Stress-migration related electromigration damage mechanism in passivated, narrow interconnects

Abstract

In passivated metal interconnects, grain boundary sliding during cooldown from high temperature process steps provides the driving force and sites for void nucleation. Furthermore, residual stresses are known to result in appreciable growth of voids during and after cooldown. The current driven coalescence of such voids is shown to constitute an important failure mechanism for the lines during electromigration testing.