Gas-phase FT-IR analysis and growth kinetics of TiO2 in a hot wall LP-MOCVD reactor

Gas-phase FT-IR spectroscopy has been employed to study the thermal decomposition of titanium tetraisopropoxide in a hot-wall LP-MOCVD (low-pressure metal organic chemical vapor deposition) reactor under typical TiO2 deposition conditions. On the basis of such preliminary data, growths of TiO2 have been carried out in a spread range of experimental conditions: reactor temperature 390-420°C, total pressure 80-250 Pa, source temperature 30-60°C. Good-quality TiO2 thin films have been obtained both with and without the prsence of oxygen. A simple theoretical model which considers the occurrence of a parasitic reaction in the gas phase was developed to analyse and rationalise the experimental data.