Electromigration-induced failure of metallic thin films due to transgranular void propagation

Abstract

A theoretical analysis is presented of the failure of metallic thin films due to electromigration-induced morphological evolution of transgranular voids. Self-consistent dynamical simulations emphasize the important roles of the anisotropy of void surface diffusivity, the strength of the applied electric field, and the void size. Our simulations predict formation of stable faceted voids, formation of wedge-shaped voids through a facet selection mechanism, as well as failure due to propagation of slitlike features from void surfaces, in excellent agreement with recent experimental observations.