Electromigration

As the trend of device miniaturization demands smaller and smaller components, the cross-section of nanoscale interconnect keeps shrinking and the current density keeps increasing, so does the probability of circuit failure induced by electromigration. Because electromigration is the interaction between atomic diffusion and electron flow, this chapter considers both atomic flux and electron flux, as well as their coupling due to the cross-effect in irreversible processes. Current crowding occurs when the flow of electrons turns, which is common in a 3-dimensional structure. The electromigration occurs due to electron wind force; however, the force cannot explain void formation in the low current density region. Heat generation is mainly due to Joule heating, which is entropy production on the basis of irreversible processes. The chapter considers the effect of a uniform temperature increase due to Joule heating on electromigration.