Effect of Annealing on Perpendicular Magnetic Anisotropy and Low Saturation Magnetization of MgO/Co2FeAl/Mo Trilayer Films

摘要

In this study, we report our approach to manipulate the strength of perpendicular magnetic anisotropy (PMA) at oxide/ferromagnetic metal of Heusler alloy (HA) interface by tuning the parameter of annealing temperature. Robust PMA energy density (K-eff) of similar to 0.43 x 10(6) erg/cm(3) and small saturation magnetization (M-s) as low as similar to 248 emu/cm(3) have been achieved for MgO/Co2FeAl (CFA)/Mo stacks at 400 degrees C. We identify that PMA energy is thermally stable up to the maximum temperature of 400 degrees C. Effect of annealing temperature on surface morphology, grain distribution, and surface roughness of the stacks are investigated by atomic force microscopy (AFM). Further, X-ray photoelectron spectroscopy (XPS) study demonstrates that the interfacial oxidation decides the strong PMA property at MgO/Co2FeAl interface during the annealing process. This MgO/CFA/Mo trilayer system can be a suitable candidate for the development of low-power consumption, huge-density data storage, high-thermal stability against the annealing temperature, and nonvolatile magnetic memories.