The electronics industry is in the midst of a transformation to eliminate lead (Pb) from electronic devices. This transformation initially started as a result of impending regulatory legislation. In the last two years, market pressure has emerged as the main impetus for electronics manufacturers to develop lead free alternatives. The materials, components and processes that comprise electronic assemblies are all affected by the requirement to be lead-free. The leading lead-free solder candidates required higher assembly processing temperatures. Consequently, even non-metallic materials such as plastics and printed circuit boards (PCBs) have to be evaluated for their ability to withstand higher processing temperatures. This paper examines the aspects that must be considered in the development of lead-free electronic connectors and reports current findings. These aspects can be grouped into three categories: (1) lead-free plating (solderable portion of the contact), (2) compliant or press-fit applications (non-soldered interconnection) and (3) housing (molded plastic which retains the contacts). Plating factors discussed include lead-free plating processability, solderability, and reliability. The phenomenon of tin (Sn) whiskering is discussed extensively due to the ambiguity surrounding an industry accepted test method and performance criteria. Finally, an evaluation of commonly used resins and their ability to withstand higher processing temperatures is presented.
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