JPH0424853B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to cylindrical capacitors, multilayer capacitors,
Alternatively, the present invention relates to a method of forming electrodes on the body of an electronic component such as a resistor.

<Prior art> Conventionally, as a method for forming electrodes of this type of electronic component, as shown in FIG.
A method is known in which the end portion 21a of the electronic component body 21 is immersed in the liquid, the electrode material 20a is attached to the same end portion 21a, and then the electrode material 20a is solidified.

<Problems to be Solved by the Invention> However, in the above method, after the end portion 21a of the electronic component body 21 is pulled up from the electrode material liquid 20, until the electrode material 20a is solidified, the remaining particles adhered to the end portion 21a. The electrode material 20a is fluidized, and its film thickness is
As shown in FIG. 5, the thickness increases from the top to the bottom at the side surface A of the end 21a, and from the periphery toward the center at the bottom B of the end 21a.

For this reason, the expensive electrode material 20a is consumed unnecessarily, and unreasonable internal stress is generated when the electrode material 20a solidifies, causing the electrode material 20a to turn over or break at the corner of the end, so-called membrane peeling. Edge breakage sometimes occurred.

Furthermore, when a cap is fitted on the outside of the electrode material 20a, problems may arise in fitting the cap.

Therefore, as a solution to this inconvenience, after attaching the electrode material 20a to the end 21a of the electronic component main body 21 by the same method as described above,
As shown in the figure, the electrode material 20 attached to the end 21a
It was considered that the excess portion of the electrode material 20a could be transferred to the surface plate 22 by bringing the hanging portion of a into contact with the upper surface 22a of the surface plate 22.

According to this method, as shown in FIG. 7, the film thickness at the lower end B of the electrode material 20a becomes almost uniform, but a certain film thickness gradient still remains at the side surface A, and the electrode material 20a becomes excessively thick. Because it adheres,
A drastic solution was impossible.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for forming an electrode for an electronic component that can form an electrode having a substantially uniform thickness from the end face to the circumferential surface of the electronic component main body.

<Means for solving the problems> In order to achieve such an object, the present invention has the following features:
A process of immersing the end of the electronic component body into a paste-like electrode material layer set to a predetermined thickness level, attaching the electrode material to the end, and pulling up the electronic component body with the electrode material attached. The step is to hold only the lower end of the end in contact with the surface of the electrode material layer, and after lifting the electronic component body from the electrode material layer, the hanging part of the electrode material attached to the end is held on a surface plate. and a step of bringing it into contact with the upper surface.

<Example> Hereinafter, an example of the present invention will be described based on the drawings.

Figures 1a to 1j show a method for forming external electrodes of a chip-type electronic component according to an embodiment of the present invention.
This method is carried out in the following steps.

As shown in FIG. 1a, the horizontal upper surface 1a of the substrate 1
The electrode material layer 2 is formed by uniformly applying a paste-like electrode material 2a to a predetermined thickness level h. This electrode material layer 2 is formed by supplying the electrode material layer 2a onto the substrate 1 and smoothing the surface with a squeegee blade (not shown).
The thickness is set to a predetermined thickness h. This thickness level h
is set corresponding to the length l of the external electrode (see FIG. 3) 2e formed on the end 4a of the electronic component body 4. The electrode material 2a is mainly made of silver, for example, and contains palladium to prevent silver from diffusing into the solder during soldering.

As shown in FIG. 1a, the end portion 4a of the electronic component body 4 positioned on the electrode material layer 2 is moved as shown in FIG. 1b.
As shown in FIG.
Attach a.

As shown in FIG. 1c, the end 4 of the electronic component body 4
a onto the surface portion 2b of the electrode material layer 2. At this time, as explained in FIG. 5, the thickness of the electrode material 2a attached to the end 4a is from top to bottom at the side surface A, and from the periphery to the center at the bottom end B. Each one is getting thicker.

As shown in FIG. 1d, the end 4 of the electronic component body 4
While transferring the lower end 4b of a to another position of the electrode material layer 2, that is, the flat surface portion 2b of the electrode material layer 2, the surface portion 2b is moved as shown in FIG. 1e.
and temporarily maintain that state. As a result, the electrode material 2a attached to the side surface A of the end portion 4a adapts to the surface portion 2b of the electrode material layer 2 due to the surface tension of the electrode material 2a, and the excess electrode material 2a is absorbed into the material layer 2 side. Figure 1 f
As shown in the figure, the film thickness is almost uniform in the vertical direction.

Here, the position of the lower end 4a of the electronic component body 4 does not have to exactly match the position of the surface portion 2b of the electrode material layer 2, and as shown in FIG. 2 surface portion 2b
A dimensional error S of about 20% of the height H of the electrode material at the side surface A is permissible. Also, Figure 1 d
The state of the electrode material layer 2 may be the same as that of the electrode material layer 2 shown in FIG.

As shown in FIG. 1g, the electronic component main body 4 is pulled up and the electrode material 2a attached to the end portion 4a is separated from the surface portion 2b of the electrode material layer 2. In this state, the electrode material 2a hanging down from the lower end 4b of the electronic component main body 4 still becomes thicker from the periphery toward the center.

By lowering the electronic component main body 4 shown in FIG. 1g on the surface plate 5 as shown in FIG. 1h, the end 4
Hanging portion 2c of electrode material 2 attached to a
is brought into contact with the horizontal upper surface 5a of the surface plate 5 in the vertical direction as shown in FIG. 1 h to i. As a result, as shown in FIG. 1j, the excess portion 2d of the hanging portion 2c of the electrode material 2a is transferred to the surface plate 5,
The film thickness at the lower end 4b is approximately equal. In addition,
The process is repeated two or more times as necessary.

The electrode material 2a of the electronic component main body 4 that has gone through the process shown in FIG.
An external electrode 2e is obtained which almost evenly covers the side surface portion A and the lower end portion B of.

In order to form the external electrodes 2e on both ends of the electronic component body 4, the above-mentioned steps 1 to 3 are performed on the other end of the electronic component body 4.

Note that after the step shown in FIG. 1b, it is possible to skip to the step e shown in FIG. 1 without going to the step shown in FIG. 1c. In other words, after the step shown in FIG. 1b, the lower end 4b of the electronic component body 4 is removed from the electrode material layer 2 as shown in FIG. The electrode material 2 of the end portion 4a can also be removed by pulling it up close to the surface portion 2b and temporarily maintaining that state.
a can be formed into the state shown in FIG. 1f.
However, in order to obtain the external electrode 2e with a clean surface, it is preferable to go through the steps b→b→d→e, as described above.

Furthermore, the following steps may be repeated multiple times.

<Effects of the Invention> According to the method for forming electrodes of electronic components of the present invention, after attaching the electrode material to the end of the electronic component body,
By holding the lower end of the end in contact with the surface of the electrode material layer, the thickness of the electrode material layer on the circumferential surface of the end of the main body is approximately equalized, and the electrode attached to the end of the main body is By bringing the hanging portion of the material into contact with the upper surface of the surface plate, the thickness of the electrode material layer on the lower surface of the end portion of the main body can be approximately equalized. That is, there is an effect that an external electrode having a substantially uniform thickness can be formed at the end of the electronic component main body from the end surface to the circumferential surface.

[Brief explanation of drawings]

1A to 1J are process diagrams of a method for forming electrodes of an electronic component according to an embodiment of the present invention, and FIG.
Figure e is an explanatory diagram, Figure 3 is an explanatory diagram of the external electrode, and Figure 4 is an explanatory diagram of the external electrode.
The figure is a first explanatory diagram of the conventional method, FIG. 5 is an explanatory diagram showing the adhesion state of the electrode material based on the conventional method of FIG. FIG. 2 is an explanatory diagram showing the state of attachment of an electrode material based on the conventional method shown in the figure. 2... Electrode material layer, 2a... Electrode material, 2b...
...surface portion, 2c... hanging portion, 4... electronic component body, 4a... end, 4b... lower end, 5... surface plate, 5a... upper surface.

Claims (1)

[Claims] 1. Dip the end of the electronic component body into a paste-like electrode material layer set to a predetermined thickness level,
A step of attaching an electrode material to the end of the electronic component, a step of pulling up the electronic component body with the electrode material attached and holding only the lower end of the end in contact with the surface of the electrode material layer, and a step of attaching the electronic component body to the electrode material layer. A method for forming an electrode for an electronic component, comprising the step of bringing a hanging part of an electrode material attached to an end of the electrode material into contact with the upper surface of a surface plate after being lifted from the layer.