A New Algorithm for EM Analysis Considering Multiple Driving Forces Mechanism

This paper studies the numerical simulation method for electromigration void incubation and afterwards void propagation based on commercial software ANSYS Multi-physics and FORTRAN code. The electronic migration formulation considering the effects of the electron wind force, stress gradients, temperature gradients, as well as the atomic concentration gradient has been developed for the electromigration failure mechanisms. Due to introducing the atomic concentration gradient driving force in atomic flux formulation, the conventional atomic flux divergence method cannot be used in the new EM algorithm. Therefore the corresponding EM atomic concentration redistribution method is proposed using FORTRAN code. A link between ANSYS and FORTRAN code is developed to transfer the data. The atomic concentration information is imported into ANSYS Multi-physics and then the atomic concentration distribution of the studied structure can be gotten. Finally, the comparison of voids generation through numerical example of a SWEAT structure with the measurement result is studied and discussed.