Method for providing an improved AFM reader shield

• US 9,431,047 B1
• Filed: 06/25/2013
• Issued: 08/30/2016
• Est. Priority Date: 05/01/2013
• Status: Active Grant

• Current Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Original Assignee: Western Digital (Fremont) LLC (Western Digital Corporation)
• Inventors: Xiao, Rongfu
• Primary Examiner(s): Ahmed, Shamim
• Assistant Examiner(s): Gates, Bradford
• Application Number:
  US13/927,007
• Time in Patent Office: 1,162 Days
• US Class Current: 1/1
• 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 5/3909 Arrangements using a magnetic tunnel junction
• CPC Class Codes: G11B 5/3912 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 Class Codes: G11B 5/852 Orientation in a magnetic field G11B5/845 takes precedence

Abstract

A method provides a magnetic transducer including a first shield, a read sensor, and a second shield. The read sensor is between the first shield and the second shield. The read sensor has at least one pinned layer aligned with a sensor pinning direction. Providing the second shield includes depositing at least one of a first ferromagnetic layer, a second ferromagnetic and a pinning layer in the presence of a first magnetic field in a first direction non-orthogonal and non-parallel to the sensor pinning direction. A nonmagnetic spacer layer is between the first ferromagnetic layer and the second ferromagnetic layer. The pinning layer is adjacent to the second ferromagnetic layer. The first ferromagnetic layer is between the read sensor and the nonmagnetic spacer layer. The first ferromagnetic layer is coupled antiparallel with the second ferromagnetic layer.

Claims

1. A method for providing a magnetic read transducer having an air-bearing surface (ABS) comprising:

providing a first shield;

providing a read sensor, the read sensor having at least one pinned layer aligned with a sensor pinning direction; and

providing a second shield, the read sensor residing between the first shield and the second shield, the at least one pinned layer being closer to the first shield than to the second shield, the step of providing the second shield further including

depositing a first ferromagnetic layer, a second ferromagnetic layer and a pinning layer, at least one of the first ferromagnetic layer, the second ferromagnetic layer and the pinning layer being deposited in the presence of a first magnetic field in a first direction non-orthogonal and non-parallel to the sensor pinning direction, a nonmagnetic spacer layer residing between the first ferromagnetic layer and the second ferromagnetic layer, the pinning layer being adjacent to the second ferromagnetic layer, the first ferromagnetic layer residing between the read sensor and the nonmagnetic spacer layer, the first ferromagnetic layer being coupled antiparallel with the second ferromagnetic layer.

2. The method of claim 1 wherein the step of providing the second shield further includes:

annealing the second shield in a second magnetic field, the second magnetic field being aligned with the first direction.

3. The method of claim 1 wherein the first direction is at least forty-five degrees and not more than seventy degrees from the sensor pinning direction.

4. The method of claim 3 wherein the first direction is at least fifty degrees and not more than sixty degrees from the sensor pinning direction.

5. The method of claim 1 further comprising:

providing a hard bias structure adjacent to the sensor, the hard bias structure having a magnetic moment aligned in a hard bias direction, the hard bias direction being substantially perpendicular to the sensor pinning direction.

6. The method of claim 1 further comprising:

providing a soft bias structure adjacent to the sensor, the soft bias structure having a magnetic moment that is magnetically coupled with the second shield.

7. The method of claim 1 wherein the nonmagnetic spacer layer includes Ru.

8. The method of claim 7 wherein the nonmagnetic spacer layer has a thickness of at least four Angstroms and not more than ten Angstroms.

9. The method of claim 7 wherein the first ferromagnetic layer and the second ferromagnetic layer each include NiFe.

10. The method of claim 1 wherein the first ferromagnetic layer includes a NiFe layer and a CoFe layer, the CoFe layer residing between the NiFe layer and the nonmagnetic spacer layer.

11. The method of claim 1 wherein the second ferromagnetic layer includes a NiFe layer and a CoFe layer, the CoFe layer residing between the NiFe layer and the nonmagnetic layer.

12. The method of claim 11 wherein the second ferromagnetic layer includes an additional CoFe layer, the NiFe layer being between the CoFe layer and the additional CoFe layer.

13. The method of claim 1 wherein the first ferromagnetic layer, the second ferromagnetic layer and the pinning layer are deposited in the presence of the magnetic field.

14. The method of claim 1 wherein the pinning layer includes an antiferromagnetic layer.

15. The method of claim 1 wherein the step of providing the second shield further includes:

providing the second shield such that the magnetic read transducer is free of ferromagnetic materials between the free layer and the second shield.

16. A method for providing a magnetic read transducer having an air-bearing surface (ABS) comprising:

providing a first shield;

providing a read sensor, the read sensor having at least one pinned layer aligned with a sensor pinning direction;

providing a soft bias structure adjacent to the sensor, the soft bias structure having a magnetic moment; and

providing a second shield, the read sensor residing between the first shield and the second shield, the at least one pinned layer being closer to the first shield than to the second shield, the step of providing the second shield further including

depositing a first ferromagnetic layer, a second ferromagnetic layer and a pinning layer in the presence of a first magnetic field in a first direction, the first direction being at least fifty-five and not more than sixty degrees from the sensor pinning direction;

depositing a nonmagnetic spacer layer between the first ferromagnetic layer and the second ferromagnetic layer, the pinning layer being adjacent to the second ferromagnetic layer, the first ferromagnetic layer residing between the read sensor and the nonmagnetic spacer layer, the first ferromagnetic layer being coupled antiparallel with the second ferromagnetic layer, the nonmagnetic spacer layer including a Ru layer having a thickness of at least four and not more than ten Angstroms; and

annealing the second shield in a second magnetic field, the second magnetic field being aligned with the first direction.

17. The method of claim 16 wherein the first ferromagnetic layer includes a NiFe layer and a CoFe layer, the CoFe layer residing between the NiFe layer and the nonmagnetic spacer layer.

18. The method of claim 16 wherein the second ferromagnetic layer includes a NiFe layer and a CoFe layer, the CoFe layer residing between the NiFe layer and the nonmagnetic spacer layer.

19. The method of claim 16 wherein the nonmagnetic spacer layer is Ru.

20. A method for providing a magnetic read transducer having an air-bearing surface (ABS) comprising:

providing a first shield;

providing a read sensor, the read sensor having at least one pinned layer aligned with a sensor pinning direction;

providing a magnetic bias structure adjacent to the sensor; and

providing a second shield, the read sensor residing between the first shield and the second shield, the at least one pinned layer being closer to the first shield than to the second shield, the step of providing the second shield further including

depositing a first ferromagnetic layer in the presence of a first magnetic field in a first direction non-orthogonal and non-parallel to the sensor pinning direction;

depositing a nonmagnetic spacer layer;

depositing a second ferromagnetic in the presence of a second magnetic field in the first direction, the nonmagnetic spacer layer being between the first ferromagnetic layer and the second ferromagnetic layer, the first ferromagnetic layer being coupled antiparallel with the second ferromagnetic layer; and

depositing a pinning layer in the presence of a third magnetic field in the first direction; and

annealing the second shield in a fourth magnetic field, the fourth magnetic field being aligned with the first direction.

21. The method of claim 20 wherein the first direction is at least fifty-five and not more than sixty degrees from the sensor pinning direction.