Fig. 1. Schematic diagrams illustrating the fabrication of TiO2 films with tuneable phase structures using a direct current reactive magnetron sputtering technique followed by rapid thermal annealing (RTA) treatment. (a) Uniform TiO2 films including TiO2-A and TiO2-R were obtained by RTA treatment of the precursor films deposited at a fixed O2 partial pressure (≥0%). (b) The TiO2-AR film was obtained by RTA treatment of the gradual precursor film deposited by adjusting the O2 partial pressure gradually from 12% to 0%. (c) The TiO2-dAR film was obtained by RTA treatment of the bilayer precursor film with an internal layer deposited at a fixed 12% O2 partial pressure followed by deposition of an external titanium layer at 0% O2 partial pressure. (d) The UV-vis absorption spectra of the obtained TiO2-A, TiO2-R and TiO2-AR films.
