JPS6351539B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an airtight terminal having a ground lead wire and a method for manufacturing the same, and more specifically, the lead wire is hermetically welded with glass and the ground lead wire is bonded to a metal by resistance welding. For those welded to the ring, the glass is hermetically welded and has good airtight properties, and there is no glass flowing out from the element attachment part or cap fixing part (flange part) on the top surface of the metal outer ring, making it easy to attach the element or cap. The present invention relates to an airtight terminal having an earth lead wire that can ensure sealing, and a simple method for manufacturing an airtight terminal having an earth lead wire that can be resistance welded very easily and without impairing airtightness properties.

Airtight terminals for mounting semiconductor devices, etc. have lead wires that are insulated by glass and implanted in the metal outer ring that is the device mounting part, and electrical continuity is ensured by resistance welding. There is a type that has a ground lead wire. This hermetic terminal has Au plating etc. applied to the upper surface of the metal outer ring, the semiconductor element is tightly fixed by Au-Si eutectic alloy, etc., and the legs of the cap are hermetically sealed around the periphery. sealed in. In this case, airtightness is required between the glass to which the lead wires are welded and the lead wires, between the glass and the metal outer ring, etc., so as to be able to withstand the above-mentioned element attachment temperature. On the other hand, the element attaching portion and the cap fixing portion of the metal outer ring are required to have sufficiently clean and smooth surfaces from which glass does not flow out.

A conventional hermetic terminal is shown in FIG. In the figure 1
0 is a metal outer ring, 12 is a lead wire, and glass 14
It is implanted in the metal outer ring 10 by the following. Also 1
Reference numeral 6 denotes a ground lead wire, which is welded to the inner upper surface of the metal outer ring 10 by resistance welding using a nail portion at its upper end. To form this airtight terminal, first the ground lead wire 16 is welded to the metal outer ring 10 by resistance welding, and then the ground lead wire 16 is welded to the metal outer ring 10 by resistance welding.
A metal oxide film is formed on the entire metal outer ring 10 including the metal outer ring 6 to improve wettability with glass, and then the lead wire 12 is fixed with the glass 14, and the semiconductor element 18 and the cap 20 are further fixed. I try to do that. However, when a metal oxide film is formed on the entire surface of the metal outer ring 10 as described above, the wettability of the glass 14 to the metal oxide film is good, so it is effective in terms of airtight welding of the glass 14 to the inner surface of the metal outer ring 10. However, the glass 14 is connected to the lead wire 1
2 flows out onto the metal oxide film on the upper surface of the metal outer ring 10 through the insertion hole, etc., and adheres to the element attaching part and cap fixing part, which poses a problem in that it becomes an obstacle to attaching the element and sealing the cap. The above metal oxide film has a spinel type that has good wettability on glass due to the material of the metal outer ring (Fe-Ni alloy, Fe-Ni-Co alloy, etc.).
It is formed on oxides such as Fe ₃ O ₄ and Fe ₂ CoO _4. If this metal oxide film is thick, it has excellent airtightness, but the above-mentioned problem of glass flowing out occurs, and on the other hand, if it is thin, it There is a contradictory relationship in that the problem of leakage is eliminated, but the airtightness is inferior. The range of metal oxide film thickness that satisfies both is narrow, and it is practically impossible to adjust the thickness alone. In the past, metal oxide films were formed to have a large thickness with emphasis placed on the more important airtightness, and it was necessary to accept a drop in yield due to glass flowing out.

Furthermore, in the above conventional example, since the metal oxide film is formed after resistance welding the ground lead wire 16, the ground lead wire 16 is
There is also the disadvantage that the ground lead wire 16 may become bent and loose, and the ground lead wire 16 may become dull due to cooling after high-temperature oxidation, and may be easily deformed during handling in subsequent processes.

To solve the above-mentioned problems, first, a metal oxide film is formed on the entire metal outer ring 10, then the metal oxide film is removed by barrel polishing or the like except for the inner surface of the metal outer ring 10, and then A method is known in which a portion of the metal oxide film on the inner surface of the ground lead wire 10 is removed in spots with a drill or the like, and the upper surface of the nail portion of the ground lead wire 16 is brought into contact with the spot and resistance welded. In this conventional example, since the metal oxide film on the upper surface of the metal outer ring 10 is removed, the metal oxide film can be formed as thick as necessary and glass can be prevented from flowing out. However, the ground lead wire 1
6 to the inner upper surface of the metal outer ring 10, it is essential to peel off a portion of the metal oxide film on the inner surface of the metal outer ring 10. Peeling work is troublesome, and even when resistance welding, one electrode is brought into contact with the outer upper surface of the metal outer ring 10, and the other electrode is inserted into the narrow recess of the metal outer ring 10 to connect the ground lead wire. There is a problem in that the workability is extremely poor, such as having to press the top of the nail part 16.

The present invention has been made to solve the above-mentioned problems, and its purpose is to provide an airtight terminal having a ground lead wire that has excellent airtightness and can be manufactured at a high yield without glass flowing out at the element attachment part or the cap fixing part. The feature is that a metal oxide film is formed on the outer peripheral surface of the lead wire and the entire inner surface of the U-shaped cross section of the metal outer ring, which is thick enough to allow the glass to be hermetically welded. The upper end of the ground lead wire is formed in a nail portion protruding from the upper surface of the U-shaped section, and is welded to the outer upper surface of the U-shaped section at the lower surface of the nail by resistance welding.

Another object of the present invention is to provide a method for manufacturing an airtight terminal having a ground lead wire, which allows resistance welding of the ground lead wire easily and reliably. A metal oxide film with a thickness sufficient for glass to be hermetically welded is formed on the metal outer ring, and then the metal oxide film on the metal outer ring is removed except for the inner surface of the U-shaped cross section of the metal outer ring. A ground lead wire with a nail portion formed at the upper end is inserted through a through hole provided on the upper surface of the U-shaped portion, and the nail portion is connected by an electrode in contact with the upper surface of the nail portion and an electrode in contact with the outer upper surface of the U-shaped portion in cross section. The lower surface is resistance welded to the outer upper surface of the U-shaped section, and then the inside of the U-shaped section is filled with glass, and the lead wire, which has a metal oxide film formed on the outer peripheral surface in advance, is insulated to the metal outer ring. It's there to plant.

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

Fig. 2 shows an airtight terminal according to the present invention, and in the figure, 30 is a metal outer ring, which has a U-shaped cross section with a downwardly open center part, and a flange part for sealing the cap at the lower part of the periphery. There are 32 surrounding areas. On the entire inner surface of the U-shaped cross section of the metal outer ring 30,
A metal oxide film is formed with a sufficient thickness to improve the wettability of the glass to improve airtightness, which will be described later.

34 is a ground lead wire, which is inserted through the insertion hole 36 provided in the metal outer ring 30 and connected to the nail portion 38 at the upper end.
protrudes from the upper surface of the U-shaped section, and is hermetically welded to the outer upper surface of the U-shaped section at the lower surface of the nail portion 38 by resistance welding. A lead wire 40 is inserted through a relatively large-diameter insertion hole 42 provided in the metal outer ring 30 and is insulated and implanted through a glass 44.

Next, a method for manufacturing the above airtight terminal will be explained.

First, a metal oxide film is formed on the entire front and back surfaces of the metal outer ring 30. This process is a heating process at around 700°C and is carried out in an oxidizing atmosphere. The film thickness is set to be sufficient to ensure wettability with the glass 14. Next, this metal outer ring 30 is polished by barrel polishing or the like.
As shown in FIG. 3, the metal oxide film is removed except for the inner surface of the recess of the metal outer ring 30.

Then, as shown in FIG. 4, the ground lead wire 34 is inserted through the insertion hole 36, and one electrode 46 is brought into contact with the upper surface of the nail portion 38 of the ground lead wire 34, and the other cylindrical electrode 48 surrounding the nail portion 38 and in contact with the outer upper surface of the metal outer ring 30,
The ground lead wire 34 is resistance welded to the outer upper surface of the metal outer ring 30 at the lower surface of its nail portion 38 using both electrodes. Finally, as in the prior art, the lead wire 40, on which a metal oxide film has been previously formed at a predetermined position on its outer peripheral surface, is implanted in the metal outer ring 30 through the glass 44.

As described above, according to the airtight terminal according to the present invention,
The metal oxide film on the inner surface of the metal outer ring is formed to a sufficient thickness, so its airtightness is good, and the element mounting area and flange area on the top surface of the metal outer ring are clean surfaces with no glass flowing out. Therefore, it is possible to securely attach the element and ensure hermetic sealing with a cap. Further, according to the method for manufacturing an airtight terminal according to the present invention, the ground lead wire can be easily resistance welded without impairing the airtightness characteristics, and the glass for fixing the lead wire can be attached to the element attaching part or the flange part on the upper surface of the metal outer ring. It is effective in that it does not flow upward, allows for reliable mounting of elements and sealing of caps, and allows for high-yield manufacturing.

Although the present invention has been variously explained above with reference to preferred embodiments, the present invention is not limited to these embodiments, and it goes without saying that many modifications can be made without departing from the spirit of the invention. It is.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a conventional airtight terminal, FIG. 2 is a sectional view of an airtight terminal according to the present invention, FIG. 3 is an explanatory view showing a portion of the metal outer ring where a metal oxide film remains, and FIG. 4 FIG. 2 is an explanatory diagram showing a method of resistance welding a ground lead wire. 10...Metal outer ring, 12...Lead wire, 14...
...Glass, 16...Earth lead wire, 18...Semiconductor element, 20...Cap, 30...Metal outer ring, 32...Flange portion, 34...Earth lead wire, 36...Insertion hole, 38... Nail club, 40...
... Lead wire, 42 ... Insertion hole, 44 ... Glass,
46... Electrode, 48... Cylindrical electrode.

Claims (1)

[Scope of Claims] 1. A metal outer ring having a U-shaped cross section with a downwardly open central portion and a flange portion for sealing the cap at the lower peripheral edge, and the above-mentioned U-shaped portion in cross section. In an airtight terminal in which a lead wire is insulated and implanted by glass filled with glass, and a ground lead wire is inserted through the glass and resistance welded to the metal outer ring, the outer circumferential surface of the lead wire and A metal oxide film is formed on the entire inner surface of the U-shaped cross section of the metal outer ring with a thickness sufficient for the glass to be hermetically welded, and the upper end of the ground lead wire is connected to the upper surface of the U-shaped cross section. It is formed on the nail part that protrudes from the
What is claimed is: 1. An airtight terminal having a ground lead wire, characterized in that the nail is welded to the outer upper surface of a U-shaped cross section on the lower surface of the nail by resistance welding. 2. A metal outer ring, which has a U-shaped cross section with a downwardly open center and a flange for sealing the cap at the lower periphery, is filled with glass to be filled in the U-shaped cross section. Therefore, in a method for manufacturing an airtight terminal in which a lead wire is insulated and implanted, and a ground lead wire is resistance welded to the metal outer ring by passing through the glass, first, the glass is applied to the entire surface of the metal outer ring. A metal oxide film with a thickness sufficient for airtight welding is formed, and then the metal oxide film on the metal outer ring is removed except for the inner surface of the U-shaped cross section of the metal outer ring, and the metal oxide film is removed from the metal outer ring except for the inner surface of the U-shaped cross section. A ground lead wire with a nail portion formed on the upper end is inserted through the through hole provided on the upper surface, and the lower surface of the nail is connected to the cross section by the electrode in contact with the upper surface of the nail portion and the electrode in contact with the outer upper surface of the U-shaped cross section. Resistance welding is performed on the outer upper surface of the U-shaped portion, and then glass is filled inside the U-shaped portion in cross section, and a lead wire with a metal oxide film formed on the outer peripheral surface is insulated and implanted in the metal outer ring. A method for manufacturing an airtight terminal having a ground lead wire, characterized by: