Patent ID: 7862916
Filing Date: 2011-01-04
Classification: G11B,Y10T

Abstract:
1. A perpendicular magnetic recording medium comprising: a non-magnetic underlayer composed of Ru or an Ru alloy having a columnar structure in which crystalline particles are isolated from each other by a space; a non-magnetic granular layer provided on said non-magnetic underlayer and composed of crystalline particles and a non-soluble phase; and a granular magnetic layer provided on said non-magnetic granular layer and composed of CoCrPt alloy crystalline particles and the non-soluble phase, wherein when a lattice constant in an in-plane direction of said non-magnetic underlayer is al, the lattice constant in the in-plane direction of said non-magnetic granular layer is a wherein the non-magnetic granular layer is formed of an Ru—Co alloy and an oxide or an Ru—Co alloy and a nitride.