IP Library Granted Patent US 9,007,880
Granted Patent B2
US 9,007,880 · App. 14/385,840 · Granted Apr 14, 2015

Thermally assisted magnetic recording medium and magnetic recording and reproducing apparatus

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Quick Facts
Patent No.
US 9,007,880
App. No.
14/385,840
Granted
Apr 14, 2015
Kind
B2
Abstract

A thermally assisted magnetic recording medium ( 1 ) includes a substrate ( 101 ), an underlayer ( 3 ) that is formed above the substrate ( 101 ), and a magnetic layer ( 107 ) that is formed on the underlayer ( 3 ) and contains an alloy having an L1 0 structure as a main component. The underlayer ( 3 ) is formed by continuously laminating a first underlayer ( 104 ) having a BCC structure with a lattice constant that is 0.302 to 0.332 nm, a second underlayer ( 105 ) that has a NaCl structure including C, and a third underlayer ( 106 ) that is composed of MgO.

Claims (21)

1. A thermally assisted magnetic recording medium comprising:

a substrate;

an underlayer that is formed above the substrate; and

a magnetic layer that is formed on the underlayer and contains an alloy having an L1 0 structure as a main component,

wherein the underlayer is formed by continuously laminating a first underlayer having a BCC structure with a lattice constant that is 0.302 to 0.332 nm, a second underlayer that has an NaCl structure including C, and a third underlayer that is composed of MgO.

2. The thermally assisted magnetic recording medium according to claim 1 ,

wherein the first underlayer includes at least one of elements which are selected from the group consisting of Mo, W, Nb, and Ta.

3. The thermally assisted magnetic recording medium according to claim 1 ,

wherein the first underlayer is composed of one material selected from the group consisting of Mo, W, Nb, and Ta.

4. The thermally assisted magnetic recording medium according to claim 1 ,

wherein the second underlayer is composed of one material selected from the group consisting of TaC, NbC, ZrC, and HfC.

5. The thermally assisted magnetic recording medium according to claim 1 ,

wherein the second underlayer is composed of TaC or NbC.

6. The thermally assisted magnetic recording medium according to claim 1 ,

wherein the magnetic layer has a FePt or CoPt alloy having the L1 0 structure as a main component and includes at least one material selected from the group 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.

7. A magnetic recording and reproducing apparatus comprising:

the thermally assisted magnetic recording medium according to claim 1 ,

a medium driving unit that drives the magnetic recording medium in a recording direction;

a magnetic head that includes a laser generation unit configured to heat the magnetic recording medium and a waveguide configured to guide a laser beam generated from the laser generation unit to a leading end, and performs a recording operation and a reproducing operation on the magnetic recording medium;

a head moving unit that moves the magnetic head relative to the magnetic recording medium; and

a recording and reproducing signal processing system that inputs a signal to the magnetic head and reproduces a signal output from the magnetic head.

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 Sep 19, 2014
From: KANBE, TETSUYA; NIWA, KAZUYA; MURAKAMI, YUJI; ZHANG, LEI
To: SHOWA DENKO K.K.
Reel/Frame 033778/0722 →