Nonelectrolytic gold plating liquid and method thereof

Abstract

Electroless gold plating baths and plating methods using these baths are provided. The electroless gold plating bath includes i) water-soluble gold compound, ii) complexing agent that stabilizes gold ions in the plating bath, but does not cause substantial dissolution of nickel, cobalt or palladium in the plating bath, and iii) a polyethyleneimine compound. When a material to be plated is subjected to such a gold plating bath, corrosion of the base metal under the surface of the material to be plated is reduced by controlling the substitution reaction rate immediately after initiation of the reaction, and adhesion between the base metal and deposited gold coating is increased.

Description

technical field [0001] The present invention relates to an electroless gold plating solution and an electroless gold plating method used when forming a gold plating coating on parts used in the electronics industry, such as printed circuit boards or indium tin oxide (ITO) substrates. In particular, the present invention relates to such an electroless gold plating solution and method, whereby base metal erosion or corrosion is very slight when gold is deposited on the material to be plated, thus resulting in good adhesion, as well as good weld strength of gold film. Background technique [0002] Conventionally, gold plating has been used on the surface of electronic parts, such as printed circuit boards, ceramic integrated circuit ("IC") packages, ITO substrates and IC cards, to improve chemical resistance, oxidation resistance and physical properties, such as metal conductive performance, welding performance, thermocompression bonding performance and other connection perfor...

AI Technical Summary

Problems solved by technology

However, the conventional electroless gold plating technique has serious problems in terms of producing substandard products due to insufficient solder bonding strength

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