三乙醇胺和EDTA·2Na盐双络合体系快速化学镀铜工艺研究

Study on Electroless Copper Plating Technology of High Plating Rate in Triethanolamine and EDTA·2Na Dual-chelating-agent System

系统研究了以三乙醇胺（TEA）为主络合剂、EDTA·2Na盐为辅络舍剂的二次镀铜体系。实验结果表明镀速随EDTA·2Na盐浓度增加而减慢，随TEA浓度、硫酸铜浓度、甲醛浓度、溶液pH值和镀液温度的增加而加快；添加剂亚铁氰化钾、a。a＇_联吡啶和2-MBT均能使镀速减慢且浓度较低时均能使镀层外观变好；PEG-1000对镀速影响较小，但能使镀层质量变好。其二次化学镀铜最佳条件是：CuSO4·5H2O为16g／L，EDTA·2Na盐为6g／L，TEA为21．5g／L，pH值为12．75，甲醛（37％～40%）为16ml／L，亚铁氰化钾为100mg／L，a，a＇-联吡啶为20mg／L，PEG-1000为1g／L，2-MBT为0．5mg／L及镀液温度为50℃。在最佳条件下镀速达到10．57μm／h，SEM分析镀层表面光滑、结晶均匀。

Secondary electroless copper plating system of triethanolamine （TEA） and EDTA · 2Na dual-chelating-agent is researched in the paper. The test results indicate that plating rate increases with the increase of concentration of TEA ,CuSO4 · 5 H2O, HCHO and pH and bath temperature,and decreases with the increase of concentration of EDTA · 2Na. The additives＇ influence of K4 EFe（CN）6]· 3H2O,2-MBT and a,a＇-dipyridyl on plating rate is great but surface quality of copper film improves when concentration of that is low. Although the influence of PEG-1000 on plating rate is little, the influence of that on deposits quality especially copper surface is great. The optimal conditions of this electroless copper plating process are that TEA is 21.5 g/L ,EDTA ·2Na is 6 g/L ,HCHO is 16 ml/L,CuSO4 · 5H2O is 16 g/L,K4 [Fe（CN）6]· 3H2O is 100 mg/L,a,a＇-dipyridyl is 20 mg/L ,PEG-1000 is 1 g/L, 2-MBT is 0. 5 mg/L,pH is 12. 75,and bath temperature is 50 ℃. Plating rate reaches 10. 57 μm/h plating for 30 min in the bath. The SEM test demonstrates that the surface of copper film is smooth and grain is fine.