Mfg. method of electronic parts and siad electronic parts, electroless coating method

Abstract

A work piece is mixed with Ni pieces having an average diameter of 1 mm and exhibiting catalytic activity to oxidation reaction of sodium phosphinate (NaH2PO2) added as a reducing agent in a plating bath containing the reducing agent and a Ni salt to form a Ni-P film on an electrode made of Cu, Ag or Ag-Pd by auto-catalytic electroless plating. Then, the work piece is dipped in a plating bath containing an Au salt to form an Au film on the surface of the Ni-P film by substitutional electroless plating. This method is capable of forming a desired plating film only on a desired portion at a low cost.

Description

technical field [0001] The present invention relates to a method for manufacturing electronic components, an electronic component, and an electroless plating method, and particularly to a method for manufacturing substrate-type electronic components such as multilayer capacitors and noise filters, and electronic components manufactured by applying the manufacturing method. Background technique [0002] In the field of electronic components, in order to improve the performance of adhesion and solderability, conductive resin adhesion, heat resistance, corrosion resistance, etc., to obtain high-performance electronic components with high reliability, nickel or gold plating is widely performed on the electrode surface . [0003] However, when classified according to the coating method, it is well known that the plating method can be roughly divided into electroplating and electroless plating in which a current is passed through a plating solution containing metal ions to perform...

AI Technical Summary

Problems solved by technology

That is, from an economic point of view, it is desirable to place cheap steel balls with inconsistent shapes in a barrel plating device for plating treatment. However, with the miniaturization of electronic components, the hole diameter of the barrel has to be reduced. As a result, Since the conductive media will be caught by such small-diameter holes, only high-priced small-diameter conductive media and steel balls with the same shape can be used, resulting in increased production costs.

[0012] (3) In addition, in the case of forming Au plating film by barrel plating method, since Au is covered not only on the electrodes of electronic components, but also on the conductive medium, the consumption of expensive Au exceeds its necessary amount, especially in the case of plating by bonding method. In the case of Au, the film thickness must be increased, leading to an increase in production cost

[0014] On the other hand, in the electroless plating method disclosed in Japanese Patent Application Laid-Open No. 10-135607, the Pd catalyst is attached to the surface of the electrode, and the plating process can be performed, so it is possible to form only the desired plating film on the electrode.

However, for example, it may not be possible to maintain sufficient adhesion between the Ni-b layer and the Au layer, so it is necessary to form a Ni-P layer with good adhesion to Au on the surface of the Ni-B layer.

Therefore, two coating layers must be formed between the electrode and the Au layer, that is, the Ni-B layer and the Ni-P layer, and the manufacturing process is complicated, which is a problem

And, when electroless plating forms Ni-B coating film, usually must use dimethylamine borane [(CH 3 ) 2 NHBH 3 ; Hereinafter referred to as "DMAB"] and other high-priced reducing agents, the increase in production costs is also a problem

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