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

Cu/Ta/Si stacks were prepared and, subsequently, annealed at 650 °C with different electric field intensity (0–4.0 kV/cm). The effect of electric field intensity on atomic diffusion was determined from cross-sectional TEM micrographs of Cu/Ta/Si stacks. The atomic diffusion as well as the growth of amorphous layer at Ta/Si interface tended to enhance with the increased electric field intensity at 650 °C. The growth of amorphous layer obeyed a logarithmic law. The reduction in diffusion activation energy Q by increased electric field intensity will accelerate the atom diffusion, leading to significant barrier failure of Cu/Ta/Si stacks.