Temperature-dependent resistivity of alternative metal thin films.

The temperature coefficients of the resistivity (TCR) of Cu, Ru, Co, Ir, and W thin films have been investigated as a function of film thickness below 10 nm. Ru, Co, and Ir show bulk-like TCR values that are rather independent of the thickness, whereas the TCR of Cu increases strongly with the decreasing thickness. Thin W films show negative TCR values, which can be linked to high disorder. The results are qualitatively consistent with a temperature-dependent semiclassical thin-film resistivity model that takes into account phonon, surface, and grain boundary scattering. The results indicate that the thin-film resistivity of Ru, Co, and Ir is dominated by grain boundary scattering, whereas that of Cu is strongly influenced by surface scattering. [ABSTRACT FROM AUTHOR]