Bright nickel film deposited by supercritical carbon dioxide emulsion using additive-free Watts bath

• DOI: 10.1016/j.electacta.2010.06.037
• Publication Date: 2010-06-21T00:24:51Z
• Authors: Tso-Fu Mark Chang; Masato Sone; Akinobu Shibata; Chiemi Ishiyama; Yakichi Higo
• Keywords: Supercritical Carbon Dioxide; Plating (geology)

Abstract This paper is aimed on studying film smoothening effect of supercritical carbon dioxide emulsion (Sc-CO 2 -E) on nickel film electroplated using an additive-free Watts bath. Morphology of nickel film electroplated with Sc-CO 2 -E was found to be similar to that of nickel film prepared from electroless plating. Surface roughness ( R a ) of nickel film electroplated with Sc-CO 2 -E was lower than that of nickel film electroplated through conventional method. A minimum R a was found for nickel film electroplated through conventional method and Sc-CO 2 -E when increasing current density from 0.010 to 0.150 A/cm 2 . The minimum R a was 69.8 nm at 0.020 A/cm 2 and 14.0 nm at 0.030 A/cm 2 , respectively for conventional and Sc-CO 2 -E case. After the minimum point, increasing rate of R a increased was lower for Sc-CO 2 -E case; this was because of higher hydrogen solubility in Sc-CO 2 . Grain size of nickel film electroplated with Sc-CO 2 -E was found to be finer than that of conventional case.