A magnetic recording medium including: a non-magnetic substrate; an underlayer; a perpendicular magnetic layer; a diffusion preventing layer; and a protective layer, wherein the underlayer, the perpendicular magnetic layer, the diffusion preventing layer, and the protective layer are layered on the non-magnetic substrate in this order, the perpendicular magnetic layer has a multi-layer structure, the perpendicular magnetic layer includes an uppermost layer and at least one layer other than the uppermost layer, the uppermost layer including Co or Fe in magnetic particles, and the at least one layer other than the uppermost layer including an oxide, the diffusion preventing layer is provided between the perpendicular magnetic layer and the protective layer, and the diffusion preventing layer includes at least one component selected from a group consisting of Si, Ti, Cr, B, and Ru, or either a carbide, an oxide, or both, of the at least one component.

A sputtering target for a magnetic recording medium, comprises: a metal phase containing Pt and at least one or more selected from Mn and V, with the balance being Co and incidental impurities; and an oxide phase containing at least B and O.

Magnetic recording media including an interlayer configured to reduce lattice mismatch with adjacent layers of the media, such as an adjacent seed layer or an adjacent underlayer. In one example, an interlayer alloy is provided that includes tungsten (W) along with Cobalt (Co), Chromium (Cr), and Ruthenium (Ru). The atomic percentages of W and Ru within the interlayer are selected so that the amount lattice mismatch between the interlayer and its adjacent layers is below a preselected amount, such as below 3% as quantified by d-spacing. In some examples, the atomic percentage of Ru is greater than 25% and the atomic percentage of W is 2-10%. Methods of fabricating the magnetic recording media are also provided.

Magnetic recording media including an interlayer configured to reduce lattice mismatch with adjacent layers of the media, such as an adjacent seed layer or an adjacent underlayer. In one example, an interlayer alloy is provided that includes tungsten (W) along with Cobalt (Co), Chromium (Cr), and Ruthenium (Ru). The atomic percentages of W and Ru within the interlayer are selected so that the amount lattice mismatch between the interlayer and its adjacent layers is below a preselected amount, such as below 3% as quantified by d-spacing. In some examples, the atomic percentage of Ru is greater than 25% and the atomic percentage of W is 2-10%. Methods of fabricating the magnetic recording media are also provided.

A magnetic recording medium including: a non-magnetic substrate; an underlayer; a perpendicular magnetic layer; a diffusion preventing layer; and a protective layer, wherein the underlayer, the perpendicular magnetic layer, the diffusion preventing layer, and the protective layer are layered on the non-magnetic substrate in this order, the perpendicular magnetic layer has a multi-layer structure, the perpendicular magnetic layer includes an uppermost layer and at least one layer other than the uppermost layer, the uppermost layer including Co or Fe in magnetic particles, and the at least one layer other than the uppermost layer including an oxide, the diffusion preventing layer is provided between the perpendicular magnetic layer and the protective layer, and the diffusion preventing layer includes at least one component selected from a group consisting of Si, Ti, Cr, B, and Ru, or either a carbide, an oxide, or both, of the at least one component.

A magnetic recording medium including: a non-magnetic substrate; an underlayer; a perpendicular magnetic layer; a diffusion preventing layer; and a protective layer, wherein the underlayer, the perpendicular magnetic layer, the diffusion preventing layer, and the protective layer are layered on the non-magnetic substrate in this order, the perpendicular magnetic layer has a multi-layer structure, the perpendicular magnetic layer includes an uppermost layer and at least one layer other than the uppermost layer, the uppermost layer including Co or Fe in magnetic particles, and the at least one layer other than the uppermost layer including an oxide, the diffusion preventing layer is provided between the perpendicular magnetic layer and the protective layer, and the diffusion preventing layer includes at least one component selected from a group consisting of Si, Ti, Cr, B, and Ru, or either a carbide, an oxide, or both, of the at least one component.

A magnetic recording medium includes a magnesium oxide underlayer including magnesium oxide, and a magnetic layer including an alloy having a L1.sub.0 structure and includes Fe or Co and Pt. The magnesium oxide has a peak of an O1s spectrum detected in a range of 531 eV to 533 eV when measured by X-ray photoelectron spectroscopy.

A magnetic recording medium includes a magnesium oxide underlayer including magnesium oxide, and a magnetic layer including an alloy having a L1.sub.0 structure and includes Fe or Co and Pt. The magnesium oxide has a peak of an O1s spectrum detected in a range of 531 eV to 533 eV when measured by X-ray photoelectron spectroscopy.

An object is to suppress or prevent a dimensional change of a magnetic recording tape.

The present technology provides a magnetic recording tape having a layer structure including a magnetic layer, a base layer, and a back layer in this order, in which a reinforcing layer containing a metal or a metal oxide is disposed on either a surface of the base layer on the magnetic layer side or a surface of the base layer on the back layer side, and a black area in an image obtained by binarizing an optical microscope image of a rectangular region of 64 μm×48 μm of the reinforcing layer is 300 μm.sup.2 or less. Furthermore, the present technology also provides a magnetic recording tape having a layer structure including a magnetic layer, a base layer, and a back layer in this order, in which a reinforcing layer containing a metal or a metal oxide is disposed on either a surface of the base layer on the magnetic layer side or a surface of the base layer on the back layer side, and the number of black regions in an image obtained by binarizing an optical microscope image of a rectangular region of 64 μm×48 μm of the reinforcing layer is 70 or less.

An object is to suppress or prevent a dimensional change of a magnetic recording tape.

The present technology provides a magnetic recording tape having a layer structure including a magnetic layer, a base layer, and a back layer in this order, in which a reinforcing layer containing a metal or a metal oxide is disposed on either a surface of the base layer on the magnetic layer side or a surface of the base layer on the back layer side, and a black area in an image obtained by binarizing an optical microscope image of a rectangular region of 64 μm×48 μm of the reinforcing layer is 300 μm.sup.2 or less. Furthermore, the present technology also provides a magnetic recording tape having a layer structure including a magnetic layer, a base layer, and a back layer in this order, in which a reinforcing layer containing a metal or a metal oxide is disposed on either a surface of the base layer on the magnetic layer side or a surface of the base layer on the back layer side, and the number of black regions in an image obtained by binarizing an optical microscope image of a rectangular region of 64 μm×48 μm of the reinforcing layer is 70 or less.