Abstract
Highly ordered (001)-oriented FePt nanoparticles (NPs) with controllable sizes and well-aligned easy axis were obtained by tuning the total layer number n of atomic-scale [Fe/Pt/ SiO2] n multilayers deposited on SiO2 Si substrates. After annealing at 700 °C, the ordered FePt NPs with a small particle size of 5.5 nm (an extremely high areal density of 1.2× 1013 dots/in.2), a large out-of-plane coercivity of 28.5 kOe, and a narrow size distribution of 13% were attained. All NPs were embedded in the SiO2 substrates, resulting in a flat top surface. Finally, a full-stack film structure of perpendicular recording media composed of FePt NPs (recording layer), SiO2 (nonmagnetic intermediate layer) and CoZrTa (soft underlayer) was demonstrated. © 2009 American Institute of Physics.