Lubricated and overcoated magneto-optical media with improved tribological performance
AssigneeSeagate Technology LLC
InventorGa-Lane Chen
Life of this patent
Estimating the term…
Abstract
Magneto-optical information storage media having improved tribological properties when used in high-density storage devices employing very small head flying heights are formed by providing by a protective overcoat/lubricant topcoat layer system on the media surface. Embodiments of the present invention include forming the protective overcoat layer of an amorphous, abrasion resistant, carbon-based, diamond-like material less than about 50 Å thick selected from CNx, CHx, and CNxHy, and forming the lubricant topcoat at a thickness of 15-25 Å, of a medium molecular weight linear chain perfluoro polyalkylene polymer having reactive end groups for bonding the polymer molecules to the protective overcoat layer.
Claims19
A magneto-optical storage medium comprising a laminate including at least one magneto-optic read/write layer formed over a substrate and covered by a dielectric layer which is transparent to the wavelength(s) of at least one laser beam used for writing and reading out information stored in said medium, said medium further comprising:
- an amorphous, abrasion resistant, carbon-based protective overcoat layer having a thickness less than about 50 Å over said transparent dielectric layer;
- and
- a perfluoropolyether-based lubricant topcoat layer having a thickness of from about 15 to about 25 Å on said protective overcoat layer.
A magneto-optical medium comprising a laminate including at least one magneto-optic writing layer formed over a substrate and covered by a dielectric layer which is transparent to the wavelength(s) of at least one laser beam used for writing and reading-out information stored in said medium, said disc further comprising:
- an amorphous, abrasion resistant, carbon-based, protective overcoat layer over said transparent dielectric layer, said protective overcoat layer having a thickness less than about 50 Å and comprising a material selected from the group consisting of:
- a-CNx, a-CHx, and a-CNxHy;
- and
- a lubricant topcoat layer having a thickness of from about 15 Å to about 25 Å on said protective overcoat layer, said lubricant topcoat layer comprising a linear chain perfluoro polyalkylene polymer having the structural formula:
- X—CF2—[(OCF2—CF2)m—(OCF2)n]—OCF2—X,
- wherein:
- n and m are each in the range from about 5 to about 30, n/m is approximately 1, and X is a reactive end group selected from
Dependencies are inferred from the claim text.