JPH0320870B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an airtight terminal and a method for manufacturing the same.
More specifically, by interposing a metal sleeve in the insertion hole to which the ground lead wire is brazed,
The brazing material can be saved, and the insertion hole itself can be formed with a large diameter, so the press punch can be pressed easily without buckling.Furthermore, by using pure silver as the brazing material, it is possible to braze the ground lead wire. The present invention relates to an airtight terminal and an efficient manufacturing method thereof, which can perform the process and the glass welding process of other lead wires at the same time, thereby reducing the number of man-hours and costs.

An airtight terminal for mounting a semiconductor device, etc. has a lead that is insulated by glass and is implanted in the metal outer ring that is the device mounting part, with the tip protruding from the top of the device at almost the same height. There is a type that has a wire and a ground lead wire that is implanted while maintaining electrical continuity with the metal outer ring using a brazing material.

The tips of each of these lead wires are plated with gold and wire bonded to the element.

The insertion holes through which each lead wire is inserted are designed to save expensive silver solder for the ground lead wire.
Also, in consideration of the flowability of the solder during brazing, a small diameter is required.

However, for example, 0.5 mm in a 1.5 mm thick metal outer ring
It is extremely difficult to drill a press punch hole of approximately mmφ because the press punch may buckle or break. Generally, such press punched holes can have a diameter up to about 0.7 times the thickness of the member.

To deal with this problem, as shown in Fig. 1, a bottomed recess 2 with a relatively large diameter and a depth of approximately half the thickness of the metal outer ring 1 is provided, and this is filled with silver solder. There is one in which an insertion hole 3 of a required small diameter is pressed into the thinned bottom part.

However, this method has the following drawbacks. That is, as mentioned above, the ground lead wire 4 is brazed with its tip protruding according to the thickness of the element, but depending on the thickness of the element, the tip of the ground lead wire 4 may extend beyond the surface of the metal outer ring 1. Only 0.3mm
Since the protrusion is only ~0.5 mm, if the amount of silver solder filled in the large volume bottomed recess 2 as mentioned above is even slightly large, the silver solder may have extremely good wettability with the metal. This will creep up onto the tip of the ground lead wire 4, and this will have a negative effect on the gold plating that is later applied to the tip, causing blisters to form on the gold plating due to impurities in the silver solder, deteriorating the bonding characteristics. There is a drawback.

Conversely, if there is not enough silver solder, the surface of the silver solder will cave in and the length from the silver solder surface to the tip of the ground lead wire 4 will be longer than the required length, so when using an ultrasonic bonder, the tip will There are drawbacks such as resonance, which can cause wires to break.

The next problem is that conventionally, silver solder is used as a brazing material, so the brazing of the ground lead wire with silver solder and the glass welding of other lead wires have to be done in separate steps.

In other words, since glass has poor wettability with metal, it is necessary to form a metal oxide film on the metal surface to improve wettability and improve adhesion and airtightness.On the other hand, silver solder has poor wettability with metal. This is because they have contradictory properties such as poor wettability to the film. Another reason is that glass melts at about 700℃ and silver solder melts at about 800℃, but it takes about 1000℃ to make the glass adhere to the metal oxide film on the metal surface.
℃, and silver solder becomes extremely flowable when heated to this temperature, so it flows over the surface of the metal outer ring and forms the boundary between the inner wall of the insertion hole for other lead wires and the glass. This is because it has the disadvantage of deteriorating airtightness by penetrating into the air.

For this reason, glass welding and silver brazing had to be performed in separate processes, leading to an increase in costs.

The present invention has been made in view of the above-mentioned problems, and its purpose is to save the amount of brazing filler metal, and because the insertion hole itself can be formed with a large diameter, press processing can be carried out easily without buckling the press punch. , an airtight terminal having a ground lead wire implanted in each insertion hole provided in a metal outer ring with a brazing material, and a lead wire insulated and implanted with glass; The insertion hole through which the wire is inserted is formed to have a sufficiently larger diameter than the earth lead wire so that it can be easily punched in the metal outer ring with a press punch, and the earth lead wire is loosely fitted into the insertion hole of the earth lead wire. An airtight terminal made by brazing pure silver through a metal sleeve, and an efficient method for manufacturing the same. In an airtight terminal having a lead wire and a lead wire insulated by glass and implanted, the ground lead wire insertion hole is punched with a press punch to a diameter sufficiently larger than that of the ground lead wire, and The ground lead wire is inserted into the ground lead wire insertion hole via a metal sleeve that is loosely fitted and held in the ground lead wire insertion hole, and the lead wire is inserted into the lead wire insertion hole, To provide a method for producing an airtight terminal, characterized in that pure silver is used as a brazing material for the ground lead wire, glass is used for the lead wire, and pure silver brazing and glass welding are performed in the same process.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 shows a sectional view of the airtight terminal 10 according to the present invention, in which 11 is a metal outer ring, 12 is a lead wire, and 13 is a ground lead wire.

The lead wire 12 is welded into an insertion hole 14 formed in the metal outer ring 11 with a glass 15 with the tip thereof protruding upward. In addition, the ground lead wire 13 is
A metal sleeve 17 is loosely fitted into an insertion hole 16 formed in a large diameter in the metal outer ring 11, and is brazed into the insertion hole 16 with the tip thereof protruding upward using pure silver 18 as a brazing material. There is. Note that 19 is a nickel plating layer applied on the metal sleeve 17. This nickel plating is not limited to this, and any type of plating may be used as long as it has good adhesion to pure silver and airtightness.

Next, this manufacturing method will be explained with reference to FIG.

First, a lead wire insertion hole 14 and a ground lead wire insertion hole 16 are bored in the metal outer ring 11 by press working so as to have the required diameters described above.
Since this insertion hole 16 can be formed to have a large diameter, processing can be performed using a thick press punch without buckling or breaking the press punch.

As shown in the figure, this metal outer ring 11 is placed on a carbon jig 20 so that its insertion hole 16 corresponds to the recess 21 provided on the carbon jig 20. At this time, the other insertion holes 14 are also connected to the carbon jig 20.
This corresponds to a recess (not shown) provided above. Next, the metal sleeve 17, which has been plated with a metal having good wettability against pure silver such as nickel plating 19, is inserted into the insertion hole 16 so as to straddle the recess 21 and rest on the periphery thereof.
The height of the metal sleeve 17 is set to be slightly smaller than the thickness of the metal outer ring 11, and a ring-shaped pure silver 18 serving as a brazing material is placed on its upper surface. In this manner, the pure silver 18 is placed, the earth lead wire 13 is inserted into the metal sleeve 17, and the earth lead wire 13 and the metal outer ring 11 are fixedly positioned using the carbon jig 22. Although not shown, the lead wire insertion hole 14
The lead wire 12 is inserted into the housing, and the glass 15 is housed therein.

The assembly prepared as described above is placed in an electric furnace, and the metal outer ring 11, metal sleeve 17, and ground lead wire 13 are brazed with pure silver 18, and the glass 1
Welding of the metal outer ring 11 and the lead wire 12 according to No. 5 is performed at the same time.

When the temperature rises in the electric furnace, the glass first melts at around 700°C, which combines with the metal oxide film formed on the peripheral wall of the lead wire 12 and the inner wall of the lead wire insertion hole 14, making each of them airtightly adhered. It's getting old. Furthermore, by raising the temperature to around 960°C, the glass becomes more familiar with the metal and its adhesion improves. On the other hand, the pure silver 18 serving as the brazing material also melts at this temperature, but at this time, the metal oxide film on the ground lead wire 13, the nickel coating 19 of the metal sleeve 17, and the inner wall of the ground lead wire insertion hole 16 is removed from the carbon jigs 20, 22. The molten silver is decomposed by the reducing atmosphere created by the sterling process, gasified and released, so the molten pure silver has good wettability to the surrounding pure metal surface and is in an airtight state. It's summery. In this way, since the impurities gasify and escape, no cavities are formed in the pure silver, and a good airtight seal can be achieved.

The reducing effect of the carbon jigs 20 and 22 is exerted after the metal oxide film necessary for hermetically sealing the lead wire 12 combines with the molten glass and becomes a bond that is sufficiently compatible and difficult to be reduced. It is something.

However, when it is cooled and taken out, the lead wire 12,
It is possible to obtain an airtight terminal in which each of the ground lead wires 13 is well hermetically sealed.

Note that the plating applied to the metal sleeve 17 is not limited to nickel plating, but any material may be used as long as it has good wettability with pure silver and can be airtightly sealed.Furthermore, similar plating may be applied to the ground lead wire 13. It is something that

As described above, according to the present invention, since the metal sleeve is interposed in the insertion hole to which the ground lead wire is brazed, expensive brazing material can be saved, and the insertion hole itself can be formed with a large diameter, so that press Pressing can be performed easily without buckling the punch, and by using pure silver as the brazing material, the brazing conditions and glass welding conditions match, and both can be performed at the same time, reducing man-hours and costs. This has the remarkable effect that it is possible to reduce the amount of air-tightness, and to efficiently manufacture high-quality airtight terminals with excellent airtightness.

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 cross-sectional view showing an example of an airtight terminal according to the present invention, and FIG. 3 is a cross-sectional explanatory view showing a state in which each member is assembled into a carbon jig. 1, 11...metal outer ring, 2...bottomed recess, 4,
13...Earth lead wire, 10...Airtight terminal, 1
2... Lead wire, 14, 16... Insertion hole, 15...
... Glass, 17 ... Metal sleeve, 18 ... Pure silver, 19 ... Nickel metal layer, 20, 22 ...
Carbon jig, 21... recess.

Claims (1)

[Scope of Claims] 1. An airtight device having an earth lead wire implanted in each insertion hole provided in the metal outer ring with a brazing material and a lead wire insulated with glass. In the terminal, the insertion hole through which the ground lead wire is inserted is formed to have a sufficiently larger diameter than the ground lead wire so that it can be easily punched in the metal outer ring with a press punch, and the ground lead wire is An airtight terminal made by brazing sterling silver through a metal sleeve that is loosely fitted into the insertion hole. 2. In an airtight terminal having a ground lead wire implanted in each insertion hole provided in the metal outer ring with a brazing material and a lead wire insulated with glass, the ground lead A wire insertion hole is bored with a diameter sufficiently larger than that of the ground lead wire using a press punch, and the ground lead is inserted into the ground lead wire insertion hole through a metal sleeve that is loosely fitted and held in the ground lead wire insertion hole. Insert the wire into position,
A lead wire is inserted into the lead wire insertion hole, pure silver is used as a brazing material for the ground lead wire, glass is used for the lead wire, and pure silver brazing and glass welding are performed in the same process. A method for manufacturing an airtight terminal characterized by: