Dynamic fuse model for electromigration failure of polycrystalline metal films

We introduce a dynamic fuse model for the damage done to a current-carrying polycrystalline metal film by electromigration. For all initial densities of defects p, the mean failure time 〈Tf〉 is, to an excellent approximation, proportional to the average length of the shortest path across the film in a certain metric. 〈Tf〉 tends to zero as (pc-p)4/3 as the percolation threshold p=pc is approached.