A recording medium having improved signal-to-noise ratio (SNR) capabilities includes dual cap layers over the recording layer, where the Curie temperature of the first cap layer over the recording layer is greater than the Curie temperature of the recording layer, and the Curie temperature of the second cap layer over the first cap layer is greater than the Curie temperature of the first cap layer. The first cap layer may be composed of a magnetically hard material, such as L1.sub.0 CoPt, where the second cap layer may be composed of a magnetically soft material, such as Co. Such a medium is particularly useful in the context of heat-assisted magnetic recording (HAMR).

A magnetic recording medium includes a rigid substrate, an amorphous soft magnetic underlayer (SUL) on the substrate, a dead magnetic layer on the SUL, a seed layer on the dead magnetic layer, and a magnetic recording layer (MRL) on the seed layer. The dead magnetic layer is configured to provide an interdiffusion region between the amorphous SUL and seed layer with a saturation magnetic moment per unit area less than 510.sup.5 electromagnetic unit (emu)/cm.sup.2, and to produce a recording medium having an increase in tracks per inch (TPI) without significant reduction in bits per inch (BPI), and a net increase in areal density capacity (ADC) relative to a recoding medium that does not have the dead magnetic layer.

A magnetic recording medium includes a rigid substrate, an amorphous soft magnetic underlayer (SUL) on the substrate, a dead magnetic layer on the SUL, a seed layer on the dead magnetic layer, and a magnetic recording layer (MRL) on the seed layer. The dead magnetic layer is configured to provide an interdiffusion region between the amorphous SUL and seed layer with a saturation magnetic moment per unit area less than 510.sup.5 electromagnetic unit (emu)/cm.sup.2, and to produce a recording medium having an increase in tracks per inch (TPI) without significant reduction in bits per inch (BPI), and a net increase in areal density capacity (ADC) relative to a recoding medium that does not have the dead magnetic layer.

A magnetic recording medium includes a rigid substrate, an amorphous soft magnetic underlayer (SUL) on the substrate, a dead magnetic layer on the SUL, a seed layer on the dead magnetic layer, and a magnetic recording layer (MRL) on the seed layer. The dead magnetic layer is configured to provide an interdiffusion region between the amorphous SUL and seed layer with a saturation magnetic moment per unit area less than 510.sup.5 electromagnetic unit (emu)/cm.sup.2, and to produce a recording medium having an increase in tracks per inch (TPI) without significant reduction in bits per inch (BPI), and a net increase in areal density capacity (ADC) relative to a recoding medium that does not have the dead magnetic layer.

A magnetic recording medium includes a rigid substrate, an amorphous soft magnetic underlayer (SUL) on the substrate, a dead magnetic layer on the SUL, a seed layer on the dead magnetic layer, and a magnetic recording layer (MRL) on the seed layer. The dead magnetic layer is configured to provide an interdiffusion region between the amorphous SUL and seed layer with a saturation magnetic moment per unit area less than 510.sup.5 electromagnetic unit (emu)/cm.sup.2, and to produce a recording medium having an increase in tracks per inch (TPI) without significant reduction in bits per inch (BPI), and a net increase in areal density capacity (ADC) relative to a recoding medium that does not have the dead magnetic layer.

A method of manufacturing a magnetic recording medium including: forming a diffusion preventing layer, wherein the magnetic recording medium includes a non-magnetic substrate; an underlayer; a perpendicular magnetic layer; the diffusion preventing layer; and a protective layer, wherein 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 method of manufacturing a magnetic recording medium including: forming a diffusion preventing layer, wherein the magnetic recording medium includes a non-magnetic substrate; an underlayer; a perpendicular magnetic layer; the diffusion preventing layer; and a protective layer, wherein 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.

According to one embodiment, a perpendicular magnetic recording medium includes a substrate, an underlayer including projections arranged at an average interval of 3 to 20 nm, an amorphous magnetic recording layer having a plurality of columnar magnetic grains on the surface of the projections, each having a magnetization easy axis in a direction perpendicular to a surface of the underlayer. The underlayer is formed such that 0.5dr1.5d, where r is the radius of curvature of a vertical section of each projection and d is the average interval between the projections.

A perpendicular magnetic recording medium is disclosed in which crystal axis orientation dispersion, crystal grain diameter, and crystal grain diameter dispersion in a magnetic recording layer are reduced. The perpendicular magnetic recording medium has a structure having, stacked sequentially on a non-magnetic substrate, at least an amorphous underlayer, a lower orientation control layer made of Ru or Ru alloy of an hcp structure, an upper orientation control layer that is made of alloy containing an element selected from the group consisting of Co and Ni and an element selected from the group consisting of Cr, W, and Mo and that has an fcc or hcp structure, an intermediate layer, and a magnetic recording layer.

A perpendicular magnetic recording medium is disclosed in which crystal axis orientation dispersion, crystal grain diameter, and crystal grain diameter dispersion in a magnetic recording layer are reduced. The perpendicular magnetic recording medium has a structure having, stacked sequentially on a non-magnetic substrate, at least an amorphous underlayer, a lower orientation control layer made of Ru or Ru alloy of an hcp structure, an upper orientation control layer that is made of alloy containing an element selected from the group consisting of Co and Ni and an element selected from the group consisting of Cr, W, and Mo and that has an fcc or hcp structure, an intermediate layer, and a magnetic recording layer.