Magnetic properties of Fe-N/Al-N multilayered films prepared by Ar ion-assist sputtering

Abstract

Fe-N/Al-N multilayered films were prepared by Ar-ion assist sputtering. The contents of nitrogen incorporated into the films were controlled by changing the nitrogen partial pressure in the mixture of Ar and N2 introduced into the sputtering ion source. The effects of Ar-ion bombardment onto growing film surfaces and post-annealing on their crystal structure and magnetic properties were investigated. The films with Fe and Al layer thicknesses of 50 and 10 Å deposited at ion bombarding voltage of 250 V and post-annealed at 150 °C possessed the saturation magnetization 4πMs of 16.2 kG and the relative permeability of about 4300. From those results, dual ion beam sputtering with Ar-ion bombardment is useful for controlling the crystallinity and magnetic anisotropy to prepare the soft magnetic Fe-N/Al-N multilayered films with large saturation magnetization.