Physics of Electromigration

This survey paper on electromigration describes factors which govern the rate of electromigration and therefore relate to the lifetime of conductors stressed at high current density. These include the type of metal conductor, the conductor cross sectional area, lattice, grain boundary and surface diffusion effects, the addition of alloying elements, temperature and current density as well as the thermal conductivity of the substrate. The effect of gradients in temperature, current density, conductor composition and grain size on conductor lifetime are also discussed.