Non-localized spin valve multi-free-layer reader hybridized with spin orbit torque layers

Patent metadata

Field	Value
Publication number	US-12412597-B2
Application number	US-202318367882-A
Country	US
Kind code	B2
Filing date	Sep 13, 2023
Priority date	Jun 26, 2023
Publication date	Sep 9, 2025
Grant date	Sep 9, 2025

Abstract

The present disclosure generally relates to a magnetic recording head comprising a read head. The read head comprises a first sensor disposed at a media facing surface (MFS) comprising at least one free layer, a second sensor disposed at the MFS comprising at least one free layer, a first spin generator spaced from the first sensor and recessed from the MFS, and a second spin generator spaced from the second sensor and recessed from the MFS. The first and second spin generators each individually comprises at least one spin orbit torque (SOT) layer. The SOT layer may comprise BiSb. The first and second sensors are configured to detect a read signal using a first voltage lead and a second voltage lead. The first and second spin generators are configured to inject spin current through non-magnetic layers to the first and second sensors using a plurality of current leads.

First claim

What is claimed is:

1. A read head, comprising:
a first shield;
a second shield;
a first non-magnetic layer disposed between the first shield and the second shield;
a first sensor disposed between the first non-magnetic layer and the second shield at a media facing surface (MFS), the first sensor comprising a first free layer;
a first spin generator recessed from the MFS, the first spin generator being spaced from the first sensor wherein the first spin generator comprises a first seed layer, a first non-magnetic spin orbit torque (SOT) layer, and a first cap layer;
a third shield disposed over the second shield;
a second non-magnetic layer disposed between the second shield and the third shield;
a second sensor disposed between the second non-magnetic layer and the third shield at the MFS, the second sensor comprising a second free layer; and
a second spin generator recessed from the MFS, the second spin generator being spaced from the second sensor, wherein the second spin generator comprises a second seed layer, a second non-magnetic SOT layer, and a second cap layer.

2. The read head of claim 1 , further comprising:
a first magnetic notch disposed between the first non-magnetic layer and the first shield; and
a second magnetic notch disposed between the second non-magnetic layer and the second shield.

3. The read head of claim 1 , further comprising:
a fourth shield disposed between the second shield and the second non-magnetic layer; and
an insulating layer disposed between the second shield and the fourth shield.

4. The read head of claim 3 , further comprising:
a first negative voltage lead connected to the first shield;
a first positive voltage lead connected to the second shield;
a second negative voltage lead connected to the fourth shield; and
a second positive voltage lead connected to the third shield.

5. The read head of claim 3 , further comprising:
a first positive current lead connected to the first non-magnetic SOT layer;
a first negative current lead connected to the first non-magnetic SOT layer;
a second positive current lead connected to the second non-magnetic SOT layer; and
a second negative current lead connected to the second non-magnetic SOT layer.

6. The read head of claim 1 , further comprising:
a first soft bias side shield disposed adjacent to the first sensor at the MFS;
a second soft bias side shield disposed adjacent to the first sensor at the MFS, wherein the first sensor is disposed between the first soft bias side shield and the second soft bias side shield;
a third soft bias side shield disposed adjacent to the second sensor at the MFS; and
a fourth soft bias side shield disposed adjacent to the second sensor at the MFS, wherein the second sensor is disposed between the third soft bias side shield and the fourth soft bias side shield.

7. The read head of claim 1 , wherein the first spin generator is disposed between the first non-magnetic layer and the second shield, and wherein the second spin generator disposed is between the second non-magnetic layer and the third shield.

8. A magnetic recording head comprising the read head of claim 1 .

9. A magnetic recording device comprising the magnetic recording head of claim 8 .

10. A magnetic recording head, comprising:
a read head, the read head comprising:
a first shield, the first shield comprising a first shield notch;
a second shield disposed over the first shield;
a first non-magnetic layer disposed between the first shield notch and the second shield;
a first sensor disposed between the first non-magnetic layer and the second shield at a media facing surface (MFS), the first sensor comprising a first free layer;
a first spin generator disposed between the first shield and the second shield recessed from the MFS, the first spin generator being spaced from the first sensor, wherein the first spin generator comprises:
a first seed layer;
a first non-magnetic spin orbit torque (SOT) layer disposed between the first shield and the first non-magnetic layer;
a second non-magnetic SOT layer disposed between the first non-magnetic layer and the second shield; and
a first cap layer;

a third shield disposed over the second shield, the third shield comprising a second shield notch;
a fourth shield disposed over the third shield;
a second non-magnetic layer disposed between the second shield notch and the fourth shield;
a second sensor disposed between the second non-magnetic layer and the fourth shield at the MFS, the second sensor comprising a second free layer; and
a second spin generator disposed between the third shield and the fourth shield recessed from the MFS, the second spin generator being spaced from the second sensor, wherein the second spin generator comprises:
a second seed layer;
a third non-magnetic SOT layer disposed between the third shield and the second non-magnetic layer;
a fourth non-magnetic SOT layer disposed between the second non-magnetic layer and the fourth shield; and
a second cap layer.

11. The magnetic recording head of claim 10 , wherein the read head further comprises:
a first magnetic notch disposed between the first shield notch and the first non-magnetic layer;
a second magnetic notch disposed between the second shield notch and the third shield;
a first soft bias (SB) side shield disposed adjacent to the first free layer;
a second SB side shield disposed adjacent to the first free layer;
a third SB side shield disposed adjacent to the second free layer; and
a fourth SB side shield disposed adjacent to the second free layer.

12. The magnetic recording head of claim 11 , wherein the read head further comprises:
a first negative current lead connected to the first magnetic notch;
a first positive current lead connected to the second shield;
a second negative current lead connected to the second magnetic notch; and
a second positive current lead connected to the fourth shield.

13. The magnetic recording head of claim 10 , wherein:
the first non-magnetic SOT layer is disposed adjacent to the first shield notch;
the second non-magnetic SOT layer is disposed adjacent to the first free layer;
the third non-magnetic SOT layer is disposed adjacent to the second shield notch; and
the fourth non-magnetic SOT layer is disposed adjacent to the second free layer.

14. The magnetic recording head of claim 10 , wherein the read head further comprises:
a first negative voltage lead connected to the first shield;
a first positive voltage lead connected to the second shield;
a second negative voltage lead connected to the third shield; and
a second positive voltage lead connected to the fourth shield.

15. The magnetic recording head of claim 10 , wherein the read head further comprises:
a first negative current lead connected to the first non-magnetic SOT layer;
a first positive current lead connected to the first non-magnetic SOT layer;
a second positive current lead connected to the second non-magnetic SOT layer;
a second negative current lead connected to the second non-magnetic SOT layer;
a third negative current lead connected to the third non-magnetic SOT layer;
a third positive current lead connected to the third non-magnetic SOT layer;
a fourth positive current lead connected to the fourth non-magnetic SOT layer; and
a fourth negative current lead connected to the fourth non-magnetic SOT layer.

16. The magnetic recording head of claim 10 , wherein the read head further comprises:
a first negative current lead connected to the first shield;
a first positive current lead con

Assignees

• Western Digital Tech Inc
• Tokyo Inst Tech

Inventors

• Le Quang
• Liu Xiaoyong
• York Brian R
• Hwang Cherngye
• Le Son T
• Takano Hisashi
• Tuo FAN
• Osman Hassan
• Pham Nam Hai

Classifications

• G11B5/3909

  Arrangements using a magnetic tunnel junction · CPC title

• G11B5/3912 Primary

  Arrangements in which the active read-out elements are transducing in association with active magnetic shields, e.g. magnetically coupled shields (G11B5/3916 takes precedence) · CPC title

• G11B2005/3996

  large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices · CPC title

• G11B5/3954 Primary

  the active elements transducing on a single track · CPC title