IP Library Granted Patent US 9,934,810
Granted Patent B2
US 9,934,810 · App. 14/220,332 · Granted Apr 3, 2018

Magnetic recording medium and magnetic storage apparatus

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Quick Facts
Patent No.
US 9,934,810
App. No.
14/220,332
Granted
Apr 3, 2018
Kind
B2
Abstract

A magnetic recording medium includes a substrate, multiple underlayers formed on the substrate, and a magnetic layer formed on the multiple underlayers. A main component of the magnetic layer is an alloy having a L1 0 structure. At least one of the multiple underlayers is a crystalline underlayer containing W. The W is a main component of the crystalline underlayer. The crystalline underlayer further contains 1 mol % or more to 20 mol % or less of one or more kinds of elements selected from B, Si, and C. A barrier layer including a material having a NaCl structure is formed between the crystalline underlayer and the magnetic layer.

Claims (19)

1. A magnetic recording medium comprising:

a substrate;

a plurality of underlayers formed on the substrate; and

a magnetic layer formed on the plurality of underlayers;

wherein a main component of the magnetic layer is an alloy having a L1 0 structure,

wherein at least one of the plurality of underlayers is a crystalline underlayer containing W,

wherein the W is a main component of the crystalline underlayer,

wherein the W contained in the crystalline underlayer is 80 at % or more,

wherein the crystalline underlayer further contains 1 mol % or more to 20 mol % or less of one or more kinds of elements selected from B, Si, and C,

wherein a barrier layer including a material having a NaCl structure is formed between the crystalline underlayer and the magnetic layer.

2. The magnetic recording medium as claimed in claim 1 , further comprising:

an orientation control underlayer including one or more kinds of metal selected from Cr, an alloy having a BCC structure and including Cr as a main component, and an alloy having a B2 structure;

wherein the crystalline underlayer is formed on the orientation control underlayer.

3. The magnetic recording medium as claimed in claim 1 , wherein the material having a NaCl structure includes one or more kinds of compounds selected from MgO, TiO, NiO, TiN, TiC, TaN, HfN, NbN, ZrC, HfC, TaC, and NbC.

4. The magnetic recording medium as claimed in claim 1 ,

wherein the magnetic layer includes one or more kinds of substances selected from 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, B 2 O 3 , C, B, and BN,

wherein a main component of the magnetic layer is a FePt alloy having a L1 0 structure or a CoPt alloy.

5. A magnetic storage apparatus comprising:

the magnetic recording medium of claim 1 .

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 Mar 20, 2014
From: ZHANG, LEI; KANBE, TETSUYA; MURAKAMI, YUJI; NIWA, KAZUYA
To: SHOWA DENKO K.K.
Reel/Frame 032487/0192 →