It was noted that experimental data on the migration of Cu impurities in TiN and in
similar diffusion barriers had led to conflicting suggestions concerning the
underlying physical mechanisms. Here the results of first-principles calculations,
which were in agreement with measured activations energies, were used to
elucidate the atomic-scale processes of moderate and rapid diffusion of Cu through
the bulk and intergrain voids of TiN films, respectively. It was also found that O
and H impurities were fast diffusers in TiN. The results offered an assessment of
the efficiency of TiN diffusion-barriers with respect to properties such as the nature
of the impurity, stoichiometry and crystallinity.
Migration of Species in a Prototype Diffusion Barrier: Cu, O, and H in TiN.
L.Tsetseris, S.Logothetidis, S.T.Pantelides: Applied Physics Letters, 2009, 94[16],
161903