Author/Authors :
Shvets، نويسنده , , V.A. and Aliev، نويسنده , , V.Sh. and Gritsenko، نويسنده , , D.V. and Shaimeev، نويسنده , , S.S. and Fedosenko، نويسنده , , E.V. and Rykhlitski، نويسنده , , S.V. and Atuchin، نويسنده , , V.V. and Gritsenko، نويسنده , , V.A. and Tapilin، نويسنده , , V.M. and Wong، نويسنده , , H.، نويسنده ,
Abstract :
Amorphous Ta2O5 films were deposited by sputtering Ta onto silicon substrates with reactive ion beam. Electron energy loss spectroscopy measurements on the film found that the plasma oscillation energy is 23.1 eV. The refractive index and the extinction coefficient were measured with spectroscopic ellipsometry over the spectral range of 1.9–4.9 eV. The optical band gap is found to be 4.2 ± 0.05 eV. The valence band consists of three bands separated by ionic gaps. The values of electron effective masses were estimated with DFT quantum-chemical calculation. Experiments on injection of minority carriers from silicon into oxide were also conducted and we found that the electron component of conduction current governed by the electron current in the amorphous Ta2O5.
Keywords :
Ab initio , XPS , band structure , dielectric properties , relaxation , electric modulus , ellipsometry , Atomic force and scanning tunneling microscopy
