JPH0362957A - Heat-pipe accommodating type mounting board - Google Patents

Abstract

PURPOSE:To provide uniform, sufficient heat radiation property by providing a plurality of hole parts along the entire length of an element mounting surface, converting the hole parts into heat pipes, inserting heat pipe containers into the specified hole parts of said hole parts, forming heat pipes, making the heat pipes extrude from the side surface of the board, and obtaining heat radiating parts. CONSTITUTION:Elements 1 such as ICs and LSIs are mounted on a board 2 wherein a flat plate which comprises aluminum, copper and the like and has excellent heat conductivity is used for the material of the board. A plurality of hole parts 3 are provided in the side surface of the board 2 along the entire length of the element mounting surface. Actuating liquid is sealed in the hole parts, and heat pipes are formed. Heat pipe containers 4 as the other bodies comprising aluminum, copper and the like are inserted into the specified hole parts of said hole parts, e.g. at the rate of 5:1-2:1. The containers are made to be heat pipes. The heat pipes are made to extrude from the side surface of the board. Said parts are made to be heat radiating parts 7. Thus, the heat-pipe accommodating type mounting board is obtained. Namely, the soaking of the board is provided by the heat pipes which are densely arranged in the board. The temperature approaches the uniform temperature as a whole.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a mounting board for ICs, LSIs, etc., and it is possible to efficiently radiate heat generated from elements such as ICs, LSIs, etc. by using a heat pipe. The present invention relates to a mounting board with a built-in heat pipe.

[Prior art and its issues] In the electronics field, substrates on which ICs, LSIs, etc. are mounted are becoming increasingly denser due to the demands of the era of lighter, thinner, shorter, and smaller sizes. Volume is increasing.

Furthermore, the amount of heat generated by the element itself is large, making countermeasures for heat dissipation an important issue.

These heat radiation methods include heat sinks made of metal such as aluminum, forced air cooling, methods using refrigerants, and methods using heat pipes.

However, heat sinks made of metal such as aluminum may not be able to dissipate heat completely, so forced air cooling or using refrigerants may
As the equipment becomes larger and more complex, noise from other fans and the like becomes a problem, which increases costs.

In the case of heat pipes, there are two methods: attaching the heat pipe directly to one element to dissipate heat, and embedding the heat pipe in the board, but the former only increases the heat dissipation area of one element. It is difficult to standardize the design,
It has a strong implication that it is a temporary emergency measure. Regarding the latter, uneven heat dissipation occurs between the heat pipe part and other parts of the board, making it impossible to equalize the temperature of the entire board, resulting in a lack of heat dissipation from the entire system, and heat dissipation is a problem, especially in high-density packaging. It becomes.

[Problem to be solved by the invention]

The present invention was made as a result of studies on the above-mentioned problems, and has developed a mounting board with a built-in heat pipe that eliminates the unevenness of heat dissipation in parts of the board and has uniform and sufficient heat dissipation over the entire board. It is something.

[Means and effects for solving the problems] The present invention uses a thermally conductive flat plate as a substrate material, provides a plurality of perforations on the side surface of the flat plate over the entire length of the element mounting surface, and converts the perforations into heat pipes. In addition, the heat pipe built-in mounting board is characterized in that a heat pipe container is inserted into a predetermined perforation part of the perforation part to form a heat pipe, and the heat pipe is made to protrude from the side surface of the board to serve as a heat dissipation part.

That is, the present invention can be applied to IC, L as shown in FIG. 1, for example.
A plurality of perforations (3) are provided along the entire length of the element mounting surface on the side surface of the substrate (2), which is made of a flat plate with good thermal conductivity such as aluminum or copper, on which elements (1) such as SI are mounted. A working fluid is sealed in the perforated part to form a heat pipe, and a predetermined perforated part of the perforated part (for example, one in five
Aluminum is used for the perforation part, which is one in two or one in two.
A separate heat pipe container (4) made of copper or the like is inserted to form a heat pipe, and this heat pipe is made to protrude from the side surface of the board, and this part is used as a heat dissipation part to form a heat pipe built-in mounting board.

Figure 2 shows a mounting board with a built-in heat pipe assembled as described above.A hole is drilled in the side of the aluminum board (2) on which an IC or other element (1) is mounted, and both ends are sealed. A heat pipe (5) (5') that is made into a heat pipe by filling a hole and sealing a working fluid, and a heat pipe that is made into a heat pipe by inserting a separate heat pipe container into a predetermined hole of the hole. (6) and (6') are built into the board. and heat pipes (6), (6'
) are used as heat radiating parts (7), (7'), and fins are attached thereto to radiate heat.

According to the above structure, the heat pipes arranged densely inside the board uniformize the temperature of the board, bringing the temperature of the board as a whole close to -, and then the heat is led out of the board by an independent heat pipe. This is to effectively dissipate heat while averaging the heat of the entire board. Therefore, it is possible to freely mount elements at any position on the substrate.

However, the above heat pipes (5), (5'), (6)
, (6'), etc., an independent heat pipe (6') etc.
), (6') should be provided at a ratio of 1 in every 2 to 1 in every 5. If the number is higher than this, the heat dissipation part will become too dense.
Moreover, if the amount is less than this, the heat dissipation effect will be reduced.

In addition, in order to further improve heat uniformity, as shown in Figure 3, the heat pipes (5), (5') and the independent heat pipes (6), (6') are provided with communication holes (8), (8'). ), and by making the respective heat pipes communicate with each other, it is possible to improve the heat uniformity in the lateral direction and further improve the heat uniformity as a whole.

Note that the heat pipe built-in mounting board of the present invention can be manufactured by various methods such as welding and casting in addition to being created by machining.

In addition, as means for cooling the heat dissipation section, the above-mentioned fins may be attached, and in addition to air cooling such as natural cooling or a fan, a cooling device such as water cooling or cooling using a refrigerant may be attached. Furthermore, miniaturization is possible by using a micro heat pipe as the heat pipe.

〔Example〕

An embodiment of the present invention will be described below.

As shown in Figure 1, l 50mX 150rmS thickness 3
A flat plate made of aluminum of IIIm is used as the substrate (2),
Fifty 2ffI11 square perforations (3) were formed through the side surface of this substrate. Four out of five of these perforations were made into heat pipes as they were, and a copper heat pipe container (4) of 2 mm square and 250 m5 in length was inserted into one of the five perforations. This was made into a heat pipe, and an IC element was mounted on it to create a mounting board with a built-in heat pipe as shown in Fig. 2 (two out of five pieces shown).

This board was found to have better heat uniformity over the entire board compared to a conventional board with embedded heat pipes.

[Effects] As described above, according to the present invention, a heat pipe-embedded mounting board with excellent heat uniformity and heat dissipation properties can be obtained, and it has an industrially significant effect.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a method for producing a mounting board with a built-in heat pipe according to the present invention, FIG. 2 is a perspective view of a main part of a mounting board with a built-in heat pipe according to the present invention, and FIG. FIG. 2 is a plan view of a heat pipe built-in mounting board according to an example. DESCRIPTION OF SYMBOLS 1...Element, 2...Substrate, 3...Perforation part,
4... Heat pipe container, 5.5', 6.6'
...Heat pipe, 7,7'...Heat radiation part, 8,
8'...Communication hole.

Claims (3)

[Claims] (1) A thermally conductive flat plate is used as a substrate material, a plurality of perforations are provided on the side surface of the board over the entire length of the element mounting surface, the perforations are made into heat pipes, and predetermined perforations of the perforations are made into heat pipes. Insert a heat pipe container to make it into a heat pipe,
A mounting board with a built-in heat pipe, characterized in that the heat pipe protrudes from a side surface of the board to serve as a heat dissipation section. (2) The heat pipe built-in mounting board according to claim 1, wherein the perforations in the board communicate with each other through communication holes. (3) The heat pipe built-in mounting board according to claim 1 or 2, characterized in that a fin is provided in the heat dissipation section.