The influence of nanoscale morphology on the resistivity of cluster-assembled nanostructured metallic thin films

We have studied in situ the evolution of the electrical resistivity of Fe, Pd, Nb, Wand Mo cluster-assembled films during their growth by supersonic cluster beam deposition. We observed resistivity of cluster-assembled films several orders of magnitude larger than the bulk, as well as an increase in resistivity by increasing the film thickness in contrast to what was observed for atom-assembled metallic films. This suggests that the nanoscale morphological features typical of ballistic films growth, such as the minimal cluster-cluster interconnection and the evolution of surface roughness with thickness, are responsible for the observed behaviour.