Substrate effect on texture properties of nanocrystalline TiO2 thin films

Titanium oxide (TiO2) nanocrystalline thin films have been grown on different substrates LaAlO3 (0 0 1) and α-Al2O3 (0 0 0 1) by dc magnetron sputtering in an Ar+O2 gas mixture. Pure rutile or anatase or mixed (rutile and anatase) phase of TiO2 can be grown at fixed sputtering pressure and substrate temperature on various substrates. XRD and TEM studies of the films deposited at fixed pressure of 2×10−2 Torr and substrate temperature of 650 °C revealed that preferred (0 0 4) oriented anatase phase was observed in case of films grown over LaAlO3 substrates and rutile phase with preferred (2 0 0) orientation was observed in case of films deposited over the sapphire substrate. The results indicate that the film growth direction is highly affected with nature of substrate and substrate orientation. Further, AFM and FESEM images showed that nanostructured TiO2 films could be grown on all substrates.