High frequency characteristics of soft magnetic Fe-O alloy thin films fabricated by helicon plasma sputtering

The effect of oxygen-doping has been studied on the magnetic properties of Fe thin films produced at room temperature by a helicon-plasma-enhanced RF magnetron sputter-deposition. A reduction in magnetic coercivity due to grain refinement was achieved using very low dose of oxygen, which did not lead to the formation of crystalline Fe oxides with the low saturation magnetization. Moreover, it was demonstrated that oxygen-doping also enhances the in-plane uniaxial magnetic anisotropy of Fe films and thus can be applied beneficially to increase high-frequency permeability which is needed in microwave applications.