Patent classifications
G11B5/657
MAGNETIC RECORDING MEDIUM AND MAGNETIC STORAGE APPARATUS
A magnetic recording medium includes a substrate, an underlayer, and a magnetic layer that are arranged in this order. The magnetic layer has a granular structure including magnetic grains having a L1.sub.0 crystal structure, and grain boundary parts having a volume fraction in a range of 25 volume % to 50 volume %. The magnetic grains have a c-axis orientation with respect to the substrate. The grain boundary parts include a material having a lattice constant in a range of 0.30 nm to 0.36 nm, or in a range of 0.60 nm to 0.72 nm.
Perpendicular magnetic recording medium
The magnetic recording medium includes at least a nonmagnetic substrate and a magnetic recording layer, the magnetic recording layer consists of a first magnetic recording layer or a plurality of layers including at least the first magnetic recording layer and a second magnetic recording layer, the first magnetic recording layer has a granular structure including a first magnetic crystal grain and a first nonmagnetic crystal grain boundary, the first magnetic crystal grain consists of an ordered alloy having Fe, Pt and Rh, the first nonmagnetic crystal grain boundary consists of carbon, boron or a combination thereof, the second magnetic recording layer has a granular structure including a second magnetic crystal grain and a second nonmagnetic crystal grain boundary, the second magnetic crystal grain consists of an FePt ordered alloy or an ordered alloy having Fe, Pt and Rh, and the second nonmagnetic crystal grain boundary includes carbon.
Heat-assisted magnetic recording (HAMR) medium with improved corrosion resistance
A heat-assisted magnetic recording (HAMR) medium has a heat-sink layer, a chemically-ordered FePt (or CoPt) alloy magnetic layer and a MgNiO intermediate layer between the heat-sink layer and the magnetic layer. The intermediate layer is a solid substitution crystalline alloy of the form (Mg.sub.(100-y)Ni.sub.y)O, where y is less than 10 and greater than or equal to 0.5. The magnetic layer may be formed directly on the MgNiO intermediate layer, in which case the MgNiO intermediate layer functions as both a seed layer and a thermal barrier layer. The HAMR medium may also include an optional layer of crystalline pure MgO directly below or directly above the MgNiO intermediate layer. If the MgO layer is located directly above the MgNiO intermediate layer then the MgNiO intermediate layer functions primarily as a thermal barrier layer. The HAMR medium with the MgNiO intermediate layer provides a substantial improvement in corrosion resistance.
MAGNETIC RECORDING MEDIUM AND MAGNETIC STORAGE APPARATUS
A magnetic recording medium includes: a substrate; an underlayer; and a magnetic layer including an alloy having a L1.sub.0 structure and a (001) orientation, wherein the substrate, the underlayer, and the magnetic layer are stacked in the recited order, and wherein the magnetic layer has a granular structure and includes a carbon hydride, a boron hydride, or a boron nitride hydride.
MAGNETIC RECORDING MEDIUM AND MAGNETIC STORAGE APPARATUS
A magnetic recording medium includes a nonmagnetic substrate, a soft magnetic underlayer, an orientation control layer, a perpendicular magnetic layer, and a protection layer that are arranged in this order. The perpendicular magnetic layer includes a first magnetic layer and a second magnetic layer that are arranged in this order on the orientation control layer. The first magnetic layer has a granular structure including an oxide at grain boundary parts of magnetic grains, and the second magnetic layer is closest to the protection layer among layers within the perpendicular magnetic layer, and includes magnetic grains made of a CoCrPt alloy, and a nitride of carbon or a hydride of carbon.
Recording medium
A recording medium is provided, such as paper, secured by magnetic microwires. The recording medium comprises: a pulp structure formed by pulp fibers, said pulp structure carrying microwires having a metal core of a predetermined material composition, and an insulating layer coating on said metal core; and at least one coating layer on at least one side of said pulp structure. The pulp structure is a single-layer structure with the microwires fully embedded in said single layer, the microwires having cross-sectional dimensions approximately equal to cross-sectional dimensions of the pulp fibers.
Granularity in overlying magnetic and non-magnetic layers
Provided herein is an apparatus including a layer stack. A first granular metal layer overlies the layer stack, wherein the first granular metal layer includes first metal grains separated by voids. A first granular non-metal layer overlies the first granular metal layer, wherein the first granular non-metal layer includes first non-metal grains separated by a first segregant. A second granular non-metal layer overlies the first granular non-metal layer, wherein the second granular non-metal layer includes second non-metal grains separated by a second segregant. A second granular metal layer overlies the second granular non-metal layer, wherein the second granular metal layer includes second metal grains separated by a third segregant.
Sputtering target for forming magnetic recording film and process for producing same
A C-containing FePt-based sputtering target for forming a magnetic recording film, wherein a ratio of an X-ray diffraction peak intensity of a graphite (002) plane in a cross section perpendicular to a sputtering surface relative to an X-ray diffraction peak intensity of a graphite (002) plane in a plane horizontal to a sputtering surface is 2 or more. A magnetic recording layer is configured from a magnetic phase such as an FePt alloy and a nonmagnetic phase that separates the magnetic phase, and the sputtering target is a ferromagnetic material sputtering target in which carbon is used as a nonmagnetic phase material. When sputtered, the ferromagnetic material sputtering target is effective in preventing the generation of particles caused by an abnormal discharge originating from carbon, which is prone to aggregate.
Magnetic recording medium
The purpose of the invention is to provide a magnetic recording medium in which the surface roughness of the magnetic recording layer can be reduced without deterioration of the magnetic properties of the magnetic recording layer. The magnetic recording medium of the present invention includes a substrate, a seed layer on the substrate, and a magnetic recording layer on the seed layer, wherein the seed layer contains Mn, Cr, and O, and has a spinel structure.
Dual phase MgO-X seed layers for heat assisted magnetic recording media
Magnetic media having dual phase MgO-X seed layers with both MgO grains and segregants are provided. One such magnetic medium includes a substrate, a heatsink layer on the substrate, a dual phase seed layer on the heatsink layer, where the dual phase seed layer comprises MgO and a segregant, where a concentration of the MgO is greater than 50 percent by volume in the dual phase seed layer, and a magnetic recording layer including FePt on the dual phase seed layer.