Transient fracturing of solder joints subjected to displacement-controlled impact loads

The transition from lead-containing to lead-free solder alloys has brought serious reliability issues for solder interconnects under dynamic loading conditions, for which fracturing is constantly observed around the interface between the solder alloy and the bonding pad, where intermetallic compounds develop. To evaluate and compare solder joint strengths in an accelerated test environment having fracturing of intermetallic compounds as a dominant failure mode, in this paper, we present numerical studies of transient fracturing of a package-level solder joint subjected to displacement-controlled impact loads. The explicit three-dimensional finite element analysis is incorporated with contact, fracturing and fragmentation mechanisms to predict transient structural responses and failure modes of the solder joint. Different intermetallic compound strengths, different impact velocities, and different impact angles are prescribed and corresponding structural responses and failure modes are investigated.