Revisit to the finite element modeling of electromigration for narrow interconnects

Electromigration (EM) is an important reliability concern in ultralarge-scale integration interconnects. A refined EM model based on a driving force approach is proposed in this work. The distribution of atomic flux divergence is computed by an finite element method to predict the void nucleation site in interconnects. It is demonstrated that the proposed model is more accurate than the conventional counterpart for narrow interconnects. The validity of the proposed model is verified through the study of the reservoir effect in EM. The predicted critical reservoir length agrees well with the reported values.