Patent ID: 7867638

Claim:
A magnetic recording medium comprising: a nonmagnetic substrate; and at least three layers formed on the nonmagnetic substrate and comprised of a nonmagnetic orientation-controlling layer for controlling orientation of a layer formed directly thereon, a perpendicular magnetic layer having an easily magnetizing axis oriented mainly perpendicularly relative to the nonmagnetic substrate, and a protective layer; said perpendicular magnetic layer comprising two or more magnetic layers and at least one nonmagnetic layer, at least one of said magnetic layers being a lower layer having Co as a main component and containing Pt and an oxide and at least another of said magnetic layers being an upper layer having Co as a main component and containing Cr and no oxide; said lower magnetic layer being directly adjacent to and in contact with the orientation-controlling layer and comprising magnetic crystal grains isolated by an oxide penetrating said lower layer and dispersed in the lower layer, said crystal grains vertically penetrating said lower layer in columnar forms; said nonmagnetic layer being between said lower magnetic layer and said upper layer and having nonmagnetic grains that possess a columnar structure vertically penetrating said nonmagnetic layer; and said upper layer comprising magnetic crystal grains that are formed and epitaxially grown from surfaces of the magnetic crystal grains of the lower layer in a ratio of one to one.