Patent ID: 8142916
Filing Date: 2012-03-27
Classification: G11B

Abstract:
1. A perpendicular magnetic recording medium with recording density higher than 150 Gbits per square inch, comprising: an orientation control layer, a non-magnetic under layer, a magnetic recording layer on a substrate, wherein the orientation control layer has an fcc structure and a (111) plane being parallel to the substrate; the under layer comprises two layers, said layers differing in crystalline characteristics, and has an hcp structure and a (0001) plane being parallel to the substrate; the magnetic recording layer has an hcp structure and a (0001) plane being parallel to the substrate; and a difference of the distance between nearest-neighbor atoms of the orientation control layer from the distance between nearest-neighbor atoms on a (0001) plane of the under layer is from −0.2 Å to +0.15 Å, wherein the orientation control layer is made of an alloy including Ni as a main component and 5 to 20 at % of one or more of Ti, V, Ta, Cr, Mo, and W as an addition element.