Formation and structural features of nitrogen-doped titanium dioxide thin films grown by reactive magnetron sputtering

The structural features of N-doped titanium dioxide (N-TiO2) thin films deposited via reactive magnetron sputtering system with different nitrogen to oxygen ratio are analyzed. Bias voltage was used as a significant parameter involved in the deposition process. Grown films have two-phase structure consisting of anatase and ruffle mixture. The analysis of structure and morphology of the films by SEM, TEM, XRD, FTIR and XPS techniques showed the changing of anatase to ruffle ratio and grain size reduction in N-TiO2 thin films with increase of nitrogen content in the working gas at simultaneous bias applying. Nitrogen atoms in oxide form are located at the crystallites boundaries and this 2D quasi-layer of NOx species limits the epitaxial growth of TiO2 crystallites during film formation.