Theoretical Analysis of Vacancy Transport Combined with Electromigration and Stress Induced Voiding

Electromigration (EM) and stress-induced voiding have become significant in recent LSI interconnections due to the increase in current density and residual stress (Nemoto et al., 2006). Many works have been carried out to clarify the relationship between EM and residual stress (Gungor et al., 1998). The present authors have reported the numerical analysis of vacancy transport based upon the mass balance equation (Nemoto, 2006). This paper concludes that the behavior of vacancy transport by EM is influenced by residual stress. In this paper, an equation for vacancy transport is proposed to include the effect of residual stress. A computer-aided simulation and an in-situ observation test are conducted to discuss the quantitative relationship between current density and residual stress.