Electromigration and diffusion in ni-fe thin films

Abstract

Electromigration, the transport of matter as a result of passing a direct current, is a direct manifestation of an appropriate diffusion process. The results of electromigration studies with thin film Ni-Fe conductors (containing 80 wt %Ni and 20 wt %Fe) in the temperature range 200-330°C are reported in this paper. The activation energy for the associated diffusion process was found to be about 0.7 eV, indicating the dominance of grain-boundary diffusion. The direction of migration was investigated with electron microprobe techniques, and was found to be from the cathode to the anode. This observation indicates that the electron-wind term is dominant over the electrostatic term in determining the effective charge of the moving atoms. It was also observed that the migration rates of the Ni atoms and the Fe atoms were significantly different. © 1974 IOP Publishing Ltd.