Enhancement of structural and magnetic properties in sputtered half-metallic Fe3O4 films

Polycrystalline Fe3O4 films grown on different thicknesses of Fe underlayers were prepared by dc reactive-magnetron sputtering in an Ar+O-2 gas mixture and annealing under an infrared-lamp furnace system. Analyses of structural and magnetic properties revealed that a 15 nm Fe underlayer can be oxidized to Fe3O4 by increasing the oxygen flow crates during initial Fe3O4 layer growth. These analyses also confirmed the stoichiometry and high-crystallographic quality of grown Fe3O4. Adopting this method, Fe3O4 films can be grown without any other elemental buffer layers. (c) 2007 American Vacuum Society.