The effect of heat treatment on the structural and magnetic properties of bilayered FeO x/Fe thin films grown by pulsed laser deposition on pre-oxidized amorphous SiO 2/Si substrates has been studied. Post-deposition vacuum thermal annealing leads to remarkable changes in the structural and magnetic properties of the FeO x layer, which has been investigated by the combination of scanning electron and atomic force microscopy, Raman scattering spectroscopy and conversion electron Mössbauer spectroscopy. FeO x …