JPS6340210A - Conducting composition for electronic component electrode - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a conductive composition used for forming electrodes for electronic components, and more particularly.

The present invention relates to a conductive composition suitable for forming multilayer wiring circuit ceramic cutting boards and lead electrodes of multilayer capacitors.

[Conventional technology]

Electronic components such as multilayer wiring circuit ceramic boards and multilayer capacitors are produced by printing electrodes and wiring patterns on ceramic sheets whose main ingredients are alumina, barium titanate, etc. with a conductive paste containing Ni as a conductive material, and then reducing these. It is made by firing in an atmosphere. The electrodes formed on the ceramic sheets can be roughly divided into those that are placed inside the laminated ceramic sheets and those that are exposed on the surface of the ceramic sheet for connection to an external conductor. . The former are called internal electrodes, and the latter are called extraction electrodes. Of these, the latter lead-out electrode is made after firing in order to improve solderability with external conductors.

The surface is plated with Ni or covered with solder chips.

[Problem that the invention seeks to solve]

However, in the above-mentioned lead-out electrode, when a conductive paste is co-fired with a ceramic sheet and Ni plating is applied to the surface by an electroless plating method, the adhesion of the plating film is poor. For this reason.

Even when soldering was performed on the plating film, there were problems in that the solderability was poor and the adhesion strength was weak.

An object of the present invention was to solve the above-mentioned problems with conventional conductive materials.

The object of the present invention is to provide a conductive composition capable of forming an extraction electrode with good plating film adhesion in the Ni agate process after firing.

[Means to solve the problem]

That is, the conductive composition according to the present invention has Li of 0.6 to
6.2at%, and the balance is Ni.

〔Example〕

Next, specific embodiments of the present invention will be described.

(Example 1) 90.1g of Ni powder with a purity of 99.9% and a purity of 99.9%
%L, 12cO3 powder and ethyl cellulose.

114g of binder whose main ingredient is butylcarpitol
were mixed using a lightning crusher for 3 hours, and then kneaded using a roll mill for 1 hour to produce a conductive paste.

Separately, an unfired multilayer ceramic capacitor body was prepared by coating and laminating a conventionally known Ni paste on a l3aTiO3 ceramic green sheet. The above-mentioned conductive paste is dip-coated on both ends and the periphery of both ends of this unfired multilayer ceramic capacitor body, and then
It was dried by applying a temperature of 00° C. for 30 minutes.

This was then fired with the following profile.

First, in an N2 gas atmosphere containing 2% H2 gas, the temperature was raised to a maximum of 1200°C at a heating rate of 100°C/hr.
This temperature was maintained for 2 hours. After that, the temperature decrease rate is 300℃
/ hr to room temperature. The lead electrode of the multilayer ceramic capacitor thus fired has an Li content of 2.
1 at% and 97.9 at% of Ni.

800 such multilayer ceramic capacitors were
Divide into 4 groups of 0 pieces each, and each group is coated in a commercially available electroless nickel plating bath for 5 minutes, 10 minutes, 15 minutes, and 2 minutes.
It was printed for 0 minutes at a time. 200t of each of these groups [
Visually observe the extraction electrodes of lil's multilayer capacitors, and the group where the Ni plating film is deposited on the entire surface is O, the group where the Ni plating film is not deposited on some parts is △, and the total <N
Samples in which no i-MEC film was precipitated were marked as x, and the results are shown in Table 1.

(Example 2) In Example 1, 93.1 g of Ni powder was used instead of 90.1 g of Ni powder.
An extraction electrode was formed using the same method and conditions as in Example 1, except that 8 g was used, and 6.2 g was used instead of 9.9 g of l,12cO3 powder, and Ni was electrolessly plated on this. Table 1 shows the results of similarly examining the condition of the plating film.

Note that the extraction electrode contains 1.2 at% Li.

It consisted of 98.8 at % of Ni.

(Example 3) In Example 1, 75.1 g of Ni powder was used instead of 90.1 g of Ni powder.
An extraction electrode was formed using the same method and conditions as in Example 1, except that 2 g was used, and 24.8 g was used instead of 9.9 g of [,12cO3 powder, and Ni was electrolessly plated on this. Table 1 shows the results of similarly examining the condition of the plating film.

Note that the extraction electrode contains 6.2 at% Li.

It consisted of 93.8 at% Ni.

(Example 4) In Example 1, 96.1 g of Ni powder was used instead of 90.1 g of Ni powder.
8g, and 3 instead of 9.9g of Li2CO3 powder.
．． An extraction electrode was formed using the same method and conditions as in Example 1, except that the plating time was 2g, and the plating time was divided into 10 minutes, 15 minutes, 20 minutes, and 25 minutes.
Electroless plating of i.

Table 1 shows the results of similarly examining the condition of the plating film.

Note that the extraction electrode contains 0.6 at% Li.

It consisted of 99.4 at% Ni.

(Comparative example) In Example 1, Ni
100g of powder was used and the plating time was 20
An extraction electrode was formed using the same method and conditions as in Example 1, except that the test was carried out separately for 25 minutes, 25 minutes, 30 minutes, and 35 minutes.Ni was electrolessly plated on this electrode, and the condition of the plated film was similarly examined. The results are shown in Table 1.

Note that the above-mentioned extraction electrode was made of 99.9 at% Ni.

As is clear from the above Examples and Comparative Examples.

Table 1 In the examples of the present invention, a lead electrode was obtained in which the Ni plating film was well spread over the two surfaces and a Ni plating film with high adhesion strength could be formed in a short time.

Note that the proportion of Li in the conductive composition is 0.6 to 6.2.
The reason for limiting the Li content to at% is that whether the Li content is higher or lower than this, the adhesion of Ni plating to the extraction electrode will deteriorate, and there will be a noticeable difference compared to when conventional conductive paste is used. This is due to the fact that it is not recognized.

〔Effect of the invention〕

As explained above, 9 According to the present invention, the adhesion of the Nt plating film by the electroless method to the extraction electrode of electronic components is good (thereby, it is possible to provide the extraction electrode with an adhesion strength equal to or higher than that of the conventional method in a short time). This has the effect of being able to apply a Ni plating film having the following characteristics.

Inventor Takashi Sotomaru

Claims (1)

[Claims] A conductive composition for an electrode of an electronic component comprising 0.6 to 6.2 at% of Li and the balance being Ni.