Electromigration induced strain field simulations for nanoelectronics lead-free solder joints

Electromigration is a major road block on the way to realization of nanoelectronics. Determination of plastic deformation under high current density is critical for prediction of electromigration failure. A new displacement–diffusion coupled model is proposed and implemented using finite element method. The model takes into account viscoplastic behavior of solder alloys, as a result, vacancy concentration evolution and electromigration process are accurately simulated. Finite element simulations were performed for lead-free solder joints under high current density and compared with experimental moiré interferometry measurements. The comparison validates the model.