KNaC_4H_4O_6和EDTA双络合体系碱性镀铜工艺研究

Study on the Alkaline Copper Plating from Double Complexant(KNaC_4H_4O_6 and EDTA) System

针对KNaC4H4O6和EDTA作为双络合剂的碱性镀铜工艺,通过测试分析阴极极化曲线、槽电压、光亮区电流密度、电流效率,考察了络合比、Cu2＋、KNaC4H4O6、导电盐KNO3、pH值对镀铜的影响。结果表明：Cu2＋质量浓度取7~12 g/L,络合比取2.5为宜;KNaC4H4O6可有效增大阴极极化,较大浓度时可大幅度提高光亮区的最大电流密度,但镀层结晶颗粒变大,有效的解决方法是加入适量的KNO3;pH值对阴极极化的影响不明显。采用该碱性镀铜工艺可获得光亮致密、孔隙率较低、与基体结合力良好的镀层。

By studying the cathodic polarization curves,cell voltage,bright current density,current efficiency,the influences of complex ratio,Cu2＋,KNaC4H4O6,and KNO3 from a double complexant（KNaC4H4O6 and EDTA） alkaline copper plating system were obtained.The results indicate that the optimum process is： Cu2＋ 7~12 g/L,complex ratio is 2.5.KNaC4H4O6 will enlarge the cathodic polarization,and increase the current density in bright current range when high concentration.It will however enlarge the crystalline particle,which can be eliminated by KNO3.pH is a non-significant factor to the cathodic polarization.Under such circumstances,the bright coating with excellent performances of combining power and lower porosity are obtained.