Magnetic memory device
A magnetic memory device includes a first magnetic layer extending in a first direction, a pinned layer on the first magnetic layer, and a second magnetic layer vertically overlapping with the pinned layer with the first magnetic layer interposed between the pinned layer and the second magnetic layer. The first magnetic layer includes, a plurality of magnetic domains arranged in the first direction, and at least one magnetic domain wall between the plurality of magnetic domains, and a magnetization direction of the second magnetic layer is substantially parallel to a top surface of the first magnetic layer.
1. A magnetic memory device comprising:
a first magnetic layer extending in a first direction;
a pinned layer on the first magnetic layer; and
a second magnetic layer vertically overlapping with the pinned layer with the first magnetic layer interposed between the pinned layer and the second magnetic layer,
wherein the first magnetic layer includes, a plurality of magnetic domains arranged in the first direction, and at least one magnetic domain wall between the plurality of magnetic domains,
a magnetization direction of the second magnetic layer is substantially parallel to a top surface of the first magnetic layer, and
one or more electrodes are on a sidewall of the first magnetic layer.
2. The magnetic memory device of claim 1 , wherein the plurality of magnetic domains includes a first magnetic domain, a second magnetic domain, and a third magnetic domain, the first through third magnetic domains sequentially arranged in the first direction, and
a magnetization direction of the first magnetic domain and a magnetization direction of the third magnetic domain are anti-parallel to each other.
3. The magnetic memory device of claim 2 , wherein the second magnetic domain is configured to have a magnetization direction changeable to be parallel to a magnetization direction of the pinned layer or to be anti-parallel to the magnetization direction of the pinned layer.
4. The magnetic memory device of claim 1 , wherein the plurality of magnetic domains has a perpendicular magnetic anisotropy such that a magnetization direction of the plurality of the magnetic domains is perpendicular to a widest surface of the plurality of the magnetic domains.
5. The magnetic memory device of claim 1 , wherein the pinned layer has a perpendicular magnetic anisotropy such that a magnetization direction of the pinned layer is perpendicular to a widest surface of the pinned layer.
6. The magnetic memory device of claim 1 , further comprising:
a tunnel barrier pattern between the first magnetic layer and the pinned layer.
7. The magnetic memory device of claim 1 , further comprising:
an insulating layer between the first magnetic layer and the second magnetic layer.
8. The magnetic memory device of claim 1 , wherein the second magnetic layer has a synthetic anti-ferromagnetic (SAF) structure.
9. The magnetic memory device of claim 8 , wherein the synthetic anti-ferromagnetic (SAF) structure comprises:
a first magnetic pattern;
a second magnetic pattern; and
a spacer pattern between the first magnetic pattern and the second magnetic pattern.
10. The magnetic memory device of claim 9 , wherein a magnetization direction of the first magnetic pattern and a magnetization direction of the second magnetic pattern are anti-parallel to each other.
11. The magnetic memory device of claim 1 , wherein a length of the second magnetic layer in the first direction is less than or equal to a length of the first magnetic layer in the first direction.
12. The magnetic memory device of claim 1 , wherein a width of the second magnetic layer in a second direction, is substantially equal to a width of the first magnetic layer in the second direction, the second direction parallel to the top surface of the first magnetic layer and perpendicular to the first direction.
13. The magnetic memory device of claim 1 , wherein a thickness of the second magnetic layer in a third direction is substantially equal to a width of the second magnetic layer in a second direction, the third direction perpendicular to the top surface of the first magnetic layer and the second direction parallel to the top surface of the first magnetic layer and perpendicular to the first direction.
14. A magnetic memory device comprising:
a first magnetic layer extending in a first direction;
a pinned layer on the first magnetic layer; and
a second magnetic layer vertically overlapping with the pinned layer with the first magnetic layer interposed between the pinned layer and the second magnetic layer,
wherein the first magnetic layer includes a plurality of magnetic domains arranged in the first direction and at least one magnetic domain wall between the plurality of magnetic domains, and
a magnetization direction of the second magnetic layer is substantially perpendicular to magnetization directions of the magnetic domains, and
one or more electrodes are on a sidewall of the first magnetic layer.
15. The magnetic memory device of claim 14 , wherein the second magnetic layer has a synthetic anti-ferromagnetic (SAF) structure, and
the synthetic anti-ferromagnetic (SAF) structure comprises a first magnetic pattern, a second magnetic pattern, and a spacer pattern disposed between the first magnetic pattern and the second magnetic pattern.
16. The magnetic memory device of claim 14 , wherein the plurality of magnetic domains includes a first magnetic domain, a second magnetic domain, and a third magnetic domain, the first through third magnetic domains sequentially arranged in the first direction, and
a magnetization direction of the first magnetic domain and a magnetization direction of the third magnetic domain are anti-parallel to each other.
17. The magnetic memory device of claim 14 , further comprising:
a first electrode on the pinned layer;
a second electrode on one sidewall of the first magnetic layer; and
a third electrode on another sidewall of the first magnetic layer, the other sidewall opposite to the one sidewall of the first magnetic layer in the first direction.
18. A magnetic memory device comprising:
a first magnetic layer extending in a first direction;
a pinned layer on the first magnetic layer;
a tunnel barrier pattern between the first magnetic layer and the pinned layer;
a second magnetic layer vertically overlapping with the pinned layer with the first magnetic layer interposed between the pinned layer and the second magnetic layer; and
an insulating layer between the first magnetic layer and the second magnetic layer,
wherein the first magnetic layer includes a first magnetic domain, a second magnetic domain, and a third magnetic domain, the first through third magnetic domains sequentially arranged in the first direction,
a magnetization direction of the second magnetic layer is substantially parallel to a top surface of the first magnetic layer, and
a magnetization direction of the first magnetic domain and a magnetization direction of the third magnetic domain are anti-parallel to each other.
19. The magnetic memory device of claim 18 , wherein the insulating layer includes at least one of silicon oxide or silicon nitride.
20. The magnetic memory device of claim 18 , wherein the second magnetic domain includes a plurality of second magnetic domains, and
each of the second magnetic domains has a magnetization direction changeable to be parallel to a magnetization direction of the pinned layer or to be anti-parallel to the magnetization direction of the pinned layer.