Magnetic memory with porous non-conductive current confinement layer

1. A magnetic element comprising:

a ferromagnetic pinned layer having a pinned magnetization orientation, a ferromagnetic free layer having a changeable magnetization orientation, and a non-magnetic spacer layer therebetween; and

a porous non-electrically conducting current confinement layer between the ferromagnetic free layer and the ferromagnetic pinned layer, the porous non-electrically conducting current confinement layer present between the ferromagnetic free layer and the non-magnetic spacer layer and providing an interface between the ferromagnetic free layer and the non-magnetic spacer layer, or the porous non-electrically conducting current confinement layer present between the ferromagnetic pinned layer and the non-magnetic spacer layer and providing an interface between the ferromagnetic pinned layer and the non-magnetic spacer layer, with the porous non-electrically conducting current confinement layer having a thickness of 2 to 20 Angstroms, and comprising a non-electrically conducting material with a plurality of orderly arranged pores therein.

2. The magnetic element of claim 1 wherein the plurality of pores have a diameter of 2 to 200 Angstroms and are circular shaped.

3. The magnetic element of claim 1 wherein the porous non-electrically conducting current confinement layer comprises silica.

4. The magnetic element of claim 1 wherein the non-magnetic spacer layer is a tunnel barrier layer.

5. The magnetic element of claim 1 wherein the porous non-electrically conducting current confinement layer comprises a porous non-electrically conducting material comprising an insulating or dielectric material.

6. The magnetic element of claim 1 wherein the porous non-electrically conducting current confinement layer is present between the ferromagnetic free layer and the non-magnetic spacer layer.

7. The magnetic element of claim 1 wherein the pinned magnetization orientation and the changeable magnetization orientation are both out-of-plane.

8. The magnetic element of claim 1 wherein the porous non-electrically conducting current confinement layer comprises a plurality of islands of non-electrically conducting material.

9. The magnetic element of claim 8 wherein the plurality of islands have a diameter of 2 to 200 Angstroms and are dome shaped.

10. A magnetic element comprising:

a ferromagnetic pinned layer having a pinned magnetization orientation;

a non-magnetic spacer layer;

a ferromagnetic free layer having a changeable magnetization orientation;

a non-electrically conducting current confinement layer comprising non-electrically conducting material and areas devoid of non-electrically conducting material, the non-electrically conducting current confinement layer comprising a plurality of orderly arranged pores therein;

a first interface between the non-magnetic spacer layer and the non-electrically conducting current confinement layer;

a second interface either between the non-electrically conducting current confinement layer and the ferromagnetic free layer or between the non-electrically conducting current confinement layer and the ferromagnetic pinned layer; and

a third interface either between the non-magnetic spacer layer and the ferromagnetic free layer or between the non-magnetic spacer layer and the ferromagnetic pinned layer, present in areas devoid of non-electrically conducting material.

11. The magnetic element of claim 10 wherein the non-electrically conducting current confinement layer has a thickness of 2 to 20 Angstroms.

12. The magnetic element of claim 10 wherein the second interface is between the non-electrically conducting current confinement layer and the ferromagnetic free layer, and the third interface is between the non-magnetic spacer layer and the ferromagnetic free layer.

13. The magnetic element of claim 10 wherein the pinned magnetization orientation and the changeable magnetization orientation are both out-of-plane.

14. A method of making a spin torque magnetic element having a current confinement layer, the method comprising:

forming a ferromagnetic pinned layer and pinning a magnetic orientation of the pinned layer;

forming a non-magnetic spacer layer over the pinned layer;

forming a porous non-electrically conducting current confinement layer over and in contact with the non-magnetic spacer layer; and

forming a ferromagnetic free layer over the porous non-electrically conducting current confinement layer.

15. The method of claim 14 wherein forming a ferromagnetic free layer over the porous non-electrically conducting current confinement layer comprises:

filling a set of pores in the porous non-electrically conducting current confinement layer with a ferromagnetic free layer material.

16. The method of claim 14 wherein forming a porous non-electrically conducting current confinement layer over and in contact with the non-magnetic spacer comprises:

depositing droplets of dielectric or organic material over the non-magnetic spacer.

17. The method of claim 14 wherein forming a porous non-electrically conducting current confinement layer over and in contact with the non-magnetic spacer comprises:

coating a porous film of dielectric or organic material over the non-magnetic spacer.