Investigation of the role of compositional effects on electromigration damage of metallic interconnects

Compositional effects are usually observed in the early stages of electromigration of interconnects made of Al alloys like Al–Cu and Al–Si. These effects are due to a variation of the fraction of the solute species (Cu or Si) dissolved into the Al matrix mainly due to heating effects. Here we investigate the role of compositional effects on electromigration phenomena by using a dynamical percolation model that we have recently developed. Our results well reproduce several phenomenological aspects typical of electromigration experiments. This agreement, together with the flexibility of our approach, suggests wide possibilities of further extending the model to study also the geometrical and structural effects.