Effects of Structure of FexN Intermediate Layers on Magnetic Properties of Fe/FexN Multilayered Films

stract-Fe multilayered films with Fe
_x
N intermediate layers of various structures (Fe+Fe
₄
N, +Fe
₄
N, ϵ and Fe
₂
N) were prepared by reactive sputtering under various nitrogen partial pressure conditions. The effects of the Fe
_x
N intermediate layers on the coercivity (H
_c
), saturation magnetization (B
_g
), and, structure of the Fe/Fe
_x
N multilayered films were investigated. Fe/Fe
_x
N multilayered films with intermediate layers prepared under conditions in which a single-layer Fe
₂
N film is obtained have a low H
_c
of less than 1 Oe. We found that the columnar growth of the Fe layers is interrupted in these films, grain sizes were reduced to less than 100 Å, and the lattice spacing of the -Fe (110) planes was increased. The low H
_c
of Fe/Fe
_x
N multilayered films is attributed to these factors.