Effects of different titanium sub-oxide on the properties of titanium dioxide thin films prepared by e-beam evaporation deposition with ion auxiliary

Abstract

TiO₂ thin films were prepared with Ti₂O₃, Ti₃O₅ and TiO₂ as raw materials, by electronbeam evaporation deposition, using O²⁻ ion beam (O₂ purity up to 99.99%) as auxiliary means. The crystal structures of the samples were inspected by the X-ray diffraction (XRD) method, and the evaporation character of various raw materials was analyzed. Transmittance spectra were measured through a U-3310 spectrophotometer (wavelength ranging from 200 nm to 900 nm). The refractive index n and the thickness of films were determined from transmission spectra. The experimental results show that the thin films taking Ti₂O₃ as their raw material have a strong absorption, when taking Ti₃O₅ and TiO₂ as raw materials, the thin films would have good optical properties. The experiments also show that, the crystal structure of all thin films is amorphous before post-annealing and the Ti₃O₅ is a congruent evaporation phase in the Ti−O system.

Keywords

titanium sub-oxide / thin film / E-beam evaporation / IAD

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