A method of manufacturing a magnetic recording medium comprises sequential steps of: (a) providing an apparatus for manufacturing the medium; (b) supplying the apparatus with a substrate for the medium; (c) forming a magnetic recording layer on the substrate in a first portion of the apparatus; (d) treating the magnetic recording layer with oxygen gas in a second portion of the apparatus at a sub-atmospheric pressure and for an interval sufficient to provide the resultant medium with at least one of the following, relative to a similar medium manufactured by a similar method but wherein the oxygen treatment of step (d) is not performed: (i) a more negative nucleation field (H.sub.n); (ii) increased remanent squareness (S.sub.r); (iii) increased signal-to-medium noise ratio (SMNR); (iv) narrower switching field distribution (SFD); and (v) decreased thermal decay rate; and (e) forming a protective overcoat layer on the oxygen-treated magnetic recording layer in a third portion of the apparatus.
CROSS-REFERENCE TO PROVISIONAL APPLICATION
This application claims priority from U.S. provisional patent application Ser. No. 60/475,834 filed Jun. 3, 2003, the entire disclosure of which is incorporated herein by reference.
A method of manufacturing magnetic recording media, comprising sequential steps of: (a) providing an apparatus for manufacturing the media; (b) supplying the apparatus with at least one substrate for the media; (c) forming a magnetic recording layer on the at least one substrate in a first portion of the apparatus, the magnetic recording layer including a surface; (d) treating the surface of the magnetic recording layer with an ionized oxygen-containing plasma in a second portion of the apparatus to form a plasma oxidized surface layer; and (e) forming a protective overcoat layer on the plasma oxidized surface layer of the magnetic recording layer in a third portion of the apparatus.
A granular perpendicular magnetic recording medium, comprising: (a) a non-magnetic substrate having a surface; and (b) a layer stack on the substrate surface, the layer stack including a granular perpendicular magnetic recording layer formed by: (1) reactively sputtering a target comprised of a magnetic alloy in an atmosphere containing at least one ionized oxygen species derived from a source gas comprised of a compound of oxygen and at least one other non-metallic element; and (2) oxidizing an exposed upper surface of the granular perpendicular magnetic recording layer by generating a plasma containing at least one ionized oxygen species derived from a source gas comprised of a compound of oxygen and at least one other non-metallic element and treating the exposed upper surface of the granular perpendicular magnetic recording layer with the plasma.
