IP Library Granted Patent US 12,688,866
Granted Patent B2
US 12,688,866 · App. 18/986,106 · Granted Jul 21, 2026

Dynamic DC field compensator for MAMR recording head

Inventors: Alexander Goncharov (Morgan Hill, CA); Muhammad Asif Bashir (San Jose, CA); Yunfei Ding (Fremont, CA)
Assignee: Western Digital Technologies, Inc.
G11B5/3133G11B5/3143G11B2005/0024
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Quick Facts
Patent No.
US 12,688,866
App. No.
18/986,106
Granted
Jul 21, 2026
Kind
B2
Abstract

The present disclosure generally relates to a magnetic recording system comprising a magnetic recording head. The magnetic recording head comprises a main pole, a shield, and a spintronic device disposed between the main pole and the shield. The spintronic device comprises a field generation layer (FGL) spaced a distance of about 2 nm to about 3 nm from the main pole, a first spacer layer disposed on the FGL, a spin torque layer (STL) disposed on the first spacer layer, a second spacer layer disposed on the STL, and a negative polarization layer (NPL) disposed between the second spacer layer and the shield. The spintronic device has a length of about 17 nm to about 21. During operation, the STL has a magnetization precession of about 16 degrees to about 170 degrees, and the FGL has a magnetization precession of about 60 degrees to about 70 degrees.

Claims (54)

1 . A magnetic recording head, comprising:

a main pole;

a shield disposed adjacent to the main pole; and

a spintronic device disposed between the main pole and the shield, the spintronic device comprising:

a first notch disposed on the main pole;

a negative polarization layer (NPL) disposed on the first notch, the NPL comprising FeCr;

a first spacer layer disposed on the NPL;

a spin torque layer (STL) disposed on the first spacer layer;

a second spacer layer disposed on the STL;

a field generation layer (FGL) disposed on the second spacer layer;

a third spacer layer disposed on the FGL; and

a second notch disposed between and in contact with the third spacer layer and the shield.

2 . The magnetic recording head of claim 1 , wherein the first spacer layer comprises a first sublayer and a second sublayer, the first and second sublayer each individually comprising Cu, Ru, or a combination of one or more of Cu, Ru, and Cr.

3 . The magnetic recording head of claim 1 , wherein the spintronic device has a length of about 17 nm to about 21 nm, and wherein the third spacer layer has a thickness of about 2 nm to about 3 nm.

4 . The magnetic recording head of claim 1 , wherein the first notch comprises a magnetic material and the second notch comprises CoFe.

5 . A magnetic recording system comprising the magnetic recording head of claim 1 .

6 . The magnetic recording system of claim 5 , wherein the magnetic recording system is configured to apply a current to the magnetic recording head such that electrons flow from the main pole, through the spintronic device, to the shield.

7 . The magnetic recording system of claim 5 , wherein the STL is configured to apply torque to the FGL and to provide a direct current assist to enhance a recording field during operation.

8 . A magnetic recording head, comprising:

a main pole;

a shield disposed adjacent to the main pole; and

a spintronic device disposed between the main pole and the shield, the spintronic device comprising:

a first notch disposed in contact with the main pole;

a negative polarization layer (NPL) disposed in contact with the first notch, the NPL comprising FeCr;

a first spacer layer disposed in contact with the NPL;

a spin torque layer (STL) disposed in contact with the first spacer layer;

a second spacer layer disposed in contact with the STL;

a field generation layer (FGL) disposed in contact with the second spacer layer;

a third spacer layer disposed in contact with the FGL; and

a second notch disposed between and in contact with the third spacer layer and the shield, the second notch comprising CoFe.

9 . The magnetic recording head of claim 8 , wherein the FGL is spaced a distance of about 2 nm to about 3 nm from the shield.

10 . The magnetic recording head of claim 8 , wherein the first notch comprises a magnetic material, and wherein the first, second, and third spacer layers each individually comprise a non-magnetic material.

11 . The magnetic recording head of claim 8 , wherein the first spacer layer comprises a first sublayer and a second sublayer, the first and second sublayer each individually comprising Cu, Ru, or a combination of one or more of Cu, Ru, and Cr.

12 . A magnetic recording system comprising the magnetic recording head of claim 8 .

13 . The magnetic recording system of claim 12 , wherein the magnetic recording system is configured to apply a current to the magnetic recording head such that electrons flow from the main pole, through the spintronic device, to the shield.

14 . The magnetic recording system of claim 12 , wherein the STL is configured to apply torque to the FGL and to provide a direct current assist to enhance a recording field during operation.

15 . A magnetic recording head, comprising:

a main pole;

a shield disposed adjacent to the main pole; and

a spintronic device disposed between the main pole and the shield, the spintronic device comprising:

a first notch disposed on the main pole;

a negative polarization layer (NPL) disposed on the first notch, the NPL comprising FeCr;

a first spacer layer disposed on the NPL;

a spin torque layer (STL) disposed on the first spacer layer;

a second spacer layer disposed on the STL;

a field generation layer (FGL) disposed on the second spacer layer, wherein the FGL is spaced a distance of about 2 nm to about 3 nm from the shield;

a third spacer layer disposed on the FGL; and

a second notch disposed between and in contact with the third spacer layer and the shield, wherein the spintronic device has a length of about 17 nm to about 21 nm.

16 . The magnetic recording head of claim 15 , wherein the first notch comprises a magnetic material and the second notch comprises CoFe, and wherein the first, second, and third spacer layers each individually comprise a non-magnetic material.

17 . The magnetic recording head of claim 15 , wherein the first spacer layer comprises a first sublayer and a second sublayer, the first and second sublayer each individually comprising Cu, Ru, or a combination of one or more of Cu, Ru, and Cr.

18 . The magnetic recording head of claim 15 , wherein the FGL has a thickness of about 5 nm to about 10 nm, and wherein the STL has a thickness of about 4 nm to about 6 nm.

19 . A magnetic recording system comprising the magnetic recording head of claim 15 .

20 . The magnetic recording system of claim 19 , wherein the magnetic recording system is configured to apply a current to the magnetic recording head such that electrons flow from the main pole, through the spintronic device, to the shield.

21 . The magnetic recording system of claim 19 , wherein the STL is configured to apply torque to the FGL and to provide a direct current assist to enhance a recording field during operation.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 24, 2025
From: GONCHAROV, ALEXANDER; ASIF BASHIR, MUHAMMAD; DING, YUNFEI
To: WESTERN DIGITAL TECHNOLOGIES, INC.
Reel/Frame 070310/0346 →
SECURITY AGREEMENT (SUPPLEMENTAL) Recorded Feb 3, 2025
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A., AS AGENT
Reel/Frame 070088/0377 →
Continuity (3)
Division 18228523 · Jul 31, 2023
Provisional Application 63454171 · Mar 23, 2023
Related Publication 20250131942A1 · Apr 24, 2025
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