Magnetic devices having a hard bias field and magnetic memory devices using the magnetic devices
View Patent ↗A method and system for providing a magnetic memory device are disclosed. The method and system include providing a magnetic element that includes a data storage layer having at least one easy axis in at least a first direction. The method and system also include providing a hard bias structure surrounding a portion of the magnetic element. The hard bias structure is also configured to provide at least one hard bias field essentially parallel to the at least the first direction or essentially perpendicular to the at least the first direction.
1. A magnetic memory device comprising:
a magnetic element including a data storage layer having at least one easy axis in at least a first direction; and
a hard bias structure surrounding a portion of the magnetic element and configured to provide at least one hard bias field essentially parallel to the at least the first direction or essentially perpendicular to the at least the first direction.
2. The magnetic memory device of claim 1 further comprising:
an insulating layer sandwiched between the portion of the magnetic element and the hard bias structure.
3. The magnetic memory device of claim 1 wherein the hard bias field is configured to ensure that the data storage layer has a first equilibrium state.
4. The magnetic memory device of claim 1 wherein the magnetic element further includes a pinned layer and a spacer layer, the data storage layer being a free layer, the spacer layer residing between the pinned layer and the free layer.
5. The magnetic memory device of claim 4 wherein the spacer layer is conductive.
6. The magnetic memory device of claim 4 wherein the spacer layer is a tunneling barrier layer.
7. The magnetic memory device of claim 4 wherein the pinned layer is a synthetic pinned layer including at least a first ferromagnetic layer, a second ferromagnetic layer, and a conductive nonmagnetic spacer layer between the first ferromagnetic layer and the second ferromagnetic layer.
8. The magnetic memory device of claim 4 wherein the free layer is a synthetic free layer including at least a first ferromagnetic layer, a second ferromagnetic layer, and a conductive nonmagnetic spacer layer between the first ferromagnetic layer and the second ferromagnetic layer.
9. The magnetic memory device of claim 4 wherein the free layer has a top surface and the hard bias structure has a top surface, the top surface of hard bias structure residing higher than the top surface of free layer.
10. The magnetic memory device of claim 1 wherein the at least one hard bias field is essentially perpendicular to the at least the direction.
11. The magnetic memory device of claim 1 wherein the at least one hard bias field is essentially parallel to the at least the direction.
12. The magnetic memory device of claim 11 wherein the data storage layer is configured to be written using a toggle writing scheme.
13. The magnetic memory device of claim 1 wherein the hard bias field is substantially uniform across the data storage layer.
14. A magnetic memory comprising:
a plurality of magnetic elements, each of the plurality of magnetic elements including a data storage layer having at least one easy axis in at least a first direction; and
at least one hard bias structure surrounding a portion of each of the plurality of magnetic elements and configured to provide at least one hard bias field essentially parallel to the at least the first direction or essentially perpendicular to the at least the first direction.
15. The magnetic memory of claim 14 wherein each of the plurality of magnetic elements further includes an insulating layer sandwiched between the portion of the magnetic element and the hard bias structure.
16. The magnetic memory of claim 14 wherein the hard bias field is configured to ensure that the data storage layer has a first equilibrium state.
17. The magnetic memory of claim 14 wherein each of the plurality of magnetic elements further includes a pinned layer and a spacer layer, the data storage layer being a free layer, the spacer layer residing between the pinned layer and the free layer.
18. The magnetic memory of claim 17 wherein the spacer layer is conductive.
19. The magnetic memory of claim 17 wherein the spacer layer is a tunneling barrier layer.
20. The magnetic memory of claim 17 wherein the pinned layer is a synthetic pinned layer including at least a first ferromagnetic layer, a second ferromagnetic layer, and a conductive nonmagnetic spacer layer between the first ferromagnetic layer and the second ferromagnetic layer.
21. The magnetic memory of claim 17 wherein the free layer is a synthetic free layer including at least a first ferromagnetic layer, a second ferromagnetic layer, and a conductive nonmagnetic spacer layer between the first ferromagnetic layer and the second ferromagnetic layer.
22. The magnetic memory of claim 17 wherein the free layer has a top surface and the hard bias structure has a top surface, the top surface of the hard bias structure residing higher than the top surface of the free layer.
23. The magnetic memory of claim 14 wherein the at least one hard bias field is essentially perpendicular to the at least the direction.
24. The magnetic memory of claim 14 herein the at least one hard bias field is essentially parallel to the at least the direction.
25. The magnetic memory of claim 24 wherein the data storage layer is configured to be written using a toggle writing scheme.
26. The magnetic memory of claim 14 wherein the hard bias field is substantially uniform across the data storage layer.
27. A method for providing magnetic memory device comprising:
providing a magnetic element including a data storage layer having at least one easy axis in at least a first direction;
providing a hard bias structure surrounding a portion of the magnetic element and configured to provide at least one hard bias field essentially parallel to the at least the first direction or essentially perpendicular to the at least the first direction; and
setting the hard bias field to be essentially in the at least the first direction or essentially perpendicular to the at least the first direction.
28. The method of claim 27 further comprising:
providing an insulating layer sandwiched between the portion of the magnetic element and the hard bias structure.
29. The method of claim 27 wherein the data storage layer includes a free layer and wherein the pinned layer providing further includes:
providing a pinned layer; and
providing a spacer layer, the data storage layer being a free layer, the spacer layer residing between the pinned layer and the free layer.