Effect of Sb doping on the structural, microstructural, and magnetic properties of TiO₂ thin films for sensor applications using evaporation technique

Undoped and Sb-doped TiO₂ thin films were synthesized via thermal evaporation and deposited on glass substrates, with Sb concentrations of 2, 4, and 6 wt.% in the MECA2000 evaporator. The structural, microstructural and magnetic properties of films with varying antimony doping concentrations (0, 2, 4, and 6 wt.%) were analyzed using X-ray diffraction with the MAUD program based on the Rietveld method and vibrating sample magnetometry (VSM). X-ray diffraction (XRD) shows that the undoped product corresponds to the anatase phase of TiO₂ and remains free from contamination even after adding 2% by weight of the impurity Sb. However, at higher Sb concentrations of 4 and 6% by weight, a phase transition occurs from anatase to rutile. The vibrating sample magnetometer results indicate that the undoped TiO₂ thin film displays ferromagnetic behavior at room temperature, with a saturated magnetic moment (M_s) of 0.71 × 10^–3 emu. Antimony doping at 2, 4, and 6 wt% enhances M_s to 1.24 × 10^–3, 1.47 × 10^–3, and 1.68 × 10^–3 emu, respectively.