Structural, morphological and optical properties of fluorine doped titanium dioxide nanostructure thin film

Thin films of Fluorine (F) doped Titanium dioxide ( F: TiO2) are deposited at (0, 2 and 4% ) Fluorine content by the spray pyrolysis technique (SPT). Structural properties were analyzed by XRD, the results revealed anatase phase for all samples with special orientation along (101) plane. The crystallite size was increased from 9. 75 for pure TiO2 to 10. 67 for (TiO2: 4% F) film, whereas the dislocation density (δ) parameter increased from 109. 18 to 88. 16, but the strain(%) parameter decreases from 36. 21 to 32. 53. Transmittance displays excellent transparent films, in the visible area 83% and 75 %, for TiO2 and 4% F content. The absorption coefficient increased with increasing of F content, AFM images shows that the Undoped TiO2 and TiO2:F films a smooth surface topography with a decrement in The average particle size is noticed to be 77. 16 nm to 55. 36 nm, and average roughness (Ra) of surface was about (5. 45 – 2. 53) nm, and root-mean square (rms) roughness values from 6. 60 nm to 4. 10 nm for the deposited films. However, the optical band gap was slightly decreased from 3. 50 eV to 3. 46 eV with the F content increases.