고압 매크로에멀젼을 이용한 전해도금에 관한 연구

Abstract

In this study, the supercritical electroplating was investigated by forming macroemulsion of electroplating solution using surfactant in supercritical CO2. The fluorinated analogous AOT surfactant, sodium salt of bis (2,2,3,3,4,4,5,5-octafluoro-1-pentanol) sulfosuccinate which has both ‘CO2 philic’ chains and ‘hydrophilic’ head group was used as a surfactant, and Ni plate and Cu plate were used as the anode and the cathode, respectively. Electroplating was carried out in the conventional method and the supercritical macroemulsion and both results were compared. The supercritical electroplating was carried out in various concentration of surfactant such as 2, 4, 7 wt%, the volume ratio of Ni-plating solution to CO2 was varied in the range of 10-70 vol%, and propane was used as a supercritical fluid instead of CO2. According to the experimental results, the plated surface of Ni on Cu plate performed in supercritical macroemulsion was better than that, in conventional state. In the image of Ni surface plated on Cu plate in supercritical state, there were fewer pin-holes and pits comparing with that in the conventional process. The current and conductivity was increased as the volume ratio of Ni-plating solution to CO2 was increased and the current and the amount of Ni plated on Cu plate were decreased as the concentration of surfactant become higher. In addition, in case of the continuous phase, using CO2 was more effective than using CO2.