Magnetic element having low saturation magnetization

1. A device comprising:

a magnetic element including:

a first fixed layer having a fixed layer magnetization;

a first free layer having a free layer magnetization that is changeable due to spin transfer when a write current above a threshold is passed through the first free layer, the first free layer including at least one ferromagnetic material and at least one nonmagnetic material, wherein the nonmagnetic material includes at least one of Zr, W, Ti, V or Hf;

a first spacer layer that is nonmagnetic, the first spacer layer residing between the first fixed layer and the first free layer; and

a high spin polarization layer residing between the first free layer and the first spacer layer wherein the high spin polarization layer has a higher spin polarization than the first free layer.

2. The device of claim 1 wherein the first free layer ferromagnetic material includes at least one of Co, Ni, or Fe.

3. The device of claim 1 wherein the first free layer ferromagnetic material includes at least one of alloy of CoNi, CoFe, NiFe, or CoNiFe.

4. The device of claim 1 wherein the first free layer includes at least five atomic percent and less than or equal to fifty atomic percent Zr, W, Ti, V, or Hf.

5. The device of claim 1 wherein the first spacer layer includes an insulating material.

6. The device of claim 5 wherein the insulating material includes Al 2 O 3 or MgO.

7. The device of claim 1 wherein the first spacer layer includes a conducting layer.

8. The device of claim 7 wherein the conducting layer includes at least one of Ru, Re, Cu, Ta or Cu, and an alloy that includes Ru, Re, Cu, Ta or Cu.

9. The device of claim 1 wherein the first fixed layer includes at least one ferromagnetic material and at least one nonmagnetic material;

wherein the nonmagnetic material includes at least one of Zr, W, Ti, V, or Hf.

10. The device of claim 1 wherein the first fixed layer is a first synthetic fixed layer.

11. The device of claim 1 wherein the first free layer is a first synthetic free layer.

12. The device of claim 1 comprising:

a plurality of magnetic elements.

13. The device of claim 1 comprising:

a conductor line;

a plurality of magnetic cells, each magnetic cell electrically connected to the conductor line to receive an electric current, each magnetic cell comprising a magnetic element; and

a circuit comprising a plurality isolation transistors, each isolation transistor electrically connected to a magnetic element inside a respective magnetic cell to control the electric current through the magnetic element.

14. A device comprising:

a magnetic element including:

a first fixed layer having a fixed layer magnetization;

a first spacer layer that is nonmagnetic;

a first free layer having a free layer magnetization that is changeable due to spin transfer when a write current above a threshold is passed through the free layer;

the first spacer layer residing between the first fixed layer and the first free layer, the first free layer including at least one ferromagnetic material and at least two nonmagnetic materials X and Y;

wherein the nonmagnetic material X includes at least one of Ti, Zr, or Hf; and

wherein the nonmagnetic material Y includes at least one of V, Nb, Ta, Cr, Mo, W, or Re.

15. The device of claim 14 wherein the first free layer ferromagnetic material includes at least one of Co, Ni, or Fe.

16. The device of claim 14 wherein the first free layer ferromagnetic material includes at least one of alloy of CoNi, CoFe, NiFe, or CoNiFe.

17. The device of claim 14 wherein the first free layer includes materials X and Y whose combined contents range from at least five atomic percent to less than or equal to fifty atomic percent.

18. The device of claim 17 wherein a ratio of the atomic percentages of the materials X and Y are controlled to achieve low magnetostriction.

19. The device of claim 14 wherein materials X and Y include Zr and Ta;

wherein the combined contents of Zr and Ta range from at least five atomic percent to less than or equal to fifty atomic percent;

wherein the atomic percentage of Zr is greater than the atomic percentage of Ta;

wherein the first free layer is in the hcp or fcc structure; and

wherein the first free layer has a perpendicular anisotropy.

20. The device of claim 14 wherein materials X and Y include Zr and Ta;

wherein the combined contents of Zr and Ta range from at least five atomic percent to less than or equal to fifty atomic percent;

wherein the atomic percentage of Zr is less than the atomic percentage of Ta; and

wherein the first free layer is in the bcc structure.

21. The device of claim 14 wherein the first spacer layer includes an insulating material.

22. The device of claim 21 wherein the insulating material includes Al 2 O 3 or MgO.

23. The device of claim 14 wherein the first spacer layer includes a conducting layer.

24. The device of claim 23 wherein the conducting layer includes at least one of Ru, Re, Cu, Ta and Cu, or an alloy that includes Ru, Re, Cu, Ta or Cu.

25. The device of claim 14 comprising:

a high spin polarization layer residing between the first free layer and the first spacer layer wherein the high spin polarization layer has a higher spin polarization than the first free layer.

26. The device of claim 14 wherein the first fixed layer includes at least one ferromagnetic material and at least two nonmagnetic materials X and Y; and

wherein the nonmagnetic material X includes at least one of Ti, Zr, or Hf and the nonmagnetic material Y includes at least one of V, Nb, Ta, Cr, Mo, W, or Re.

27. The device of claim 14 wherein the first fixed layer is a first synthetic fixed layer.

28. The device of claim 14 wherein the first free layer is a first synthetic free layer.

29. The device of claim 14 comprising:

a second spacer layer that is nonmagnetic; the first free layer residing between the second spacer layer and the first spacer layer and

a second fixed layer; the second spacer layer residing between the second fixed layer and the first free layer.

30. The device of claim 29 wherein the first spacer layer includes an insulating material and the second spacer layer includes an insulating material.

31. The device of claim 29 wherein the first spacer layer includes a conducting material and the second spacer layer includes an insulating material.

32. The device of claim 14 comprising:

a first separation layer; the first free layer residing between the first spacer layer and the first separation layer;

a second free layer having a free layer magnetization that is changeable due to the magnetic field created by the first free layer; the first separation layer residing between the first free layer and the second free layer;

a second spacer layer that is nonmagnetic; the second free layer residing between the second spacer layer and the first separation layer; and

a second fixed layer having a fixed layer magnetization; the second spacer layer residing between the second fixed layer and the second free layer.

33. The device of claim 14 comprising:

a plurality of magnetic elements.

34. The device of claim 14 comprising:

a conductor line;

a plurality of magnetic cells, each magnetic cell electrically connected to the conductor line to receive an electric current, each magnetic cell comprising a magnetic element; and

a circuit comprising a plurality isolation transistors, each isolation transistor electrically connected to a magnetic element inside a respective magnetic cell to control the electric current through the magnetic element.