Patent ID: 8883328
Filing Date: 2014-11-11
Classification: G11B

Abstract:
1. A perpendicular magnetic recording medium, comprising: a nonmagnetic substrate, a soft magnetic layer on the nonmagnetic substrate, a seed layer comprising one of Ni or Co and at least one element selected from the group consisting of Cr, Ta, Fe, Mo, Nb, Zr, Si and B, the seed layer having fcc crystal structure or hcp crystal structure, a corrosion prevention layer comprising the element Cr and at least one element selected from among Ni, W, Mo, Nb, Ta, and Ti, with a total atomic ratio of all components other than Cr equal to or less than 40 at %, the corrosion prevention layer having fcc crystal structure or hcp crystal structure, a nonmagnetic intermediate layer comprising an element selected from the group consisting of Ru, Re, Ti, Zr, Nd, Tm and Hf, disposed directly on the corrosion prevention layer, a magnetic layer disposed directly on the intermediate layer having an easy axis of magnetization oriented perpendicular to the substrate, and a protective layer on the magnetic layer, wherein the soft magnetic layer, the seed layer, the corrosion prevention layer, the intermediate layer and the magnetic layer are in this order.