Synthesis and characterization of mist chemical vapor deposited aluminum titanium oxide films

Aluminum titanium oxide (Al1-xTixOy, an alloy of Al2O3 and TiO2), an attractive high-κ dielectric material, was synthesized by mist chemical vapor deposition, utilizing Al2O3 and TiO2 precursors. X-ray diffraction investigations revealed that the Al1-xTixOy (0 < x < 0.72) films deposited at 400 °C have an amorphous-phase structure. It was found that the bandgap of the Al1-xTixOy films decreases with increasing Ti composition. Moreover, the obtained refractive index, mass density and bandgap of Al2O3 and TiO2 films are all comparable to those reported for high-quality Al2O3 and TiO2 films deposited by atomic layer deposition.