Thermally-assisted magnetic memory structures
View Patent ↗An exemplary thermally-assisted magnetic memory structure comprises a first conductor substantially surrounded by a cladding, a memory cell being thermally isolated from the first conductor by a thermally resistive region, and a second conductor electrically contacting the memory cell.
1. A thermally-assisted magnetic memory structure, comprising:
a first conductor substantially surrounded by a cladding;
a memory cell being thermally isolated from said first conductor by a thermally resistive region; and
a second conductor electrically contacting said memory cell.
2. The magnetic memory structure of claim 1 , wherein said thermally resistive region comprises air.
3. The magnetic memory structure of claim 1 , wherein said thermally resistive region forms a vacuum.
4. The magnetic memory structure of claim 1 , wherein said thermally resistive region comprises an insulator.
5. The magnetic memory structure of claim 1 , wherein said thermally resistive region is between said first conductor and said cladding.
6. The magnetic memory structure of claim 1 , wherein said memory cell contacts at least a portion of said cladding.
7. The magnetic memory structure of claim 1 , wherein said cladding comprises a material having a low thermal conductivity.
8. The magnetic memory structure of claim 1 , wherein said cladding comprises an amorphous metal alloy.
9. The magnetic memory structure of claim 1 , wherein said cladding comprises a ferromagnetic material.
10. The magnetic memory structure of claim 9 , wherein said cladding acts as a magnetic flux guide for magnetic fields generated by current flowing in said first conductor.
11. The magnetic memory structure of claim 10 , wherein said cladding width is selected to achieve a desired balance between: (1) non-saturation during write operations; and (2) minimum heat dissipation.
12. The magnetic memory structure of claim 1 , wherein said cladding substantially surrounds three sides of the first conductor.
13. The magnetic memory structure of claim 1 , wherein said memory cell comprises a ferromagnetic data layer, a spacer layer, and a ferromagnetic reference layer.
14. The magnetic memory structure of claim 1 , wherein said second conductor acts as a heater line to provide beat to said memory cell.
15. The magnetic memory structure of claim 1 , wherein said second conductor is a smaller heat sink than said first conductor.
16. A method for making a thermally-assisted magnetic memory structure, comprising:
forming a first conductor substantially surrounded by a cladding;
forming a second conductor; and
forming a memory cell, said memory cell:
electrically contacting said second conductor; and
being thermally isolated from said first conductor by a thermally resistive region.
17. The method of claim 16 , wherein said cladding comprises a material having a low thermal conductivity.
18. The method of claim 16 , wherein said cladding substantially surrounds three sides of said first conductor.
19. The method of claim 16 , further comprising:
forming a sacrificial layer above said first conductor and said cladding;
planarizing said sacrificial layer until a portion of said cladding is exposed;
forming an additional layer in said magnetic memory structure above said sacrificial layer; and
removing at least a portion of said sacrificial layer.
20. The method of claim 19 , wherein said sacrificial layer comprises a material having a different etching selectivity than at least one other layer in said magnetic memory structure.
21. The method of claim 19 , wherein said sacrificial layer comprises a polymer.
22. The method of claim 19 , wherein said sacrificial layer comprises a metal.
23. The method of claim 19 , wherein said sacrificial layer comprises an oxide.
24. The method of claim 16 , further comprising:
depositing a material on at least two sidewalls of said cladding until a portion of said material on said sidewalls meets and a thermally resistive region is encapsulated below said material; and
planarizing said material until a portion of said cladding is exposed.
25. The method of claim 24 , wherein said depositing comprises implementing a high angle of incidence deposition technique.
26. The method of 16 , wherein said memory cell contacts at least a portion of said cladding.
27. The method of claim 16 , further comprising:
forming an insulating layer between said thermally resistive region and said second conductor.
28. A nonvolatile memory array comprising a plurality of thermally-assisted magnetic memory structures, each of said magnetic memory structures being made by a process comprising:
forming a first conductor substantially surrounded by a cladding;
forming a second conductor; and
forming a memory cell, said memory cell:
electrically contacting said second conductor; and
being thermally isolated from said first conductor by a thermally resistive region.
29. A computer product comprising a microprocessor interfacing with an array of thermally-assisted magnetic memory structure, each of said thermally-assisted magnetic memory structure comprising:
a first conductor substantially surrounded by a cladding;
a memory cell being thermally isolated from said first conductor by a thermally resistive region; and
a second conductor electrically contacting said memory cell.