PARAMETRIC INVESTIGATION FOR DIRECT CHEMICAL-VAPOR-DEPOSITION OF MAGNETITE FILMS

A direct growth of magnetite (Fe3O4) phase has been obtained by a low-pressure chemical vapour deposition (LPCVD) technique using metal-organic ferric dipivaloylmethanate (Fe(DPM)3) as precursor. On oxidation these films are converted to gamma-Fe2O3 phase which give superior magnetic coercivity values. Crystallographic structures are determined by small-angle XRD analysis. As-deposited magnetite and oxidized gamma-Fe2O3 films are reported with coercivity values of 93 and 122 kA/m, respectively. Squareness ratios of 0.80 are observed for both as-deposited Fe3O4 and oxidized gamma-Fe2O3 films with remanent magnetization values of 101 and 102 mT, respectively. Deposition conditions of the as-deposited films along with a growth mechanism involving a gas phase reaction, as promoted by a hot wall type reactor chamber, are described.