JPH1115566A - Electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce heat resistance between a high heat generation density semiconductor element and a housing and to improve the efficiency of assembly workability by thermally connecting a part of the surface of may high heat generation density semiconductor elements and a part of the housing with one flexible conductor. SOLUTION: A part of the housing for housing the high heat generation density semiconductor elements is constituted of the member 3 having high flexibility and high thermal conductivity. The heat of the high heat generation density semiconductor elements 1 is transmitted to the flexible conductor 3 from the upper face of the high heat generation density semiconductor element 1 and it flows through the housings 2 at both ends. Then, it is discharged to peripheral air. The flexible conductor 3 can improve contract heat conductance between the high heat generation density semiconductor elements 1 and the flexible conductor 3 by making face pressure generated when it is brought into contact with the high heat generation density semiconductor element 1 is set to be high. Since the flexible conductor 3 is soft, it is made in close contact with the high heat generation density semiconductor element 1 along its shape. Thus, high contact thermal conductance is obtained and heat which the flexible conductor 3 receives from the high heat generation semiconductor elements 1 spreads to a face direction and is transmitted to the housing 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device, and more particularly to a portable electronic device.

[0002]

2. Description of the Related Art In recent years, as the operation speed of a laptop personal computer has been increased, the heat generation density of semiconductor elements used in the computer has been increasing year by year. Further, since the computer contains a compact desk, a floppy desk, a driving battery, and the like, the weight tends to be further increased.
In addition, since the proportion of the volume of the attached parts such as the compact disk and the like increases, the area occupied by the original semiconductor element for arithmetic processing decreases, and the heat generation density of the semiconductor element increases. As a conventional technique, it is described in JP-A-6-51868 "Portable electronic device".

[0003]

Conventionally, a method of transmitting heat from a high-density semiconductor element to a housing via a spring has been adopted.
The position of the spring had to be determined. Therefore, the assembling work was not easy.

SUMMARY OF THE INVENTION It is an object of the present invention to improve the efficiency of assembly work and to reduce the thermal resistance between a high-density heat-generating semiconductor element and a housing, which are disadvantages of the related art. Another object is to efficiently release the heat of the high heat density semiconductor device to the outside air.

[0005]

According to the present invention, a part of a housing for accommodating a semiconductor element having a high heat generation density is formed of a member having high flexibility and high thermal conductivity, and the member and the semiconductor element having a high heat generation density are provided. By contacting a part of the surface, heat of the high heat density semiconductor element is efficiently transmitted to the housing.

Further, a fin is made to function by attaching a highly flexible and high heat conductive member to the housing.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a high heat density semiconductor device 1.
Are arranged inside the housing 2. Such an arrangement of high heat density semiconductor elements is often used in recent portable personal computers. FIG. 2 is a sectional view taken along line AA of FIG.
Shown in

The upper surface of the housing 2 is made of a member having high flexibility and excellent heat conduction characteristics. The material of this member is graphite (graphite). Ordinary graphite is hard without flexibility, but the graphite used here is enhanced in flexibility by being formed into a porous material having a large number of small holes.

[0009] The thermal conductivity is 5 to 6 times higher than that of stainless steel in the plane direction. On the other hand, the heat conduction in the direction perpendicular to the surface depends on the surface pressure applied to graphite, and the surface pressure is 75%.
At 0 atm, the same thermal conductivity as in the plane direction can be obtained. Hereinafter, this member is referred to as a flexible conductor 3. 4 is a printed circuit board. The printed circuit board 4 is mounted on a stand 5 inside the housing 2. The high-heat-density semiconductor element 1 is provided on a printed circuit board 4. The height of the housing 2 is adjusted in advance so that the upper surface of the high heat density semiconductor element contacts the lower surface of the flexible conductor 3 attached to the housing 2.

Hereinafter, the operation of the present invention will be described.

The heat of the high-heat-density semiconductor element 1 is transmitted from the upper surface of the high-heat-density semiconductor element 1 to the flexible conductor 3 and flows to the housings 2 at both ends. Finally, the housing 2 is heated and radiated to the surrounding air. This flexible conductor 3
The contact heat conductance between the high heat generation density semiconductor element 1 and the flexible conductor 3 can be increased by increasing the surface pressure generated when the semiconductor element 1 comes into contact with the heat generation density semiconductor element 1. Further, since the flexible conductor 3 is soft, it adheres closely to the shape of the high heat density semiconductor element 1.

For this reason, a high contact thermal conductance is obtained. High heat density semiconductor element 1 to flexible conductor 3
Is spread in the plane direction and is transmitted to the housing 2. Since the housing 2 is formed of a high heat conductive material such as aluminum, heat is diffused throughout the housing 2. If there is a possibility that the flexible conductor 3 may be in electrical contact with the high heat density semiconductor element 1, the flexible conductor 3 is formed of an electrically insulating film.
, The short circuit between the high heat density semiconductor element 1 and the flexible conductor 3 can be prevented.

Finally, the heat of the housing 2 is released to the surrounding air by natural convection. As described above, since the heat of the high heat density semiconductor element 1 flows to the entire housing 2, the semiconductor element having a higher heat density than before can be operated.

The flexible conductor 3 has a density of 1 g.
/ Cc, the weight is reduced. This effect is also an advantage for portable personal computers.

FIG. 3 is a sectional view of another embodiment of the present invention.

The semiconductor elements for high-speed arithmetic processing used in recent personal computers can be replaced according to the arithmetic processing speed desired by the user. FIG. 3 shows a semiconductor element socket 6 arranged on a printed circuit board 4 so that the high heat density semiconductor element 1 can be easily replaced. As described above, the high heat density semiconductor can be easily attached and detached by the semiconductor element socket. As in FIG. 2, if the height of the housing 2 can be set in advance so that the high heat generation density semiconductor element 1 and the flexible conductor 3 can come into contact with each other, the heat of the high heat generation density semiconductor element 1 2 can be transmitted to the whole.

FIG. 4 is a sectional view of another embodiment of the present invention.

A feature of the present invention is that a guide plate 7 is attached to a surface facing the side surface of the housing 2, and the upper portion of the guide plate 7 is connected to the flexible conductor 3.

FIG. 5 is a side view as viewed from the side of FIG. The guide plate 7 has a vertically long hole.
Can slide up and down. This slide mechanism brings the high heat density semiconductor element 1 and the flexible conductor 3 into contact with each other,
This is convenient when adjusting the surface pressure created by the flexible conductor 3 and the high heat density semiconductor element 1. When the optimum surface pressure is achieved, the flexible conductor 3 can be fixed to the housing 2 by the stator 8.

FIG. 6 is a top view of another embodiment of the present invention viewed from above. FIG. 7 is a sectional view taken along line AA of FIG. The flexible conductor 3 is sandwiched between the high heat-density semiconductor elements 1 and the upper lid of the housing 2 which are provided on the printed circuit board 4 in a large number. 2 attached to the upper lid. Since the fins 9 are made of a porous graphite material, the fins 9 have a small density and can be reduced in weight. further,
Since the heat conduction is high, the fin efficiency can be increased.
Further, since this graphite has a high emissivity, it is possible to release heat to the surroundings as radiant heat. FIG.
The fin 9 is enlarged. Reference numeral 11 denotes a holding plate for attaching the fins 9 to the housing 2 collectively.

The heat of the high heat density semiconductor element 1 flows to the housing 2 via the flexible conductor 3. Part of the heat of the housing 2 is released to the surrounding air by natural convection, and the remaining heat is transmitted to the fins 9 and further released to the surrounding air.

The same effect can be obtained with the flexible conductor of the present invention by laminating a plurality of metal sheets having a foil thickness of about 100 μm.

[0023]

According to the present invention, it is possible to reduce the thermal resistance between the high-density heat-generating semiconductor element and the housing and to increase the efficiency of assembly work. Further, the heat of the semiconductor element having a high heat generation density can be efficiently released to the outside air.

[Brief description of the drawings]

FIG. 1 is a plan view of an electronic device according to an embodiment of the present invention as viewed from above.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a cross-sectional view of another example of the electronic device according to the present invention.

FIG. 4 is a sectional view of another example of the electronic device according to the present invention.

FIG. 5 is a side view of FIG. 4;

FIG. 6 is a plan view of another example of the electronic device according to the invention.

FIG. 7 is a sectional view taken along line BB of FIG. 6;

FIG. 8 is a partially enlarged view of FIG. 7;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... High heat density semiconductor element, 2 ... Case, 3 ... Flexible conductor, 4 ... Printed circuit board, 9 ... Fin.

Claims (1)

[Claims] An electronic device in which a large number of high heat density semiconductor elements are mounted on a printed circuit board in a housing, a part of a surface of the high heat density semiconductor element and a part of the housing.
An electronic device characterized in that a part of the electronic device is thermally connected by one flexible conductor 3.