Structure and magnetic properties of Fe–N films prepared by ion-beam-assisted deposition

Abstract

Fe–N films were prepared by ion-beam-assisted deposition at different N/Fe atomic arrival ratios to the substrates. Films consisted of nitrogen-rich α-Fe and different phases of iron nitrides including ζ-Fe2N, ε-Fe2-3N, and γ′-Fe4N were formed. The phase composition of Fe–N films was found to depend sensitively on the N/Fe atomic arrival ratio and deposition temperature. The magnetic properties of the films mainly depends on phase composition. It was found that nitrogen-rich α-Fe films exhibited higher Ms than that of the pure iron film, and their Ms could be increased further by vacuum annealing at relatively low temperatures.