印制板的表面终饰工艺系列讲座 第二讲 超薄型超高密度挠性印制板的置换镀锡工艺

Lecture series on final surface finishing process for PCB -Ⅱ Process of replacement Sn plating for super thin flexible PCB with super density

新型NCI 8888置换镀锡工艺获得的锡镀层致密、无铅、无锡须,能承受长时间高温烘烤和多次回流,可用于超高密度超薄型挠性印制板。介绍了该工艺的特点、工艺流程及规范,以及镀液的维护、镀液成分的分析。测定了不同置换锡镀层在不同条件下的焊接性能。结果表明,置换锡镀层焊接性能都较好。

A new process (NCI-8888) of replacement Sn plating can be applied for super thin flexible PCB with super density. Sn plating obtained by the process was lead-free, dense, non-whisker, and could stand long time bake at high temperature and reflow for many times. Features, flow and specifications of the process, control of plating bath and analysis of components in solution were introduced. Solderabilities of three kinds of replacement Sn platings under different conditions were tested. Results show that all the platings have good Solderabilities.