Growth of nanocrystalline $TiO_{2}$ films by MOCVD using a novel precursor

Thin films of $TiO_{2}$ have been deposited on glass substrates by metalorganic chemical vapour deposition (MOCVD) using a novel,volatile, stable, oxo-\beta-ketoesterate complex of titanium, viz.,bis(ethyl-3-oxo-butanoato)oxotitanium(IV) $[TiO(etob)_{2}]_{2}$. The complex was prepared through a straight forward synthesis. Various spectroscopic techniques have been used to confirm its structure.Thermogravimetric analysis has been carried out to study the thermal properties of the complex. Films of TiO, were grown from the complex by low-pressure MOCVD at temperatures ranging from 400 to 525 degrees C.These films were characterized for their morphology by transmission electron microscopy, scanning electron microscopy, and atomic force microscopy and by electron diffraction for their crystallinity. All the films grown in this temperature range are very smooth. Films grown above 480 degrees C consist of nearly monodisperse, nanocrystals of the anatase phase. Spectrophotometry shows the bandgap, to be in the range3.4-3.7 eV for films grown at different temperatures. It was observed that the bandgap increases with the decrease in the growth temperature,confirming the nanocrystalline nature of the $TiO_{2}$ films