okay. Further, heat conductive grease may be applied between the cold plate 6 and the lid 9.

Also in this embodiment, when heat is generated in the semiconductor chip 4, this heat is transmitted to the lid 9 and the cold plate 6 through the liquid 8 in the cap 7 and cooled in the flow path 6a of the cold plate. By directly exchanging the medium, the semiconductor chips 4 can be cooled well.

<Third Embodiment> FIG. 4 is a sectional view showing a cooling device according to a third embodiment of the present invention. In this embodiment, fins 11 are provided instead of the cold plate 6 of the cooling device in the second embodiment shown in FIG. 3, and the lower portions of the fins 11 are formed in a flat plate shape so as to be in close contact with the lid 9. Has been done. The other structure is similar to that of the second embodiment shown in FIG.

Also in this embodiment, when heat is generated in the semiconductor chip 4, this heat is transferred to the lid 9 and the fins 11 via the liquid 8 in the cap 7. The heat transferred to the fins 11 is dissipated by the cooling air blown from a fan (not shown), so that each semiconductor chip 4 can be cooled well.

<Fourth Embodiment> FIG. 5 is a sectional view showing a cooling device according to a fourth embodiment of the present invention. In this embodiment, the liquid holding member 12 having the uneven portion 12a is bonded onto the semiconductor chip 4 of the cooling device in the second embodiment shown in FIG. 3, and the uneven portion 12a of the liquid holding member 12 in the cap 7 is insulated. The liquid 8 having the property is injected. A slight gap is formed between the lid 9 and the liquid holding member 12, and the liquid 8 is held in the gap between the liquid holding member 12 and the lid 9 by surface tension. And in the cap 7, H
A gas having a high thermal conductivity such as e (helium) is enclosed. The other structure is similar to that of the second embodiment shown in FIG.

As the material of the liquid holding member 12, for example, aluminum nitride, which has a high thermal conductivity and a thermal expansion coefficient close to that of the semiconductor chip 4, can be used.

Also in this embodiment, when heat is generated in the semiconductor chip 4, most of this heat is passed through the insulating liquid 8 injected into the uneven portions 12 of the liquid holding member 12 to cover the lid 9 and the cold plate 6. And the remaining heat is transferred to the cold plate 6 through a gas such as helium sealed in the cap 7 and is directly heat-exchanged by the cooling medium flowing in the flow path 6a of the cold plate 6. As a result, each semiconductor chip 4 can be cooled well.

Further, in the above-mentioned embodiment, the liquid 8 having the insulating property is injected into the concave-convex portion 12 of the liquid holding member 12, but the cap 7 on which the semiconductor chip 4 is arranged is arranged.
Instead of gas, the liquid 8 having an insulating property may be filled and filled.

<Fifth Embodiment> FIG. 6 is a sectional view showing a cooling device according to a fifth embodiment of the present invention. As shown in this figure, in the present embodiment, a plurality of semiconductor chips 4 each having a fin 21 connected to the upper portion via a pin 20 are mounted on a substrate 1, and a duct 22 is arranged above each fin 21. It is set up.

The duct 22 is composed of a duct main body 23 and a cylindrical nozzle 24, and one side surface of the duct main body 23 has an inlet port 23a for introducing the cooling air 25.
Are formed. The nozzles 24 are formed so as to project inside the duct body 23 and do not project outside the duct body 23. The nozzles 24 are located above the fins 21 attached to the semiconductor chips 4, respectively. ing.

The cooling device according to this embodiment is configured as described above, and when heat is generated in each semiconductor chip 4, this heat is transmitted to the fin 21.

The cooling air 25 blown from a fan (not shown) is introduced into the duct body 2 through the inlet 23a.
The semiconductor chip 4 can be cooled well by radiating the heat transferred to the fins 21 by the cooling air introduced into the nozzles 3 and blown from the nozzles 24 to the fins 21.

As described above, in this embodiment, since the nozzle 24 is provided in the duct body 23, the thickness of the duct body 23 can be reduced.

Further, in the above-mentioned embodiment, the nozzle 24 is not projected from the surface of the duct body 23, but it may be projected to some extent.

<Sixth Embodiment> FIG. 7 is a sectional view showing a cooling device according to a sixth embodiment of the present invention. In this embodiment, each nozzle 2 of the duct 22 in the fifth embodiment shown in FIG.
4 is an inlet 2 of the duct body 23 into which cooling air is introduced.
It is a configuration inclined to the 3a side. The other structure is similar to that of the fifth embodiment shown in FIG.

As described above, in this embodiment, the duct body 23
By inclining the nozzle 24 therein, the duct 22 can be further thinned to cool the semiconductor chip 4.

Further, since the cooling air is blown out from diagonally above the fins 21 by inclining the nozzles 24, it is not necessary to use the fins 21 for the collision jet as in this embodiment, and the air flows in from the side surfaces. Such a general fin may be used.

<Embodiment 7> FIG. 8 is a sectional view showing a cooling device according to a seventh embodiment of the present invention. In this embodiment, the nozzle 24 is configured by forming a semicircular protrusion 26 around the inside of the opening 23a formed on the fin 21 side of the duct body 23. The other structure is similar to that of the fifth embodiment shown in FIG.

Also in this embodiment, the duct 22 can be made thin to cool the semiconductor chip 4.

[0046]

As described above with reference to the embodiments, according to the invention described in claim 1, even if there are variations in height and inclination when mounting a plurality of heating elements on a substrate, The heat of the heating element can be satisfactorily transferred to the heat conductive plate for cooling, and the heat transfer structure is simplified by performing heat transfer via fluid, so the thickness can be made thin and compact. Can be promoted.

According to the present invention as defined in claim 2,
Since the nozzle for flowing the cooling air to the fin does not project to the outside, it is possible to reduce the thickness of the duct and achieve miniaturization.

[Brief description of drawings]

FIG. 1 is a sectional view showing a cooling device according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the cooling device shown in FIG.

FIG. 3 is a cross-sectional view showing a cooling device according to a second exemplary embodiment of the present invention.

FIG. 4 is a sectional view showing a cooling device according to a third exemplary embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a cooling device according to a fourth exemplary embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a cooling device according to a fifth exemplary embodiment of the present invention.

FIG. 7 is a cross-sectional view showing a cooling device according to a sixth exemplary embodiment of the present invention.

FIG. 8 is a sectional view showing a cooling device according to a seventh embodiment of the present invention.

FIG. 9 is a cross-sectional view showing an example of a conventional cooling device.

FIG. 10 is a cross-sectional view showing an example of a conventional cooling device.

[Explanation of symbols]

 1 Substrate 4 Semiconductor Chip 5 Sealing Member 6 Cold Plate 7 Cap 8 Liquid 9 Lid (Heat Conducting Plate) 11, 21 Fins 12 Liquid Holding Member 22 Duct 23 Duct Body 24 Nozzle 26 Projection

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Sudo 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Stock company Toshiba Research Institute

Claims (3)

[Claims] 1. A flexible seal member disposed on a peripheral surface of a substrate on which a heating element is mounted, and a heat conduction plate disposed on the sealing member so as to seal the heating element. A cooling device comprising an insulating fluid filled in a space surrounded by the substrate, the seal member and the heat conducting plate. 2. A duct comprising a fin connected to a heating element, a duct main body for introducing cooling air, and a nozzle formed so as to protrude inside the duct main body and having nozzles for flowing the cooling air to the fin. A cooling device characterized by the above. 3. The heat conducting plate also serves as a cooling means for cooling the heating element, or further comprises cooling means for cooling the heating element by cooling the heat conducting plate. The cooling device according to claim 1, wherein the cooling device is configured as follows.