Effect of SPS Adsorption on the Copper Electrodeposition in Acid Copper Sulfate Bath

摘要

In general, copper electrodeposition from acid copper sulfate bath is carried out with additives such as polyethylene glycol (PEG), chloride ion (Cl~-), and bis (3-sulfopropyl) disulfidedisodium (SPS). In this study, the effects of PEG and Cl~- on the SPS adsorption were investigated. The amount of adsorption of SPS was confirmed to be remarkable in the bath containing both additives, and the amount of SPS was found to depend on the coverage of PEG. The copper deposition from the bath with the additives was considered to proceed by one-electron two-steps reaction via CuCl as an intermediate. The Cole-Cole plots showed that the adsorbing SPS prevents the local crystal growth of copper.