Magnetic recording medium and method for its production
AssigneeMitsubishi Chemical Corporation
InventorsMasahiro Oka, Fumiaki Yokoyama
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Abstract
A thin-film rigid disk magnetic medium is prepared having a non-magnetic substrate and a magnetic alloy layer formed on the substrate with a non-magnetic underlayer containing chromium as the main component interposed therebetween, where the magnetic alloy layer contains cobalt as the main component and not more than 8 atomic % of boron, not more than 40 atomic % of nickel, not more than 26 atomic % of chromium and not more than 10 atomic % of tantalum. Preferably, the magnetic alloy layer is formed by sputtering while a voltage relatively lower than the plasma potential is applied to the non-magnetic substrate.
Claims19
A metal thin film rigid disk magnetic medium, comprising:
- a non-magnetic disk shaped substrate;
- a Co-Cr-Ni-B-Ta magnetic alloy layer formed on said substrate;
- a non-magnetic underlayer containing chromium as the main component interposed therebetween;
- and
- wherein said magnetic alloy layer consists essentially of cobalt as the main component and not more than 8 atomic % of boron, not more than 40 atomic % of nickel, not more than 26 atomic % of chromium and not more than 10 atomic % of tantalum.
Dependencies are inferred from the claim text.