Hitachi, Ltd.

Shoichi Sawahata

Hideaki Tanaka

Yoshiki Kato

Masaki Ohura

Yoshihiko Miyake

Kenichi Gomi

Noriaki Okamoto

Norikazu Tsumita

Youichi Inomata

Hiroshi Yashiki

Nobuo Nakagawa

Toyoji Okuwaki

Yoshihiro Moriguchi

Hiroyuki Sugimoto

Katuo Uda

Maki Kondo

A magnetic disk has a magnetic layer and a protective layer disposed on the magnetic layer. A multiplicity of lands having sizes within a predetermined range of sizes and generally equal heights within a predetermined range are formed on the surface of the protective layer at a density within a predetermined range. The lands serve to effectively remove contaminants attached to the floating surface of a magnetic head to ensure a desired sliding reliability and floating stability of the head during a long period of time even in the case of a high-density magnetic disk apparatus in which the extent of floating of the head is small. The reliability with which the magnetic disk apparatus operates is thereby improved. The lands are formed on the surface of the protective layer by a process of forming a mask of fine particles on the protective layer surface and etching the protective layer surface through this mask.

Magnetic disk, method of manufacturing the same and magnetic disk

There is provided a magnetic disk apparatus including at least one magnetic disk having a magnetic layer and a surface protective layer on a substrate; a magnetic head which faces the magnetic disk in a rotating state with a micro gap and is supported by a slider; rotating means for rotating the magnetic disk; and magnetic head positioning means for moving and positioning the magnetic head to a predetermined position on the magnetic disk, wherein a plurality of protrusions each having a flat surface are formed in at least a region on the surface of the magnetic disk where a contact start/stop operation can be executed, an area ratio of the protrusions per 1 mm.sup.2 lies within a range from 0.1 to 80%, a height of the protrusion of the maximum height among the protrusions lies within a range from 5 to 40 nm, and the magnetic layer is formed on the whole surface on the base plate. According to the above magnetic disk apparatus, the frictional force between the disk and the head is small, and the floating height of the head can be reduced, and good floating stability is obtained, so that excellent recording and reproducing characteristics are obtained.

Magnetic disk with surface protective layer having convex portions and

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Hitachi, Japan

Shoichi Sawahata