JPS606090B2 - Manufacturing method of semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for attaching a semiconductor element to a substrate for a semiconductor device.

A conventional structure for attaching a semiconductor element to a semiconductor device substrate will be described using a resin-sealed semiconductor device lead frame.

First, Au plating is applied to a portion (hereinafter referred to as an island) on which a semiconductor element of a lead frame made of a metal material such as Kovar is placed. This lead frame is heated to a temperature at which the Au-Sj alloy piece can be melted (approximately 3800°C).
0 or more), then bring the Airan-Japanese semiconductor device with the Au-Si alloy piece on it and rub it back and forth and left and right (hereinafter referred to as scrubbing). An alloying reaction occurs with the Au plated portion. As a result, the semiconductor element can be firmly bonded to the island. Even if a semiconductor element is scrubbed on the Au plating directly applied to Kovar without using an Au-Si alloy piece, the Au-Si alloying reaction occurs, resulting in the same result as described above. The bonding method using the Au--Si alloying reaction described above is also effective in manufacturing hermetically sealed semiconductor devices whose substrates are made of ceramic or metal materials, and is widely used.

However, when scrubbing a lead frame, the lead frame itself must be prepared at the work site, which is often troublesome and does not make manufacturing easier.

The same holds true for hermetically sealed semiconductor devices whose base bodies are made of ceramic or metal materials. or,
In the conventional technology, heat dissipation is determined by the material and thickness of the lead frame or the ceramic material forming the entire container, so it is difficult to design with heat dissipation as important.

Therefore, an object of the present application is to provide a method for manufacturing a semiconductor device that is easy to manufacture and has good heat dissipation.

The features of the present invention include the step of fixing the semiconductor element to the upper surface of the support with an adhesive, and then inserting the semiconductor element into a through hole provided in the base for a semiconductor device, and then attaching the semiconductor element to the bottom of the base and the support. fixing a portion of the upper surface of the body where the semiconductor element is not provided with an adhesive, and the side wall of the through hole and the side wall of the semiconductor element are set to be 0.5 side or less. The present invention provides a method for manufacturing a semiconductor device, in which the semiconductor element is positioned at a predetermined location on the base by using a method of manufacturing the semiconductor device. In the prior art, there is a structure in which a recess is provided in a base and a semiconductor element is adhered to the bottom surface of the recess.

However, when scrubbing with this structure, the semiconductor element is pinched with tweezers or other tools, so in order to obtain good adhesion, the semiconductor element and the island must be spaced at least 1. Requires a gap of 0.5 ribs or more when divided into equal parts. Some semiconductor devices are so large that even the above-mentioned gap cannot be removed, making it impossible to perform sufficient scrubbing. As a result, if the alloying reaction does not proceed sufficiently, the semiconductor element will peel off from the island due to a slight external force.
Furthermore, if the alloying reaction proceeds non-uniformly, it promotes the generation of non-uniform thermal stress, leading to frequent failures such as cracks in semiconductor devices. Further, in order to perform sufficient scrubbing with the above-mentioned conventional technique, a large recess is required, which results in a large container as a whole. In contrast, with the structure of the present invention, the semiconductor element can be freely scrubbed and reliably fixed to the support.

In addition, in the present invention, "the gap between the through hole and the semiconductor element is reduced to 0".
．． Preferably, there are no more than five legs. This is because the mounting position of the semiconductor element within the island in the bonding process, that is, on the substrate for semiconductor devices, can be kept constant for practical purposes, and this reduces the alignment time in the currently widely used wire bonding process. This is because it is possible to shorten. This time saving effect is remarkable when automatic machines are used. Even when assembling a semiconductor device with two or more semiconductor elements on one island, the positions of the semiconductor elements can be kept constant, making assembly reliable and easy to automate assembly. can do. Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a first embodiment of the present invention applied to a resin-sealed semiconductor device.
An example is shown below. That is, FIG. 1 shows a first embodiment of the present invention in which a support 5, which is to become a part of an island, is provided on a surface of a semiconductor element 2 that does not include an active castle. The semiconductor element 2 is bonded onto a support 5 made of a metal material such as Kovar or a ceramic material metallized with alumina, beryllia, etc. and whose surface is plated with Au. As the adhesive material, Au--Si, Au--Sn brazing material, etc. can be used. A support 5 on which a semiconductor element 2 is layered is installed so that the semiconductor element 2 is inserted into a through hole of an island of a base ribbon, and the island shell and support 5 are bonded. The island part of the base ribbon made of Kovar is A
U-plated. Adhesive material is Au-Si, Au-Sn
Brazing wood is effective. By providing the support 5, it is possible not only to strengthen the adhesion to the island, but also to significantly reduce the thermal resistance of the semiconductor device.Next, it is possible to significantly reduce the thermal resistance of the semiconductor device. A second embodiment of the present invention applied to is shown in FIG.

A semiconductor element 2 is bonded to a support 5 made of a ceramic material that has been metallized and plated with Au. A for adhesive
U-Si alloy brazing material is used. The outer green 6 of the through hole of the base island is metallized and Au plated. The support 5 on which the semiconductor element 2 is spread is installed so that the semiconductor element 2 is inserted into the through hole through the Au-Sn brazing material ring 3b, and is bonded by pressing and heating. The part 3a directly below the element is made of an Au-Si alloy, and the area around the through hole is made of an Au-Sn alloy.
Since the melting point of the Au-Si alloy is about 100q0 higher than that of the Au-Sn alloy, the adhesive 3a will not melt when heated during the formation of the adhesive 3b. After the semiconductor element 2 is fixed to the semiconductor device substrate as described above,
After predetermined wire bonding is performed according to a conventional assembly process, a ceramic cap is used for sealing with Au-Sn brazing material.

By using the above assembly method, it is possible to prevent defects such as cracks occurring in the semiconductor element or peeling of the semiconductor element from the island due to a slight external force. First of all,
Although the second embodiment has been described, the above embodiment is only a part of the embodiments of the present invention, and it is a matter of course that it does not limit the scope of the claims of the present invention.

[Brief explanation of the drawing]

The drawings all show embodiments of the present invention; FIG. 1 is a cutaway front view of essential parts of the first embodiment, and FIG. 2 is a cutaway front view of the entire device of the second embodiment. Regarding the drawings, 1 is the base island, 2 is the semiconductor element, 3 is the adhesive, 5 is the support, and 6 is the green outside of the through hole of the base.

Claims (1)

[Claims] 1. A step of fixing the semiconductor element to the upper surface of the support with an adhesive, and then inserting the semiconductor element into a through hole provided in the base for semiconductor device, and aligning the bottom surface of the base with the upper surface of the support. and fixing the part where the semiconductor element is not provided with an adhesive, and the side wall of the through hole and the side wall of the semiconductor element are set to be 0.5 mm or less, so that the substrate 1. A method for manufacturing a semiconductor device, characterized in that the semiconductor element is positioned at a predetermined location.