Solder Joint Reliability under Electromigration and Thermal-Mechanical Load

The numerical simulation method for electromigration in solder joint under the combination of current density and thermal mechanical load is investigated. The three dimensional electromigration finite element sub-model technique is developed. Numerical experiment is carried out to obtain the electrical, thermal and stress fields with the migration failure under high current density loads. The direct coupled analysis and indirect coupled analysis that include electrical, thermal and stress fields are performed and discussed. The viscoplastic Anand constitutive material model with both lead and lead-free solder materials is considered in the paper. A global chip scale package with PCB is modeled using relative coarse elements. To reduce the computational costs and improve the calculation accuracy, a refine submodel with trace and solder bump is constructed. The submodel is studied in a direct and indirect coupled multiple fields. The comparison and discussion of void generation through numerical example in this paper and previous experimental work is given.