It was recalled that, when modelling electromigration failure, it was common to assume the existence of a critical stress at which interconnect failure occurred. It was shown here that the atomic flux divergence, as directly deduced from 1-dimensional stress-based modelling, was more suitable for characterizing void formation during electromigration. Numerical analysis was used to model the evolution of stresses, atomic fluxes and flux divergences in an Al line which contained a fast-diffusion segment. The maximum flux divergence, rather than the maximum tensile stress, was shown to predict void locations which were consistent with microscopic observations; made using nano-indented monocrystalline Al lines. This was because the flux divergence directly reflected the extent of matter depletion, and therefore the tendency to voiding.

On the Prediction of Electromigration Voiding using Stress-Based Modelling. Q.F.Duan, Y.L.Shen: Journal of Applied Physics, 2000, 87[8], 4039-41