JPH07202083A - Semiconductor module - Google Patents

Abstract

(57) [Abstract] [Purpose] A semiconductor module used in small and lightweight electronic devices that is easy to assemble, does not require a space for heat dissipation, and has a significantly improved heat dissipation capability, and a semiconductor that generates a large amount of heat. The purpose is to be able to mount. [Structure] One side of a U-shaped spring 4 is fixed to the upper surface of the CPU 3, and the other side is in contact with a metal casing 5. The heat generated by the CPU 3 is radiated to the housing 5 via the U-shaped spring 4, and the housing 5 can be used as a large area heat dissipation plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CPU used in small and lightweight electronic devices such as portable personal computers and word processors.
The present invention relates to a semiconductor module that generates a lot of heat.

[0002]

2. Description of the Related Art CPUs used in small and lightweight electronic devices
Such semiconductors generate heat when they operate, and if they do not properly dissipate heat, the heat generated by themselves may cause unstable operation.

The following is a description of conventional measures for heat dissipation of a semiconductor module in a small and lightweight electronic device. FIG. 3 is a cross-sectional view of a semiconductor module having a conventional heat sink and a plan view seen from above. In FIG. 3, reference numeral 11 denotes a semiconductor, which generates heat when operated. A heat dissipation plate 12 made of metal such as aluminum is provided on the upper surface of the semiconductor 11. The heat dissipation plate 12 is used when there is not much space above the semiconductor 11.

4 and 5 are a cross-sectional view and a plan view from above of a semiconductor module having a conventional radiation fin having a protrusion. In FIG. 4, reference numeral 13 is a radiating fin having comb-shaped protrusions, which is provided on the upper surface of the semiconductor 11. In FIG. 5, reference numeral 14 is a heat radiation fin having wart-shaped projections, which is provided on the upper surface of the semiconductor 11. The radiating fins 13 to 14 having these protrusions are used for the semiconductor 1
Used when some space can be secured above 1.

The heat dissipation plate 12 and the heat dissipation fin 13 as described above
When Nos. 14 to 14 are used, the heat dissipation surface area is increased and heat is released to the surrounding space, so that the semiconductor 11 can be cooled. In addition, the heat dissipation plate 12 and the heat dissipation fins 13 to 14
In order to improve the cooling efficiency by the method, the air passage of natural convection is secured as much as possible so that the air flow occurs near the heat dissipation plate 12 and the heat dissipation fins 13 to 14.

[0006]

However, the above-mentioned conventional semiconductor module is provided with a heat dissipation plate or a heat dissipation fin for heat dissipation of the semiconductor. However, as the size of electronic equipment advances, the heat dissipation plate and the heat dissipation plate are required due to space limitations. Large radiating fins could not be used, and the radiating surface area could not be increased. Of course, the fan that artificially creates the air flow cannot be installed in a small electronic device because it becomes quite large, and it was difficult to even secure a natural convection air flow path. For this reason, there has been a problem that as the size of electronic equipment advances, it becomes impossible to ensure sufficient heat dissipation capability of the semiconductor module.

Furthermore, in order to improve the performance of electronic equipment such as a portable personal computer, it is necessary to mount a high-performance CPU, but generally, the higher the performance of the CPU, the larger the amount of heat generation. For this reason, even if a high-performance CPU is mounted, the heat generation of the CPU is large and the heat dissipation capability of the semiconductor module cannot keep up, so that there is a problem that a CPU with large heat generation cannot be mounted.

The present invention solves the above-mentioned problems of the prior art, does not require a large space for heat dissipation, greatly improves the heat dissipation capability, can mount a semiconductor with a large amount of heat generation, and is easy to assemble. An object of the present invention is to provide a semiconductor module.

[0009]

In order to achieve the above object, the semiconductor module of the present invention focuses on a large metal plate part such as a back plate of a keyboard originally provided in an electronic device or a metal housing. Then, a semiconductor that generates heat when operating, a metal member that is arranged so as to face the upper surface of the semiconductor, and a material having a thermal conductivity of 100 W / m ° C. or higher, and one surface on the upper surface of the semiconductor. Is fixed, and the other surface is in contact with the metal member, and is constituted by urging means for constantly urging in the direction of the metal member.

[0010]

According to the semiconductor module of the present invention, the biasing means made of a material having a high thermal conductivity is brought into contact with a large-area metal member originally included in the electronic device to bias the heat generated by the semiconductor. The heat can be dissipated by being transmitted to the metal member via. That is, since a large area metal member originally provided in the electronic device can be used as a heat dissipation plate having a large heat dissipation surface area, the heat dissipation effect is very large.

[0011]

【Example】

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a semiconductor module used in a portable pen input type personal computer according to a first embodiment of the present invention.

In FIG. 1, 1 is a main board,
A CPU board 2 is detachably connected to the main board 1 via a connector. This CPU board 2
A CPU 3 that generates a large amount of heat is mounted on the upper surface of the. One surface of the U-shaped spring 4 is bonded to the upper surface of the CPU 3. The U-shaped spring 4 is made of a material having a high thermal conductivity, and is electroless nickel plated for corrosion resistance. A large-area casing 5 made of magnesium alloy is attached so as to press the U-shaped spring 4 from above, and the other surface of the U-shaped spring 4 contacts the casing 5.

A description will be given of heat dissipation measures of the semiconductor module configured as described above. The heat generated by the CPU 3 is transferred to the U-shaped spring 4 made of a material having a high thermal conductivity by bringing the U-shaped spring 4 made of a material having a large thermal conductivity into contact with the large-area housing 5 originally provided in the portable pen input type personal computer. The heat can be transferred to the housing 5 via the heat sink 4.

Here, in the case where a CPU having a heat generation amount of 1.7 W was used in the semiconductor module of this embodiment, the surface temperature of the CPU 3 was measured under the following conditions. The measurement conditions are as follows: when the heat dissipation measures are not taken without using the U-shaped spring 4, when a conventional heat sink having a thickness of 0.5 mm is used instead of the U-shaped spring 4, and when the thickness is 0. This is a case where the thermal conductivity was changed by using a U-shaped spring 4 of 5 mm, and the results are shown in comparison with (Table 1).

[0015]

[Table 1]

Unless the surface temperature of the CPU of this embodiment is 85 ° C. or lower, the operation becomes unstable. To meet this condition, use a conventional heat sink having a larger area than the measurement results shown in (Table 1) or use a U-shaped spring 4 made of a material having a thermal conductivity of about 100 W / m ° C or more. There is only one case where heat is radiated to the housing 5. However, a large area heat sink is
It is not possible to attach it to U with a portable pen input type personal computer with a small space. Therefore, if copper (386 W / m ° C.) having a high thermal conductivity is used as the material of the U-shaped spring 4 of this embodiment, a sufficient heat dissipation effect can be obtained without requiring a large space. Since the thermal conductivity of copper decreases as the amount of impurities increases, copper having a purity of 99% or more is used as a U-shaped spring in this embodiment.

Further, in the semiconductor module of this embodiment, when the power consumption of the CPU is changed, the result of measuring the temperature of the upper surface of the CPU 3 is shown in comparison with (Table 2).

[0018]

[Table 2]

From the measurement results shown in (Table 2), it has been confirmed that the conventional pen-input type personal computer is 1.0 W due to the problem of heat generation.
Although it was possible to mount only a CPU of the order of magnitude, it became possible to mount a CPU having a high heat generation of about 2.5 W by using the semiconductor module of this embodiment.

There is also a method of completely fixing the CPU 3 to the housing 5 with screws or the like. In this case, the CPU 3
It is necessary to previously provide holes for screwing in the CPU board 2 on which the CPU is mounted and the housing 5, and tightly fix the CPU 3 and the housing 5 by screwing them together during assembly, which makes the assembly very difficult. On the other hand, in the semiconductor module of this embodiment, since the U-shaped spring 4 is only brought into contact with the housing 5,
Easy to assemble.

As described above, in the semiconductor module of this embodiment, the heat generated by the CPU 3 is radiated to the housing 5 via the U-shaped spring 4, and the housing 5 can be used as a large area heat dissipation plate. A space for heat dissipation is not required, the heat dissipation capability is greatly improved, a CPU with high heat generation can be mounted, and the assembly can be easily performed.

Although the U-shaped spring 4 is used in the above embodiment, an O-shaped spring may be used as long as it has a large contact area with both the CPU 3 and the housing 5.

The material for the U-shaped spring 4 has a purity of 9
Although 9% or more of copper is used, the purity of copper may be less than 99%, and any material having a large thermal conductivity such as aluminum, silver, gold, or magnesium alloy may be used in addition to copper.

Further, in order to enhance the heat radiation effect of the CPU 3, the CPU 3 may be resin-sealed into an SQFP package, or the CPU 3 may be covered with a ceramic 7 to form a ceramic package.

Further, although the above embodiment is applied to the portable pen input type personal computer, it is an information processing equipment such as a small personal computer or a word processor having a high heat generating CPU, or an electronic device having a high heat generating element such as an amplifier or a power source. It can also be applied to equipment.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a sectional view of a semiconductor module used in a notebook computer according to the second embodiment of the present invention.

In FIG. 2, 1 is a main board,
A CPU board 2 is detachably connected to the main board 1 via a connector. This CPU board 2
A CPU 3 that generates a large amount of heat is mounted on the upper surface of the. One surface of the U-shaped spring 4 is bonded to the upper surface of the CPU 3. The back plate 6 of the keyboard is composed of a large-area metal plate such as tin plate or aluminum, and is attached so as to press the U-shaped spring 4 from above, and the other surface of the U-shaped spring 4 is attached. Contacts the back plate 6 of the keyboard.

Heat dissipation measures of the semiconductor module configured as described above will be described. The U-shaped spring 4 made of a material having a high thermal conductivity is brought into contact with the large-sized back plate 6 originally provided in the notebook computer, so that CP
The heat generated by U3 can be transferred to the back plate 6 through the U-shaped spring 4 and radiated.

[0029]

As described above, according to the semiconductor module of the present invention, the heat generated by the semiconductor is radiated to the large area metal member originally provided in the electronic device through the biasing means, and the metal member has a large area. Since it is used as a heat radiating plate, it does not require a large space for heat radiating, the heat radiating ability can be greatly improved, a semiconductor having a large heat generation can be mounted, and it can be easily assembled.

[Brief description of drawings]

FIG. 1 is a sectional view of a semiconductor module used in a portable pen input type personal computer according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a semiconductor module used in a notebook computer according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view and a plan view of a semiconductor module having a conventional heat sink.

FIG. 4 is a cross-sectional view and a plan view of a semiconductor module including a conventional radiation fin having a comb-shaped protrusion.

FIG. 5 is a cross-sectional view and a plan view of a semiconductor module including a conventional radiation fin having wart-shaped protrusions.

[Explanation of symbols]

 1 Main board 2 CPU board 3 CPU 4 U-shaped spring 5 Housing 6 Keyboard back plate

Claims (3)

[Claims] 1. A semiconductor that generates heat when operating, a metal member that is disposed so as to face the upper surface of the semiconductor, and a material having a thermal conductivity of 100 W / m ° C. or higher, and one of which is formed on the upper surface of the semiconductor. Of the semiconductor module is fixed, and the other surface is in contact with the metal plate and is always urged in the direction of the metal plate. 2. The semiconductor module according to claim 1, wherein a U-shaped spring is used as the biasing means. 3. The semiconductor module according to claim 1, wherein copper is used as the biasing means.