Magnetic Force Microscopy Study of Alternate Sputtered (001) Oriented L1₀ Phase FePt Films

We present a magnetic force microscopy study of alternate sputtered (001) oriented L1₀ phase FePt films. It is found that the root-mean-square value of phase shift of magnetic force images, (ΔФ)_rms, can be used to characterize the perpendicular anisotropy for a series of specimens. Therefore, the considerable improvement of the perpendicular anisotropy after post-annealing can be characterized. In addition, the magnetic properties, magnetic and crystalline microstructures before and after post-annealing are compared for the typical Fe_5nmPt_5nm10 film with substrate temperature T_s=500°C, single layer thickness d=5nm and total layer thickness D=100nm to confirm the effect of post-annealing on improving the perpendicular anisotropy for Fe--Pt films.