Super Roughening Process Improves Solder Mask Peeling of Immersion Tin

摘要

This paper introduces BTH-2085 Super Roughening Process which is a novel pretreatment process. Pretreated by this process, an alveolate copper surface can be achieved, which can remarkably enlarge the copper surface area. This process specially suits for solder mask (SM) pretreatment. If adopts the traditional pretreatment such as pumice scrubbing and persulphate micro-etch pretreatment, copper surface can’t be roughed enough that adhesive ability between copper and solder mask may be poor. Sold Mask will be attacked by high temperature and chemicals, so solder mask peeling becomes a common problem after Immersion Tin and Electroless Nickel Immersion Gold ( ENIG). Common improving methods such as adjusting process parameters and trying different SM can’t solve this problem completely. Super Roughening Process pretreatment can improve the copper-SM adhesion and decreased SM peeled off. Therefore, SM peeling can be prevented effectively.