Magnetic recording medium exhibiting low noise and high coercive force

Abstract

A magnetic recording medium exhibiting low noise and having a sufficiently high coercive force includes a magnetic layer having a granular structure including ferromagnetic crystal grains with a hexagonal closed packed structure and a nonmagnetic grain boundary region of mainly an oxide intervening between the crystal grains. An underlayer has a body-centered cubic lattice structure. A nonmagnetic intermediate layer with the hexagonal closest packed structure includes Ru, Os, and/or Re, which are provided between the magnetic layer and the underlayer. A degree of mismatching Δ=|d−d|/dis at most 10%, for instance, in a range from 2.5% to 7.0%, where dis a spacing of lattice planes of the crystal grains in the magnetic layer and dis a spacing of the lattice planes of the crystal grains in the intermediate layer. A proportion of the crystal grains with a grain size of equal or greater than 8 nm are at most 10% of the crystal grains included in the intermediate layer and a standard deviation of the grain size is at most 1.4 nm. The layers are deposited without preheating the substrate.