Patent ID: 7217467

Claim:
A perpendicular magnetic recording medium comprising a soft magnetic underlayer and a perpendicular recording layer which are deposited in this order over a substrate, said soft magnetic underlayer consisting of a first soft magnetic layer, a domain control layer consisting of an anti-ferromagnetic layer, and a second soft magnetic layer in This order from said substrate, wherein the energy of the exchange bias field Hex 2 which is applied to said second soft magnetic layer is larger than the energy of the exchange bias field Hex 1 which is applied to said first soft magnetic layer, and wherein, in a magnetization curve of said soft magnetic underlayer, measured when a magnetic field is applied in a radial direction of the substrate, a magnetization reversal slope occurs at a shift toward a positive direction of energy of the magnetic field and coercivity Hc of the soft magnetic underlayer, which is obtained from the magnetization curve, is smaller than the energy of the exchange bias field (which corresponds to the shift quantity) Hex.