Effect of Substrate Temperature on Microstructure and Magnetic Properties of Single-Layered FePt Films

The single-layered Fe_5.4Pt_4.6 films with thickness of 30 nm are deposited directly on Si substrate at substrate temperatures (Ts) of 370 to 620°C. The single-layered FePt films incline to random orientation as the Ts is lower than 570°C. Upon increasing the substrate temperature to above 600°C, the peak intensity of (001)_FePt is much higher than that of (111)_FePt and the perpendicular squareness (S_⊥) is also much larger than that of in-plane squareness (S_//), indicating that the magnetic anisotropy of FePt film is changed from in-plane to out-of-plane. This finding reveals that a high perpendicular magnetic anisotropy of the FePt film can be obtained as the film is deposited at a higher substrate temperature of 620°C. Its perpendicular coercivity (Hc_⊥), perpendicular squareness and magnetization at 20 kOe are as high as 14.0 kOe, 0.96 and 473 emu/cm³, respectively.