Electronic structure and x-ray-absorption near-edge structure of amorphous Zr-oxide and Hf-oxide thin films: A first-principles study

Abstract

First-principles calculations were performed on the electronic structure and x-ray-absorption near-edge structure (XANES) of amorphous Zr-oxide and Hf-oxide thin films. Using the discrete variational X-α method, the authors simulated the films with (Zr4O17)−18 and (Hf4O18)−20 clusters. The O–Zr and O–Hf bonds were found to have different characteristics along the bond orientation. By comparing the experimental and calculated XANES, we analyze the absorption mechanism of amorphous Zr-oxide and Hf-oxide thin films for energies up to 10eV above the OK edge.

Bluish-White Emission from Radical Carbonyl Impurities in Amorphous Al2O3 Prepared via the Pechini-Type Sol−Gel Process

“…The electronic structure of amorphous alumina and defective amorphous alumina using CASTEP code based on the density functional theory (DFT), and exchange and correlation have been treated by the generalized gradient approximation (GGA) within the scheme due to Perdew−Burke−Ernzerhof (PBE). , This method has been applied to many materials, such as amorphous ice, amorphous silicon, amorphous indium phosphide, and so forth. − In this calculation, the structural model of defective amorphous alumina was established containing 161 atoms as a superlattice with constant volume and under periodic boundary conditions (Figure b). The calculated band structures of amorphous alumina and defective amorphous alumina are given in parts a and b, respectively, of Figure .…”

X-ray photoemission and X-ray absorption studies of Hf-silicate dielectric layers

“…Information on the valence band offsets are extracted from the synchrotron radiation photoemission spectra acquired at 30 eV photon energy. X-ray absorption measurements at the O 1s absorption edge are used to provide information on the conduction band electronic structure as the states which contribute to the conduction band minimum (CBM) are the O 2p * mixed with the Hf 5d * and the 6s * orbitals [9,10].…”

The electronic structures for the optical absorption of Hf-O-N thin films

“…The peak at −1.9 eV is related to the antibonding interaction between Hf 5d-Hf 5d and two peaks at −5.1 eV, −7.0 eV are related to the bonding interaction of Hf 5d -Hf 5d. The optical absorption was due to the electron transition from O 2p in the valence band and Hf 5d in the conduction band [15].…”