Growth and properties of titania and aluminum titanate thin films obtained by r.f. magnetron sputtering

摘要

Amorphous titania (TiO_2) thin films were prepared on glass and silicon substrates by radio-frequency (r.f.) magnetron sputtering. These films were studied by choosing different substrate temperatures, r.f. powers, and annealing temperatures. High dielectric constants of 100-500 and varied dielectric losses were obtained. The dielectric properties of annealed titania films depended on the deposition conditions. As-deposited and annealed titania films with high dielectric constants and low losses were obtained for films deposited at 200℃ and 100 W and at 300 ℃ and 150 W. Mechanical properties, such as internal stress and adhesion, of the titania films were evaluated. Optical properties, such as refractive index and optical transmittance, were also measured. To make a comparative study, aluminum titanate (Al_2O_3-TiO_2) films prepared from a target with an Al_2O/TiO_2 molar ratio of one were also studied.