JPH04245700A - Metal base board device - Google Patents

Abstract

PURPOSE:To improve the heat dissipation property and electromagnetic shield property of a metal board device having a high degree of integration. CONSTITUTION:A projected part of a metal base 1 comes into direct contact with the bottom of a semiconductor 4 and dissipates heat by way of the metal base through heat conduction. A V-shaped groove 6 is installed to a metal base board and the board is folded. The folded metal base board is fitted into a groove 9 of a U-shaped metal plate 7 which comprises the side and the bottom, thereby shaping a box which is enclosed and electromagnetically-shielded. Since the box body is formed by fitting and folding, automatic assembling is easy to be carried out, so that both heat dissipation effect and electromagnetic shield effect can be produced.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal-based substrate device that has both a heat dissipation effect for semiconductor elements that generate significant heat and a shielding effect for electronic components that leak electromagnetic waves.

0002

[Background Art] In recent years, as information devices have become more multifunctional,
The degree of integration of circuit boards is increasing. Furthermore, the frequency band used has expanded, and metal-based substrates are often used in consideration of electromagnetic shielding and heat resistance between the substrates.

A conventional shield for a metal base board prevents leakage of electromagnetic waves by attaching a shield case 13 to a metal part protruding from an end 16 of a metal base board 11 with screws 15, as shown in FIG. It has a structure.

0004

[Problems to be Solved by the Invention] However, in such a conventional configuration, the components 14 cannot be mounted on both sides of the metal base board 11, so as the degree of integration increases, the mounting area increases, and it is necessary to prevent leakage of electromagnetic waves. In order to do this, a shield case 13 is required separately, and there is a problem in that a hole 17 for heat radiation must be made in the shield case 13.

Heat dissipation of the conventional metal base substrate 11 is performed exclusively by the shield case 13 and the metal portion. However, since no particular measures have been taken to dissipate heat from the semiconductor element 14, which generates a large amount of heat, it is necessary to make a large number of holes in the shield case 13. However, if the number of holes is increased, the shielding becomes incomplete, and if the holes are made smaller, heat radiation will be hindered.

Furthermore, screws 15 must be used to connect the shield case 13 and the metal base substrate 11, making it difficult to adapt to automation.

The present invention solves these problems by reducing the mounting volume of a metal base board, ensuring sufficient heat dissipation effect to cool semiconductor elements that generate significant heat, and eliminating the need for a shield case. The object of the present invention is to provide a metal-based substrate device that can prevent leakage of electromagnetic waves and can be automatically assembled.

[0008]

[Means for Solving the Problems] In order to solve this problem, the present invention provides that the metal base of the metal base substrate is in direct contact with the bottom surface of the semiconductor element which generates significant heat at the pattern surface, and that the metal base of the metal base substrate is in direct contact with the bottom surface of the semiconductor element which generates significant heat, By inserting it into a metal plate to form a box, the metal base board itself acts as a shield case to prevent leakage of electromagnetic waves.

[0009]

[Function] With this configuration, the metal base board is bent with the metal part outside after mounting the components, and the metal case is fitted to the sides and bottom to form a box body to prevent leakage of electromagnetic waves. Because of this, a high shielding effect can be obtained.

Furthermore, since the bottom surface of the semiconductor element, which generates a lot of heat, and the metal part of the metal base substrate are in direct contact and heat is transferred, the cooling efficiency is high and the heat dissipation effect is large.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A metal base substrate device according to an embodiment of the present invention will be described below with reference to the drawings.

The metal base substrate device of the present invention enables bending by providing two V-grooves 6 only in the metal portion 1 on the back side of the bent portion of the metal base substrate, as shown in FIG. Heat dissipation from the semiconductor element 4, which generates a lot of heat, is carried out by the convex part 3 of the metal layer of the metal base substrate directly contacting the bottom surface of the semiconductor element 4, which generates a lot of heat, thereby improving cooling efficiency.

Further, as shown in FIG. 2, the bent metal base substrate is inserted and bonded so as to fit into the groove 9 of the U-shaped metal plate 7 forming the side and bottom surfaces. This joining may be done by mechanical contact only, but if electrical connection is important, soldering is used. A U-shaped notch 8 is provided at the bottom so that the terminal 10 of the metal base board does not come into contact with it.

[0014] With this configuration, the metal base substrate and the metal plate 7 can be fixed without using screws, and can also be adapted to automatic assembly. Furthermore, the metal base substrate and the metal plate 7 form a box and reinforce each other, resulting in a highly rigid structure as a whole.

Furthermore, as shown in FIG. 3, the metal base board of the present invention allows electrical circuits to be made into cards for each function, so the lead terminals 10 for mounting the board can be inserted into another board or a mating connector. By doing so, it functions as a single module.

[0016]

[Effects of the Invention] As is clear from the description of the embodiments above, the metal base substrate of the present invention provides the following effects.

(1) Great cooling effect for semiconductor elements that generate significant heat and are mounted on a metal base substrate.

(2) The metal substrate itself becomes a part of the shield case to prevent leakage of electromagnetic waves.

(3) The connection between the metal substrate and the metal plate is simplified by fitting, making automatic production possible.

[0020] The above effects greatly contribute to high-density packaging by satisfying both the functions of heat dissipation effect and shielding effect, and making full use of the features of the metal base substrate that can be automatically assembled.

[Brief explanation of the drawing]

[Fig. 1] A sectional view of the main parts of a metal base substrate device according to an embodiment of the present invention.

[Figure 2] Exploded perspective view

[Figure 3] Perspective view

[Figure 4] Cross-sectional view of a conventional metal base board and case

[Explanation of symbols]

1 Metal layer 2 Wiring pattern layer 3 Convex portion of metal layer 4 Semiconductor element 5 Parts 6 V groove 7 Metal plate 8 Notch 9 groove 10 Terminal

Claims (2)

[Claims] 1. A component that generates heat and a component that emits electromagnetic waves are mounted on a wiring pattern layer of a metal base board consisting of a metal layer and a wiring pattern layer, and a component that generates heat and a component that emits electromagnetic waves are mounted at the positions of two V grooves provided in the metal layer. The U-shaped metal base board is bent into a U-shape, and the U-shaped metal base board is fitted into a U-shaped metal plate that has a notch at the bottom for passing the terminal portion of the metal base board, and a groove on the side for inserting the metal base board. A metal base board device that together forms a box. 2. The metal base substrate device according to claim 1, wherein a convex portion is provided on the metal layer so as to contact the bottom of the heat generating component.