To successfully navigate the transition from an entrenched Pb-based electronics manufacturing model to a fully integrated Pb-free manufacturing operation will require significant and coordinated modifications to many elements of currently operating electronics manufacturing organizations. Starting with the fact that no "drop-in" replacement for eutectic tin (Sn) - lead (Pb) solder exists, the demands of Pb-free production will alter most facets of the manufacturing organization, from higher temperature processing with more expensive Pb-free alloys, to specifying component and laminate requirements able to tolerate the new constraints, to formulating new approaches for testing, inspection and quality control, to understanding the unknown reliability of Pb-free products. The elimination of Pb from electronic products will impact companies across the entire organization, not just at the manufacturing level. This will include product designers, component engineers, purchasing and quality assurance departments, sales and marketing groups, material vendors, assembly equipment suppliers original equipment and contract manufacturers, and recyclers. Clearly there is no shortage of work that needs to be done to place our understanding of Pb-free electronics production on the same level as the Pb-based counterpart. This paper discusses the comprehensive experimental approach that Cookson Electronics Division has taken to address the conversion to an integrated Pb-free manufacturing operation. The initial focus has been on materials compatibility for Pb-free processing using statistically based experimental designs. The study investigates compatibility between several Pb-free alloys, board and lead finishes, and flux types for both wave and paste/reflow soldering, including extensive reliability testing of the Pb-free assemblies. The statistical methodology and the results from the study will provide guidance for the implementation of successful and reliable Pb-free processing and serves as a model for how to establish a dedicated Pb-free electronics manufacturing operation.
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