The paper deals with TiO₂-based thin films, doped with Cr and N, obtained

by magnetron co-sputtering from titanium dioxide ceramic and chromium

targets in Ar + N₂atmosphere. Co-doped samples of Ti(Cr)O₂:N are investigated

from the point of view of morphological, crystallographic, optical, and

electrical properties. Characterization techniques such as: X-ray diffraction,

XRD, scanning electron microscopy, SEM, atomic force microscopy, AFM,

Energy Dispersive X-ray spectroscopy, EDX, X-ray photoelectron spectroscopy,

XPS, optical spectrophotometry as well as impedance spectroscopy are applied.

XRD reveals TiO₂ and TiO₂:N thin films are well crystallized as opposed to

those of TiO₂:Cr and Ti(Cr)O₂:N. XPS spectra confirm that co-doping has

been successfully performed with the biggest contribution from the lower

binding energy component of N 1s peak at 396 eV. SEM analysis indicates

uniform and dense morphology without columnar growth. Comparison

between the band gaps indicates a significant shift of the absorption edge

towards visible range from 3.69 eV in the case of non-stoichiometric

Ti(Cr)O_2−x:N to 2.78 eV in the case of stoichiometric Ti(Cr)O₂:N which should

be attributed to the incorporation of both dopants at substitutional positions

in TiO₂ lattice. Electrical conductivity of stoichiometric Ti(Cr)O₂:N increases

in comparison to co-doped nonstoichiometric TiO_2−x thin film and reaches

almost the same value as that of TiO₂ stoichiometric film.