Modeling of Failure in Metallic Thin Films Induced by Stress and Electromigration: A Multiscale Computational Analysis

Abstract

AbstractA common failure mechanism in metallic thin-film interconnects is void propagation driven by electric fields and thermomechanical stresses. In this paper, a multiscale computational analysis is presented for predictive modeling of transgranular void dynamics. The modeling approach is hierarchical and involves atomistic simulations for property database development, molecular-dynamics simulations for understanding of void-tip mechanisms, and self-consistent mesoscopic simulations based on boundary-element methods and techniques for moving boundary propagation. An extremely rich void dynamical behavior is predicted, which includes faceting, facet selection, propagation of slits from the void surface, as well as formation of fine-scale crack-like features on the void surface, in agreement with recent experimental data.