JPH04214659A - Manufacture of electric pin and electronic-pin intermediate body - Google Patents

Abstract

PURPOSE:To manufacture uniform pins simply, in a short time and simultaneously by a method wherein a metal layer which can be etched easily is formed on the outer circumference of a well conductive wire material, a resin which can easily be dissolved is coated and an electric-pin intermediate body is obtained. CONSTITUTION:A well conductive material, e.g. a copper wire 30, which is used as a blank for an electric pin and which has a desired diameter is passed through a well-known plating liquid; and an electric current is made to flow across it and a tin electrode. As a result, a tin-plated layer 31 whose thickness is sufficient is formed on the outer circumference of the copper wire 30. Then, the outer circumference of the tin-plated copper wire is coated with a ceramic resin 32; and an electric-pin intermediate body 33 is obtained. After that, the electric-pin intermediate body 33 is cut to a desired length which is suitable for a treatment; an epoxy hardening process by which many electric-pin intermediate bodies 33 lined up in a trimming process are fixed by using an epoxy resin 34 is executed; and an ingot 35 is obtained. The ingot 35 is cut in faces perpendicular to the axis of the electric-pin intermediate bodies 33 in a slicing process.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to electrical pins, particularly micro input/output (I/O) pins in general.
) This invention relates to a method of manufacturing a small electric pin called a pin, and an electric pin intermediate used therein.

[Conventional technology]

As electronic devices such as VLSI (Very Large Scale Integrated Circuits) and flat display panels that require large-scale, high-density, and high-speed operation are developed, the connection between these devices and the substrate (substrate or circuit board) is increasing. There is a need for simultaneous parallel interconnection devices, so-called electrical pins, I/O pins or micro input/output pins (hereinafter collectively referred to as electrical pins).

As the uses of such electric pins expand, various methods and devices for mass-producing them uniformly and inexpensively, as well as various related techniques, have been proposed. Examples of technologies related to these electric pins include JP-A-59-118269 and JP-A-6
No. 3-104460, Japanese Utility Model Application Publication No. 63-101167, Japanese Patent Application Publication No. 1-170035, Japanese Patent Application Publication No. 1-175761, and Japanese Patent Application Publication No. 1-235170. A similar technique is also disclosed in Japanese Patent Application Laid-Open No. 1-49266 filed by the applicant of the present application.

[Problem to be solved by the invention]

However, all of the conventional electrical pin manufacturing methods described in these publications not only have complicated manufacturing processes, but also require a considerable amount of time and are difficult to achieve uniform electrical and mechanical properties of the manufactured electrical pins. The disadvantage is that it is difficult to

In particular, if the copper rods used as the material for the electrical pins are solidified with epoxy resin, subsequent workability is improved, but it takes a long time to take out each electrical pin. Furthermore, it was difficult and time consuming to deposit a brazing filler metal containing a certain amount and correct ratio of gold and tin on the head of the electric pin.

Therefore, an object of the present invention is to provide a method for manufacturing an electric pin that has a simple manufacturing process and can simultaneously manufacture a large number of electric pins having uniform electrical and mechanical properties in a relatively short time, and an intermediate body for the electric pin used therein. shall be.

[Means to solve problems]

According to the present invention, an easily etched metal layer such as tin is formed on the outer periphery of a highly conductive wire material such as copper, and a layer of easily etched metal such as tin is further formed.
An electrical pin intermediate is obtained by coating an easily soluble resin such as lac).

Furthermore, this electric pin intermediate body is cut into predetermined lengths, arranged in parallel and spaced apart, and the whole is fixed with a resin such as epoxy. Thereafter, a number of electrical pins are manufactured simultaneously by slicing to a desired thickness to form a head using conventional techniques and dissolving the shellac layer with ethyl alcohol or the like.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of an electrical pin intermediate according to the present invention and a method of manufacturing an electrical pin using the same will be described in detail with reference to the accompanying drawings.

FIG. 1 is a process diagram for manufacturing an electrical pin according to a preferred embodiment of the present invention. 2(A) to 2(P) show explanatory diagrams of the main steps in FIG. 1.

First, the first step is a step 10 of preparing a wire of a highly conductive material, such as copper or copper alloy wire, having a desired diameter of, for example, 0.1 mm, which will be the material of the electric pin, and is supplied from, for example, a reel (not shown).

Next is step 11 of plating an easily etched metal, such as tin. A continuously supplied copper wire 30 is passed through a known plating solution and a current is passed between it and a tin electrode. As a result, a sufficiently thick tin plating layer 31 is formed around the outer periphery of the copper wire 30, as shown in FIG. 2(A). As is well known, the thickness of the tin plating layer 31 is determined by the amount of current and time.

In the next step 12, shellac resin 32 is coated around the tin-plated copper wire.

This electrical pin intermediate body 33, which is a tin-plated copper wire coated with shellac, is shown in FIG. 2(B). The shellac resin coating may be performed by repeating dipping and drying during the shellac resin pass.

Thereafter, the electrical pin intermediate body 33 shown in FIG. 2(B) is cut into a desired length suitable for processing, and an alignment step 13 is performed in which the electrical pin intermediate body 33 shown in FIG. An epoxy solidification process 14 is performed in which the large number of electrical pin intermediate bodies 33 aligned in the line alignment process 13 are fixed with a suitable resin 34 such as epoxy resin. As a result, a solidified electrical pin intermediate or ingot 35 shown in FIG. 2(C) is obtained.

This ingot 35 is cut into a predetermined length determined by the purpose of the electric pin in the slicing step 15, for example, from 0.6 mm to 1.0 m.
m, the electrical pin intermediate body 33 is cut (sliced) in a plane perpendicular to the axis thereof. Through this slicing step 15, a flat workpiece 36 containing a large number of short electrical pin intermediates 33 is obtained (
(See Figure 2 (D)).

Next, each processed body 36 moves to a polishing step 16 in which both main surfaces are polished using a known polishing means. A cross section of the workpiece 36 polished on both sides in this polishing step 16 is shown in FIG. 2(E). As is clear from this cross-sectional view, the workpiece 36 is made up of a number of electric pin intermediate bodies 33 of a certain length, each consisting of a copper wire 30, a tin plating layer 31, and a rack resin layer 32, which are mutually solidified by an epoxy resin layer 34. They are arranged at approximately constant intervals.

One main surface of the double-sided polished workpiece 36 is made conductive in a metallization step 17 (see FIG. 2(F)). Although a conductive paste 37 is applied in this preferred embodiment, the present invention is not necessarily limited to this, and any well-known metallization (conductivity) process can be applied.

Next, a tin etching step 18 is performed in which only the tin 31 exposed on the other (upper) surface of the workpiece 36 is selectively etched using an etching solution to form an annular groove 38 around the head 30a of the copper wire 30. (See Figure 2 (G)). The etchant may be any suitable etchant that etches only tin but not copper, such as borofluoric acid, but other well-known wet or dry etching techniques may be used.

The processed body 36 from which the head 30a of the copper wire 30 and the tin plating layer 31 around it have been partially removed and has a large number of annular grooves 38 is placed in an electroplating bath, and the conductive paste layer 37 is applied to one electrode and the copper plate. Copper plating step 19 with as the other electrode
Implement. Through this plating step 19, as shown in FIG.
A copper cap 39 is formed within the head 30a of the copper wire 30 and the annular groove 38 as shown in FIG.

Next, the surface on which the copper cap 39 is formed is polished in a polishing step 20.
The copper wire 30 is polished to a surface substantially flush with the surface of the head 30a of the copper wire 30. As a result, as shown in FIG. 2(I), the annular groove 3
A head portion 40 is formed in which portion 8 is filled with a copper plating layer. After the head portion 40 is formed, the conductive paste is removed.

Next, in a shellac melting step 21, the shellac resin layer 32 is melted from each electrical pin intermediate body 33 of the processed body 36. As a result, as shown in FIG. 2(J), a columnar body 41 made of tin-plated copper wire 30 having individual head portions 40 is obtained from the processed body 36, and a frame of epoxy resin 34 remains. Alcohol such as ethyl alcohol or ketones can be used to dissolve the shellac resin layer 32.

A tin plating stripping step 22 is performed in which this columnar body 41 is immersed in the etching solution as described above. Through this step 22, as shown in FIG. 2(K), a large number of electrical pins 42 with heads made of copper wires 30 and head portions 40 are obtained. Ni/
In the Au plating step 23, a nickel (Ni) layer 43 and a gold (Au) layer 44 are electrolessly plated on the entire surface of the electrical pin 42 (see FIG. 2(L)). This results in
An electrical pin 45 with a head plated with Ni/Au is obtained.

Next, an electric pin transfer step 24 is performed in which the electric pins 45 are inserted into a carbon jig 47 having an array of electric pin receiving openings 6 (see FIG. 2(M)).

The electric pins 45 inserted into the carbon jig 47 are made of gold (Au) and tin (Sn) brazing material formed on the glass substrate 50 in a separate process 25 to correspond to the array of electric pin receiving openings 46, which will be described later. A brazing material adhesion step 26 is performed in which the 51 pattern is adhered to the top portion including the head portion 40 of each electric pin 45 by thermal transfer. This step 26 is shown in FIG. 2(N).

The electric pin 45 to which the brazing material 51 is attached is heated and melted in a heating furnace (not shown) to form an arc-shaped all-tin brazing material 52 (see FIG. 2(O)). By taking out the electric pins 53 from this jig 47, a large number of electric pins 53 having the final shape shown in FIG. 2(P) can be obtained at the same time.

The electric pin 53 obtained in steps 10 to 27 described above is a T-shaped electric pin, that is, an electric pin having a head only at one end of the copper wire 30. However, it is of course also possible to obtain an I-shaped electrical pin with a similar head at the other end using some of the processes described above.

Next, with reference to FIGS. 3(A) and 3(B), a process of forming a patterned gold-tin brazing material 51 on the above-mentioned glass substrate 50 will be described.

FIG. 3(A) is a manufacturing process diagram using an electroplating technique. First, in a first step 60, a glass substrate 50 of a predetermined size, that is, a size corresponding to the carbon jig 47 described above, is prepared. In a gold (Au) deposition step 61, a gold layer that will become an electrode is deposited on one main surface of the glass substrate 50.

Thereon, a photoresist coating and patterning step 62 forms an exposed gold layer pattern corresponding to the electrical pin receiving openings 46 of the carbon jig 47.

A predetermined amount of gold (Au) and tin (Sn) are electroplated on the gold layer pattern exposed in the Au/Sn plating process 63.

The ratio of Au to Sn is generally 4:1.

The amount of plating depends on the size of the electrical pin. Finally, in a heating alloying step 64, this Au/Sn plating layer is heated to about 350° C. in a reducing atmosphere to alloy it.
/Sn brazing material 51 pattern is obtained.

On the other hand, FIG. 3(B) is another manufacturing process diagram. In the first step 70, a gold (Au) wire of a predetermined diameter is prepared. Next, in a conventional electroplating step 71, the outer circumference of the gold wire is uniformly plated with tin (Sn). The tin plating thickness is controlled to obtain a tin-plated gold wire with a gold to tin ratio of exactly 4:1. Next, in a slicing step 72, the plated gold wire is sliced into a predetermined length. In a transfer step 73, the sliced disk-shaped body is transferred into the recess of the carbon jig. Next, in a heating step 74 of heating in a reducing atmosphere, the gold/tin disk is heated to a temperature of, for example, 350
℃ to obtain a gold-tin brazing alloy. Finally, the all-tin alloy brazing material alloyed in the array fixing step 75 is applied to the glass substrate 5.
0 in a predetermined arrangement and fixed.

In the technique shown in FIG. 3(A), when the area of the glass plate is large, it is difficult to make the amount and ratio of gold and tin uniform over the entire surface. However, the technique of FIG. 3B results in a relatively uniform brazing material.

The method for manufacturing an electrical pin and the intermediate product of the electrical pin of the present invention have been described in detail above with reference to preferred embodiments. However, the present invention is not limited to such specific embodiments;
Those skilled in the art will readily understand that various modifications and changes can be made without departing from the spirit of the invention. That is, the greatest feature of the present invention is that an easily etched metal layer such as tin is formed on the outer periphery of a highly conductive wire such as copper by plating, and furthermore, a layer of easily etched metal such as shellac resin is easily dissolved in ethyl alcohol, etc. It consists in using an electrical pin intermediate coated with resin. Although shellac resin has been cited as a representative example of such easily soluble resin, similar effects can be obtained with vinyl acetate resin and the like.

〔Effect of the invention〕

As can be understood from the above description, according to the present invention, electrical pins coated with easily soluble resin such as shellac on the outer periphery of tin-plated copper wire are used, so that uniform electrical pins can be produced easily, quickly, and in large quantities. It has the remarkable effect of being easily manufactured. In addition, well-known technology and equipment can be used in the manufacturing process,
Etching and dissolving do not require the use of chemicals that are hazardous to humans or the environment. Furthermore, since the brazing material is transferred to the head of each electrical pin at the same time, it is possible to uniformly coat a large number of electrical pins with the brazing material at the same time.

[Brief explanation of the drawing]

Figure 1 is a process diagram for manufacturing an electrical pin according to the present invention, and Figure 2 (A
) to (P) are explanatory diagrams of the main steps in FIG. 1, and FIGS. 3 (A) and (B) are diagrams of the manufacturing process of the patterned gold-tin brazing material used in the electrical pin of the present invention. 30...Good conductive rod-shaped body 31...Etchable metal layer 32...Easily soluble resin layer 33...Electric pin intermediate body 53...Electric pin

Claims (2)

[Claims] 1. A method for manufacturing an electrical pin in which a large number of electrically conductive rods of a predetermined length are arranged, fixed with a resin, and then sliced into desired lengths to obtain a large number of electrical pins at the same time. 1. A method for manufacturing an electrical pin, comprising the step of forming an etched metal layer and an easily soluble resin layer such as shellac on the outer periphery before fixing the pin. 2. An electrical pin intermediate used for simultaneously manufacturing a large number of electrical pins by fixing a large number of electrically conductive pins with resin, which comprises an etching metal layer and shellac on the outer periphery of a highly conductive wire. An electrical pin intermediate characterized by being provided with an easily soluble resin layer such as.