Crystallites orientation of granular perpendicular magnetic recording media on FeCoB soft magnetic underlayer with high anisotropy field

Abstract

FeCoB films with a bcc(110) crystalline orientation were prepared as crystalline soft magnetic underlayers (SULs) for CoPtCr-SiO_2 perpendicular magnetic recording media. Ru layers and Si/NiFe layers as underlayers of FeCoB layers were introduced in order to enhance high in-plane anisotropy field and change a bcc-FeCo (110) orientation. The effect of FeCoB crystalline SULs on Ru intermediate layers was investigated. Ru/CoPtCr-SiO_2 films deposited on the bcc-FeCo (110) oriented FeCoB films exhibited (001) preferential orientations of the CoPtCr as well as the (001) orientation of Ru intermediate layer and possessed perpendicular magnetic anisotropy of the recording layer. It is indicated that the application of a crystalline SUL and the improvement of a bcc-FeCo (110) orientation in the SUL promote the reduction of the intermediate layer thickness.