Magnetic recording medium having a Co-O magnetic layer, and specified in-plane properties
OwnerShogo Nasu, Koji Saikiinventors
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Abstract
A magnetic recording medium is disclosed, wherein a magnetic film comprising a partially oxidized cobalt with its in-plane coercive force not less than 500 Oe is provided on a substrate. Further disclosed are megnetic recording media, wherein there is further provided an underlayer comprising Cr, Fe or an Fe-Co alloy under said magnetic film, and wherein a perpendicular magnetic anisotropic film comprising a partially oxidized metal is further provided on said magnetic film. The magnetic recording media of the present invention are high in recording density and reproduction output, low in noise and high in S/N ratio.
Claims12
A magnetic recording medium, comprising a magnetic film consisting of Co-O having an in-plane coercive force not less than 500 Oe isotropically provided on a substrate, wherein said magnetic film has an in-plane squareness ratio of not less than 0.6 and wherein saturation magnetization is in a range of 300-700 emu/cm.sup.3.
A method for preparing a magnetic recording medium, wherein a magnetic film consisting of Co-O with its in-plane coercive force not less than 500 Oe isotropically and having an in-plane squareness ratio of not less than 0.6 and saturation magnetization in a range of 300-700 emu/cm.sup.3 is deposited by sputtering substantially perpendicularly under a pressure not more than 5 mTorr.
Dependencies are inferred from the claim text.