Investigating whisker growth on annealed and recrystallized tin platings

The aim of this research is to examine the effect of annealing and recrystallization of electroplated tin layers on mitigating the growth of tin whiskers. Electroplated tin on copper substrate has been tested. Three different groups of samples have been investigated: a reference, an annealed and a recrystallized. Three types of aging were being used to accelerate the whisker appearance; two life-like circumstances with constant elevated temperature in ambient humidity and a temperature cycling (TC) test. The whisker growth was observed by using Scanning Electron Microscopy (SEM) and was evaluated by the average and maximum whisker length and the average whisker density. It is shown that at different aging circumstances the whisker appearance and growth is decreasing in aspect of the applied pre-treatments.