Modulation of preferred orientation and easy axis of magnetic anisotropy in L10 FePt films with Cu buffer layers

The crystallographic orientation and easy axis of magnetic anisotropy in L10 FePt films were successfully modulated with Cu buffer layers. The FePt film directly grown on the Cr90Mo10 underlayer showed a (001) preferred orientation with out-of-plane magnetic anisotropy. As the Cu buffer layer thickness was ≥4 nm, the FePt films showed a (110) preferred orientation with in-plane magnetic anisotropy. The FePt films on the Cr90Mo10 underlayers showed a continuous microstructure, while they showed a particle-like structure when the Cu buffer layers were used. The grain size of the FePt films increased with increasing Cu buffer layer thickness. The cross-sectional image revealed that the FePt film with 12 nm Cu buffer layer had columnar structure. The experimental results suggested that the Cu films can be a promising buffer layer for controlling the texture and easy axis of the magnetic anisotropy of FePt films.