JPS6122864B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in hermetically sealed packages for semiconductors or integrated circuits that require ultra-high reliability.

Conventionally, airtight packages used for integrated circuits have been made of plastic packages molded with polymeric resin (generally epoxy resin) or metal hermetic packages, and the headers and caps are welded by projection welding or seam welding. Construction work when using this polymeric resin material is relatively simple and inexpensive, but since the polymeric resin material has the property of permeating and absorbing moisture, it cannot be used in devices that require ultra-high reliability.
In addition, hermetic seals by production welding are easy and inexpensive to construct, and because a large instantaneous current flows through the contact area between the header and the cap, which are objects to be welded, semiconductors or integrated circuits may be adversely affected by the induced current. Cheap. Furthermore, if the welding area is large, welding is impossible, or even if welding is done, the contact area between the header and the cap tends to be uneven and weld grains are likely to be generated. If this welding is encapsulated in a package, the reliability of the semiconductor or integrated circuit device is likely to deteriorate. For this reason, the practical size of projection welding is limited to packages with a diameter of 15 mm or less. On the other hand, hermetic sealing using a seam welding machine requires two opposing electrodes to be in uniform contact at the same time, so it is possible to weld larger packages compared to when using a projection welding machine; Another disadvantage is that it can only be used in relatively small package cages with a simple rectangular shape, with a diameter of 30 mm or less in the case of a circle, and a side of 30 mm or less in the case of a rectangle.

Based on the above considerations, it is an object of the present invention to provide a method that is relatively inexpensive, is not limited by size, and is easy to use by controlling the welding trajectory not only for circular or rectangular welding shapes but also for packages with more complex shapes. To provide a hermetic seal package for an integrated circuit in which hermetic sealing work can be performed using a laser welding machine capable of welding.

The present invention will be explained in detail below with reference to the drawings.

FIG. 1 is a perspective view of a header according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view of FIG. 1, and FIG. 3 is a partially exploded perspective view of an embodiment of the present invention. In the figure, 1 is a base, and 2 is a glass that encloses the leads 3. Further, 4 is a base material from which the base 1 is made of a material such as Kovar, 5 is a base plating layer on this base material 4, and 6 is a gold-plated metal. As the base plating, nickel plating, which has no optical selection, is generally used. Furthermore, 7 is an integrated circuit board, 8 is a brazing material, 9 is a thin gold wire, and 10 is a can (container case). Also,
Can 10 is made of nickel plated material such as Kovar. In this case, base 1 and can 1
0 and the outer periphery of the base 11
It is distinctive in that it is not plated with gold.

In the case of high-reliability semiconductors or integrated circuits, die bonding uses gold-based brazing materials (e.g. Au/Si,
(Au/Ge, Au/Sn, etc.), die bonding is performed on the gold plating 6 part of the header. In addition, since the surface conductor layer of a highly reliable semiconductor or integrated circuit is made of gold, a thin gold wire 9 is used as the wiring material to connect the gold plated portion 6 of the header and the lead 3.
Wire bonding between. On the other hand, in the case of hermetically sealing, the overlapping portion of the base plating layer 5 of the header and the can 10 is welded in the direction of arrow 12 using a laser welder. At this time, since the overlapping portion of the base 1 and the can 10 is not plated with gold, the laser beam is hardly reflected and is efficiently absorbed, making it possible to weld.

As explained above, the header 1 made of metal that is not partially plated with gold is manufactured using a laser welding machine.
In order to weld the Can 10 with the Can 10, it does not allow moisture to pass through unlike semiconductors or integrated circuit devices using polymeric resin materials, making it an ultra-high reliability integrated circuit airtight package. Since it can be used effectively, by adding a numerical control mechanism, an airtight package with a complicated shape and size is not limited.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a header according to an embodiment of the present invention;
Figure 2 is an enlarged cross-sectional view of the welded part of the header in Figure 1.
FIG. 3 is a partially exploded perspective view of an integrated circuit device using a header according to an embodiment of the present invention. In the diagram: 1...Base, 2...Glass, 3...Lead,
4... Base base material, 5... Base plating layer, 6... Gold plating layer, 7... Integrated circuit board, 8... Brazing material, 9
...Gold wire, 10...Kyan, 11...Outer periphery,
12...Arrow. It is.

Claims (1)

[Claims] 1 Consisting of a base on which a semiconductor or integrated circuit board is mounted and has a predetermined number of lead terminals, and a can member that covers this base, the parts of the base to be welded to the semiconductor or integrated circuit board are plated with gold, and the base is An airtight package for an integrated circuit, characterized in that a portion to be welded to the can member and an outer circumferential portion thereof are non-photoselectively plated, and the base and the can member are welded by laser welding.