A magnetic recording medium includes a substrate, an underlayer provided above the substrate, and a magnetic layer provided on and in contact with the underlayer. The underlayer includes a compound represented by a general formula MgO.sub.(1-x), where x falls within a range of 0.07 to 0.25. The magnetic layer includes an alloy having a L1.sub.0 structure, and the alloy having the L1.sub.0 structure includes one or more elements selected from a group consisting of Al, Si, Ga, and Ge.

The present disclosure generally related to read heads having dual free layer (DFL) sensors. The read head has a sensor disposed between two shields. The sensor is a DFL sensor and has a surface at the media facing surface (MFS). Behind the DFL sensor, and away from the MFS, is a rear hard bias (RHB) structure. The RHB structure is disposed between the shields as well. In between the DFL sensor and the RHB structure is insulating material. The RHB is disposed on the insulating material. The RHB includes a RHB seed layer as well as a RHB bulk layer. The RHB seed layer has a thickness of between 26 Angstroms and 35 Angstroms. The RHB seed layer ensures the read head has a strong RHB magnetic field that can be uniformly applied.

A sputtering target according to the present invention contains Co and Pt as metal components, wherein a molar ratio of a content of Pt to a content of Co is from 5/100 to 45/100, and wherein the sputtering target contains Nb.sub.2O.sub.5 as a metal oxide component.

A sputtering target according to the present invention contains Co and Pt as metal components, wherein a molar ratio of a content of Pt to a content of Co is from 5/100 to 45/100, and wherein the sputtering target contains Nb.sub.2O.sub.5 as a metal oxide component.

The present invention relates to a magnetic recording medium including a substrate; an underlayer laminated upon the substrate; and a magnetic layer laminated upon the underlayer, wherein the underlayer includes a first underlayer containing a compound represented by a following general formula: MgO.sub.(1-X), where X is within a range of 0.07 to 0.25, the magnetic layer includes a first magnetic layer containing an alloy having a L1.sub.0 structure, and the alloy having the L1.sub.0 structure includes B, and the first underlayer is in contact with the first magnetic layer.

The present invention relates to a magnetic recording medium including a substrate; an underlayer laminated upon the substrate; and a magnetic layer laminated upon the underlayer, wherein the underlayer includes a first underlayer containing a compound represented by a following general formula: MgO.sub.(1-X), where X is within a range of 0.07 to 0.25, the magnetic layer includes a first magnetic layer containing an alloy having a L1.sub.0 structure, and the alloy having the L1.sub.0 structure includes B, and the first underlayer is in contact with the first magnetic layer.

Magnetic media including a magnetic recording layer structure formed of alternating magnetic recording sublayers and non-magnetic exchange control sublayers. The magnetic recording layer structure may include at least one magnetic recording sublayer formed to include a pair of thin films, with the films having different concentrations of platinum, ruthenium, and/or oxide segregants. That is, the sublayer has a “dual layer” structure. The dual layer structure can provide a gradient in magnetic anisotropy, saturation magnetization, and/or intergranular magnetic exchange coupling across the sublayer. In some examples, the film nearer to the substrate of the magnetic media has a higher platinum concentration than the other film. In one aspect, the magnetic media includes the substrate and the magnetic recording layer structure on the substrate, with the structure including six magnetic recording sublayers. In another aspect, a method of fabricating magnetic media with such structures is provided.

A sputtering target for magnetic recording media capable of producing a magnetic thin film in which the magnetic crystal grains are micronized and the distance between the centers of the grains is reduced while good magnetic properties are maintained. The target including metallic Pt and an oxide, with the balance being metallic Co and inevitable impurities, wherein the Co is contained in a range of 70 at % to 90 at % and the Pt is contained in a range of 10 at % to 30 at % relative to a total of metallic components in the sputtering target for magnetic recording media, the oxide is contained in a range of 26 vol % to 40 vol % relative to a total volume of the sputtering target for magnetic recording media, and the oxide is composed of B.sub.2O.sub.3 and one or more high-melting-point oxides having a melting point of 1470° C. or higher and 2800° C. or lower.

Provided is an FePt based magnetic material sintered compact, comprising BN and SiO.sub.2 as non-magnetic materials, wherein Si and O are present in a region where B or N is present at a cut surface of the sintered compact. A high density sputtering target is provided which enables production of a magnetic thin film for heat-assisted magnetic recording media, and also reduces the amount of particles generated during sputtering.

Provided is an FePt based magnetic material sintered compact, comprising BN and SiO.sub.2 as non-magnetic materials, wherein Si and O are present in a region where B or N is present at a cut surface of the sintered compact. A high density sputtering target is provided which enables production of a magnetic thin film for heat-assisted magnetic recording media, and also reduces the amount of particles generated during sputtering.