Magnetic memory cells and semiconductor devices
View Patent ↗A magnetic cell includes a free region between an intermediate oxide region (e.g., a tunnel barrier) and a secondary oxide region. Both oxide regions may be configured to induce magnetic anisotropy (“MA”) with the free region, enhancing the MA strength of the free region. A getter material proximate to the secondary oxide region is formulated and configured to remove oxygen from the secondary oxide region, reducing an oxygen concentration and an electrical resistance of the secondary oxide region. Thus, the secondary oxide region contributes only minimally to the electrical resistance of the cell core. Embodiments of the present disclosure therefore enable a high effective magnetoresistance, low resistance area product, and low programming voltage along with the enhanced MA strength. Methods of fabrication, memory arrays, memory systems, and electronic systems are also disclosed.
1. A semiconductor device, comprising:
a magnetic region comprising a magnetic material exhibiting a switchable magnetic orientation;
an intermediate oxide region on a side of the magnetic region;
another oxide region on a side of the magnetic region opposite the intermediate oxide region; and
a getter material proximate to the another oxide region;
wherein the another oxide region exhibits an electrical resistance less than about 50% of an electrical resistance of the intermediate oxide region.
2. The semiconductor device of claim 1 , wherein the getter material comprises calcium, strontium, aluminum, barium, zirconium, compounds thereof, or combinations thereof.
3. The semiconductor device of claim 1 , wherein the getter material comprises a metal selected from the group consisting of calcium, strontium, aluminum, barium, and zirconium embedded in a carrier material.
4. The semiconductor device of claim 1 , wherein the getter material comprises oxygen diffused from the another oxide region.
5. The semiconductor device of claim 1 , wherein the intermediate oxide region and the another oxide region comprise the same elements.
6. The semiconductor device of claim 5 , wherein the another oxide region comprises a lower oxygen concentration than the intermediate oxide region.
7. The semiconductor device of claim 1 , wherein the another oxide region comprises a higher oxygen concentration proximate the magnetic region than proximate the getter material.
8. The semiconductor device of claim 1 , wherein the getter material comprises calcium or calcium carbonate.
9. An electronic system, comprising:
at least one processor coupled to system memory, the system memory comprising:
at least one semiconductor device, comprising:
a free region exhibiting a free magnetic orientation;
an intermediate oxide region adjacent to the free region;
a secondary oxide region adjacent to the free region and spaced from the intermediate oxide region by the free region, the secondary oxide region consisting of magnesium oxide; and
a getter material proximate to the secondary oxide region, the getter material consisting of oxygen and a metal selected from the group consisting of calcium, strontium, barium, and zirconium, wherein the getter material does not have a common interface with the free region.
10. The electronic device of claim 9 , wherein the secondary oxide region comprises an upper oxide sub-region and a lower oxide sub-region, the getter material located between the upper oxide sub-region and the lower oxide sub-region.
11. The electronic device of claim 9 , wherein the getter material substantially surrounds the secondary oxide region.
12. The electronic device of claim 9 , further comprising a fixed region on a side of the intermediate oxide region opposite the secondary oxide region.
13. The electronic device of claim 12 , wherein the fixed region comprises CoFeB.
14. The electronic device of claim 9 , wherein the secondary oxide region directly contacts the free region and the getter material.
15. The electronic device of claim 9 , wherein the getter material is closer to an underlying substrate than the secondary oxide region.
16. A semiconductor device, comprising:
a magnetic region having a switchable magnetic orientation;
another magnetic region having a fixed magnetic orientation;
an intermediate oxide region between the magnetic region and the another magnetic region;
a secondary oxide region directly contacting the magnetic region and spaced from the intermediate oxide region by the magnetic region, the secondary oxide region consisting of magnesium oxide and having a lower electrical resistance than the intermediate oxide region; and
a getter region proximate to the secondary oxide region, the getter region consisting of oxygen and a getter material selected from the group consisting of at least one of calcium, strontium, aluminum, barium, and zirconium, wherein the secondary oxide region has an electrical resistance of less than about 50% of an electrical resistance of the intermediate oxide region.
17. The semiconductor device of claim 16 , wherein the intermediate oxide region comprises magnesium oxide having a higher oxygen atomic percent than the secondary oxide region.
18. The semiconductor device of claim 16 , wherein the getter region consists of oxygen and calcium.
19. The semiconductor device of claim 16 , wherein the getter region is internal to the secondary oxide region.