Controlling the magnetic anisotropy of CoPt/AlN multilayer films.

The magnetic anisotropy of sputter-deposited CoPt/AlN multilayer films has been studied in contrast with the multilayer films consisting of magnetic and noble metals. It has been found that the as-deposited multilayer film shows enhanced in-plane magnetic anisotropy compared with CoPt alloy film of equivalent thickness. However, upon thermal annealing in a vacuum, the film undergoes a smooth transition of magnetic anisotropy from in-plane to perpendicular direction; moreover, the anisotropy field and coercivity can be controlled by controlling the annealing temperature. Structural characterization has revealed that the perpendicular magnetic anisotropy of the annealed CoPt/AlN multilayer films is mainly of magnetoelastic origin. [ABSTRACT FROM AUTHOR]