JPS606544B2 - Manufacturing method for airtight terminals - Google Patents

Description

[Detailed Description of the Invention] m Field of Application of the Invention The present invention relates to a method for manufacturing an airtight terminal, and in particular, a glass terminal in which a lead wire is hermetically and insulatively sealed to an iron eyelet through glass, and a copper base. The present invention relates to a method of manufacturing an airtight terminal, such as a stem for a semiconductor device or a stem for a crystal resonator, which is brazed to the stem.

'2} In the prior art, a stem used as a container for a power transistor for electric power has a structure shown in FIG. 1, for example.

In the figure, reference numeral 1 denotes a glass terminal, which is manufactured by sealing a lead wire 4 in an iron eyelet 2 through a glass 3 in an airtight and insulating manner. Reference numeral 5 denotes a base made of copper, that is, a stem board, which is approximately diamond-shaped and has mounting holes 6 at both ends in the longitudinal direction for attaching to a chassis, etc., and a through hole 7 for fixing a glass terminal at a position eccentric from the center. Furthermore, the through hole 7 is provided with a concave groove 8.

Reference numeral 9 denotes an iron cap welding ring which is fixed in the groove 8 with iron alloy. The stem having the above structure has conventionally been manufactured as follows.

First, as shown in FIG. 3, an electrolytic nickel plating layer 10 having a thickness of about 3 to 71 mm is formed on the entire surface of the eyelet 2.
Assemble the eyelet 2 and the lead wire 4 to the glass tablet in a predetermined relationship position using a sealing jig, and
A glass terminal 1 is manufactured by heating the glass tablet to a temperature of 100°C to melt it. Next, this glass terminal 1 is inserted into the through hole 7 of the stem board 5 and caulked to temporarily fix the glass terminal 1, and a welding ring 9 is placed in the groove 8.
Silver solder is placed around the outer periphery of the eyelet 1 and the outer periphery of the welding ring 9, and heated to about 78,000 ℃ in a neutral atmosphere.
The eyelet 2 and the welding ring 9 are made by melting the c.
The stem board 5 was brazed. However, the above manufacturing method has the following problems.

A: Many leak failures occur during rapid heating tests.

B: A nickel plating layer 10 is formed on the surface of the eyelet 2, and the surface material is different from that of the copper stem board 5, so if finish plating is applied immediately, the plating adhesion on the nickel plating layer 10 will be insufficient. Therefore, it is necessary to activate the nickel plating layer 10 as a pretreatment for final plating.

C Nickel plating layer 1 Since silver solder has good flowability, the molten solder material flows to the top of the glass 3, causing cracks.

[3- Purpose of the Invention Therefore, the main purpose of the present invention is to provide a method for manufacturing a hermetic terminal that does not have the above-mentioned problems.

■ General description of this invention To summarize this invention, a glass terminal is manufactured by sealing a lead wire in an airtight and insulating manner through glass to an eyelet having a copper laminate layer on the entire surface, and this glass terminal is made of copper. After fitting into the through hole of the base of the glass terminal, the eyelet of the glass terminal
It is characterized by adding o and o.

■ Embodiments The above-mentioned objects and other objects and features of the present invention will become more apparent from the following detailed description with reference to the drawings.

FIG. 4 shows an enlarged sectional view of a main part corresponding to FIG. 3 when the present invention is applied to the stem for a semiconductor device shown in FIGS. 1 and 2. FIG.

First, a copper glazing layer 11 having a thickness of about 3 to 12 squares is formed on the entire surface of the iron eyelet 2. In addition, soda barium glass or soda lime glass is crushed to the extent that it passes through a 100-200 mesh node, kneaded with an organic binder such as Carbowax (trade name), and then reduced to a particle size of 50-145'' using a spray dryer or the like. It is granulated, press-molded into a cylindrical shape, and heated to approximately 500°C to burn off the organic/binder to produce a glass tablet.
Lead wires 4 are manufactured by cutting a long wire made of nickel alloy into appropriate lengths, and are subjected to oxidation treatment if necessary.
Next, the eyelet 2, the glass tablet, and the lead wire 4 are directly assembled in a predetermined relationship using a sealing tool made of graphite, and heated to about 1000° C. in a neutral or weakly reducing atmosphere. A glass terminal 1 is manufactured by melting the tablet and sealing a lead wire 4 to an eyelet 2 through a glass 3 in an airtight and insulating manner. The glass terminal 1 and the stem substrate 5 are temporarily fixed by iron-bonding them and mechanically caulking them.

Further, an iron welding ring 9 is disposed in the groove 8 of the stem board 5, and the groove 8 on the outer periphery of the eyelet 2 protruding from the upper surface of the stem board 5 and the outer periphery of the welding ring 9.
Silver inside. A wax material such as corrugated iron is placed in a neutral atmosphere, and the
According to the above-described manufacturing method in which the airtight 2 and the welding ring 9 are hermetically fixed to the stem substrate 5 by heating to 0° C., there are the following advantages compared to conventional manufacturing methods.

a The combination of the glass 3 and the copper plating layer 11 has better adhesion than the combination of the glass 3 and the nickel plating layer 10, and a strong airtight seal can be achieved.
The sealing interface between the eyelet 2 and the glass 3 is caused by the release of compressive stress in the eyelet 2 due to the enlargement of the through hole 7 due to the expansion of the stem substrate 5 due to rapid heating when a semiconductor element is soldered thereon. This eliminates leakage defects.

For example, if the outer/inner/light ratio of eyelet 2 is 1.3 and the stem is 3.
When rapidly heated to 30 oo, the copper glazing layer 1 according to the present invention
In the case of the glass terminal having the nickel plating layer 10, there were no leak defects in the 5 cases, whereas in the conventional glass terminal with the electrolytic nickel plating layer 10 formed, the leak defect occurred in 1 case out of 50. b Since the copper plating layer 11 is formed on the surface of the eyelet 2, the surface of the eyelet 2 and the surface of the stem board 5 are made of copper, and nickel cannot be activated like the conventional nickel plating layer 10 before finishing plating. Processing becomes unnecessary.

c Compared to the nickel plating layer 10, the steel plating layer 11 prevents molten brazing material such as silver solder from flowing too much, so the molten brazing material does not flow to the glass 3, which not only prevents the occurrence of glass cracks but also prevents the eyelet from flowing. A required amount of brazing material is secured at the corner portion between the stem substrate 2 and the stem substrate 5, and highly reliable brazing can be performed.

5 and 6 show a plan view and a sectional view of another stem for a semiconductor device to which the present invention can be applied.

In the figure, reference numeral 1 denotes a glass terminal, in which a copper laminate layer 11 is formed on the entire surface of an iron eyelet 2, as in FIG. There is. This is a circular heat dissipation plate as an example of a base made of copper, and a through hole 21 for the iron fitting of the glass terminal 1 is formed at a position eccentric from the center.

22 is an iron flange, the outer shape of which is the same as the stem board 5 in Fig. 1.
Similarly, it has a substantially rhombic shape, and has mounting holes 23 at both ends in the longitudinal direction for attaching to the chassis, etc., and a round hole 24 in the center for fitting the heat dissipation plate 20.

The entire surface of the iron flange 22 is plated with copper, and then the heat sink 20 is iron-fitted into the round hole 24, temporarily fixed by caulking, and the glass terminal 1 and the heat sink 20 are brazed together. At the same time, the heat sink 20 is brazed. 7 and 8 show a plan view and a sectional view of a stem for a crystal resonator as another airtight terminal to which the present invention can be applied.

In the figure, a Mitsukawa glass terminal has through holes 32 at both ends of the longitudinal direction of an eyelet 31 made of an oblong iron plate, and after forming a copper laminate layer on the entire surface, a glass 33 is inserted into the through hole 32. The lead wire 34 is hermetically and insulatively sealed via the . Reference numeral 35 designates a boat-shaped container as an example of a base made of copper, and has a through hole 36 having the same D shape as the through hole 32 and a slightly larger diameter. The protrusions on the periphery of 32 are mated together.

The eyelet 31 and the container 35 are hermetically brazed with a soldering material such as silver solder. The same effects as described in the above embodiment can also be obtained in the semiconductor device stems shown in FIGS. 5 and 6 and the crystal resonator stems shown in FIGS. 7 and 8.

It should be noted that the present invention can also be applied to airtight terminals other than the above-mentioned embodiments.

'6' Summary As described above, this invention produces a glass terminal by forming a copper coating layer on the entire surface of an iron eyelet, and sealing a lead wire in this eyelet in an airtight and insulating manner through glass. The process includes a step of iron-bonding this glass terminal to a through hole in a copper base, and a step of brazing the eyelet of the glass terminal to the base, so it is not necessary to form a nickel plating layer on the surface of the conventional eyelet. Compared to those using glass-sealed glass terminals, it is possible to obtain airtight terminals with no leakage defects due to rapid heating, eliminate the need for nickel activation treatment before final plating, and prevent excessive flow of molten brazing material. This not only prevents the occurrence of glass cracks, but also ensures the required amount of brazing material in the brazed portion, resulting in a highly reliable airtight terminal.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a stem for a semiconductor device, which is the background of the present invention and to which a manufacturing method according to an embodiment of the present invention is applied; FIG. 2 is a sectional view taken along the line 0-RO in FIG. FIG. 3 is an enlarged cross-sectional view of the main parts for explaining the manufacturing method of the stem for the semiconductor device shown in FIGS. 1 and 2, and FIG. FIG. 5 is a plan view of a stem for a semiconductor device for explaining another embodiment of the present invention; FIG. The figure is a sectional view taken along the mark line in FIG. 5, FIG. 7 is a plan view of a stem for a crystal oscillator for explaining still another embodiment of the present invention, and FIG. FIG. 3 is a sectional view taken along a straight line. 1, 30... Glass terminal, 2, 31... Eyelet, 3, 33... Glass, 4, 34... Lead wire, 5
, 20, 35...Base (stem board, heat sink, container), 7, 21, 36...Through hole, 11...
・...Copper finish layer, 22...Flange. Kei 7 Diagram Nai 2 Diagram Purple 3 Diagram *I, Diagram Shigezu Diagram 6 Younger brother 7 Diagram Memuro 8

Claims (1)

[Claims] 1. A step of manufacturing a glass terminal by forming a copper plating layer on the entire surface of an iron eyelet and sealing a lead wire inside the eyelet in an airtight and insulating manner through glass, and a step of manufacturing a glass terminal. A method for manufacturing an airtight terminal, comprising the steps of fitting the glass terminal into a through hole of a copper base, and brazing the eyelet of the glass terminal to the base. 2. The method for manufacturing an airtight terminal, particularly a stem for a semiconductor device, according to claim 1, wherein the base is a stem substrate having a substantially rhombic shape. 3. The method for manufacturing an airtight terminal, particularly a stem for a semiconductor device, according to claim 1, wherein the base is a circular heat sink, and further includes a substantially diamond-shaped iron flange on the outside thereof. 4. The glass terminal is manufactured by hermetically and insulatively sealing the lead wires into the through holes at both longitudinal ends of an oval eyelet through glass, and the base is a boat-shaped container, the patent states. A method for manufacturing an airtight terminal, particularly a stem for a crystal resonator, according to claim 1.