Enhanced L10 Ordering and (001) Orientation in FePt: Ag Nanocomposite Films by Monatomic Layer Deposition

The magnetic and structural properties of atomic-scale [Fe/Pt]₁₈ and [Fe/Pt/Ag]₁₈ multilayer films annealed at 350 and 400°C have been investigated. The results indicate that, by introducing thin Ag addition layers, the ordering temperature of FePt with nominal 7.4-nm thickness (excluding Ag thickness) can be significantly reduced to 350°C, at which a relatively large coercivity is achieved. When annealing temperature increases to 400°C, the atomic-scale [Fe/Pt]₁₈ and [Fe/Pt/Ag]₁₈ multilayer films show (001) orientation. The reduced diffusion length of atoms in atomic-scale multilayer films and an enhanced atomic diffusion coefficient produced by Ag doping led to the low-temperature ordering and (001) orientation of L1₀ FePt phase.