Environmental Influence on Sn Whisker Growth

This paper considers the influence of 1) humidity and 2) acidic humidity on the growth of Sn whiskers. Sn whisker morphology was observed over a six-month period. The results show that the electroplated surfaces exposed to pure humidity are populated with Sn whiskers dimensionally smaller than surfaces exposed to acidic humidity. Variables analyzed include surface condition, Cu-Sn inter-metallic formation at the film/substrate interface by X-ray Diffraction (XRD), and film thickness.