Light-Induced CVD of Titanium Dioxide Thin Films I: Kinetics of Deposition

Titanium dioxide thin films are obtained by CVD on low temperature substrates (60–210 °C) using perpendicular irradiation from a long pulse 308 nm excimer laser. Titanium tetra-isopropoxide is used as the precursor in an oxygen-containing atmosphere with a total pressure in the chamber of 10 mbar. An empirical law describing the growth rate as a function of the experimental parameters (substrate temperature and laser fluence) is derived. The deposited thickness is proportional to the number of photons and has an Arrhenius dependence on the substrate temperature. Low growth rates per pulse (less than 0.1 nm per pulse) obtained allow a good control of the deposited thickness, while the use of high laser repetition rates leads to high temporal growth rates (up to 100 nm min–1).