SUCCESSFUL FORMULATION of ENIG Plating

摘要

Many Pb-free alloy formulations, including SAC alloy (consisting of 3-4% silver, 0.5-1% copper and the balance tin), have been developed to replace leaded solder (typically, SnPb), and used successfully to manufacture and assemble printed circuit boards. As Pb-free solder can leave bumps on the traces during HASL (hot air solder leveling), many alternate surface finish processes have been investigated to overcome this challenge.