Structural and magnetic studies of nanocomposite FePt-MgO films for perpendicular magnetic recording applications

Composite FePt–MgO films composed of L10 FePt nanograins were fabricated on glass substrates by annealing multilayer films of [FePt/MgO]3. Films with 2 nm FePt layer thickness that have Mr/Ms∼1.0 show a significantly improved (001) texture of L10 FePt with a narrow c axis texture dispersion resulting from insertion of 2 nm MgO layers between the FePt layers. Annealing the [FePt 2 nm/MgO 2 nm]3 film creates grains as small as 8.0 nm that confer a relatively high magnetic anisotropy constant Ku=5×106 erg/cc and thus fosters a high coercivity of approximately 10.0 kOe.