Annealing effects on the properties of amorphous CoSiB/Pt multilayer films with perpendicular magnetic anisotropy

Abstract

The perpendicular magnetic anisotropy (PMA) of amorphous CoSiB/Pt multilayer systems was studied as a function of the thickness of the CoSiB/Pt bilayer and the number of repeated CoSiB/Pt bilayers. In this letter, we investigate the thermal property of a CoSiB single layer film annealed at 150 similar to 350 A degrees C for 3 hours and the perpendicular magnetic anisotropic property of amorphous ferromagnetic Ta(50 A degrees A)/Pt(30 A degrees A)/[CoSiB(2, 3, 4, 5, 6 )/Pt(14 )]5/Ta(50 ) multilayer films annealed at 200 similar to 400 A degrees C for 3 hours. The thermal properties were measured by using a differential scanning calorimeter and an X-ray diffractometer, and the magnetic properties were measured by using a vibrating sample magnetometer. The PMA of the CoSiB/Pt multilayer film disappeared and the multilayer film show isotropy after annealing at a temperature of 350 A degrees C or above.