IP Library Patent Application 11789297
Patent Application
App. No. 11/789,297

Magnetic recording medium, recording apparatus, and method and apparatus for manufacturing magnetic recording medium

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Quick Facts
Patent No.
US None
App. No.
11/789,297
Abstract

A magnetic recording medium includes a substrate, an underlayer of a chromium alloy formed on the substrate, a ferromagnetic layer formed on the underlayer, a spacer layer formed on the ferromagnetic layer, and a recording layer of a cobalt-chromium alloy formed on the spacer layer. The spacer layer is formed with a ruthenium-cobalt-based alloy.

Claims (24)

1 . A magnetic recording medium comprising:

a substrate;

an underlayer of a chromium alloy formed on the substrate;

a ferromagnetic layer formed on the underlayer;

a spacer layer formed on the ferromagnetic layer; and

a recording layer of a cobalt-chromium alloy formed on the spacer layer, wherein

the spacer layer is formed with a ruthenium-cobalt-based alloy.

2 . The magnetic recording medium according to claim 1 , wherein the spacer layer contains 40% to 80% of cobalt.

3 . The magnetic recording medium according to claim 1 , wherein a thickness of the spacer layer is in a range from 0.3 nanometer to 2 nanometers.

4 . The magnetic recording medium according to claim 1 , wherein a crystal lattice size of the spacer layer is equal to or larger than that of the ferromagnetic layer and equal to or smaller than that of the recording layer.

5 . A recording apparatus comprising:

a magnetic recording medium that includes

a substrate,

an underlayer of a chromium alloy formed on the substrate,

a ferromagnetic layer formed on the underlayer,

a spacer layer of a ruthenium-cobalt-based alloy formed on the ferromagnetic layer, and

a recording layer of a cobalt-chromium alloy formed on the spacer layer; and

a magnetic head that performs reading or writing of magnetic data with respect to the magnetic recording medium.

6 . A method of manufacturing a magnetic recording medium comprising:

forming an underlayer by coating a chromium alloy film on a substrate;

forming a ferromagnetic layer on the underlayer;

forming a spacer layer by coating a ruthenium-cobalt-based alloy film on the ferromagnetic layer; and

forming a recording layer by coating a cobalt-chromium alloy film on the spacer layer.

7 . An apparatus for manufacturing a magnetic recording medium by sequentially forming an underlayer of a chromium alloy, a ferromagnetic layer, a spacer layer, and a recording layer of a cobalt-chromium alloy on a substrate, wherein the spacer layer is made of a ruthenium-cobalt-based alloy.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 4, 2010
From: FUJITSU LIMITED
To: SHOWA DENKO K.K.
Reel/Frame 023950/0008 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 24, 2007
From: SHIDA, KAZUHISA; YOSHIDA, YUKI; TAGUCHI, JUN; ASAKURA, NORIYUKI; KIKUCHI, AKIRA
To: FUJITSU LIMITED
Reel/Frame 019234/0569 →