络合剂对次磷酸钠印制线路板化学镀铜的影响

he influence of complex agents (edetate disodium, potassium sodium tartrate) on the stability of the bath containing sodium hypophosphite and the electroless Cu-plating rate was investigated. Then, the electrochemical properties of the Cu- coating were examined by means of linear sweep and cyclic voltammetry. The results show that with addition of EDTA2Na, the cathodic reduction peak current increases and the anodic oxidation peak current changes less; with the increase of potassium sodium tartrate the cathodic reduction peak current and anodic oxidation peak current first increases and then decreases; both of EDTA2Na and potassium sodium tartrate can improve the stability of electroless plating bath and the quality of Cu coatings, of which the former reduced, while the later increased initially and then decreased the plating rate; correspondingly the appropriate dosages are 12 and 9.6 g/L, respectively for the two complex agents.