JPH0322704B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cooling structure having a cooling plate for cooling electronic components such as semiconductor elements in electronic equipment, and particularly relates to a cooling structure having a cooling plate formed of a flexible heat transfer member. The present invention relates to a cooling structure formed such that the electronic component is pressed against the cooling plate through the sheet.

In recent years, electronic components such as semiconductor elements mounted on printed circuit boards used in the construction of electronic devices have become increasingly densely packaged and processed at high speeds, and the amount of heat generated by these electronic components tends to increase. be.

Therefore, in order to obtain stable operation, a major issue is how to efficiently remove such calorific value.

For cooling such electronic components, as an economical cooling device that can obtain a high cooling effect,
2. Description of the Related Art Cooling devices are generally known in which heat generated by electronic components is absorbed by a cooling plate through which a coolant such as cold water is circulated.

Such a cooling device is constructed as shown in the perspective view of FIG.

Printed circuit board 1 on which multiple electronic components 2 are mounted
The cooling plates 3 are provided so as to be stacked on each other, and the surface of the electronic component 2 is brought into pressure contact with a predetermined surface of the cooling plate 3. Cooling is achieved by circulating cold water through the pipes.

In such a cooling device, in order to improve the cooling efficiency of the electronic components 2, the surfaces of the electronic components 2 are formed on predetermined surfaces of the cooling plate 3 so as to be uniform and to obtain good heat transfer. It is important that

[Conventional technology]

Conventionally, the configuration was as shown in the side view of FIG. 3a.

One surface of a sheet 5 formed of a flexible member is engaged with a convex portion 4 formed on the cooling plate 3, and the other surface is configured to be in close contact with the surface of the electronic component 2.

The convex portion 5 is formed into a quadrilateral 4A or a circular shape 4B depending on the heat transfer surface of the electronic component 2, for example, as shown in the perspective views b1 and b2 of FIG.

Further, the outer shape of the sheet 5 is also formed in the same manner as the convex portion 4, and the convex portion 5 is formed so as to uniformly adhere to the surface of the electronic component 2 due to the elasticity of the sheet 5.

Therefore, consideration is given to absorbing variations in the machining accuracy of the convex portions 4 or the height of the heat transfer surface of the electronic component 2 by the sheet 5, thereby ensuring good heat transfer.

[Problem that the invention seeks to solve]

Such a sheet 5 is fixed to the convex portion 4 with an adhesive or a bonding material 6 such as double-sided adhesive tape, as shown in the main part side views of c1 and c2 in FIG. 3, and misalignment may occur. It is locked so that it does not.

In the case of c1, this adhesion is performed by applying the bonding material 6 to the surface of the convex portion, so that air remains in the central portion A at the time of adhesion, creating bubbles.

Furthermore, in this case, the bonding material is interposed in the heat conduction path, resulting in a reduction in heat transfer.

Further, in the case of C2, as described above, the bonding material 6 is applied to the outer circumferential portion to prevent the generation of air bubbles, so that no air remains in the central portion A. However, in this case, due to pressure contact, an air layer is formed in portion B near where the bonding material 6 is applied.

Therefore, in either case, there is a problem in that heat transfer is reduced due to air layers such as bubbles.

[Means for solving problems]

The above-mentioned problem is caused by a convex surface formed at a predetermined location of the cooling plate through which refrigerant is circulated, an electronic component mounted on a printed circuit board, and a flexible heat transfer member, and a bonding material is applied to the convex surface. a cooling structure in which the surface of the electronic component is pressed into contact with the convex surface via the sheet, the convex surface having a groove portion on the outer periphery thereof to serve as an adhesion margin for the bonding material. The problem is solved by the cooling structure according to the present invention, which is formed so that the bonding material is disposed intermittently in the grooves.

[Operation] That is, a groove is formed on the outer periphery of the convex surface formed at a predetermined location of the cooling plate, and a groove is formed in the groove (adhesion margin) intermittently so that the bonding material is scattered. It was originally formed.

This can prevent the formation of air layers such as bubbles between the sheet and the convex surface as in the conventional case, and can achieve good adhesion and improve heat transfer.

〔Example〕

The present invention will be explained in detail below with reference to an embodiment shown in FIG. a is a side view of the main part, b is an explanatory diagram, c1,
c2 is a plan view. Note that the same reference numerals indicate the same objects throughout the figures.

As shown in FIG. 1a, a groove 4A serving as an adhesive margin is provided on the outer periphery of the convex portion 4, and the sheet 5 is fixed to the convex portion 4 by filling the groove 4A with a bonding material 6. The rest of the configuration is the same as above.

As shown in FIG.
By applying pressure and filling the groove 4A with a bonding material 6 such as an adhesive, the surface 4B of the convex portion 4 and the sheet 5 can be brought into perfect contact with each other without flowing into the space between the surface 4B of the convex portion 4 and the sheet 5.

Furthermore, as shown in c1 and c2 in Fig. 1, the filling of the bonding material 6 is not carried out all over the groove 4A of the convex part, but intermittently in both the case of the quadrilateral c1 and the circular c2. It is important to do so.

With this configuration, no air remains between the surface 4B and the sheet 5 during adhesion.

In addition, more effective heat transfer can be obtained by locating the groove 4A on the outer periphery of the heat transfer surface to which the electronic component 2 is in close contact.

Furthermore, such a sheet 5 may be removed due to damage such as scratches, and in this case, conventionally, removing the sheet requires rubbing the surface 4B, damaging the surface 4B, but with this configuration, the groove 4A is removed. There is an advantage that the bonding material can be removed and the surface 4B will not be damaged.

〔Effect of the invention〕

As explained above, in the present invention, a groove is provided on the outer periphery of the convex portion to serve as an adhesive margin, and the groove is intermittently filled with a bonding material to fix the sheet.

This avoids the formation of an air layer between the sheet and the convex surface as in the past, and achieves good contact for heat transfer, improving cooling efficiency and cooling efficiency, which has a great practical effect. be.

[Brief explanation of the drawing]

In FIG. 1, a is a side view of the main part of one embodiment of the present invention;
b is an explanatory diagram, c1 and c2 are a plan view, Fig. 2 is a perspective view of the cooling device, Fig. 3 is a conventional diagram, a is a side view, and b
1 and b2 are perspective views, and c1 and c2 are side views of main parts. In the figure, 1 is a printed circuit board, 2 is an electronic component, 3 is a cooling plate, 4 is a convex portion, 5 is a sheet, 6 is a bonding material, and 7 is a plate.

Claims (1)

[Scope of Claims] 1. A convex surface formed at a predetermined location of a cooling plate through which refrigerant is circulated, an electronic component mounted on a printed circuit board, and a flexible heat transfer member, which is bonded to the convex surface. a cooling structure in which the surface of the electronic component is pressed into contact with the convex surface via the sheet, the cooling structure comprising a sheet fixed to the convex surface by a material, and a groove portion on the outer periphery of the convex surface to serve as an adhesion margin for the bonding material. A cooling structure characterized in that the groove portion is provided with the bonding material intermittently scattered therein.