Effect of third element for FePt ordered alloy thin films with perpendicular magnetic anisotropy fabricated from Fe/Pt/X trilayer

L10-FePt ordered alloy thin films with (001) preferential orientation were fabricated by annealing Fe/Pt/X (X: Cu and Au) trilayers to reduce Curie temperature and ordering temperature. FePtCu film exhibited Curie temperature of around 280 °C and steep change of perpendicular coercivity to a measurement temperature |dHc⊥/dT| at around 200 °C. In addition, process temperature decreased to 500 °C by adding Au atom to FePt film and perpendicular coercivity was as high as 5.8 kOe even though annealing temperature was as low as 500 °C.