乙醛酸化学镀铜工艺

Abstract

研究了以乙醛酸为还原剂的化学镀铜工艺、镀层结构和形貌。其镀液组成和操作条件为:28.0 g/l CuSO4.5H2O,44.0 g/l EdTA-2nA,10.0 Mg/lα,α'-联吡啶,10.0 Mg/l亚铁氰化钾,9.2 g/l乙醛酸,PH为11.5~12.5,θ为40~50℃。实验结果表明,化学镀铜溶液较稳定;镀液温度和硫酸铜质量浓度提高,铜沉积速率增大;较高的镀液温度下,化学镀铜反应的活化能较低,镀液稳定性下降;镀液PH在11.5~12.5可获得较好的铜镀层;随乙醛酸和络合剂质量浓度提高,铜沉积速率变化不大,但过量的乙醛酸导致镀液的稳定性降低;铜镀层为面心立方混晶结构,呈光亮的粉红色块状形貌,有较高的韧性。

An electroless copper plating process using glyoxylate as reductant was developed,structure and surface morphology of the deposit were also studied.The bath composition and operating conditions were:28.0 g/L CuSO4 · 5H2O,44.0 g/L EDTA · 2Na,10.0 mg/L α,α'-bipyridyl,10.0 mg/L potassium ferrocyanide,9.2 g/L glyoxylate,pH 11.5--12.5,temperature 40--50 ℃.Experimental results showed that:the electroless copper plating bath was quite stable;the copper deposition rate would increased in case of bath temperature and copper sulfate concentration increased;the bath stability would decreased due to lower activation energy of copper deposition in case of higher temperature;the qualified copper coating could be obtained only at a proper bath pH range of 11.5--12.5;the copper deposition rate would not be affected by concentrations of glyoxylate and complexing agent evidently,whereas excessive content of glyoxylate would cause the bath stability decreased;the copper coating had a FCC mixed crystal structure with blocky grains、pink/bright appearance and good ductility.