Giant perpendicular magnetic anisotropy in Fe/GaN thin films for data storage and memory devices
A giant perpendicular magnetic anisotropy (PMA) material comprises a III-V nitride substrate, and a layer of nitrogen disposed upon a surface of the III-V nitride substrate. The layer of nitrogen forms an N-terminated surface. The PMA material further comprises an iron film disposed upon the N-terminated surface. The III-V nitride substrate may be gallium nitride (GaN). A memory device using the PMA material may further comprise an input/output interface configured to communicate an address signal, a read/write signal and a data signal. The memory device may further comprise a controller configured to coordinate reading data from and writing data to the memory element.
1. A giant perpendicular magnetic anisotropy (PMA) material, comprising:
a III-V nitride substrate;
a layer of nitrogen disposed upon a (000 1 ) surface of the III-V nitride substrate, the layer of nitrogen forming a (000 1 ) nitrogen terminated (N-terminated) surface; and
an iron film disposed upon the (000 1 ) N-terminated surface.
2. The giant PMA material of claim 1 , wherein the III-V nitride is gallium nitride (GaN).
3. The giant PMA material of claim 1 , wherein the layer of nitrogen is a wurtzite GaN (000 1 ) N-terminated surface.
4. The giant PMA material of claim 1 , wherein the layer of nitrogen is a monolayer of nitrogen atoms.
5. The giant PMA material of claim 1 , wherein the iron film is less than or equal to three monolayers of iron atoms.
6. A method of fabricating a giant PMA material, comprising:
exposing a (000 1 ) surface of a III-V nitride substrate to an atmosphere configured to provide a source of nitrogen, to dispose a layer of nitrogen on the (000 1 ) surface of the III-V nitride substrate, the layer of nitrogen forming an (000 1 ) N-terminated surface;
disposing an iron film upon the (000 1 ) N-terminated surface.
7. The method of claim 6 , wherein the atmosphere is configured to provide a source of nitrogen comprises an atmosphere of nitrogen.
8. The method of claim 6 , wherein the atmosphere is configured to provide a source of nitrogen comprising an atmosphere of excessive NH 3 .
9. The method of claim 8 , further comprising sample annealing the III-V nitride substrate in the atmosphere of excessive NH 3 .
10. The method of claim 6 , further comprising heating III-V nitride substrate to a temperature of 1000° C., while exposing the III-V nitride substrate to a nitrogen plasma.
11. The method of claim 10 , further comprising reducing the III-V nitride substrate to a temperature of 685° C., thereby initiating growth of the N-terminated surface.
12. The method of claim 6 , wherein the III-V nitride is gallium nitride (GaN).
13. The method of claim 6 , wherein the layer of nitrogen is a wurtzite GaN (000 1 ) N-terminated surface.
14. The method of claim 6 , wherein the layer of nitrogen is a monolayer of nitrogen atoms.
15. The method of claim 6 , wherein the iron film is less than or equal to three monolayers of iron atoms.
16. A memory device, comprising:
a memory element comprising:
a III-V nitride substrate;
a layer of nitrogen disposed upon a (000 1 ) surface of the III-V nitride substrate, the layer of nitrogen forming an (000 1 ) N-terminated surface; and
an iron film disposed upon the (000 1 ) N-terminated surface;
an input/output interface configured to communicate an address signal, a read/write signal and a data signal; and
a controller configured to coordinate reading data from and writing data to the memory element.
17. The memory device of claim 16 , wherein the III-V nitride is gallium nitride (GaN).
18. The memory device of claim 16 , wherein the layer of nitrogen is a wurtzite GaN (000 1 ) N-terminated surface.
19. The memory device of claim 16 , wherein the layer of nitrogen is a monolayer of nitrogen atoms.
20. The memory device of claim 16 , wherein the iron film is less than or equal to three monolayers of iron atoms.