Capped L10-ordered FePt granular media with reduced surface roughness

L10-ordered FePtAg-C granular media capped with an FePtAg-SiO2 layer were fabricated in order to obtain stable flyability performance on a spin-stand tester. The post-annealed FePtAg-SiO2 was more suitable for the cap layer than an FePt alloy without segregants, since it formed a continuous structure on the well-isolated FePtAg-C layer. By using the optimized post-annealed FePtAg-SiO2 capped medium, the surface roughness (Ra) was reduced to 0.45 nm, thereby enabling stable flying at a glide height of 6 nm.