MAGNETIC RECORDING MEDIUM AND METHOD OF PRODUCING THE SAME

• US 20140342189A1
• Filed: 05/09/2014
• Published: 11/20/2014
• Est. Priority Date: 05/17/2013
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Tachibana, Junichi, Ito, Jota, Ozaki, Tomoe, Hiratsuka, Ryoichi, Sekiguchi, Noboru, Endo, Tetsuo
• Granted Patent: US 11,423,936 B2
• Time in Patent Office: Days
• US Class Current: 428/831
• CPC Class Codes: G11B 5/658 containing oxygen, e.g. molecular oxygen or magnetic oxide
• CPC Class Codes: G11B 5/7379 Seed layer, e.g. at least one non-magnetic layer is specifically adapted as a seed or seeding layer
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

There is provided a magnetic recording medium including a base; a seed layer; a foundation layer; and a recording layer, the seed layer being disposed between the base and the foundation layer, having an amorphous state, including an alloy containing Ti, Cr and O, a percentage of Ti being 30 atomic % to 100 atomic % based on a total amount of Ti and Cr contained in the seed layer, and a percentage of O being 15 atomic % or less based on a total amount of Ti, Cr and O contained in the seed layer. Also, a production method thereof is provided.

Claims

1. A magnetic recording medium, comprising:

a base;

a seed layer;

a foundation layer; and

a recording layer, the seed layer being disposed between the base and the foundation layer, having an amorphous state, including an alloy containing Ti, Cr and O, a percentage of Ti being 30 atomic % to 100 atomic % based on a total amount of Ti and Cr contained in the seed layer, and a percentage of O being 15 atomic % or less based on a total amount of Ti, Cr and O contained in the seed layer.

2. The magnetic recording medium according to claim 1, wherein

the seed layer decreases irregularities on the surface of the base.

3. The magnetic recording medium according to claim 1, wherein

the foundation layer includes Ru.

4. The magnetic recording medium according to claim 1, wherein

the foundation layer includes a first foundation layer and a second foundation layer, and

the first foundation layer is disposed at a recording layer side and includes Ru.

5. The magnetic recording medium according to claim 1, wherein

the recording layer has a granular structure where particles containing Co, Pt and Cr are separated by an oxide.

6. The magnetic recording medium according to claim 5, wherein

the recording layer has an average composition shown by the following chemical formula (1):

(Co_xPt_yCr_100-x-y)_100-z—

(SiO₂)_z 

 

(1)

(in the formula (1), x, y and z have a value of 69≦

x≦

72, 12≦

y≦

16, 9≦

z≦

12).

7. The magnetic recording medium according to claim 1, further comprising:

another seed layer disposed between the seed layer and the foundation layer.

8. The magnetic recording medium according to claim 1, further comprising:

a soft magnetic layer disposed between the seed layer and the foundation layer.

9. The magnetic recording medium according to claim 8, wherein

a film thickness of the soft magnetic layer is 40 nm to 140 nm.

10. The magnetic recording medium according to claim 8, wherein

the soft magnetic layer includes a first soft magnetic layer, an intermediate layer and a second soft magnetic layer, and

the intermediate layer is disposed between the first magnetic layer and the second magnetic layer.

11. The magnetic recording medium according to claim 8, further comprising:

another seed layer disposed between the soft magnetic layer and the foundation layer.

12. The magnetic recording medium according to claim 1, further comprising:

a layer containing Co, Cr and Pt disposed on the recording layer.

13. The magnetic recording medium according to claim 1, wherein

the seed layer, the foundation layer and the recording layer are sequentially formed by a roll-to-roll method.

14. A magnetic recording medium, comprising:

a base;

a seed layer;

a foundation layer; and

a recording layer, the seed layer being disposed between the base and the foundation layer, having an amorphous state, including an alloy containing Ti and Cr, and a percentage of Ti being 30 atomic % to 100 atomic % based on a total amount of Ti and Cr contained in the seed layer.

15. A magnetic recording medium, comprising:

a base;

a layer having an amorphous state and containing Ti and Cr;

a foundation layer; and

a recording layer, the layer containing Ti and Cr being disposed between the base and the foundation layer, and a percentage of Ti in the layer containing Ti and Cr being 30 atomic % to 100 atomic % based on a total amount of Ti and Cr.

16. A method of producing a magnetic recording medium, comprising:

sequentially forming a seed layer, a foundation layer and a recording layer on a base by a roll-to-roll method, the seed layer having an amorphous state and including an alloy containing Ti, Cr and O, a percentage of Ti being 30 atomic % to 100 atomic % based on a total amount of Ti and Cr contained in the seed layer, and a percentage of O being 15 atomic % or less based on a total amount of Ti, Cr and O contained in the seed layer.

17. A method of producing a magnetic recording medium, comprising:

laminating a plurality of thin-films on a surface of a base while the base is transferred along a periphery of a rotator, at least two layer of a plurality of the thin-films being sequentially formed.

18. The method of producing a magnetic recording medium according to claim 17, wherein

a temperature of the rotator is desirably 10°

C. or less,

the periphery of the rotator is contacted with the base having an angle of 220°

or more,

a tensile force of the base is 4 g/mm or more per 1 mm width, and

a maximum dynamic rate of a plurality of the thin-films is 70 nm·

m/min or less.

19. The method of producing a magnetic recording medium according to claim 17, wherein

a plurality of the thin-films include a seed layer, a foundation layer and a recording layer.

20. The method of producing a magnetic recording medium according to claim 19, wherein

a plurality of the thin-films further include a soft magnetic layer.