Interface diffusion during electromigration in Al lines

Significant diffusion has been observed at the interface between Al and Al-oxide, during electromigration under conditions where grain boundary diffusion is traditionally thought to dominate. Voids form by localized Al thinning. These voids closely resemble those previously attributed to grain boundary diffusion. This has been studied by SEM, electron back-scattered (Kikuchi) diffraction and atomic force microscopy.<<ETX>>