Low-temperature fabrication of TiO2 film on flexible substrate by atmospheric roll-to-roll CVD

Titanium dioxide (TiO2) thin film was fabricated using titanium isopropoxide as a precursor through an atmospheric low-temperature roll-to-roll chemical vapor deposition method. TiO2 was deposited on the PET substrate in the temperature range of room temperature to 100A degrees C, and the working pressure was 740 Torr. The surface morphology of TiO2 thin film was analyzed by field emission scanning electron microscopy and a 2D surface profiler. The results revealed that the growth rate of TiO2 film was 31 nm/min at 100A degrees C, and it also showed that the surface is uniform and smooth. Moreover, the lowest root mean square roughness (R (q)) value of 1.87 nm was obtained for TiO2 film prepared at 100A degrees C. The composition of TiO2 film was confirmed by X-ray photoelectron spectroscopy (XPS) analysis. The film showed very good chemical and optical properties while increasing the substrate deposition temperature. The UV-Vis spectroscopy analysis revealed that TiO2 films exhibited excellent optical transmittance, more than 91% observed in the visible region.