トリエタノールアミン浴からの無電解銅めっきに及ぼす添加剤の作用

抄録

In a study of the effect of 2-2'-bipyrizyl (bipy) and potassium ferrocyanide (ferro) on the plating of copper in Cu-triethanolamine (TEA) solution, we found that in a bath of high Cu concentration (0.06M) with a low TEA/Cu ratio (=7/6) (Bath A), bipy accelerated the oxidation of formaldehyde cooperating with the Cu-TEA complex, which resulted in a high plating rate but in poor adherence and smoothness.
In a bath of a lower Cu concentration (0.03M) with higher TEA/Cu ratio (=5) (Bath B), bipy showed a fine leveling effect with diminuation of the accelerating effect. These effects were explained by a competitive adsorption model.
Bath B was more stable than bath A, and this characteristic was markedly enhanced by the addition of ferro of 300ppm. A smooth adhering film was obtained from bath B containing 20ppm bipy and 300ppm ferro at 60°C under a stirring condition at a rate of 15μm/h.