UV pulsed laser deposition of magnetite thin films

Magnetite thin films were grown by pulsed laser deposition in O2 reactive atmosphere from Fe3O4 targets. The ablated material was deposited onto Si(1 0 0) substrates at various temperatures up to 623 K. The temperature dependence of structure and stoichiometry was investigated by X-ray diffraction (XRD) and conversion electron Mössbauer spectroscopy (CEMS). The XRD results show that films grown between 483 and 623 K are obtained as pure phase magnetite with an estimated average crystallite size increasing from 14 to 35 nm, respectively. This is in agreement with the CEMS spectra analysis, indicating isomer shift and internal field values for both the Td and Oh sites close to those reported for the bulk material and a random orientation of the magnetic moments. The influence of the deposition temperature on the estimated Fe(9−x)/3O4 stoichiometry is related to an increase in the vacancy concentration from 483 to 623 K.