JPH04139754A - Cooler - Google Patents

Abstract

PURPOSE:To reduce a thermal resistance by transferring heat generated from a heat generating element to a heat transfer block through a board, dissipating it by cooling means provided integrally with the block, and also transferring it to a cap through substance having high thermal conductivity sealed in the cap. CONSTITUTION:When heat is generated from a semiconductor chip 1, the heat is transferred from the bottom 3b to the side 3d of a heat transfer block 3 through a board 2, and dissipated from upper fins 3c. Part of the heat generated from the chip 1 is transferred to a cap 7 through helium gas. One type of heat pipe is formed with the cap 7 as a heat source and with the fins 3c as a cool source, and the heat of the cap 7 is dissipated to the fins 3c through substitute chlorofluorocarbon. Thus, even if many wiring pins for electric connection are provided on the back of the board 2, the heat generated from the chip 1 can be effectively transferred to the fins 3c of cooling means by reducing thermal resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a cooling device used for cooling a heat generating element such as a semiconductor chip.

(Prior Art) Heat-generating elements such as semiconductor chips generate heat during operation, so they are cooled by a cooling device in order to maintain performance.

FIG. 3 is a sectional view showing an example of a conventional semiconductor chip cooling device. As shown in this figure, a semiconductor chip 10
1 is disposed in a space formed by a substrate 102 and a package 103, and is connected to the substrate 102 via a bump or bonding wire (not shown). Further, a fin 104 is connected to the back surface of the substrate 102.

The conventional cooling device is configured as described above, and when heat is generated in the semiconductor chip 101, this heat is transferred to the fins 104 via the substrate 102.

The heat transferred to the fins 104 is dissipated by cooling the package using a fan or the like, thereby cooling the semiconductor chip 101.

(Problem to be Solved by the Invention) Recently, a large number of wiring bins for electrical connections have been taken out from the back of the board 102, so it is necessary to install fins 104 as a cooling means on the back of the board 102. It is no longer possible to simply install it as before. For this reason, the cooling effect of the semiconductor chip 101 decreases due to the increase in thermal resistance, and there is a fear that the performance of the semiconductor chip 101 may not be maintained.

The present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention to provide a cooling device that can reduce thermal resistance and efficiently transfer heat to a cooling means.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above-mentioned problems, the cooling device according to the present invention includes a heat transfer block that is integrally provided with a cooling means and has a space inside. , a substrate having a heat generating element attached thereto which is thermally connected to an inner wall surface of the space formed in the heat transfer block, and a cap tightly attached to the substrate so as to surround the heat generating element, It is characterized in that a substance that is a good thermal conductor is sealed in the cap, and a refrigerant is sealed in the space formed in the heat transfer block.

(Function) According to the present invention, the heat emitted from the heat generating element is transferred to the heat transfer block via the substrate, and is further radiated by the cooling means provided integrally with the heat transfer block.

In addition, the heat emitted from the heating element is transferred to the gear 1. Further, the heat transferred to the cap is transmitted to a cooling means integrally provided in the heat transfer block via a refrigerant sealed in a space formed in the heat transfer block, and is radiated.

(Example) Hereinafter, the present invention will be explained in detail based on the illustrated example.

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

As shown in this figure, a substrate 2 on which a plurality of semiconductor chips 1, which are heating elements, are attached is connected to an inner wall surface 3a at the bottom of a space 4 formed in a heat transfer block 3.

A plurality of wiring bins 5 connected to the substrate 2 penetrate through the bottom surface 3b of the heat transfer block 3 to which the substrate 2 is connected and are taken out to the outside. It is connected to a wiring board 6 disposed below the bottom surface 3b of. In addition, fins 3 are provided on the top of the heat transfer block 3.
C is formed.

A cap 7 made of a good thermal conductor is tightly attached to the substrate 2 so as to airtightly surround the semiconductor chip 1.
The cap 7 is filled with helium gas, which has electrical insulation (not limited to cases where the semiconductor chip 1 is a module or the like and does not require electrical insulation) and is a good thermal conductor. . Further, a fluorocarbon substitute is sealed as a refrigerant around the substrate 2 and the cap 7 in the space 4 formed in the heat transfer block 3.

The cooling device according to the present invention is configured as described above,
When heat is generated by the semiconductor chip, this heat is transmitted from the bottom surface 3b of the heat transfer block 3 to the side surface 3d through the substrate 2,
Heat is radiated from the upper fins 3c.

Further, a part of the heat emitted from the semiconductor chip 1 is transmitted to the cap 7 via helium gas.

A type of heat pipe is formed in which the cap 7 is a heat source and the fins 3c are a cooling source, so that the heat of the cap 7 is transmitted to the fins 3C via the fluorocarbon substitute and is radiated.

In this way, in this embodiment, even if a large number of wiring bins 5 for electrical connections are provided on the back surface of the board 2, the heat emitted from the semiconductor chip 1 is efficiently absorbed by the fins, which are cooling means, by reducing the thermal resistance. It can be conveyed to 3c.

Moreover, since the wiring bin 5 penetrates the bottom surface 3b of the heat transfer block 3 and is connected to the wiring board 6 provided below the bottom surface 3b, cooling can be performed while maintaining electrical insulation. .

FIG. 2 is a sectional view showing a cooling device according to another embodiment of the present invention.

In this embodiment, the space 4 formed in the heat transfer block 3 is
A copper rod 8 is connected between the inner upper wall surface 4b and a cap 7 surrounding the semiconductor chip 1, and the other structures and functions are the same as those of the embodiment described above.

In this way, in this embodiment, a part of the heat transferred to the cap 7 is transferred to the fins 3C via the copper rod 8 and is dissipated, so that heat conduction can be carried out more efficiently than in the above-mentioned embodiments, and the effect is Thus, the semiconductor chip 1 can be cooled down.

[Effects of the Invention] As described above in detail based on the embodiments, according to the present invention, the heat emitted from the heating element is transmitted to the cooling means integrally provided in the heat transfer block via the substrate. At the same time, a part of the heat emitted from the heating element is transferred to a cap that is sealed with a good thermal conductor and is attached to surround the heating element.Furthermore, the heat transferred to the cap is transferred to a heat transfer block. The heat is transmitted to the cooling means integrally provided in the heat transfer block via the coolant sealed in the space formed in the heat transfer block, and is radiated. Therefore, the thermal resistance is reduced and heat can be efficiently transferred to the cooling means, so that the heating element can be effectively cooled.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a cooling device according to the present invention, FIG. 2 is a cross-sectional view showing a cooling device according to another embodiment of the present invention,
FIG. 3 is a sectional view showing a conventional cooling device. 1... Semiconductor chip (heating element) 2... Substrate 3... Heat transfer block 3a... Inner wall surface 3b... Bottom surface 3C... Fin (cooling means) 4... Space 5...・Wiring pin 6...Wiring board 7...Cap 8...Copper rod

Claims (2)

[Claims] (1) A heat transfer block in which a cooling means is integrally provided and a space is formed inside, and a heating element that is thermally connected to the inner wall surface of the space formed in the heat transfer block is attached. It comprises a substrate and a cap tightly attached to the substrate so as to surround the heat generating element, a material that is a good thermal conductor is sealed in the cap, and a refrigerant is introduced into the space formed in the heat transfer block. A cooling device characterized by being sealed. (2) Wiring pins are taken out to the outside by penetrating the surface of the heat transfer block to which the substrate is connected, and the wiring pins are connected to a wiring board arranged outside the heat transfer block. The cooling device according to claim 1.