Optical properties of reactively sputtered Ta₂O₅ films

The optical properties of reactively sputtered Ta₂O₅ thin films are investigated in the 0.25–2.5 μm wavelength range. The dispersion curves for the refraction and absorption indices are obtained from the reflectance and transmittance spectra. From the absorption data, one electronic transition at 4.07 eV and another about 4.5 eV are obtained. Finally, the optical transitions in Ta₂O₅ are discussed.