无铅化PCB表面材料及工艺特点

Material and Technology Characters of Lead-free PCB Finish

无铅化电子组装中PCB表面镀层技术主要有无铅钎料热风整平、浸锡、浸银、化学镀镍/浸金和有机可焊保护层五种。每种工艺技术具有各自的优缺点,每种工艺材料与不同无铅钎料具有不同的兼容性。从可制造性、可生产性以及与无铅钎料的匹配性等方面对五种PCB表面镀层技术做了较为全面的阐述,并通过对润湿性和可靠性评估得到一定的最佳配比,为无铅化生产提供了一定的指导作用。

HASL,I-Sn,I-Ag,ENIG and OSP are main PCB finish materials and coating technology in lead-free electronic assembly,which have advantages and disadvantages either,and have different compatibility with lead-free solder as well.Illustrate the five kind of coating process in detail form manufacturability,producibility and combinability with lead-free solder,and get a series of optimum combination by estimating wettability and reliability,which provide a guidance for production.