Numerical and experimental analysis of Cu diffusion in plasma-treated tungsten barrier

Abstract

This work investigates Cu diffusion in sputtered and N2O plasma-treated W films. N2O plasma-treated W barrier has a nanostructured surface layer and shows high thermal stability and the best barrier properties. Also investigated herein are the lattice and grain boundary diffusivities extracted from the Cu penetration depth profiles using the Whipple analysis of grain boundary diffusion and Fick's second law of diffusion. Analysis indicates that the diffusion models correlate well with experimental results. (C) 2004 The Electrochemical Society.