IP Library Granted Patent US 9,245,567
Granted Patent B2
US 9,245,567 · App. 14/305,118 · Granted Jan 26, 2016

Magnetic recording medium and magnetic storage apparatus

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Quick Facts
Patent No.
US 9,245,567
App. No.
14/305,118
Granted
Jan 26, 2016
Kind
B2
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 .

Claims (38)

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.

Assignments (4)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 15, 2024
From: RESONAC CORPORATION
To: RESONAC HARD DISK CORPORATION
Reel/Frame 069167/0673 →
CHANGE OF ADDRESS Recorded Feb 14, 2024
From: RESONAC CORPORATION
To: RESONAC CORPORATION
Reel/Frame 066599/0037 →
CHANGE OF NAME Recorded Jun 23, 2023
From: SHOWA DENKO K.K.
To: RESONAC CORPORATION
Reel/Frame 064082/0513 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 16, 2014
From: KANBE, TETSUYA; NIWA, KAZUYA; MURAKAMI, YUJI; ZHANG, LEI
To: SHOWA DENKO K.K.
Reel/Frame 033109/0795 →