The effect of thickness and annealing condition on the microstructure and magnetic properties of Fe/Pt multilayer thin films

Abstract [Fe(0.5 nm)/Pt(0.5 nm)] 40 , [Fe(1 nm)/Pt(1.5 nm)] 20 and [Fe(3 nm)/Pt(3 nm)] 10 multilayer were prepared by DC magnetron sputtering. By conventional furnace annealing (CA) at 270–600 °C for various time, all of the films still remained the disordered structure with the soft magnetic phase. By rapid thermal annealing (RTA) at 500 °C for various time, we obtained the [Fe(1 nm)/Pt(1.5 nm)] 20 and [Fe(3 nm)/Pt(3 nm)] 10 films with L1 2 ordered FePt 3 phase which was almost ferromagnetic at room temperature. However, the [Fe(0.5 nm)/Pt(0.5 nm)] 40 films was still disordered state even under RTA. Compared with CA, RTA exposed an outstanding effect on accelerating the phase transition when the film thickness is over [Fe(0.5 nm)/Pt(0.5 nm)] 40 .