半导体引线脚纯锡电镀去氧化工艺对镀层变色的影响

Effect of Descale Process on Coating Discoloration in Pure Tin Lead-Electroplating

在欧盟的ROHS和WEEE指令的大背景下,引线脚的纯锡电镀大范围推广,但纯锡镀层变色问题却开始困扰大家。锡层表层被氧化、腐蚀是镀层变色的主要原因,其和镀层表面的粗糙程度、空隙率有较大关联,去氧化工艺的腐蚀性、氧化性、去除杂质金属粒子的能力都将影响镀层表面状态,进而影响镀层的抗变色能力。

In the background of the EU＇s ROHS and the WEEE directive, the feet of pure tin plating has applied extensively. But pure tin coating discoloration problem has plagued all the world. Layer surface oxidation and corrosion is the main reason for discoloration, and coating the surface roughness, porosity greater relevance, the corrosion of descale process, removing impurities metal particles will affect the crystal structure of coating surface, thereby affecting the anti-tarnishing coating capacity.