Abstract: A perpendicular magnetic recording medium comprises a non-magnetic substrate having a planar surface and a stack of thin film layers overlying the substrate surface and including at least one perpendicular magnetic recording layer with a magnetic easy axis perpendicular to the plane of the layer stack, wherein a magnetically soft underlayer (“SUL”) is not present in the layer stack. The layer stack includes a first, amorphous and smooth-surfaced underlayer proximal the substrate surface, a second underlayer having a first crystallographic orientation overlying the first underlayer, a third underlayer having a second crystallographic orientation overlying the second underlayer, and at least one perpendicular magnetic recording layer having a crystallographic orientation similar to the second crystallographic orientation overlying the third underlayer.

Abstract: A granular magnetic recording medium comprises a non-magnetic substrate having a surface, a layer stack on the substrate surface, including an outermost granular magnetic recording layer, a cap layer on the granular magnetic recording layer, having a sputter-etched outer surface, and a protective overcoat layer on the sputter-etched outer surface of the cap layer.

Abstract: A magnetic recording medium having a substrate, a first magnetic layer and a second magnetic layer, in this order, wherein an exchange coupling in the first magnetic layer is lower than an exchange coupling in the second magnetic layer, and the first and second magnetic layers are in a film stack so that magnetic grains in the first magnetic layer are exchange coupled by a pathway through the second magnetic layer is disclosed. A method of manufacturing a magnetic recording medium by obtaining a substrate, depositing a first magnetic layer at a first sputter gas pressure and depositing a second magnetic layer at a second sputter gas pressure, in this order, wherein the first sputter gas pressure is higher than the second sputter gas pressure, and an exchange coupling in the first magnetic layer is lower than an exchange coupling in the second magnetic layer is also disclosed.

Abstract: A recording medium having a substrate, a first soft magnetic underlayer, a second soft magnetic underlayer and a perpendicular magnetic recording layer without a spacer layer between the first and second soft magnetic underlayers is disclosed.

Abstract: A perpendicular magnetic recording medium adapted for use with a single-pole magnetic transducer head comprises a non-magnetic substrate having a surface, and a layer stack formed over the substrate surface, comprising, in overlying sequence from the substrate surface: (i) a magnetically soft underlayer (SUL) having a magnetic saturation value Ms and a thickness t; (ii) at least one non-magnetic interlayer; and (iii) at least one magnetically hard perpendicular recording layer; wherein the product Mst of the SUL is selected to have a minimum value which provides a desired amount of head field channeling but is sufficiently large to provide a desired reduction of erasure of written bits.

Abstract: A granular perpendicular magnetic recording medium comprises a non-magnetic substrate and a granular perpendicular magnetic recording layer overlying the substrate, comprising a first granular perpendicular magnetic layer proximal the substrate and having a first saturation magnetization (Ms)1, and a second granular perpendicular magnetic layer distal the substrate and having a second, different saturation magnetization (Ms)2. Also disclosed is a method of fabricating the granular perpendicular magnetic recording medium.

Abstract: Disclosed are granular magnetic recording media with improved grain segregation and corrosion resistance, comprising a non-magnetic substrate and at least one granular magnetic recording layer formed over the surface, comprised of at least one ferromagnetic material including magnetic grains with grain boundaries and a non-magnetic material comprised of a mixture of metal oxides. Also disclosed are methods for fabricating the improved media.

Abstract: A magnetic recording medium having a substrate and a SiO2-containing magnetic layer comprising grains is disclosed. The magnetic layer has substantial SiO2 between the grains. This condition is achieved by sputter depositing the magnetic layer in a chamber containing a gas under vacuum. The gas contains substantially no oxygen. Such a gas is one into which no oxygen is intentionally introduced to create an oxygen-containing gas mixture but may contain a trace amount of oxygen molecules in an amount that are present in air under a similar vacuum as that of the gas in the chamber.

Abstract: A magnetic recording medium with tuned exchange coupling comprises: (a) a non-magnetic substrate having a surface; and (b) a stack of thin film layers on the substrate surface, including: (i) a compositionally segregated, exchange decoupled magnetic layer with substantially non-magnetic grain boundaries; and (ii) an exchange coupled magnetic layer adjacent to and in direct contact with the exchange decoupled magnetic layer.

Abstract: A magnetic recording medium including at least one Cu-containing magnetic recording layer (CuML) comprised of a Cu-containing magnetic alloy material selected from the group consisting of: (a) a CoCrPtBCu alloy having a composition represented by the formula Co100-x-y-z-?CrxPtyBzCu60 , wherein 0<x?20, 0<y?30, 0<z?24, and 0<??10; (b) a CoCrPtBCu alloy having a composition represented by the formula Co100-x-y-z-?CrxPtyBzCu?, wherein 0<x?30, 0<y?30, 7<z?24, and 0<??10; and (c) a CoCrTaCu alloy having a composition represented by the formula Co100-x-y-?CrxTayCu?, containing less than 30 at. % Cr, up to 8 at. % Ta, and up to 10 at. % Cu.

Abstract: A magnetic recording medium, the order of layers in which is the substrate, the soft underlayer, the seedlayer, the 1st RuCrx-containing interlayer, the 2nd RuCrx-containing interlayer and the magnetic recording layer with preferably a oxides or nitrides-containing magnetic layer comprising grains, is disclosed. High-chromium ruthenium-chromium alloy used as inter layers significantly enhances coercivity and SMNR preferably due to the improved lattice match between RuCr inter layers and CoPt-based magnetic recording layers, and the surface energy of RuCr layers contributes to the performance improvement with the high-chromium addition into Ru inter layers.

Abstract: 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.

Abstract: A magnetic recording medium having a substrate and a SiO2-containing magnetic layer comprising grains is disclosed. The magnetic layer has substantial SiO2 between the grains. This condition is achieved by sputter depositing the magnetic layer in a chamber containing a gas under vacuum. The gas contains substantially no oxygen. Such a gas is one into which no oxygen is intentionally introduced to create an oxygen-containing gas mixture but may contain a trace amount of oxygen molecules in an amount that are present in air under a similar vacuum as that of the gas in the chamber.