Patent ID: 7056606
Filing Date: 2006-06-06
Classification: G11B

Abstract:
1. A magnetic recording medium comprising: a non-magnetic substrate; at least a soft magnetic undercoat film comprising a soft magnetic material and formed on the non-magnetic substrate; an orientation control film formed on the soft magnetic undercoat film for controlling an orientation of a film directly above the orientation control film; a perpendicular magnetic film which is formed on the orientation control film and has an axis of easy magnetization oriented mainly perpendicularly with respect to the substrate; and a protection film formed on the perpendicular magnetic film, wherein the perpendicular magnetic film has a structure in which magnetic grains are separated by a grain boundary layer, and an average separating distance between the magnetic grains along a straight line which connects centers of gravity of mutually neighboring magnetic grains is 1 nm or greater, and wherein the perpendicular magnetic film comprises a CoPtX alloy (X being at least one of SiO