Perpendicular magnetic recording medium and method of manufacturing the same and product thereof

Abstract

A perpendicular magnetic recording medium has a nonmagnetic substrate, a nonmagnetic underlayer, a magnetic layer, a protective film, and a liquid lubrication layer sequentially laminated on the substrate. The nonmagnetic layer is composed of a metal or alloy having a hcp crystal structure. The magnetic recording layer consists of ferromagnetic crystal grains and a nonmagnetic grain boundary phase mainly composed of an oxide surrounding the grains. A seed layer of a metal or alloy having a fcc crystal structure can be provided under the nonmagnetic underlayer, and a nonmagnetic alignment control layer can be provided under the seed layer. The recording medium can provide high output and low noise by improving the alignment of the magnetic recording layer, reducing the initial growth layer in the magnetic recording layer, and minimizing the grain size of the magnetic recording layer.

Dependencies are inferred from the claim text.