Formation of a bcc (001)-textured CoFe layer by the insertion of an FeZr layer in multilayer-based stacks with perpendicular magnetic anisotropy

The effects of inserting an amorphous FeZr layer between the [Pt/Co] multilayer and the CoFeB/MgO layer in stacks possessing perpendicular magnetic anisotropy are examined. A 1-nm-thick FeZr layer is effective in forming a bcc (001)-textured CoFe layer during annealing by suppression of crystallization at the interface with the multilayer, which is terminated in a close-packed plane. Because FeZr is magnetic, it has an advantage over Ta, an alternative material used for the same purpose. Efficient magnetic coupling between the multilayer and CoFeB/MgO occurs even for large FeZr layer thicknesses, so the magnetic properties of the stack are only weakly affected.