JPH05160308A - Semiconductor chip module - Google Patents

Abstract

PURPOSE:To provide a semiconductor chip module which has such a structure that external shock is not given directly to a heat sink. CONSTITUTION:This module is equipped with a board 2 where a wiring part is provided, a semiconductor chip 7 which is mounted with is circuit face directed toward the wiring part, a heat sink 3 one part of which is in contact with the opposite face to the circuit face of this semiconductor chip 7, a cap 4 in a hole 4 for exposing the other end of this heat sink 3 to outside is made and which envelops the semiconductor chip 7, and a protective fence 5 which envelops the other end of the heat sink 3 exposed from this chip 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor chip module applicable to fields requiring high speed signal processing in computers and communications.

[0002]

2. Description of the Related Art As electronic equipment has become faster and more multifunctional, integrated circuits used in electronic circuits of these equipment have become faster and faster.
Higher density is progressing. As a result, the amount of heat generated per unit area of the integrated circuit also increases, and it has become necessary to consider the heat dissipation of the electronic circuit in order to maintain the performance of the device. The first method of heat dissipation is to dissipate heat from the board on which the components are mounted. However, as the performance of the integrated circuit has improved, the amount of heat generated has increased, and it has become impossible to dissipate sufficient heat only from the substrate. Therefore, it has become necessary to dissipate heat through a heat dissipation path other than this. For this reason, as a second method of heat dissipation, conventionally, the following 10
The method described on pages 22-1031 has been proposed.

(IEEE TRANSACTIONS OF COMPONENTS, HYBR
IDS. AND MANUCFACTURING TECHNOLOGY, VOL.13, NO.4, DEC
EMBER 1990).

The above document discloses a method in which a heat sink protruding from the semiconductor chip module is provided on the side opposite to the substrate and the heat sink is brought into contact with the integrated circuit.

[0005]

However, as in the above-described conventional semiconductor chip module, in the structure in which the heat sink protruding from the cap of the module is provided, the following problems occur. In other words, when some impact is applied to the protruding heat sink, the heat sink and the integrated circuit bonded to the lower portion of the heat sink are highly likely to be damaged.

An object of the present invention is to solve the above problems and to provide a semiconductor chip module having a structure in which an external impact is not directly applied to the heat sink.

[0007]

In order to achieve the above object, in a semiconductor chip module according to the present invention, a substrate on which a wiring portion is formed, a semiconductor chip mounted on the wiring portion with its circuit surface facing, A heat sink whose one end is in contact with the surface opposite to the circuit surface of the semiconductor chip, a cap which includes a semiconductor chip having a hole for exposing the other end of the heat sink to the outside, and a heat sink exposed from the cap. A module was configured with a protective cover including the end portion.

The protective cover is made of a net-like hard metal material.

[0009]

According to the semiconductor chip module of the present invention, the external impact is buffered by the protective cover and does not directly act on the heat sink.

Further, when the protective cover is made of a net-like hard metal material, the heat radiated from the heat sink is immediately released to the outside of the protective cover.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the attached FIGS. In the description of each of these drawings, the same reference numerals are used for the same elements, and duplicate description will be omitted. FIG. 1 is a perspective view showing the appearance of a multi-chip module as an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of the multi-chip module according to the embodiment taken along a heat sink.

The multi-chip module according to this embodiment comprises a lower substrate 1, an upper substrate 2, a heat sink 3, a cap 4 and a protective fence 5. The lower substrate 1 is made of an alumina material (AlN), and a plurality of lead pins 8 connected to the electric circuit constituted by the upper substrate 2 extend from the side surface of the lower substrate 1. The upper substrate 2 is made of a low dielectric constant insulating material, and has a thermal resistance of 3 ° C./W,
A 3-inch square polyimide multilayer wiring structure that also uses a thermal via can be used (see “Copper-polyimide multilayer wiring board”, HYBRIDS, Vol.7, No.1, pp.10-12).

The lower substrate 1 is composed of a flat plate larger than the upper substrate 2, and the upper substrate 2 is fixed in a stacked state on the upper surface thereof. Lower substrate 1 where upper substrate 2 does not overlap
The edge of the cap 4 is covered on the upper surface of the.
Therefore, the upper substrate 2 is contained by the cap 4 and the lower substrate 1.

Electrodes are exposed on the surface of the upper substrate 2, and semiconductor chips 6 and 7 connected to these electrodes are mounted. The semiconductor chips 6 and 7 are, for example, 10 mm
It is a square IC chip and is connected to the electrodes formed on the surface of the upper substrate 2 by a wire bonding method or a flip chip mounting method. In FIGS. 1 and 2,
The semiconductor chip 6 is mounted by the wire bonding method I
A C chip is shown, and a semiconductor chip 7 is an IC chip mounted by a flip chip mounting method. Therefore, the circuit surface of the semiconductor chip 6 faces the cap 4 and the semiconductor chip 7
The circuit side of the substrate faces the upper substrate 2.

The cap 4 is formed, for example, in the shape of a lid with a thickness of 1 mm of kovar, and is provided at a position corresponding to the mounting position of the semiconductor chip 7 which generates a relatively large amount of heat.
For example, a hole 4a having an inner diameter of about 6 to 8 mm is formed.
One end of the heat sink 3 is inserted into this hole 4a.

The heat sink 3 is made of a material (A
1, CuW, AlN, CBN, diamond, etc.) and is composed of an insertion part and a heat dissipation part. The insertion portion has a shape that facilitates insertion into the hole 4a described above, and has, for example, a rod shape. Further, since the heat radiating portion is exposed to the outside of the cap 4, it has a structure having a large surface area so as to be easily cooled naturally, and has a disk shape, for example.
The lowermost disc surface near the insertion portion of the heat radiating portion is an adhesion surface with the cap 4. Since the heat sink 3 is configured as described above, it is easy to insert the heat sink 3 into the inside of the cap 4, it is easy to make contact with the upper surface of the semiconductor chip 7, and the semiconductor chip 7 is placed outside the cap 4.
The heat from can be efficiently dissipated. Since the contact between the heat sink 3 and the semiconductor chip 7 is preferably surface contact, when the upper surface of the semiconductor chip 7 is a flat surface, it is desirable that the tip of the heat sink 3 is a flat surface rather than a curved surface.

Next, the mounting structure of the protective fence 5 of the heat sink 3 will be described. FIG. 3 is a partially enlarged cross-sectional view showing an enlarged heat dissipation portion of the heat sink 3 protruding above the cap 4. As shown in the figure, the protective fence 5 has a rectangular parallelepiped shape that covers the entire heat sink 3, and has a structure in which only one of the six surfaces of this rectangular parallelepiped that contacts the cap 4 is removed. The size of the protective fence 5 is 1 to 2 cm higher than the highest heat sink 3 in order to buffer the impact from the outside, and the width thereof is larger than that of the outermost heat sink 3. It is 1-2 cm larger. Further, the protective fence 5 is formed of a mesh-like hard stainless metal having a mesh of about 5 mm so as not to impair the heat radiation efficiency of the heat sink 3. The protective fence 5 and the cap 4 are fixed to each other by folding the marginal portion of the protective fence 5 into the module and adhering the folded portion to the cap 4 so that the fixed portion does not hinder the handling of the module. ..

In such a semiconductor chip module according to this embodiment, since the protective fence 5 covers the entire heat sink 3 protruding from the cap 4, the impact applied to the module from the outside is buffered and the heat sink 3 and this heat sink 3 are absorbed. The possibility of damaging the semiconductor chip 7 in contact with 3 is extremely reduced. Further, since the protective fence 5 is formed in a mesh shape, the heat radiation efficiency of the heat sink 3 is not hindered even if the protective fence 5 is provided.

[0019]

Since the present invention is constructed as described above, the external impact applied to the module is buffered by the protective cover and does not directly apply to the heat sink. Therefore, the possibility that the heat sink and the integrated circuit contacting the heat sink will be damaged by an external impact is extremely low.

When the protective cover is made of a net-like hard metal material, the heat radiated from the heat sink is quickly released to the outside of the protective cover. Therefore, it is possible to prevent the heat dissipation of the heat sink from being lowered by providing the protective cover.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of a multi-chip module according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a multi-chip module according to an embodiment of the present invention cut along a heat sink.

FIG. 3 is a partially enlarged cross-sectional view of a heat sink portion in a multi-chip module according to an embodiment of the present invention.

[Explanation of symbols]

1 ... Lower substrate, 2 ... Upper substrate, 3 ... Heat sink, 4 ...
Cap, 5 ... Protective fence, 6, 7 ... Semiconductor chip, 8 ... Lead pin

Claims (2)

[Claims] 1. A substrate on which a wiring portion is formed, a semiconductor chip mounted on the wiring portion with its circuit surface facing, and a heat sink whose one end is in contact with the surface of the semiconductor chip opposite to the circuit surface, It is configured by including a cap having a hole for exposing the other end of the heat sink to the outside and encapsulating the semiconductor chip, and a protective cover encapsulating the other end of the heat sink exposed from the cap. And semiconductor chip module. 2. The semiconductor chip module according to claim 1, wherein the protective cover is made of a net-like hard metal material.