Some recent topics in gold plating for electronics applications

Abstract

A review is presented of selected recent topics in electrolytic and electroless gold plating for electronics applications. The topics covered include developments of non-cyanide electroplating baths for plating soft gold suitable for fabricating microbumps on silicon wafers, electroplating of hard gold and alternative materials with thermally stable electrical contact resistance and wear resistance for use on connectors exposed to elevated temperatures, and neutral, non-cyanide electroless processes for plating pure, soft gold on isolated areas of circuit boards. The development of the new electroless processes has been a subject of great interest and activity, and therefore an extensive survey of the progress in this field is included.

Significance of inclusions in electroplated gold films for electronics applications

“…All of these properties are influenced greatly by inclusions. Recently this author reviewed those issues in detail elsewhere (48,51), and therefore only very brief descriptions will be given below.…”

Broadband infrared absorption enhancement by electroless-deposited silver nanoparticles

“…In this article, we report an alternative approach of mass fabrication of silver NPs on top of the semiconductor interface, which is known as the electroless deposition of metal. Electroless plating has attracted great interest due to the simplicity of operation, costeffectiveness, high throughput, and the limited requirements of elaborate equipment [47,48]. Over the last few years, in contrast to complex and expensive vacuum methods of metallization, electroless deposition, as an alternative to colloidal solutions and self-assembly techniques, has also been used as a worthwhile method for the fabrication of metallic NPs on different surfaces [49][50][51][52].…”

Effect of a hard sublayer on contact interaction and wear behavior of electrodeposited gold-based coatings

“…Such coatings must have high chemical and corrosion resistance, electrical conductivity, as well as low and stable contact resistance. To improve the wear resistance of Au coatings they are usually alloyed with small additions (<1 wt.%) of Ni or Co [3]. Introduction of alloying elements increases the coating hardness due to their segregation at the grain boundaries without significant impact on the electrical conductivity of the coatings.…”