摘要 |
A bit-patterned media (BPM) magnetic recording disk has a cobalt (Co) alloy recording layer (RL), a ruthenium (Ru) containing underlayer (UL), and a noble metal film (NMF) as an interlayer between the RL and the UL. The RL is preferably oxide-free and is a Co alloy, like a CoPtCr alloy, with a hexagonal-close-packed (hcp) crystalline structure with its c-axis oriented substantially perpendicular to the plane of the RL. The NMF is an element from the Pt group (Pt, Pd, Rh, Ir) and Au, or an alloy of two or more of these elements, and has a thickness less than 3.0 nm, preferably between 0.3 and 1.0 nm. The NMF does not interrupt the epitaxial growth of the RL and has little to no effect on the distribution of the RL c-axis orientation. The NMF increases the coercivity (Hc) and perpendicular magnetic anisotropy constant (Ku) of the RL. |