Tuning the electrical resistivity of pulsed laser deposited TiSiOx thin films from highly insulating to conductive behaviors

We report on the successful growth of amorphous TiSiOx thin films by means of pulsed-laser ablation of a TiO2/SiO2 composite target in a high-vacuum chamber. The room-temperature. resistivity, of the TiSiOx films is found to decrease by more than 6 orders of magnitude (i.e., from similar to2 x 10(4) to 10(-2) Omega cm) when their substrate deposition temperature (T-d) is increased from 20 to 600 degreesC. On the other hand, by subjecting these films to a post-deposition annealing at 600 degreesC in oxygen atmosphere, they become highly insulating with a resistivity level as high as 2 x 10(10) Omega cm, regardless of the T-d value. The presence of conductive titanium silicide and titanium sub-oxide local phases in the as-deposited TiSiOx films, as revealed by photoelectron spectroscopy analyses, appears to be the cause of the observed tremendous change in the film resistivity. In particular, it is shown that the resistivity of the TiSiOx films is strongly correlated with their. oxygen content. (C) 2004 American Institute of Physics.