Magnetic properties of iron nitride thin films with high corrosion-resistance

Magnetic properties of FexN thin films prepared using ion-beam technique is reported. During the oblique incidence of iron, iron films were nitrized by nitrogen ions beam. A low energy broad-beam ion source (Kaufman type) was used for ionizing nitrogen. Magnetic properties of the films were studied static measurements and Mössbauer spectroscopy. It was found that the composition of the films consists mainly of α-Fe and ε-Fe2-3N whose composition ratio were depend on ion current during the evaporation. The film prepared at ion current of 0.47 A/m2had squareness ratio of 0.85 and the saturation magnetization of 4200 gauss. It is emphasized that those obtained thin films show remarkable corrosion-resistance. Little corrosion was observed after the film was placed in a 5 % saline solution for a month.