Influence of Indium Addition on Whisker Mitigation in Electroplated Tin Coatings on Copper Substrates

Among many factors that influence whisker nucleation and growth in electroplated tin, it is now well established that small additions of Pb leads to whisker mitigation. To date, a good non-toxic elemental alternative to Pb that would mitigate whiskers remains elusive. In this work, a 50–100 nm In electroplated layer was incorporated into a 1-μm-thick electroplated Sn on a pure Cu substrate. In order to permit diffusion of In into Sn, heat...