Résumé:
Thin films of metallic oxides and pair oxides based on doped TiO2 have been
characterized using various techniques to study their structural, microstructural, and optical
properties. The characterization methods used include X-ray diffraction (XRD), scanning
electron microscopy (SEM), ultraviolet-visible spectrophotometry (UV-Vis), M-line
spectroscopy (MLS), atomic force microscopy (AFM), Raman spectroscopy (Raman), and
Fourier transform infrared spectroscopy (FTIR).
The Zn doped TiO2 thin films were prepared via the Sol-Gel method and deposited on
glass substrates using the spin-coating process, followed by thermal treatment at 500°C for 90
minutes. XRD analysis of the undoped TiO2 films revealed the formation of the anatase phase
with the A (101) plane as the preferred orientation. Increasing zinc concentrations inhibited
crystal growth in the TiO2 films. SEM images of both undoped and Zn doped TiO2 films showed
that the addition of zinc significantly altered the microstructure of the TiO2 films. The films
exhibited an average transmittance of 70 to 90% in the wavelength range of 350 to 900 nm and
an band gap between 3.6 and 3.51 eV. M-lines spectroscopy demonstrated that the Zn: TiO2
planar waveguides support single confined guided modes for both TE and TM polarizations.
MLS measurements indicated that zinc doping increases the refractive index, thereby enhancing
their waveguiding properties. Additionally, birefringence decreases as the zinc concentration
increases up to 7 %wt.
Regarding, the thin films of metallic oxides and pair oxides based on TiO2 (ZnO, CuO,
ZnO/TiO2 and CuO/TiO2) prepared by the Sol-Gel method (spin-coating) at 500 °C on glass and
silicon substrates, their structural properties were studied and identified by Raman spectroscopy
analysis. The Rms roughness values of thin films of metallic oxides and pair oxides based on
TiO2 were high, indicating that their surface is rougher compared to that of TiO2 single films.
Optical observations reveal that the thin films of TiO2, ZnO, and ZnO/TiO2 exhibit high
transmittance, ranging from 60 to 80%. In contrast, the thin films of CuO and CuO/TiO2 show
low transmittance. Finally, the band gap of thin films of metallic oxides and pair oxides based on
TiO2 varies from 3.69 to 4.05 eV.
