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.