JPS63284837A - Cooling structure of semiconductor element - Google Patents

Abstract

PURPOSE:To simplify a process and to perform effective cooling, by sealing a fluorine group coolant in a package and concurrently performing airtight sealing of the package. CONSTITUTION:A fluorine group coolant is hermetically sealed on a reduced pressure state in a structural body formed by mounting a cap airtightly on a package. For example, a semiconductor element 1 is connected with wiring electrodes housed in an inner room 3A of the package 3, through a brazing material 2. The package 3 and the cap 5 are coupled airtightly through the brazing material to be formed unitedly. A fluorine group coolant 4 with a boiling point of 102-253 deg.C, comparatively high, is sealed on a reduced pressure state in the inner room 3A of the package 3. If the coolant with the boiling point of 102-253 deg.C is sealed in a container just at the boiling point, the sealed-in coolant is supercooled at a room temperature after its hermetical sealing process and so pressure in the container is reduced. Since the boiling point of the coolant is also lowered and hence said coolant is easily vaporized by heat generation in an integrated circuit element, effective cooling can be performed by the use of heat of evaporation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cooling structure for a semiconductor element housed in a structure formed by airtightly coupling a package and a cap.

[Conventional technology]

Conventionally, regarding the cooling structure of a multi-chip/seven-chip assembly that mounts a large number of integrated circuit elements, for example, Japanese Patent Laid-Open No. 61-1
The method described in Japanese Patent No. 31553 has been proposed. The proposal proposes that one boiling point of 50-
A 60°C refrigerant is used.

[Problem that the invention seeks to solve]

In the conventional example described above, since a refrigerant with a boiling point of 50 to 60° C. is used, two steps are required: a step of sealing the cold 1ilfC in a container and a step of sealing the container. This not only complicates the manufacturing process, but also requires a great deal of time and effort, leading to a decrease in efficiency.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cooling structure for a semiconductor device that can simultaneously seal a refrigerant in a container and seal the container, and achieve effective cooling using the refrigerant.

[Means for solving problems]

The above problem is solved when a fluorine-based refrigerant having a relatively high boiling point of 102 to 253°C is sealed in the valley container under reduced pressure, and at the same time, the F container is sealed with a brazing material that melts at the boiling point. It will be solved by engineering.

[Effect]

When a refrigerant with a boiling point of 102 to 253° C. is sealed in a container at the same boiling point, the sealed refrigerant becomes supercooled at room temperature after being sealed, so that the pressure inside the container decreases.

Therefore, since the boiling point of the refrigerant is also lowered, the refrigerant is easily vaporized by the heat generated by the integrated circuit element, and effective cooling is performed by the heat of vaporization.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, an integrated circuit element (semiconductor element) 1 is connected to a wiring IE pole (not shown) housed in an inner chamber 3A of a package 5 via a brazing material 2. The package 3 and the cap 5 are integrally and airtightly connected through 6 feet of brazing material.

A heat radiator 7 is attached to the cap 5.

The inner chamber 3AK of the package 5 is 1 in a reduced pressure state.
A fluorine-based refrigerant 4 having a relatively high boiling point of 02 to 256° C. is sealed. In the space above the refrigerant 4 in the inner chamber 3A,
It is full of refrigerant vapor 8.

Further, the brazing filler metal 6 is made of a material that melts at the boiling point of the fluorine-based refrigerant 4.

Since the refrigerant 4 that comes into direct contact with the semiconductor element 1 also comes into contact with the electrical wiring of the element 1, high insulation is required.

By the way, the fluorine-based refrigerant 4 having the boiling point has a volume resistance of 1
0 ohPom or more, dielectric strength is 25℃, 154r
Since r1m (gap) is 55 KV or more, this requirement can be satisfied.

Furthermore, since electrical signals flow through the electrical wiring section of the semiconductor element 1, it is required that the dielectric constant be small even in a high frequency range and that the propagation time should not be affected.

By the way, since the fluorine-based refrigerant has a dielectric constant of 2 or less even at 25° C. and IGH2, it can fully satisfy this requirement.

In the above-described embodiment, the heat generated in the semiconductor element 1 is conducted to the seven-wire cooling system 4 in contact with the periphery of the element 1. At this time, since the pressure inside the inner chamber 5A of the package 5 is reduced, the refrigerant 4 is easily vaporized. The semiconductor element 1 is cooled by this heat of vaporization, and the vaporized refrigerant vapor 8 is cooled and liquefied by the cap 5 and the radiator 7.

FIG. 2 is a cross-sectional view showing an intermediate process when attaching the cap 5 to the package 3 in an airtight manner.

The same reference numerals in the figure as in FIG. 1 indicate the same parts.

In FIG. 2, a semiconductor element 1 is connected to a wiring section [(not shown) of a package 3 via a brazing material 2, and a cap 5 equipped with a heat sink 7 is mounted on the package 3. There is.

When the refrigerant vapor 8 sealed in the package 3 is charged into the refrigerant vapor boiling from room temperature while maintaining the state MMt as described above, the refrigerant vapor 8 sealed in the package 3 is condensed due to the heat capacity of the package 5, cap 5, radiator 7, etc. Then, it becomes a refrigerant 4 and accumulates inside the package 5. If this state is maintained further, the brazing material 6
As a result, the package 5 is hermetically sealed by the cap 5. Therefore, by removing the package 3 and cap 5 from the refrigerant vapor, the structure according to this embodiment shown in FIG. 1 is obtained.

〔Effect of the invention〕

As explained above, according to the present invention, the manufacturing process can be simplified by enclosing it in a predetermined 7-layer cold package having a relatively high boiling point and at the same time sealing the package airtight. At the same time, effective cooling can be realized efficiently.

[Brief explanation of drawings]

11 is a cross-sectional view showing an embodiment of the cooling structure for a semiconductor element of the present invention, and FIG. 2 is a cross-sectional view showing an intermediate state of airtight sealing of the package in this embodiment. Explanation of symbols 1...Integrated circuit element, 2.6...Brazing material, 5...Package, 4...7-thread cold construction, 5 ······cap,

Claims (1)

[Claims] 1. In a structure in which a cap is airtightly attached to a package containing a wiring board on which a large number of integrated circuit elements are mounted, a cap is airtightly attached via a brazing material. A cooling structure for a semiconductor device, characterized in that a fluorine-based refrigerant having a relatively high boiling point is sealed therein. 2. The brazing material is made of a material that melts at the boiling point of the fluorine-based refrigerant, and the melting of the brazing material and the encapsulation of the refrigerant are performed simultaneously.
A cooling structure for a semiconductor device as described in Section 1.