Canted easy axis in self-pinned layers
View Patent ↗A magnetic head having a free layer and an antiparallel (AP) pinned layer structure spaced apart from the free layer, the AP pinned layer structure including at least two AP-pinned layers having magnetic moments that are self-pinned antiparallel to each other, the AP-pinned layers being separated by an AP coupling layer. An easy axis of a first or both of the AP-pinned layers is oriented at an angle of at least 5° from the ABS along a plane of the first AP-pinned layer.
1. A magnetic head having an air bearing surface (ABS), comprising:
a free layer; and
an antiparallel (AP) pinned layer structure spaced apart from the free layer, the AP pinned layer structure including at least two AP-pinned layers having magnetic moments that are self-pinned antiparallel to each other, the AP-pinned layers being separated by an AP coupling layer;
wherein an easy axis of a first of the AP-pinned layers is oriented at an angle of at least 5° from the ABS along a plane of the first AP-pinned layer.
2. A head as recited in claim 1 , wherein an easy axis of each of the AP-pinned layers is oriented at an angle of at least 5° from the ABS along a plane of the associated AP-pinned layer.
3. A head as recited in claim 1 , wherein the easy axis of the first AP-pinned layers is oriented at an angle of between about 30° and about 60° from the ABS along a plane of the first AP-pinned layer.
4. A head as recited in claim 1 , wherein the easy axis of the first AP-pinned layer is oriented at an angle of between about 40° and about 50° from the ABS along a plane of the first AP-pinned layer.
5. A head as recited in claim 1 , wherein easy axes of the AP pinned layers are oriented at about the same angle.
6. A head as recited in claim 1 , wherein easy axes of the AP pinned layers are oriented at different angles.
7. A head as recited in claim 1 , wherein the easy axis is set by forming the first AP-pinned layer in the presence of an applied magnetic field having flux oriented at an angle of at least 5° from the ABS along the plane of the first AP-pinned layer.
8. A head as recited in claim 1 , wherein the AP pinned layer structure is self pinned, the AP pinned layer structure not being stabilized by an antiferromagnet.
9. A head as recited in claim 1 , wherein the magnetizations of the AP-pinned layers are oriented perpendicular to the ABS.
10. A head as recited in claim 1 , further comprising an AFM layer.
11. A head as recited in claim 1 , wherein the easy axis of the first AP-pinned layer is oriented at an angle of between about 5° and about 45° from the ABS along a plane of the first AP-pinned layer.
12. A head as recited in claim 1 , wherein the head is a CPP GMR sensor.
13. A head as recited in claim 1 , wherein the head is a CPP tunnel valve sensor.
14. A head as recited in claim 1 , wherein the head is a CIP sensor.
15. A magnetic head having an air bearing surface (ABS), comprising:
a free layer; and
an antiparallel (AP) pinned layer structure spaced apart from the free layer, the AP pinned layer structure including at least two AP-pinned layers having magnetic moments that are self-pinned antiparallel to each other, the AP-pinned layers being separated by an AP coupling layer;
wherein the easy axes of the AP-pinned layers are oriented at an angle of between about 30° and about 60° from the ABS along a plane of the associated AP-pinned layer.
16. A head as recited in claim 15 , wherein the easy axis of each of the AP-pinned layers is oriented at an angle of between about 40° and about 50° from the ABS along a plane of the associated AP-pinned layer.
17. A head as recited in claim 15 , wherein the angle of each of the easy axes is about the same.
18. A head as recited in claim 15 , wherein the angles of the easy axes are different.
19. A head as recited in claim 15 , wherein the easy axis is set by forming the AP-pinned layers in the presence of an applied magnetic field having flux oriented at an angle of between about 30° and about 60° from the ABS along the plane of the first AP-pinned layer.
20. A head as recited in claim 15 , wherein the AP pinned layer structure is self pinned, the AP pinned layer structure not being stabilized by an antiferromagnet.
21. A head as recited in claim 15 , wherein the magnetizations of the AP-pinned layers are oriented perpendicular to the ABS.
22. A head as recited in claim 15 , further comprising an AFM layer.
23. A head as recited in claim 22 , wherein the easy axis of the first AP-pinned layer is oriented at an angle of between about 5° and about 45° from the ABS along a plane of the first AP-pinned layer.
24. A head as recited in claim 15 , wherein the head is a CPP GMR sensor.
25. A head as recited in claim 15 , wherein the head is a CPP tunnel valve sensor.
26. A head as recited in claim 15 , wherein the head is a CIP sensor.
27. A magnetic storage system, comprising:
magnetic media;
at least one head for reading from and writing to the magnetic media, each head having:
a free layer; and
an antiparallel (AP) pinned layer structure spaced apart from the free layer, the AP pinned layer structure including at least two AP-pinned layers having magnetic moments that are self-pinned antiparallel to each other, the AP-pinned layers being separated by an AP coupling layer;
wherein an easy axis of a first of the AP-pinned layers is oriented at an angle of at least 5° from the ABS along a plane of the first AP-pinned layer;
a slider for supporting the head; and
a control unit coupled to the head for controlling operation of the head.