JPH02291000A - Production of electronic part - Google Patents

Abstract

PURPOSE:To improve the current applicability to a material to be plated and to Produce the plated material having a uniformly thicknessed plating layer in good yield at the time of barrelplating many small chip-shaped electronic parts by mixing dummy chips of specified size with the materials to be plated in the barrel. CONSTITUTION:Many small-sized electronic parts 5 are placed in the hexagonal cylinder-shaped barrel 6 having many slits and mixed with two kinds of dummy chips 11 and 12 of different sizes. The barrel is rotated in the plating soln. 2, a negative voltage is impressed on the part 5 in the barrel 6 by a cathode bar 7 through the dummy chip, and a current is applied between the part and an anode to form an electroplating layer on the surface of the part 5. In this case, the first dummy chip 11 smaller than the part 5, the second dummy chip 12 having a size close to that of the part 5 and the part 5 are mixed in the volume ratio of 1:2:2. The current applicability to the part 5 from the cathode 7 by the rotation of the barrel 6 is improved by the presence of the dummy chip, and a plating layer is uniformly formed on many small-sized electronic parts.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method of manufacturing electronic components such as multilayer ceramic capacitors and chip resistors, and more specifically, a method of manufacturing electronic components such as a multilayer ceramic capacitor and a chip resistor. This invention relates to a plating method with improved plating growth efficiency.

[Conventional technology]

Electronic components such as multilayer ceramic capacitors, chip resistors, multilayer varistors, etc. are treated in batches using liquid processing equipment as shown in the partially cross-sectional front view of Figure 2. In the figure, (1) is a processing tank in which a large number of processing tanks are arranged in a row, and a plating solution (2) and the like are stored therein. (3) is
A carrier that moves horizontally and vertically above the processing tank (1), and at the lower end of the arm (4) that moves up and down,
It is equipped with a rotating hexagonal cylindrical barrel (6) that accommodates a large number of chip-shaped electronic components (5). A slit (6a) is formed on the circumferential surface and side surface of the barrel (6).
6) is immersed in the plating solution (2), the plating solution (2) is allowed to infiltrate into the barrel (6).

(7) is a cathode electrode bar that penetrates the inside of the barrel (6) and also serves as a rotational support shaft, and an anode bar (not shown) located at a distance from the barrel (6) enables plating. A mesoelectric current is applied to the solution (2).

Note that the electrodes, which are the plating parts of the electronic component (5), are simply coated with Ag paste, etc. at both ends of the electronic component (5), and the rest of the part is insulated, so no plating current flows through the electrodes. Since it is hard to use, a spherical iron dummy chip (10) is mixed together with the electronic component (5) in the barrel (6), and the electrode, which is the plated part of the electronic component (5), is placed in the spherical dummy chip (10). The electrode bar (7) is energized through the electrode bar (7) so that a sufficient plating current flows through the electrode bar (7).

The liquid processing device is configured as described above, and then the electronic components (
5) The plating method will be explained.

First, a barrel (6) containing an electronic component (5) and a spherical dummy chip (lO) is placed in a plating solution (1) in a processing tank (1).
2) To? +? M. Then, the barrel (6) is rotated while applying electric current using the electric bar (7). Then, the electronic component (5) becomes a spherical dummy chip (10)
At the same time, the electric rod of the electronic component (5) is transferred within the barrel (6), and electricity is applied to the electrode bar (7) via the spherical dummy chip (10), thereby forming plating. The plating process is
After being carried out multiple times in a plurality of processing tanks (1), the process is finished by being washed with water in a processing tank containing washing water.

(Problem to be Solved by the Invention) If the electronic component (5) has a relatively small external shape of 1 m x 2 m to 2 x 3 fl, the diameter is 1.2 to 1.7 fl.
Two to four times as many spherical dummy chips (10) as the electronic components (5) are mixed. By mixing a spherical dummy chip (10) that is slightly smaller in size than the electronic component (5), the electrode of the electronic component (5) comes into contact with the electrode bar (7) via the spherical dummy chip (10). , it becomes energized and a uniform plating thickness can be formed.

However, when the external size of the electronic component (5) is relatively large, such as 3 mm x 4 m, the electronic component ( 5) The spherical dummy tip (10) falls from the gap between the holes and concentrates on the bottom of the barrel (6), causing a shortage of the spherical dummy tip (10), and the electric groove of the electronic component (5) contacts the electrode bar (7). In some cases, the condition may not be reached. As a result, the electrical conductivity becomes non-uniform, resulting in a uniform thickness between the electronic components (5) housed in one barrel (6) and between the electronic components (5) housed in another barrel (6). It becomes impossible to form a plating layer.

On the other hand, the diameter is 2.4 to 3.5 mm so that it does not get into the gap between the electronic components (5). Otm's large spherical dummy chimp (
10), on the other hand, the electronic component (5) is placed above the rotation axis of the barrel (6), and the spherical dummy chip (10)
Concentrate more downward. Since the plating current tends to flow to the upper part of the rotating shaft of the barrel (6), that is, to the part in contact with the plating liquid, more plating is applied to the spherical dummy chip (10), which reduces the plating growth efficiency of the electronic component (5) and causes plating. This results in a problem that it takes a long time.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for manufacturing an electronic component that has good electrical conductivity and high plating growth efficiency.

[Means to solve the problem]

In order to achieve the above object, the present invention has a plurality of sizes when mixing a large number of chip-shaped electronic components and dummy chisop in a predetermined ratio and barrel plating, each type having a size larger than the above-mentioned electronic component. A small dummy chisel, one of which has a size close to that of an electronic component, and the electronic component are mixed at a predetermined ratio and then barrel-mixed.

[Effect]

By using multiple types of dummy chips smaller than the electronic components, the electronic components are electrically connected regardless of their position in the barrel, and the plating current flows with good conductivity to the electronic components immersed in the plating solution. Since less plating occurs, the growth efficiency of plating becomes higher.

〔Example〕

An embodiment of the present invention will be described with reference to a partially sectional side view of a liquid processing apparatus shown in FIG.

However, parts that are the same as before are given the same reference numerals and their explanations will be omitted. In the figure, (11) and (12) are first and second dummy chips smaller than the chip-shaped electronic component (5), for example, the electronic component (5) has a size of 3 dragons x 4 H. In this case, the first dummy tip (1l) has a diameter of 1.2 to 1.7 nm, and the second dummy tip (12)
The diameter is 2.4 to 3. Otm electronic components (5)
Use one with a size close to . And career (6)
When storing electronic components (5) with a capacity of 125 cc inside, the first and second dummy chips (11) (12
) both store a capacity of, for example, 240 cc,
Electronic component (5) and first and second dummy chips (11) (
12) in a ratio of approximately 1:2:2.

Such first and second dummy chips (11) (12)
and the carrier (6) containing the electronic components (5) are immersed in the plating solution (2) in the treatment tank (1). Then, while applying plating current through the electrode bar (7), the barrel (6
), the first and second dummy chips (11)
(12) and electronic components (5) are transferred within the barrel (6). The electronic components (5) are densely distributed at the bottom of the barrel (6) and become coarser in the upper direction of rotation, but the smaller first dummy chips (11) gather at the bottom of the barrel (6) and the larger The second dummy chimp (12) gathers upward in the direction of rotation. Therefore, conveniently, the first dummy chip (11) contacts the electrodes of the dense electronic component (5), and the second dummy chip (12) contacts the coarse electronic component (5) to mix uniformly. . As a result, the first
The electronic component (5) is reliably energized through the second dummy chips (11) and (12), and plating with a uniform thickness can be formed.

In addition, as a result of the experiment, we found that 3 m x 4 y electronic components (5
) and a second dummy tip (12) with a diameter of 2.4 fins, the first dummy tip (11) with a diameter of 1.5 fins and the second dummy tip with a diameter of 2.7 fins dummy chip (
It was found that when the two types 12) were mixed, the electronic component (5) was plated more than the first and second dummy chips (11) and (12).

The above describes one embodiment according to the present invention, and the present invention is not limited to this embodiment, and the design can be changed within the gist of the present invention. The size and type of chips or their mixing ratio can be changed as appropriate.

〔Effect of the invention〕

According to the present invention, by mixing a plurality of types of dummy chips in the barrel, it is possible to improve the conductivity of electricity to the electronic component and form plating with a uniform thickness. Also,
Since less plating is applied to the dummy chip, the plating growth efficiency is improved, the plating time is shortened, and workability is improved.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view of a liquid processing apparatus embodying the present invention, and FIG. 2 is a partially sectional front view of a conventional liquid processing apparatus. (1) One treatment tank, (2) One plating solution,
(5) One electronic component, <6> One barrel, (11) one first dummy chip, (12) one second dummy chip.

Claims (1)

[Claims] (1) When barrel plating a large number of chip-shaped electronic components and dummy chips mixed at a predetermined ratio, they have multiple sizes, each of which is smaller than the electronic components mentioned above, and One type of electronic component manufacturing method is characterized in that a dummy chip having a size close to that of an electronic component and the electronic component are mixed at a predetermined ratio and barrel plated.