JPH0515307B2 - - Google Patents

Description

[Detailed Description of the Invention] [Summary] The cooling efficiency of the refrigerant is improved by fixing fins that form a circulation path through which a refrigerant circulates to a semiconductor element, and a magnetic seal is attached to the outer periphery of the fins. By providing this, it is formed so that it can be easily inserted into and removed from the cooling plate.

[Industrial application field]

The present invention relates to a cooling structure that cools a semiconductor element such as an LSI element mounted on a printed circuit board by circulating a coolant, and in particular, the present invention relates to a cooling structure that cools a semiconductor element such as an LSI element mounted on a printed circuit board by circulating a coolant. The present invention relates to a cooling structure for semiconductor elements formed so as to improve cooling efficiency using a refrigerant.

Semiconductor devices such as LSI devices, which are widely used in electronic devices, have recently become more densely packaged and faster, and electronic devices configured with a large number of these semiconductor devices are unstable. In order to achieve high performance, a cooling device is used to forcibly cool each semiconductor element.

Cooling efficiency is high for this kind of cooling device,
Moreover, it is important to be economical and highly reliable, and a cooling device shown in FIG. 3 using a cooling plate in which a refrigerant is generally circulated is known.

FIG. 3 is a perspective view showing an outline of the cooling device.

As shown in FIG. 3, the cooling plate 3 is stacked on the printed circuit board 1 on which a plurality of semiconductor elements 2 are mounted, as shown by the arrow C.
is provided so that one cooling surface of the semiconductor element 2 is in close contact with the surface of the semiconductor element 2.

Therefore, the refrigerant flows through one opening 10 of the cooling plate 3.
It is circulated by being supplied from the other port 10 as shown by arrow A and discharged from the other port 10 as shown by arrow B.

Through this circulation, the heat generated by each semiconductor element 2 is cooled down.

Therefore, in such a cooling structure, it is desired that the thermal conductivity between the semiconductor element 2 and the cooling plate be good in order to further improve the cooling efficiency.

[Conventional technology]

Conventionally, the structure was as shown in the conventional side cross-sectional view of FIG.

As shown in FIG. 4, a heat transfer element 15 formed by fixing a flange 12 to one end of a bellows 13 made of an elastic material and a heat transfer plate 14 to the other end is attached to the cooling plate 3 using an O-ring. 17 so that the heat transfer plate 14 is brought into close contact with the surface 2A of the semiconductor element 2 by pressure in the direction of the arrow P through the thermal sheet 16 formed of a material with good thermal conductivity. It was composed of

Further, a nozzle 11 is provided in the flow path 3A of the cooling plate 3, and the refrigerant 4 is directed from the arrow F1 to the nozzle 1.
1 into the interior 13A of the bellows 13 as shown by the arrow F2, and is circulated by being discharged from the interior 13A as shown by the arrow F3.

In such a configuration, when the printed circuit board 1 is removed from the cooling plate 3 due to a failure of the semiconductor element 2, the thermal sheet 16 is sandwiched between the heat transfer plate 14 and the surface 2A of the semiconductor element 2. , the thermal sheet 16 is designed to be removed by cutting off the sandwiching portion thereof.

Therefore, the heat generated by the semiconductor element 2 mounted on the printed circuit board 1 is absorbed by the coolant 4 that is circulated through the thermal sheet 16 and the heat transfer plate 14 that are in close contact with the surface 2A.
Cooling is achieved by transferring heat to.

[Problem that the invention seeks to solve]

Therefore, in such a configuration, the thermal sheet 16 is formed of a soft material with good thermal conductivity,
The spring force of the bellows 13 improves the adhesion between the surface 2A and the heat transfer plate 14, so that efficient heat transfer is performed.

However, in reality, there has been a problem in that the heat transfer efficiency is reduced due to each contact surface with the thermal sheet 16, resulting in poor cooling efficiency.

It has also been considered to apply a paste-like heat transfer material instead of the thermal sheet 16;
When such a paste is applied, there is a problem in that the thickness of the applied film varies, making it impossible to obtain uniform cooling efficiency.

[Means for solving problems] FIG. 1 is a sectional view of the principle of the present invention.

As shown in FIG. 1, each of the semiconductor elements 2 is provided with a fin 5 forming a circulation path 5A for circulating a coolant 4, and the fin 5 is arranged so that the fin 5 can be inserted into and removed from the cooling plate 3. 5 outer peripheral part 5B
is shielded by a magnetic seal 6 having a magnetic fluid 6A.

With this configuration, the above-mentioned problems are solved.

[Effect]

That is, a circulation path through which a coolant circulates is formed in the fins fixed to the semiconductor element, and the semiconductor element is directly cooled by circulating the coolant through the circulation path using a cooling plate.

Further, the joint between the cooling plate and the fins is shielded by a magnetic seal so that they can be inserted into and removed from each other.

Therefore, unlike conventional methods, heat transfer is not performed through contact surfaces, and cooling is performed by the refrigerant flowing directly into the fin circulation path, improving thermal conductivity and improving cooling efficiency. can be achieved.

〔Example〕

The present invention will be explained in detail below with reference to FIG.
FIG. 2 is a side sectional view of an embodiment according to the present invention. The same reference numerals indicate the same objects throughout the figures.

As shown in FIG. 2, a magnet 7 and an N electrode 8A are connected to the cooling plate 3 via an O-ring 18.
A magnetic seal 6 consisting of a and an S electrode 8B is locked.

Further, the fins 5 having the refrigerant circulation path 5A inside are fixed to the surface of the semiconductor element 2 mounted on the printed circuit board 1 by welding, adhesion, or soldering, and the outer peripheral part 5B of the fin 5 is fixed to the surface of the semiconductor element 2 mounted on the printed circuit board 1. electrode 8A,
The magnetic fluid 6 held in each of the S electrode 8B
It is constructed so that it is shielded by A.

In this case, a ring 9 made of a soft magnetic material such as stainless steel is provided on the outer periphery 5B of the fin 5 where the magnetic fluid 6A comes into close contact with the S electrode 8B.
The magnetic fluid 6A is held by the magnetic field formed as shown by the dotted line in , and the magnetic fluid 6A is not attached to the ring 9 side when the fin 5 is inserted or removed by separating the printed circuit board 1 and the cooling plate 3. This is taken into consideration.

Therefore, the flow path 3A of the cooling plate 3 is indicated by the arrow F.
1 flows out from the nozzle 11 into the circulation path 5A as shown by the arrow F2, and from the circulation path 5A the refrigerant flows into the magnetic fluid 6 of the magnetic seal 6 as shown by the arrow F3.
By blocking A, it is distributed without leakage.

In this way, the refrigerant flows sequentially to the next circulation path 5.
It is designed to be circulated by being distributed to A.

Therefore, with this configuration, the fin 5
Since the refrigerant can be directly passed through the semiconductor element 2 and the contact portion E between the surface of the semiconductor element 2 and the fin 5 is fixed, the thermal conductivity is high and the cooling efficiency can be improved. .

In addition, when removing the printed circuit board 1 from the cooling plate 3 due to a failure of the semiconductor element 2, etc.,
By extracting the refrigerant from the flow path 3A and the circulation path 5A and inserting and removing the fins 5 from the magnetic seal 6, the printed circuit board 1 can be easily inserted and removed.

〔Effect of the invention〕

As described above, according to the present invention, the structure is such that a printed circuit board can be inserted and removed, and the refrigerant can be directly circulated through the fins.

Therefore, by improving the heat exchange efficiency using the refrigerant, it is possible to improve the cooling efficiency compared to the conventional method, and the practical effect is great.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the principle of the present invention, FIG. 2 is a side sectional view of an embodiment of the present invention, FIG. 3 is a perspective view of a cooling device, and FIG. 4 is a conventional side sectional view. In the figure, 1 is a printed circuit board, 2 is a semiconductor element, 3 is a cooling plate, 4 is a coolant, 5 is a fin,
6 is a magnetic seal, 5A is a circulation path, 5B is an outer peripheral part,
6A indicates a magnetic fluid.

Claims (1)

[Scope of Claims] 1. A cooling plate 3 through which a refrigerant 4 flows, a semiconductor element 2 mounted on a printed circuit board 1, and a fin 5 fixed to the semiconductor element 2.
is the circulation path 5A from the cooling plate 3 to the fin 5.
This is a cooling structure for a semiconductor element in which the heat generated by the semiconductor element 2 is cooled by circulating the coolant 4, and the joint between the cooling plate 3 through which the coolant 4 is circulated and the opening of the fin 5 is magnetic. A magnetic seal 6 in which the magnetic fluid 6A is formed on the outer peripheral portion 5B of the fin 5 so as to be shielded by the fluid 6A.
A cooling structure for a semiconductor device, characterized in that the cooling plate 3 is provided with: