This work aims to understand the reliability of SnAgCu solder interconnects used in PBGA packages using microstructure evolution, laser moire interferometry and finite-element modeling. A particle coarsening based microstructure evolution of the solder joint material during thermal excursions was studied for extended periods of time lasting for several months. The microstructure evolution and particle coarsening was quantified, and acceleration factors were determined between benign field-use conditions and ATC conditions for PBGA packages with different form factors and for two different...