Dual pseudo spin valve heads

• US 20020018323A1
• Filed: 04/12/2001
• Published: 02/14/2002
• Est. Priority Date: 04/12/2000
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc), Seagate Technology plc (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Potter, Charles, Li, Shaoping
• Granted Patent: US 6,731,473 B2
• Time in Patent Office: Days
• US Class Current: 360/314
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: G01R 33/093 using multilayer structures, e.g. giant magnetoresistance sensors thin magnetic films H01F10/00
• CPC Class Codes: G11B 2005/3996 large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices
• CPC Class Codes: G11B 5/3903 using magnetic thin film layers or their effects, the films being part of integrated structures
• CPC Class Codes: G11B 5/3948 the sensitive elements being active read-out elements
• CPC Class Codes: Y10S 977/934 Giant magnetoresistance, GMR

Abstract

This invention presents a method and system for fabricating a dual GMR read head, which possess a pseudo spin valve structure. The spin valve structure includes a first thick Co-alloy based reference layer with first and second surfaces. The structure includes a first spacer layer including a first surface contacting the first surface of the first thick Co-alloy layer and a second surface contacting a first surface of a first free layer. The structure also includes a second spacer layer including a first surface separated from the second surface of the first free layer and a second surface contacting a first surface of a second thick Co-alloy layer. The thickness of the first and second thick Co-based alloy can be approximately between 30 and 55 Å.

Claims

1. A magnetoresistive sensor comprising:

a first thick Co-alloy based reference layer comprising opposing first and second surfaces;

a first spacer layer comprising a first surface contacting the first surface of the first thick Co-alloy layer and a second surface contacting a first surface of a first free layer; and

a second spacer layer comprising a first surface separated from the second surface of the first free layer and a second surface contacting a first surface of a second thick Co-alloy layer.

2. The magnetoresistive sensor of claim 1 additionally comprising:

a first Ru layer comprising a first surface contacting the first surface of the first thick Co-alloy layer and a second surface contacting a first surface of a first thin Co-alloy layer; and

a second Ru layer comprising a first surface contacting a second surface of the second thick Co-alloy layer and a second surface contacting a first surface of a second thin Co-alloy layer.

3. The magnetoresistive sensor of claim 1 additionally comprising:

an isolating layer comprising a first surface contacting the second surface of the first free layer and a second surface contacting a first surface of a second free layer;

wherein the second free layer additionally comprises a second surface contacting the first surface of the second spacer layer.

4. The magnetoresistive sensor of claim 3 wherein the isolating layer further comprises TaNi.

5. The magnetoresistive sensor of claim 3 additionally comprising:

an antiferromagnetic layer comprising a first surface contacting a second surface of the second thick Co-alloy layer.

6. The magnetoresistive sensor of claim 1 wherein the thickness of the first and second thick Co-based alloy is approximately between 30 and 55 Å

.

7. The magnetoresistive sensor of claim 1 wherein the first and second thick Co-based alloy comprises a material selected from the group consisting of CoFe, CoNiFe, CoCr, CoCrTa, CoPt, Co, FePt, CoXPt, and CoB/Pt.

8. The magnetoresistive sensor of claim 1 wherein the first and second spacer layers comprises a Cu-alloy.

9. The magnetoresistive sensor of claim 1 wherein the first and second free layer comprises NiFe.

10. A method of manufacturing a magnetoresistive sensor comprising:

forming a layered structure comprising;

a first thick Co-alloy layer comprising opposing first and second surfaces;

a first spacer layer comprising a first surface contacting the first surface of the first thick Co-alloy layer and a second surface contacting a first surface of a first free layer; and

a second spacer layer comprising a first surface separated from the second surface of the first free layer and a second surface contacting a first surface of a second thick Co-alloy layer.

11. The method of claim 10 additionally comprising:

depositing a first Ru layer comprising a first surface contacting the first surface of the first thick Co-alloy layer and a second surface contacting a first surface of a first thin Co-alloy layer; and

depositing a second Ru layer comprising a first surface contacting a second surface of the second thick Co-alloy layer and a second surface contacting a first surface of a second thin Co-alloy layer.

12. The method of claim 10 additionally comprising:

depositing an isolating layer comprising a first surface contacting the second surface of the first free layer and a second surface contacting a first surface of a second free layer;

wherein the second free layer additionally comprises a second surface contacting the first surface of the second spacer layer.

13. The method of claim 12 wherein the isolating layer further comprises TaNi.

14. The method of claim 12 additionally comprising:

depositing an antiferromagnetic layer comprising a first surface contacting a second surface of the second thick Co-alloy layer.

15. The method of claim 10 wherein the thickness of the first and second thick Co-based alloy is approximately between 30 and 55 Å

.

16. The method of claim 10 wherein the first and second thick Co-based alloy comprises a material selected from the group consisting of CoFe, CoNiFe, CoCr, CoCrTa, CoPt, Co, FePt, CoXPt, and CoB/Pt.

17. The method of claim 10 wherein the first and second spacer layers comprises a Cu-alloy.

18. The method of claim 10 wherein the first and second free layer comprises a NiFe.

19. A magnetoresistive sensor comprising:

a first and second spacer layer separated by a free layer; and

thick layer means for increasing the stability and reliability of the magnetoresistive sensor.