Clarifying the mechanism of actions of suppressor, brightener and sodium chloride in acid copper electrodeposition: A multidisciplinary approach for a many variable problem

Acid copper (AC) electrodeposition still a cardinal process for many fields, from electronic to decorative industries. Moreover, AC electroplating is a necessary step for Ni-free production cycles which are trending given the increased awareness of the toxicity of Ni2+ salts. State-of-the-art AC baths are formulated with a set of three organic additives, which are needed to achieve coatings with proper mechanical and optical features. However, despite the widespread use of these substances, their mechanism of action and the role of NaCl during the deposition are not clearly defined. A multidisciplinary approach has been employed to obtain insights on the mechanism of action of the organic additives on the Cu surface. This approach is based on electron microscopy electrochemical analysis supported by X-ray based techniques and computational calculations and simulations. An electrical field was included in molecular dynamics to delve the interactions between active species within the electrodeposition.