Soft underlayer having a multilayer structure for high areal density perpendicular recording media
AssigneeHGST Netherlands B.V.
InventorsThomas C. Arnoldussen, Jack Jyh-Kau Chang, Arien M. Ghaderi, Zhupei Shi
Life of this patent
Estimating the term…
Abstract
According to one embodiment, a soft underlayer structure includes a coupling layer, at least one outer soft underlayer positioned above and below the coupling layer, and at least one inner soft underlayer positioned above and below the coupling layer between the coupling layer and the associated outer soft underlayer, where the inner soft underlayers have a saturation magnetic flux density and/or a thickness that is different than a saturation magnetic flux density and/or a thickness of the outer soft underlayers.
Claims20
A soft underlayer structure, comprising:
- a coupling layer,
- at least one outer soft underlayer positioned above and below the coupling layer, and
- at least one inner soft underlayer positioned above and below the coupling layer between the coupling layer and the associated outer soft underlayer,
- wherein the inner soft underlayers have a saturation magnetic flux density and/or a thickness that is different than a saturation magnetic flux density and/or a thickness of the outer soft underlayers.
A product, comprising:
- a soft underlayer structure, comprising:
- a coupling layer,
- at least one outer soft underlayer positioned above and below the coupling layer, and
- at least one inner soft underlayer positioned above and below the coupling layer between the coupling layer and the associated outer soft underlayer,
- wherein the inner soft underlayers have a saturation magnetic flux density and/or a thickness that is different than a saturation magnetic flux density and/or a thickness of the outer soft underlayers;
- and
- a recording layer above the soft underlayer structure.
Dependencies are inferred from the claim text.