Ab initio simulation of the electronic structure of delta-Ta2O5 with oxygen vacancy and comparison with experiment

作者:Ivanov M V*; Perevalov T V; Aliev V Sh; Gritsenko V A; Kaichev V V
来源:Journal of Experimental and Theoretical Physics, 2011, 112(6): 1035-1041.
DOI:10.1134/S1063776111050037

摘要

The electronic structure of a Ta2O5 insulator with oxygen vacancies is studied theoretically and experimentally. The ab initio calculations of delta-Ta2O5 are performed in terms of density functional theory using the generalized gradient (GGA) and GGA + U approximations. The electronic structure of Ta2O5 is experimentally studied by X-ray photoelectron spectroscopy (XPS). To study oxygen vacancies, an amorphous Ta2O5 film is irradiated by argon ions. The calculated XPS spectra of the valence band of delta-Ta2O5 agree satisfactorily with the corresponding experimental spectra of the amorphous films. The oxygen vacancy in delta-Ta2O5 is found to be a trap for holes and electrons. The minimum and maximum effective masses of electrons and holes in delta-Ta2O5 are calculated.

  • 出版日期2011-6