Electroless cobalt alloy perpendicular anisotropy films plated from a simplified malonate bath

The electroless-plated Co alloy films for perpendicular magnetic recording were prepared from a newly developed plating bath with simplified composition, and their magnetic and structural properties were investigated. The composition of the films changed with varying cobalt sulfate concentration in the plating bath. The films containing 10-30 at% of Co in deposits, which show high crystallinity and crystal orientation, have perpendicular magnetic anisotropy. Among them, the Co-24 at% film shows the largest perpendicular magnetic anisotropy. The film consists of hcp crystallites whose 002 axis orients perpendicular to the film plane, showing high crystallinity and the crystal orientation from the initial deposition stage with a thickness of 20 nm. It was confirmed that the films for the use of highly functional devices can be fabricated from the electroless-plating bath with simplified composition.