A fluorine-containing ether compound characterized by being represented by the following formula (1):

R.sup.1—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4—R.sup.5  (1)

In the formula (1), R.sup.3 is a perfluoropolyether chain. R.sup.2 and R.sup.4 are divalent linkage groups having a polar group and may be the same or different. R.sup.1 and R.sup.5 are bonded to an atom other than a carbon atom of R.sup.2 or R.sup.4. R.sup.1 and R.sup.5 are terminal groups composed of an organic group having 1 to 8 carbon atoms and may be the same or different. At least one of R.sup.1 and R.sup.5 is a chain organic group having 1 to 8 carbon atoms wherein one or more hydrogen atoms of the chain organic group is substituted with a group having an amide bond.

A magnetic recording medium includes a layer structure including a magnetic layer, a base layer, and a back layer in this order, in which an average thickness t.sub.T is t.sub.T≤5.5 μm, a dimensional variation Δw in a width direction to tension change in a longitudinal direction is 660 ppm/N≤Δw, and a surface roughness R.sub.abe of the base layer on a side of the back layer is 4.2 nm≤R.sub.abe≤8.5 nm.

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.

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 recording device comprising an overcoat layer, wherein the overcoat layer comprises an amorphous carbon overcoat layer having a crystallinity (C)≤0.8.

Systems and methods for treating a carbon overcoat surface are described. In one embodiment, the method may include depositing a magnetic recording layer over a substrate, depositing a carbon overcoat layer over the magnetic recording layer, and exposing a carbon overcoat layer to water in gas phase after the carbon overcoat layer is deposited on the magnetic recording layer. In some cases, the method may include depositing a lubricant over the outer surface of the carbon overcoat after exposing the carbon overcoat layer to the water in gas phase.

The present invention is to provide an assisted magnetic recording medium including a substrate; an underlayer disposed on the substrate; a magnetic layer disposed on the underlayer and including an alloy having an L1.sub.0-type crystal structure; and a pinning layer disposed in contact with the magnetic layer, wherein the pinning layer includes a granular structure, the granular structure containing magnetic particles and grain boundaries, wherein the magnetic particles contain Co, and wherein the grain boundaries contain Y.sub.2O.sub.3 and/or an oxide of lanthanoid.

There is provided a magnetic recording medium of which an average thickness t.sub.T is t.sub.T5.6 m, a dimensional change amount w in a width direction with respect to a change in tension in a longitudinal direction is 660 ppm/Nw, a squareness ratio in a vertical direction is 65% or more, and a width deformation coefficient b during long-term storage in a case where a long-term storage width change amount Y is defined as Y=blog(t) is 0.06 mb0.06 m.

There is provided a magnetic recording medium which has a layer structure including a magnetic layer and a base layer, and of which an average thickness t.sub.T is t.sub.T5.6 m, a dimensional change amount w in a width direction with respect to a change in tension in a longitudinal direction is 660 ppm/Nw, a servo pattern is recorded on the magnetic layer, a standard deviation PES of a position error signal (PES) value obtained from a servo signal in which the servo pattern is reproduced is PES25 nm, and a maximum value .sub.1M of a friction coefficient .sub.1 between a surface on a side of the magnetic layer and an LTO3 head in a case where measurement of the friction coefficient .sub.1 is performed 250 times is 0.04.sub.1M0.5.

The present disclosure relates to a magnetic recording medium for a magnetic media drive. Absorbing smears can develop on magnetic recording heads during operation. The absorbing smears lead to shortened drive lifetime. Transparent smears, on the other hand, do not have as deleterious of an impact on drive lifetime as compared to absorbing smears. By doping the medium with a dopant that can lead to development of transparent smears, the formation of absorbing smears can be reduced or even eliminated, which leads to a longer drive lifetime. The dopant can be disposed in the capping layer of the medium or in the absorbing overcoat layer. The dopant will migrate through the medium to the top surface of the medium during operation. From the top surface of the medium, the dopant will deposit on the magnetic head and form a transparent smear.