MULTISCALE MODELING OF DEGRADATION AND FAILURE OF INTERCONNECT LINES DRIVEN BY ELECTROMIGRATION AND STRESS GRADIENTS

This article introduces a multiscale modeling approach for simulating a key aspect affecting the reliability in narrow interconnect lines: migration, growth and coalescence of voids driven by electromigration and stress gradients. This approach is based on the Monte Carlo method with a Hamiltonian that contains both short-range and long-range interactions. The short-range interactions are resolved at atomic scale while the contributions of the long-range interaction are computed by solving a subsidiary continuum boundary value problem for the elastic and electric field. Thus, this approach combines both discrete and continuum techniques to provide a numerical tool to follow the complex evolving topologies that are derived from void migration, growth and coalescence. The predicted results are in good agreement with key experimental observations and other numerical and theoretical estimates.