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Magnetic recording medium and magnetic recording and reproducing apparatus

A technology of magnetic recording medium and magnetic recording layer, applied in magnetic recording, data recording, recording information storage and other directions, can solve the problems of narrow material design space, affecting the recordability or stability of recording patterns, etc.

Active Publication Date: 2008-06-18
TOHOKU UNIV +2
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, in this case, since the magnetization caused by each magnetic grain becomes larger, the magnetostatic coupling between the magnetic grains affects the recordability or stability of the recorded pattern
Also, material design leeway becomes narrower

Method used

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  • Magnetic recording medium and magnetic recording and reproducing apparatus
  • Magnetic recording medium and magnetic recording and reproducing apparatus
  • Magnetic recording medium and magnetic recording and reproducing apparatus

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0100] In Example 1, LLG simulations were first performed to judge whether the coercive force Hc lowering effect in the present invention described above can occur within a certain practical range. The simulation results are shown in Figure 10.

[0101] In this simulation, the magnetic properties of the main recording layer were selected to have a magnetic anisotropy Ku of 6 Merg / cc and a saturation magnetization of 500 emu / cc. These values ​​are close to the characteristics of CoCrPt used in the magnetic recording layer of the perpendicular magnetic recording medium. The magnetic properties of the sub-recording layer are selected as magnetic anisotropy Ku4Merg / cc, saturation magnetization Ms1000emu / cc. These values ​​are close to the properties of CoIr. The exchange coupling constants within the magnetic crystal grains and between the main recording layer and the sub-recording layer were set to 0.5 µerg / cm. The grid size in the simulation is set to 1 cubic nanometer, and a...

example 2

[0112] In Example 2, based on the results in Example 1, a magnetic disk for a 2.5-inch hard disk drive described below was manufactured. First, a non-magnetic glass substrate (TS-10SX, manufactured by Ohara Inc.) was placed in the vacuum chamber of a sputtering system (type C-3010, manufactured by Canon ANELVA Company), and then, at 1 × 10 -6 The following layers were successively formed on the substrate in a vacuum of Pa: a soft magnetic underlayer composed of CoZrNb with a thickness of 100 nm, a Ta seed layer with a thickness of 5 nm, a Pt underlayer with a thickness of 10 nm, a Ru underlayer with a thickness of 10 nm, CoCrPt and SiO with thickness t1 = 18nm, 17nm, 15nm, 9nm, or 3nm 2 Main recording layer, Co with a thickness of (18-t1) = 0 nm, 1 nm, 3 nm, 9 nm, or 15 nm 80 Ir 20 Sub-recording layer, carbon protective layer with a thickness of 4nm. Next, remove the substrate on which the film layer sequence is formed from the vacuum chamber, and then cover the surface of ...

example 3

[0120] A magnetic recording medium was manufactured except that the thickness t1 of the main recording layer of the prepared sample was set to 9 nm, and the material constituting the sub-recording layer was CoFe, MnSb, FeC or Fe 3 The medium was the same as the magnetic recording medium in Example 2 except for Pt. The coercive force Hc of all these samples was 3 to 4 kOe, indicating that the coercive force Hc lowering effect was obtained.

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Abstract

The invention provides a magnetic recording medium, and a magnetic recording and reproducing apparatus. The magnetic recording medium includes a substrate 11, an under layer 12 formed on the substrate 11, a magnetic recording layer 13 formed on the under layer 12, and a protective layer 14 formed on the magnetic recording layer 13. The magnetic recording layer 13 is composed of a primary recording layer 14 and a secondary recording layer 15 which are mutually exchange-coupled. The primary recording layer 14 has magnetic grains and a nonmagnetic material that surrounds the magnetic grains, and has a perpendicular magnetic anisotropy. The secondary recording layer 15 is made of a material having a negative crystal magnetic anisotropy and its easy plane of the magnetization is a plane of the medium.

Description

[0001] Cross References to Related Applications [0002] Priority is claimed from Japanese Patent Application No. 2005-172601 filed on June 13, 2005. This application is an application made under 35 U.S.C. §111(a) and required under 35 U.S.C. §119(e) to obtain a provisional filed under 35 U.S.C. §111(b) on June 23, 2005 Filing date entitlement for application 60 / 693,091. technical field [0003] The present invention relates to a magnetic recording medium and a magnetic recording and reproducing apparatus. Background technique [0004] As computer processing speeds have increased over the past few years, faster recording speeds and higher recording densities are expected to be achieved in magnetic recording and reproducing devices capable of recording and retrieving data signals, such as hard disk drives (HDDs). Current HDDs use a longitudinal magnetic recording method in which the direction of magnetization lies in the plane of the magnetic recording medium. However, in ...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): G11B5/66G11B5/65G11B5/738H01F10/16H01F10/26H01F41/18
Inventor 高桥研冈正裕喜喜津哲
Owner TOHOKU UNIV
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