Finite Element Analysis of Electromigration and Stress Induced Diffusion in Deformable Solids

Abstract

AbstractWith a view to analyzing failure mechanisms in interconnects, we have developed a finite element method that may be used to compute the effects of diffusion and deformation in an electrically conducting, deformable solid. The analysis accounts for large changes in the shape of the solid due to surface diffusion, grain boundary diffusion, and elastic or inelastic deformation within the grains. To illustrate the capabilities of the method, we have analyzed void migration and collapse due to current induced surface diffusion; the drift of a strip of conducting solid on a substrate; and have calculated intergranular stresses and plastic deformation induced by electromigration in a passivated, polycrystalline interconnect line.