JPS58100967A - Manufacture of metallic parts - Google Patents

Abstract

PURPOSE:To form a beautiful, flawless plated surface in making finish plating after silver soldering a copper member to other member by Ni plating the copper member prior to silver soldering. CONSTITUTION:Holes 2 for fitting to a chassis, through holes 3 for sealing lead wires and through holes 4 for fitting a heat sink are pierced in a base plate 1 made by blanking a steel plate. Lead wires 6 made of Fe-Ni alloy and glass tablets 5 are attached to specified positions. Then, these are heated to 950- 1,050 deg.C in neutral or weakly reducing atmosphere and lead wires 6 are sealed in the holes 3 through glass 5. The whole surface of the heat sink 7 made of copper is Ni plated, and fitted to the hole 4, and fixed temporarily. Silver solder is placed around the heat sink 7, and heated to 800-900 deg.C to fix the heat sink to the base plate. Since the surface of the heat sink is Ni plated, poor adhesion of plating due to oil or stain does not occur. Finish plating with Au etc. is made on this surface.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a metal component, in which at least the copper side of a stem, base, camp, etc. used as a part of an airtight container of a semiconductor device IF is silver-brazed to a tsukage member. .

Many airtight containers for semiconductor devices use copper because of its electrical conductivity, thermal conductivity, and the like. For example, there is a stem having the structure shown in FIGS. 1 and 2. In the figure, the stem base υ) made by 1trii is roughly shaped like a star, has mounting holes 2, 2 at both ends in the longitudinal direction for attaching to the chassis, etc., and a through hole 3 for sealing the lead wire near the center. , 3, and has a through hole 4 in the center of the heat sink for connecting the heat sink. The through holes 3, 3 each have a crow 5.
, 5, the leads 6, 6 are sealed airtightly and insulated, while a copper heat sink 7 is hermetically sealed in the through hole 4 with silver solder. ? A stem having this type of structure has conventionally been manufactured in the following manner. Figure 3 shows a block diagram of the culm. First, a stem substrate l is manufactured by punching out an iron plate, and lead gauze 6 is manufactured by cutting a long iron/Ninkel alloy wire to an appropriate length.

In addition, fine glass powder such as soda barium glass or soda lime glass is kneaded with an organic binder, press-molded into a cylindrical shape, and then heated to about 500°C in an oxidizing atmosphere to burn out the organic binder. )5
Manufacture a and 5a. Then, the above stem substrate 1. Glass tab reso) 5a, 5a 2- and the lead wires 6, 6 are assembled in the predetermined relative positions using a layer-resistant jig made of graphite, and heated at a temperature of about 950 to 1050°C in a neutral or weakly reducing atmosphere. to form the glass tablet 5a.

5a is melted to seal the lead wires 6, 6 in the through holes 3, 3 of the stem substrate 1 through the glasses 5, 5 in an airtight and insulated manner. After that, a beat sink 7 made by cutting out a copper plate was fitted into the through hole 4 of the stem base &l, and after being temporarily fixed by caulking, it was placed on a graphite sealing jig, Silver solder is placed around the heat sink 7, and heated at a temperature of about 800 to 900°C in a neutral or weakly reducing atmosphere to melt the silver solder, and the heat sink 7 is hermetically sealed to the stem substrate l. Same arrival. Next, finish plating is applied to the entire structure using electric or electroless nickel plating.

By the way, if the heat sink 7 is punched out from a copper plate and then silver-plated onto the stem board 1, the dirt, oil, etc. on the surface of the heat sink 7 will be baked in, and the plating will not adhere well to the outside. &+1° defective. Therefore, l+r! before finishing plating or after welding process. Etching is done with k, etc. or polishing is done with a barrel, but if the silver solder is etched later, the silver solder will be dissolved and a silver nitrate layer will be formed on the surface of the heat sink 7, and the semi-IJj attachment of semiconductor pellets will deteriorate the properties. However, when barrel polishing occurs, the soft heat sink 70 is damaged due to collision with the hard stem substrate l.
There were problems in that not only the surface was easily damaged, but also the efficiency was poor because the number of treatments could not be increased. on the other hand.

If barrel polishing is performed using the heat sinks 7 after punching, the above-mentioned problems will be eliminated, but the occurrence of scratches due to collisions between the heat sinks 7 cannot be avoided.

Note that there are also stems for semiconductor devices and bases for semiconductor devices with structures other than those described above, in which the li+1I11 phase is silver-brazed and then finish-bladed, and such stems and bases also have the same problems as above. was there.

Therefore, the main object of the present invention is to provide a manufacturing method that can satisfactorily apply finish plating to at least the combination toy 4 (in a method of manufacturing metal parts in which the Lu portion H is silver-brazed and then finish plating is applied). It is to provide.

To summarize, the present invention is characterized in that the surface of a single copper member is electrically or electrolessly plated with nickel and then soldered with silver.

Hereinafter, actual designs and examples of this invention will be explained with reference to the drawings.

FIG. 4 is a culm bronch diagram of an example in which the present invention is applied to the production of the stem shown in FIGS. 1 and 2-1. 1. First, as in the past, the stem base &l+ lead wires 6, 6 and glass tablets 5a, 5a are manufactured, and these are assembled at predetermined relative positions using a sealing jig made of graphite 1, and neutral or Approximately 95% in a weakly reducing atmosphere
Heating at a temperature of 0 to 1050'c culm, lead %6.
6 is made airtight and insulated. On the other hand, what about the heat sink 7 as an example of a copper member made by punching out a copper plate? The entire surface of the product is coated with electric or non-electrical plating. : Nickel plating with a PI of about 0.5 to 5 is applied, and the heat sink 7 is fitted into the through hole 4 of the stem board l and temporarily fixed by caulking.
Silver solder is placed around the heat sink 7 and heated at a temperature of about 800 to 900° C. in a neutral or weakly reducing atmosphere, so that the heat sink 7 is hermetically fixed to the stem substrate 1. Thereafter, without barrel polishing (hi:+), the entire plate was electrically or electrolessly nickel plated or gold plated to a thickness of approximately 2 to 6 μm.

According to the above manufacturing method, nickel plating is applied to the heat sink 7 before silver soldering, so even if there is dirt, oil, etc. on the surface of the heat sink 7, the nickel plating will be applied neatly. In this way, the surface is coated with nickel plating and silver brazing is applied to the heat sink 7, so dirt and oil will not be baked onto the surface of the heat sink 7.
Therefore, with silver brazing, gaps such as poor plating density do not occur during the subsequent finish plating.

In addition to the above-mentioned practical example, the present invention also includes, for example: 6- A lead wire is hermetically and insulated through a glass in an iron eyelet in a lead wire sealing Hf through hole of a copper stem base ay to provide durability. In addition to soldering the layered airtight terminals with silver solder, the stem includes a steel gap welding ring attached to the annular groove on the top of the stem board, and a copper heat sink in the through hole of the iron flange. At the same time, the airtight 711, which has a thin layer of heat resistance, has a lead wire passed through the glass in the eyelet into the airtight terminal fitting hole of this heat sink. Manufactures 1 parts for semiconductor devices, such as stems for attaching metal parts with silver solder, and bases for semiconductor devices, which are made by silver soldering a copper heat sink to a through hole in the surface of a side-walled iron cylindrical body. It can also be applied when

As described in 2 below, the present invention is based on the first method of manufacturing gold-plated parts in which at least a copper member is soldered with silver on other parts and then finish plating is applied. Alternatively, since electroless nickel plating is applied and then silver brazing, the surface of the copper member is protected by nickel plating during silver soldering, and therefore, when punching is performed on the surface of the 1lqlIl autopsy. Dirt such as dirt and oil may stick to the
Can be fixed and finished - 〇 Plating can be done neatly and the surface of the copper member will not be scratched.

[Brief explanation of the drawing]

1 and 2 are a plan view of a stem for a semiconductor device shown as an example of a gold FJi component, and a top view of the stem taken along the line ■-n in FIG. ”・
FIG. 4 is a process block diagram for explaining the manufacturing method of the stem according to an example of the present invention. 1. Intermediate member (stem board), 5.. Glass, 5a. Crow tablet, 6.. Lead No. 1 country, 7..
・Heat sink. Fig. 1 23 574 2 Fig. 3 Fig. 4
X u7~L-4 anti-1↑ size Chopsticks

Claims (1)

[Claims] In the manufacturing method of parts, at least the copper part side is plated with silver braze, and the part side is silver soldered, and then final plating is applied. A method for manufacturing metal parts characterized by the following characteristics: