Zainab T Hussain, Wasna’a M Abdulridha, Murooj A Abood, Farqad Saeed,
Volume 23, Issue 1 (MARCH 2026)
Abstract
In this study, RF magnetron sputtering was employed to create titanium dioxide (TiO2) thin films doped with zirconium oxide (ZrO2) (TZO) onto quartz and silicon substrates at 100oC for the purpose of evaluating the effect of ZrO2 doping on the microstructural, electrical, optical and gas sensing properties of the TiO2 films. Different doping concentrations (0.0, 2.0 and 4.0 wt.%) were used to compare performances of the films with a thickness ranging between 147 nm to 178 nm. Structural and surface morphology characterizations of the prepared films were carried out by X-ray diffraction (XRD) and atomic force microscopy (AFM) techniques. The surface morphology of the prepared TZO films showed a gradual reduction in the grain size while the doping concentration increased. The optical characteristics of the films also exhibited an increasing trend in the optical band gap with the rising ZrO2 concentration. TiO2 films showed an n-type conductivity as confirmed by Hall's measurement. The results of the gas sensing experiments revealed that the sensitivity of the TZO films for the detection of ethanol vapor increased with an increase in the concentration of ZrO2 dopant. Therefore, TZO film with 4.0 wt.% of ZrO2 could be used as an effective sensor for detecting ethanol vapor.
