JPS60113449A - Manufacture of lead pin with difficultly processed solder - Google Patents

Abstract

PURPOSE:To prevent the generation of soldering failure at the time of mounting lead pins by a method wherein a difficultly processed solder of Au-Sn alloy, etc. is previously brazed to the lead pins or a lead frame. CONSTITUTION:The lead pins 3 are inserted into many holes 2 of a carbon jig 1, and Au-Sn 20% alloy balls 4 are placed thereon one by one and then set-up; thereafter, welded by heating at 350 deg.C in a furnace with hydrogen atmosphere. The lead pins 3' with Au-Sn 20% alloy solder 4' obtained in such a manner are inserted into 1,000 holes 7 of the carbon jig 6 set-up on an Ni plate 5 respectively, with the solder 5' lower side, and this solder 4' is set up in contact with the Ni plate 5, thus brazing the lead pins 400 deg.C in a furnace with nitrogen atmosphere. Thus, the generation of the soldering defects in lead pin mounting can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for manufacturing REIT pins in which a difficult-to-process material such as Au-3n alloy or Au-Al alloy is attached as a brazing material in advance to terminals used in containers for integrated circuits and electronic devices. Regarding the manufacturing method.

Au-3n alloy has poor workability at room temperature, so in the past, ingots were made by final processing, then hot-processed into strips or plates, and then cut or pressed to produce brazing materials as preform materials. It was served to

(1) But article +1. When rolling plate materials, due to poor workability, edge cracks are likely to occur, and if edge cracks occur, that part has to be cut out, resulting in a very poor material yield.
Moreover, there were problems such as processing time.

In addition, the lead pin is made by processing Fe-Ni alloy or Fe-Ni-Co alloy material into a pin shape, and one end of this is placed on a metalized ceramic substrate.
In this method, when inserting the Au-3N alloy solder into the hole of the carbon jig set on the ceramic substrate, two pieces are placed on top of the Au-3N alloy solder. Brazing between the lead pin and the metallized coating on the ceramic substrate is prone to failure due to mistakes such as tying or forgetting to insert the lead pin, rust etc. Nowadays, defective brazing has a 100 times greater impact on the manufacturing yield of containers. If brazing has a failure rate of 0.1%, the failure rate of containers would be as high as 10%2) Therefore, brazing is a method that is two or three orders of magnitude more reliable. The appearance of was requested.

The present invention has been developed in view of the above circumstances, and is a method of brazing that is difficult to process, which can dramatically improve the reliability of brazing lead pins, and also improve the manufacturing yield of brazing filler metal, which is difficult to process. It is an object of the present invention to provide a method for manufacturing a lead pin with a braze.

An embodiment of the method for manufacturing a difficult-to-process brazing material ivory pin according to the present invention will be described in detail below.

Using Au with a purity of 99.995%, the outer diameter is 4. A pipe with Qmm, inner diameter 2.63m+a, and length 1m was created, and a Sn wire with a diameter of 2.51111 and a length of 1.1m was inserted into this pipe, and it was drawn down to a diameter of 0.5mm using a drawing process, and A u /
A cladding wire of S n was made. This clad wire was cut into lengths of 0.51 mm using a small press, and the pieces were arranged on a carbon tray and heated and melted at 850° C. in a non-oxidizing atmosphere to form spheres. As a result of analyzing this ball, Au and S
The component ratio of n was 80%-20%, and it was confirmed that the alloy was uniform.

(3) Next, as shown in FIG. 1, insert the lead pins 3 into the numerous holes 2 of the carphone jig 1, and attach the Au-S to the upper end of each lead pin 3.
n After placing and setting the 20% alloy one by one,
Heat welding was carried out at 350°C in a hydrogen atmosphere furnace. As a result of inspecting each of the lead pins 3 to which the 20% A, u-S n alloy was heat-welded under a microscope under magnification of 20 times, it was found that all of the A u -S
It was confirmed that the n20% alloy was remelted and fused to the lead pin 3 as shown in FIG.

However, A LJ-S n 20 manufactured as above
Lead pin 3' with % brazing filler metal 4'! 10001 of the carbon jig 6 set on the Nl plate 5-A as shown in Figure A3.
A u - S n 20% brazing filler metal 4' in each dark hole 7
The solder metal 4' was brought into contact with the Nl plate 5, and the lead pins 3' were brazed at 400°C in a nitrogen atmosphere furnace for seven minutes. As a result, all the lead pins 3' were As shown in Fig. 4, a uniform meniscus is formed and the lead pins 3 are soldered to the Ni plate 5, and even in three 90 degree bending tests, none of the lead pins 3 detached from the Ni plate (4) or cracked. There was absolutely nothing to do.

In the above embodiment, a case was explained in which a lead pin with a brazing material made of Au-Sn alloy was manufactured, but the invention is not limited to this, and it is also possible to manufacture a lead pin with a brazing material made of Au-Sn alloy and other alloys that are difficult to process. This applies to

As can be seen from the above explanation, the method for manufacturing lead pins with a difficult-to-work brazing material of the present invention involves brazing the lead pin (or lead frame) with a difficult-to-work brazing material such as an Au-Sn alloy in advance, so it is easy to attach the lead pin. During brazing, the occurrence of defects can be dramatically reduced.

In addition, when brazing the ceramic and lead pin in advance, the temperature is much lower than the melting point, and it is possible to check the melting of the filler metal and screen out defective ones, so that melting during the soldering due to segregation of impurities and components can be avoided. There is no need to worry about residue or poor flow.

Even the brazing filler metal, which is difficult to work with, has good workability when it comes to its single elements. Therefore, after making solid pieces of single elements of a certain size and volume in advance, they are heated and melted to form a spherical shape (5). Not only is the material processing easy (but the volume of the filler metal attached to the Riet pin is constant"ζ,
It has excellent effects such as being able to obtain a lead pin with a difficult-to-process brazing material that has high brazing reliability.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a state in which a brazing filler metal is brazed to a lead pin in the manufacturing method of the difficult-to-process brazing material (=J lead pin) of the present invention, and Fig. 2 is a diagram showing the difficult-to-process brazing material obtained by the manufacturing method of the present invention. A diagram showing a lead pin with workable brazing material, Figure 3 is a diagram showing a state in which the hard-to-workable brazing material of Figure 2 is welded to an Nl plate, and Figure 4 is a diagram showing a state in which the lead pin with a brazing material that is difficult to work is welded to an Nl plate. It is a diagram showing a state where it is brazed on a Ni plate and a bending test method for testing its bonding strength.
---1-Lead pin, 3 ゛---Lead pin with brazing material, 4. ------- At+-3n 20% alloy alloy 5------ Ni plate, 6---Carbon jig, 7
----- One hole. Applicant Tanaka Kikinzoku Kogyo Co., Ltd. (6) Figure 4

Claims (1)

[Claims] A clad material is made using a single element of VFT workable material or an alloy with relatively good workability, and then processed to the required size or volume, heated and melted to form an alloy, and then A method for producing a lead pin with a hard-to-process brazing material, which is characterized by melting and attaching the lead pin to the lead pin at high temperature.