新型ENEPIG封装基板化学镀钯工艺优化

Process Optimization of Electroless Palladium Plating for New Type ENEPIG Package Substrate

化学镀钯是制作新型ENEPIG印制电路板最关键的工艺,从化学镀钯反应机理入手,分析了影响质量的工艺参数,运用实验设计中健壮设计的实验方法,对工艺参数进行了优化,找到了新型ENEPIG印制电路板中化学镀钯的最优工艺参数:2.2 g/L氯化钯,13.2 g/L次磷酸钠,165 m L/L氢氧化铵,33 g/L氯化铵,镀液θ为55℃,pH为9.6。验证试验表明,应用改善后的镀钯工艺,钯的沉积速率明显加快,集中度也得到显著提高。

Electroless palladium plating is the most key process in new type ENEPIG printed circuit board manufacturing. In this paper,process parameters which influencing the quality were analyzed from the reaction mechanism of electroless palladium plating,and these parameters were optimized by using robust design experimental method of DOE. The optimal process parameters were founded as follows： PdCl22. 2 g / L,NaH2PO2 concentration 13. 2 g / L,NH4OH 165 m L / L,bath temperature 55 ℃,bath pH 9. 6,NH4Cl 33 g / L. Validation tests showed that the palladium deposition rate was accelerated obviously and the concentration was increased significantly after the optimized palladium plating process had been applied.