An Evaluative Study of Lead-free Deposits in High Speed Applications

摘要

Due to impending environmental legislation and regulation in Japan and Europe, and marketing & economic pressures, the connector manufacturers are facing challenges to meet the demand for lead-free components. Several chemical suppliers have come up with lead-free alternatives offering different baths with bright and matte deposits containing tin, tin-copper, and tin-bismuth. This study was initiated in the hopes of applying high speed plating to terminals utilizing their proprietary recipes and evaluating critically the bath performance, deposit properties and potential applications in electronic connectors. Data on bath operation, current efficiency, adhesion, solderability utilizing wetting balance, aging studies, morphology of deposits, porosity, composition and whisker growth are compared. Corrosion behavior of selected coatings was also studied. The general limitations and challenges from an operational viewpoint will be discussed.