Abstract-The impact of chloride ion concentration on electrochemical migration (ECM) of tin and silver was studied by using an in-situ optical and electrical inspection system. It was found, that in both cases, dendrites grow not only in an electrolyte solution at low chloride concentration but also in an electrolyte at medium and high or even saturated chloride concentrations as well. According to the results, the migration susceptibility has decreased at low and medium concentration levels in both cases. However, the ECM susceptibility of Ag has increased, while the migration susceptibility of Sn was decreased at the saturated concentrations.

Abstract:

The electrochemical migration (ECM) behavior of Electroless Nickel Immersion Gold (ENIG) surface finish was studied using Na 2 SO 4 solutions with various concentrations. The investigations were carried out by water drop (WD) test. During WD test the electrochemical processes were followed by electrical and visual inspections. Based on the meantime to failure (MTTF) data it was shown that MTTF increased at 0.1 mM Na 2 SO 4 solution, then on higher concentrations MTTF significantly decreased and stabilized over the concentrations.