Patent ID: 7566507
Filing Date: 2009-07-28
Classification: G11B

Abstract:
1. A perpendicular magnetic recording medium comprising: a substrate; an hcp Co-based magnetic layer; an hcp underlayer provided on the substrate with c-axes tilted at an angle between 10° to 45° from a substrate normal with a distribution at said angle being less than 5°, wherein said magnetic layer is grown epitaxially on said underlayer and in a vertical columnar fashion, and said magnetic layer includes at least a first magnetic layer provided on said underlayer and a second magnetic layer disposed above said first magnetic layer; an amorohous seed layer, having a thickness of at least 1 nm, disposed between said underlayer and said substrate; and a spacer layer made of a material selected from a group consisting of Ru, Re, Os, Ir, and alloys thereof and disposed between said first and second magnetic layers so that antiparallel coupling is induced between said first and second magnetic layers, wherein said amorohous seed layer includes one or a plurality of antiferromagnetic layers.