Tin whisker mitigation study on alloy 42 pure tin plating

Tin plating on components finishes may grow whisker under certain condition. A42 (FeNi42) leadframe is well known on tin whisker growth after thermal cycling which caused by the thermal mismatch of tin and FeNi42. In this paper we study on finding the tin whisker mitigation to control the tin whisker growth within the whisker length specification limit (<50 mum) by studied on various leadframe pretreatment(descale) concentration, various pure tin plating chemistry and study on whisker mitigation technique on annealing (150C,1 hr) and SMT reflow