Ta Buffer Layer Effect on the Growth of Fe 3 O 4 Thin Films Prepared by RF-sputtering

multi-layers were prepared by using RF-sputtering and ultra-high vacuum molecular beam epitaxy (UHV-MBE) techniques. After post-annealing the multi-layers at for 1 hour under the high vacuum of , we observed ferromagnetic properties at room temperature as well as the Verwey transition which is the typical features of magnetite crystals formed. We have carried out a comparative study of the effect of Ta buffered layer on the crystallinity and magnetic properties of thin films prepared under different growth and annealing conditions.