화학공학소재연구정보센터
Thin Solid Films, Vol.652, 28-33, 2018
Polycrystalline magnetite (Fe3O4) thin films from FeOx/Fe bilayers grown by pulsed laser depositions
The effect of heat treatment on the structural and magnetic properties of bilayered FeOx/Fe thin films grown by pulsed laser deposition on pre-oxidized amorphous SiO2/Si substrates has been studied. Post-deposition vacuum thermal annealing leads to remarkable changes in the structural and magnetic properties of the FeOx layer, which has been investigated by the combination of scanning electron and atomic force microscopy, Raman scattering spectroscopy and conversion electron Mossbauer spectroscopy. FeOx layer deposited at room temperature on top of the polycrystalline Fe underlayer is amorphous with the smooth surface (root mean square roughness similar to 0.5 nm). Vacuum thermal annealing of the FeOx/Fe stack at T= 500 degrees C leads to the formation of a polycrystalline Fe3O4/Fe thin film structure with the magnetite nucleation centers of an average size of 100 nm. The formation of the exact magnetite phase depends on the annealing conditions as shown by in-situ Raman and Mossbauer spectroscopy investigations.