Transgranular Crack Propagation in Thermal Cycling of SnAgCu Solder Joints

Lifetime predictions of lead-free solder joints remain a challenging task in assuring reliability of electronic packaging. Due to the complex interaction of a wide range of as-soldered microstructures, strong an isotropic properties and a failure mechanism that is not completely understood, life time predictions of SnAgCu solder joints remain a challenging task.In this work, we present experimental findings of transgranular crack propagation of SnAgCu solder joints in thermal cycling. These findings are in contrast with the established picture of a recrystallization-assisted intergranular crack propagation failure mechanism.