Magnetic recording medium and magnetic storage apparatus

Patent metadata

Field	Value
Publication number	US-9245567-B2
Application number	US-201414305118-A
Country	US
Kind code	B2
Filing date	Jun 16, 2014
Priority date	Jun 20, 2013
Publication date	Jan 26, 2016
Grant date	Jan 26, 2016

Abstract

A magnetic recording medium includes a substrate, a magnetic layer including a FePt alloy having a L1 0 type structure, and a plurality of underlayers arranged between the substrate and the magnetic layer, wherein at least one of the plurality of underlayers includes TiO 2 .

First claim

What is claimed is:

1. A magnetic recording medium comprising:
a substrate;
a magnetic layer including a FePt alloy having a L1 0 type structure; and
a plurality of underlayers arranged between the substrate and the magnetic layer,
wherein at least a first underlayer amongst the plurality of underlayers consists of TiO 2 , and
wherein the magnetic layer is provided directly on the first underlayer.

2. The magnetic recording medium as claimed in claim 1 , wherein
the plurality of underlayers includes a second underlayer made of Cr or an alloy having a BCC (Body-Centered Cubic) structure and including Cr as a primary component of the alloy, and
the first underlayer is provided on the second underlayer.

3. The magnetic recording medium as claimed in claim 1 , wherein
the plurality of underlayers includes a second underlayer made of a material having a BCC (Body-Centered Cubic) structure, and
the first underlayer is provided on the second underlayer.

4. The magnetic recording medium as claimed in claim 1 , wherein
the plurality of underlayers includes a second underlayer made of a material having an NaCl type structure, and
the first underlayer is provided on the second underlayer.

5. The magnetic recording medium as claimed in claim 4 , wherein the material is MgO.

6. The magnetic recording medium as claimed in claim 1 , wherein the first underlayer is made of rutile type TiO 2 , and has an orientation in which a (100) face is parallel to a surface of the substrate.

7. The magnetic recording medium as claimed in claim 1 , wherein the magnetic layer includes the FePt alloy having the L1 0 type structure as a primary component of the magnetic layer, and one or more kinds of elements selected from a group of elements consisting of SiO 2 , TiO 2 , Cr 2 O 3 , Al 2 O 3 , Ta 2 O 5 , ZrO 2 , Y 2 O 3 , CeO 2 , MnO, TiO, ZnO, C, B, B 2 O 3 , and BN.

8. The magnetic recording medium as claimed in claim 1 , wherein the magnetic layer includes
a first magnetic layer including the FePt alloy having the L1 0 type structure as a primary component of the first magnetic layer, and TiO 2 amounting to 8 mol % or higher and 30 mol % or lower, and
a second magnetic layer including the FePt alloy having the L1 0 type structure as a primary component of the second magnetic layer, and one or more kinds of elements selected from a group of elements consisting of SiO 2 , TiO 2 , Cr 2 O 3 , Al 2 O 3 , Ta 2 O 5 , ZrO 2 , Y 2 O 3 , CeO 2 , MnO, TiO, ZnO, C, B, B 2 O 3 , and BN.

9. A magnetic storage apparatus comprising:
a magnetic recording medium; and
a magnetic head configured to recording information on and reproduce information from the magnetic recording medium,
wherein the magnetic recording medium includes a substrate, a magnetic layer including a FePt alloy having a L1 0 type structure, and a plurality of underlayers arranged between the substrate and the magnetic layer, and
wherein at least a first underlayer amongst the plurality of underlayers consists of TiO 2 , and
wherein the magnetic layer is provided directly on the first underlayer.

10. The magnetic storage apparatus as claimed in claim 9 , wherein
the plurality of underlayers includes a second underlayer made of Cr or an alloy having a BCC (Body-Centered Cubic) structure and including Cr as a primary component of the alloy, and
the first underlayer is provided on the second underlayer.

11. The magnetic storage apparatus as claimed in claim 9 , wherein
the plurality of underlayers includes a second underlayer made of a material having a BCC (Body-Centered Cubic) structure, and
the first underlayer is provided on the second underlayer.

12. The magnetic storage apparatus as claimed in claim 9 , wherein
the plurality of underlayers includes a second underlayer made of a material having an NaCl type structure, and
the first underlayer is provided on the second underlayer.

13. The magnetic storage apparatus as claimed in claim 12 , wherein the material is MgO.

14. The magnetic storage apparatus as claimed in claim 9 , wherein the first underlayer is made of rutile type TiO 2 , and has an orientation in which a (100) face is parallel to a surface of the substrate.

Assignees

• Showa Denko Kk

Inventors

• Kanbe Tetsuya
• Niwa Kazuya
• Murakami Yuji
• Zhang Lei

Classifications

• G11B5/738 Primary

  Physics · mapped topic

• G11B5/7325

  Physics · mapped topic

• G11B5/66

  the record carriers consisting of several layers · CPC title

• G11B5/65

  characterised by its composition (G11B5/66 takes precedence) · CPC title

• G11B5/7369 Primary

  Two or more non-magnetic underlayers, e.g. seed layers or barrier layers · CPC title