Studies of the coupling of final d*-states in mixed Hf and Ti oxides (HfO2)x(TiOx)1−x and other complex oxides
نویسندگان
چکیده
X-ray absorption spectroscopy and vacuum ultra-violet spectroscopic ellipsometry are used to study the electronic structure of complex oxides comprised of mixed TM/TM and TM/RE oxides. Experimental spectra for HfTiO4 and Gd(Dy)ScO3 indicate multiple d-state features in the O K1 edge. These are compared with the empirical models for atomic d-state mixing. It is concluded that a mean field, virtual alloy model does not apply, and that the effects associated with the differences in atomic coordination and deviations from ideal octahedral or cubic bonding play a determinant role in d-state atom mixing. The results are applied band edge engineering options for high-k dielectric applications. ©
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