Study of valence band structure of Fe doped anatase TiO2 thin films

We study the structural and electronic properties of Fe doped (4-8 at. %) and undoped TiO2 thin films deposited by pulsed laser deposition on Si(111) substrate. The films grow in single phase anatase structure of TiO2 as revealed by x-ray diffraction and Raman spectroscopy measurements. The Fe doped films reveal room temperature magnetic hysteresis behavior. We have probed the electronic environment of Fe in TiO2 matrix and its coupling to the cations, using photoelectron spectroscopy measurements. Photoelectron spectroscopic studies reveal the ionic state of Fe in TiO2, precluding the formation of Fe metal clusters. Valence band spectra of these films suggest that it primarily consists of O-2p derived state, however, Fe derived state is also observed in Fe doped films. Resonance photoelectron spectroscopy studies indicate that Fe ions are hybridized with Ti3+ defect states. (C) 2011 American Institute of Physics. [doi:10.1063/1.3624775]