Potential low‐cost palladium‐alternatives for activating electroless copper deposition

Abstract

PurposeThe purpose of this paper is the investigation of the catalytic activities of selected metals in reductant oxidation.Design/methodology/approachElectrochemical measurements were carried out in order to obtain information about the catalytic activity of copper, silver, nickel, and palladium in the oxidation reactions of formaldehyde and glyoxylic acid.FindingsMetals with high‐catalytic activity for each reductant oxidation can be determined by using cyclic voltammetry. These metals are suitable for an improved activation process in electroless copper deposition. Electrochemical measurements show that palladium does not have the highest catalytic activity of all tested metals. Therefore, alternative and inexpensive metals are explored as catalysts in electroless copper plating reactions.Research limitations/implicationsAt the present time, formaldehyde is the established reducing agent in the electroless copper metallization of plated through‐holes. Because of its environmental impact, there is a need to replace formaldehyde. A change in reducing agent can lead to a change in the activation process, because there is no one metal that appears to be a good catalyst for the oxidation of all reducing agents that have been employed for electroless deposition. This paper suggests that further improvement in electroless copper plating processes may be possible with an alternative activation procedure that yields higher catalytic activity.Originality/valueBased on the results of experiments, the development and optimization of activation processes in electroless copper plating can be advanced.