Composition influence on the microstructures and magnetic properties of FePt thin films

The Fe_xPt_100-x (10 nm) (x = 31-51) thin films are fabricated on Si (100) substrates by using magnetron sputtering. The highly ordered L1₀ FePt phase is obtained after post-annealing at 700 ℃ in Fe₄₇Pt₅₃ thin film. The sample shows good perpendicular anisotropy with a square loop and a linear loop in the out-of-plane and the in-plane direction, respectively. The variations of the magnetic domains are investigated in the films when the content value of Fe changes from 31% to 51%.