IP Library Granted Patent US 8,257,845
Granted Patent B2
US 8,257,845 · App. 12/378,120 · Granted Sep 4, 2012

Magnetic recording medium utilizing a recording layer having more and less concentrated parts of a nonmagnetic element in an in-plane direction and a nonmagnetic layer

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Quick Facts
Patent No.
US 8,257,845
App. No.
12/378,120
Granted
Sep 4, 2012
Kind
B2
Abstract

Embodiments of the present invention help to produce discrete track media and bit patterned media having both excellent recording and reproducing performance and reliability. According to one embodiment, a manufacturing method forms a nonmagnetic layer mainly composed of the same element as a nonmagnetic element contained in magnetic recording layers and on the magnetic recording layers and a mask layer having apertures for forming more concentrated parts of the nonmagnetic element in the magnetic recording layers on the nonmagnetic layer. The method implants ions of the nonmagnetic element through the nonmagnetic layer masked by the mask layer to form the more concentrated parts of the nonmagnetic element in the magnetic recording layer.

Claims (33)

1. A magnetic recording medium comprising:

a magnetic recording layer formed on a substrate and having at least two ferromagnetic alloy layers;

portions of the ferromagnetic alloy layers contain a nonmagnetic element arranged in an in-plane direction across the magnetic recording layer to define tracks without the nonmagnetic element and track separators with the nonmagnetic element, and the tracks and the track separators are co-planar with each other; and

the nonmagnetic element extends completely through the magnetic recording layer and partially into a layer beneath the magnetic recording layer.

2. New A magnetic recording medium according to claim 1 , further comprising a nonmagnetic layer on the magnetic recording layer, and the nonmagnetic element extends through the nonmagnetic layer as well.

3. A magnetic recording medium according to claim 2 , wherein the nonmagnetic layer is on top of the magnetic recording layer.

4. A magnetic recording medium according to claim 2 , wherein the nonmagnetic layer is between the ferromagnetic alloy layers.

5. A magnetic recording medium according to claim 2 , wherein the nonmagnetic layer has a thickness of 2 nm or less.

6. A magnetic recording medium according to claim 2 , wherein the nonmagnetic element and the nonmagnetic layer are different materials.

7. A magnetic recording medium according to claim 1 , wherein the portions of the ferromagnetic alloy layers are formed substantially concentrically.

8. A magnetic recording medium according to claim 1 , wherein the nonmagnetic element is selected from the group consisting of Cr, Mo, W, V, Nb, Ta, Ti, Zr, Hf, Ru, B, C, Si, and Ge.

9. A magnetic recording medium according to claim 1 , wherein the layer beneath the magnetic recording layer is a second orientation control layer.

10. A magnetic recording medium comprising:

a substrate;

an adhesion layer;

a first soft-magnetic layer;

an antiferromagnetie coupling layer;

a second soft magnetic layer;

an under layer;

a first orientation control layer;

a second orientation control layer;

a magnetic recording layer having at least two ferromagnetic alloy layers;

portions of the ferromagnetic alloy layers contain a nonmagnetic element arranged in an in-plane direction across the magnetic recording layer to define tracks without the nonmagnetic element and track separators with the nonmagnetic element, and the tracks and the track separators are co-planar with each other; and

the nonmagnetic element extends completely through the magnetic recording layer and partially into a layer beneath the magnetic recording layer.

11. A magnetic recording medium according to claim 10 , further comprising a nonmagnetic layer on the magnetic recording layer, and the nonmagnetic element extends through the nonmagnetic layer as well.

12. A magnetic recording medium according to claim 11 , wherein the nonmagnetic layer is on top of the magnetic recording layer.

13. A magnetic recording medium according to claim 11 , wherein the nonmagnetic layer is between the ferromagnetic alloy layers.

14. A magnetic recording medium according to claim 11 , wherein the nonmagnetic layer has a thickness of 2 mn or less.

15. A magnetic recording medium according to claim 11 , wherein the nonmagnetic element and the nonmagnetic layer are different materials.

16. A magnetic recording medium according to claim 10 , wherein the portions of the ferromagnetic alloy layers are formed substantially concentrically.

17. A magnetic recording medium according to claim 10 , wherein the nonmagnetic element is selected from the group consisting of Cr, Mo, W, V, Nb, Ta, Ti, Zr, Hf, Ru, B, C, Si, and Ge.

18. A magnetic recording medium according to claim 10 , wherein the layer beneath the magnetic recording layer is the second orientation control layer.

19. A magnetic recording medium according to claim 10 , wherein the layers are stacked on each other in the order in which they are listed.

Assignments (7)
PATENT COLLATERAL AGREEMENT - DDTL LOAN AGREEMENT Recorded Aug 21, 2023
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A.
Reel/Frame 067045/0156 →
PATENT COLLATERAL AGREEMENT - A&R LOAN AGREEMENT Recorded Aug 21, 2023
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A.
Reel/Frame 064715/0001 →
RELEASE OF SECURITY INTEREST AT REEL 052915 FRAME 0566 Recorded Feb 8, 2022
From: JPMORGAN CHASE BANK, N.A.
To: WESTERN DIGITAL TECHNOLOGIES, INC.
Reel/Frame 059127/0001 →
SECURITY INTEREST Recorded Feb 6, 2020
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A., AS AGENT
Reel/Frame 052915/0566 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 6, 2016
From: HGST NETHERLANDS B.V.
To: WESTERN DIGITAL TECHNOLOGIES, INC.
Reel/Frame 040826/0821 →
CHANGE OF NAME Recorded Oct 25, 2012
From: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
To: HGST NETHERLANDS B.V.
Reel/Frame 029341/0777 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 26, 2009
From: HINOUE, TATSUYA; KANAI, HIROSHI; ONO, TOSHINORI; SUZUKI, HIROYUKI; INABA, HIROSHI
To: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
Reel/Frame 022881/0364 →