Stress induced enhancement of magnetization reversal process of DyFeCo films for MRAM element with perpendicular magnetization

Thin films with perpendicular magnetic anisotropy have a potential to achieve high-density perpendicular magnetic random access memory (p-MRAM). Since they require relatively large current density to induce magnetomotive force for the magnetization reversal, conventional MRAM suffers from high power consumption during the write process. In order to lower the power consumption, a method using the stress induced magnetic anisotropy to cause magnetization reversal will be applicable to writing. In this study, DyFeCo films were evaluated as a magnetic layer in p-MRAM element because of their large magnetostriction constants and perpendicular magnetic anisotropy. The DyFeCo films were deposited on glass substrate at room temperature by sputtering. Magnetization reversal process at room temperature was observed by ferromagnetic Hall effect. Mechanical stress were induced in the films to evaluate the change of magnetic property caused by stress induced effect.