Influence of microstructure on electromigration dynamics in submicron Al interconnects: Real-time imaging

Systematic studies of the influence of local microstructure on electromigration (EM) dynamics in submicron Al (0.5 wt % Cu) interconnects were performed using in situ transmission electron microscopy. This approach has allowed us to observe, in real time, voids forming, growing, migrating, pinning, failing a runner; and healing all with respect to the detailed local microstructure of the runners, In this letter, we report and describe how grain boundaries dramatically influence almost all aspects of EM-induced void and failure dynamics in submicron runners. In addition, we report that EM voids nucleate at grain boundaries long before open-circuit failures occur. These findings have important implications for electromigration modeling. (C) 1996 American Institute of Physics.