Quantitative studies of electric field intensity on atom diffusion of Cu/Ta/Si stacks during annealing

Abstract

It has been shown that enhanced electric field intensity (0–4.0 kV/cm) has an obvious effect on accelerating atom diffusion in Cu/Ta/Si interconnect stacks at 650 °C. The theoretical deduction proves that diffusion coefficient is accelerated proportional to an acceleration factor (1 + a·αE/0.8)2. The analysis indicates that the accelerating effect is mainly attributed to the perturbation of the electric state of the defects and enhanced vacancy and dislocation densities.