JPH02129950A - Resin-sealed semiconductor device - Google Patents

Abstract

PURPOSE:To absorb thermal expansion efficiently by a method wherein a vessel having an aperture is placed on the surface of soft resin so as to make the aperture side face the soft resin while an air gap is provided in the aperture. CONSTITUTION:An aperture is provided in a vessel 22. The vessel 22 is placed on the surface of soft resin 18 so as to make the aperture face the soft resin 18 while an air gap 23 is provided in the aperture. Even if the soft resin 18 is expanded by heat, therefore, the thermal expansion is absorbed by the inner air gap 23 of the vessel 22. For that purpose, the vessel 22 can be placed at the position where the thermal expansion of the soft resin 18 can be absorbed most efficiently. With this constitution, the thermal expansion can be absorbed efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a composite semiconductor device, and particularly to a resin-sealed semiconductor device.

(Conventional technology) FIG. 2 is a sectional view of a conventional semiconductor device.

In the conventional semiconductor device shown in FIG. 2, a case 12 is mounted on a substrate 11 made of copper. An insulating substrate 13 is provided on the surface of the substrate 11 inside the substrate 11 and the case 12. One end of an L-shaped terminal 14.14 is fixed to each of both sides of the upper surface of the insulating substrate 13.

The other end of terminal 14.14 extends upwardly. Insulating substrate 1
A terminal 15 is fixed at the center of the upper surface of 3. Semiconductor chips 16 and 16 are bonded to one end of the terminal 14 on the left side in the figure and to the top of the terminal 15, respectively. The semiconductor chip 16 on the left side in the figure and the terminal 15 are connected by a wire 17 made of aluminum.

One end of the terminal 14 on the right side in the figure and the semiconductor chip 16 on the terminal 15 are wires 1 made of aluminum as well.
7 is connected.

After the above-mentioned parts are assembled inside the substrate 11 and the case 12 in this way, the inside of the case 12 is filled with a flexible resin 18 such as silicone gel. As a result, the semiconductor chip 16 is surrounded by the flexible resin 18. Furthermore, the inside of this case 12 is filled with a thermosetting resin 19 such as epoxy resin. As a result, the surface of the flexible resin 18 is covered with the thermosetting resin 19.

(Problems to be Solved by the Invention) In the conventional semiconductor device having the above structure, the thermosetting resin 19 is directly attached to the semiconductor chip 16 or the wire 17.
If the components are sealed with resin, they may be damaged, so they are protected by being surrounded by flexible resin 18.

By the way, although the flexible resin 18 such as silicone gel has flexibility and is suitable for protecting the semiconductor chip 16 etc., its coefficient of thermal expansion is lower than that of the thermosetting resin 19 such as epoxy resin. Because it is much larger than
The following problems have been pointed out.

That is, the semiconductor chip 16.14 is connected via the terminals 14.14.
When power is applied to 16 to activate them, the semiconductor chip 1
6.16 rises in temperature, the temperature of the entire inside of the case 12 rises accordingly, and as a result, not only the flexible resin 18 surrounding it, but also the thermosetting resin 19 covering the surface of the flexible resin 18. It will thermally expand. In this thermal expansion, the flexible resin 18 is better than the thermosetting resin 1.
9, the flexible resin 18 thermally expands more than the thermosetting resin 19. Therefore, a large internal pressure is applied to the thermosetting resin 19 from the flexible resin 18, and as a result, a force is applied to the terminal 14, 14 to lift it upward.

When such a force acts on the terminal 14.14 due to repeated energization of the semiconductor chip 16.16, the semiconductor chip 16.16, the wire 17, etc. are eventually connected to the terminal 14.1.
There is a problem in that the solder that connects and fixes the connection to 4 becomes fatigued, resulting in a poor connection.

FIG. 3 is a sectional view of a conventional semiconductor device designed to solve the above problem. In FIG. 3, parts and components that are the same or correspond to those in FIG. 2 are given the same reference numerals, and descriptions of the parts and parts with the same reference numerals will be omitted to avoid redundant explanation.

In the conventional semiconductor device shown in FIG.
．． Case 12
．． A gap 21.21 is formed between the inner wall of 12 and the inside of its protrusion 20.20.

In the semiconductor device shown in FIG. 3, even if the flexible resin 18 thermally expands, the voids 21 and 21 absorb the thermal expansion, so that the internal pressure is applied to the thermosetting resin 19 due to the thermal expansion of the flexible resin 18. I'm trying not to get it on.

However, in the semiconductor device shown in FIG.
．． Since the position of the protrusion 21 has to be on the periphery of the inner wall of the case 12.12, the effect of absorbing thermal expansion of the flexible resin 18 is inferior, and the protrusion 20 of the structure as shown in FIG.
．． There is a problem in that the cost of the mold for injection processing of 12.12 mm having 20 mm is high.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to make it possible to absorb the thermal expansion of a flexible resin sufficiently and effectively without the need for extra processing on the case.

(Means for Solving the Problem) In order to achieve such an object, in the semiconductor device of the present invention, a semiconductor chip is surrounded by a flexible resin,
In the case where the surface of the flexible resin is covered with a thermosetting resin, the opened container is placed on the flexible resin surface with the open side facing the flexible resin side and with a void inside. It is characterized by being placed on.

(Function) Since the container is placed with its opening side facing the surface of the flexible resin, even if the flexible resin thermally expands, the thermal expansion is absorbed by the internal voids of the container.

In this case, the container can be placed in a position that is more effective in absorbing the thermal expansion of the flexible resin, so that the thermal expansion can be absorbed more efficiently.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view of a semiconductor device according to an embodiment of the present invention. Portions and parts that are the same as or corresponding to those of the conventional example shown in FIGS. 2 and 3 are given the same reference numerals, and the same Descriptions of portions and parts related to reference numerals will be omitted to avoid redundant explanations.

The structure of the semiconductor device of this embodiment differs from that of the conventional example as follows.

That is, the semiconductor device of this embodiment includes an open container 22. The container 22 has its opening side facing the flexible resin 18 side, and is placed on the surface of the flexible resin 18 with a gap 23 existing inside the container 22.

The material of this container 22 may be the same as that of the case 12.12 or another material, and the number of containers 22 placed is one in this embodiment, but it is not necessarily one. Of course, there is no need for it, and it is also possible to have more than one.

In addition, by forming small holes 24 to the extent that the thermosetting resin 19 does not flow into the container 22, the voids 24 are formed when the flexible resin side 8 is cured or when the thermosetting resin 19 is cured.
3 may be made avoidable.

Since the other configurations are the same as those of the conventional example, the explanation thereof will be omitted.

Next, to explain the function, the container 22 is made of flexible resin 18.
Since it is placed on the surface of the container 22 with its open side facing, even if the flexible resin 8 thermally expands, the thermal expansion is absorbed by the internal void 23 of the container 22. In this case, it is possible to place the container 22 in the most effective position for absorbing the thermal expansion of the flexible resin 18, for example, the position shown in FIG. 1, so that the thermal expansion can be absorbed efficiently. You will be able to do that.

(Effects of the Invention) As is clear from the above explanation, according to the present invention,
Since the container was placed on the surface of the flexible resin with its opening side facing the flexible resin side and a void inside, when the flexible resin thermally expanded, the container's internal void would It can absorb thermal expansion. In this case, since the container can be placed at the most effective position for absorbing the thermal expansion of the flexible resin, the thermal expansion can be absorbed efficiently.

Therefore, according to the present invention, the thermal expansion of the flexible resin can be achieved without the need for extra processing on the case as in the conventional case, that is, without increasing the cost of the mold for the processing. It is possible to provide a structure that can absorb the substances effectively enough. As a result, even if the flexible resin thermally expands, the semiconductor chips surrounded by it will no longer cause poor connections with terminals, etc. due to the difference in thermal expansion between the flexible resin and the thermosetting resin. be done.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a semiconductor device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a semiconductor device according to a conventional example, and FIG. 3 is a cross-sectional view of a semiconductor device according to another conventional example. 14...Terminal, 15...Terminal, 16...Semiconductor chip, 17...Wire, 18...Flexible resin,
19... Thermosetting resin, 22... Container, 23...
Voids, 24... small holes. In the drawings, the same reference numerals do not indicate the same or corresponding parts.

Claims (1)

[Claims] (1) In a resin-sealed semiconductor device in which a semiconductor chip is surrounded by a flexible resin, and the surface of the flexible resin is covered with a thermosetting resin, an opened container is placed so that its opening side is covered with the flexible resin. 1. A resin-sealed semiconductor device, characterized in that the device is placed on the surface of a flexible resin with voids existing inside and facing the resin side.