Systems, articles, and methods related to multilayered magnetic memory devices
A magnetic memory device includes a magnetic track extending in a first direction. The magnetic track includes a lower magnetic layer, an upper magnetic layer on the lower magnetic layer, a non-magnetic pattern on the lower magnetic layer and at a side of the upper magnetic layer, and a spacer layer between the lower magnetic layer and the upper magnetic layer and extending between the lower magnetic layer and the non-magnetic pattern. The lower magnetic layer and the upper magnetic layer are antiferromagnetically coupled to each other by the spacer layer. The non-magnetic pattern has a first surface and a second surface which are opposite to each other in a second direction perpendicular to the first direction. A junction surface between the non-magnetic pattern and the upper magnetic layer is inclined with respect to a reference surface perpendicular to the first surface and the second surface.
1 . A magnetic memory device comprising:
a magnetic track extending in a first direction,
wherein the magnetic track comprises:
a lower magnetic layer;
an upper magnetic layer on the lower magnetic layer;
a non-magnetic pattern on the lower magnetic layer and at a side of the upper magnetic layer; and
a spacer layer between the lower magnetic layer and the upper magnetic layer and extending between the lower magnetic layer and the non-magnetic pattern,
wherein the lower magnetic layer and the upper magnetic layer are antiferromagnetically coupled to each other by the spacer layer,
wherein the non-magnetic pattern has a first surface and a second surface, which are opposite to each other in a second direction perpendicular to the first direction, and the first direction and the second direction are parallel to a plane, and
wherein a junction surface between the non-magnetic pattern and the upper magnetic layer is inclined with respect to a reference surface perpendicular to the first surface and the second surface of the non-magnetic pattern.
2 . The magnetic memory device of claim 1 , wherein an angle between the reference surface and the junction surface between the non-magnetic pattern and the upper magnetic layer is greater than 30 degrees.
3 . The magnetic memory device of claim 1 , wherein the lower magnetic layer comprises lower magnetic domains and lower magnetic domain walls, which are alternately arranged in the first direction,
wherein the upper magnetic layer comprises upper magnetic domains and upper magnetic domain walls, which are alternately arranged in the first direction, and
wherein the upper magnetic domains vertically overlap with the lower magnetic domains in a third direction perpendicular to the first direction and the second direction, respectively.
4 . The magnetic memory device of claim 3 , wherein the non-magnetic pattern vertically overlaps with a corresponding lower magnetic domain of the lower magnetic domains in the third direction.
5 . The magnetic memory device of claim 1 , wherein the non-magnetic pattern includes oxygen.
6 . The magnetic memory device of claim 1 , wherein the non-magnetic pattern includes a metal oxide.
7 . The magnetic memory device of claim 1 , wherein the non-magnetic pattern includes a same magnetic element as a magnetic element in the upper magnetic layer and further includes oxygen.
8 . The magnetic memory device of claim 1 , further comprising:
a conductive line under the magnetic track and extending in the first direction,
wherein the lower magnetic layer is between the conductive line and the spacer layer.
9 . The magnetic memory device of claim 8 , wherein the conductive line is configured to generate spin-orbit torque by a current flowing therein.
10 . The magnetic memory device of claim 8 , wherein the conductive line includes a heavy metal element.
11 . The magnetic memory device of claim 8 , further comprising:
a read/write unit on the magnetic track,
wherein the upper magnetic layer is between the read/write unit and the spacer layer.
12 . The magnetic memory device of claim 1 , wherein the non-magnetic pattern vertically overlaps with a portion of the lower magnetic layer in a third direction perpendicular to the first direction and the second direction,
wherein the magnetic track has a ferromagnet-synthetic antiferromagnet (FM-SAF) lateral junction structure in which a ferromagnetic region and a synthetic antiferromagnetic region are joined to each other in the first direction,
wherein the synthetic antiferromagnetic region is a region in which the lower magnetic layer and the upper magnetic layer are antiferromagnetically coupled to each other by the spacer layer, and
wherein the ferromagnetic region comprises: the non-magnetic pattern and the portion of the lower magnetic layer which vertically overlaps with the non-magnetic pattern.
13 . A magnetic memory device comprising:
a magnetic track extending in a first direction,
wherein the magnetic track comprises:
a lower magnetic layer;
an upper magnetic layer on the lower magnetic layer;
a non-magnetic pattern on the lower magnetic layer and at a side of the upper magnetic layer; and
a spacer layer between the lower magnetic layer and the upper magnetic layer and extending between the lower magnetic layer and the non-magnetic pattern,
wherein the lower magnetic layer and the upper magnetic layer are antiferromagnetically coupled to each other by the spacer layer,
wherein the non-magnetic pattern has a first surface and a second surface which are opposite to each other in a second direction perpendicular to the first direction, and the first direction and the second direction are parallel to a plane, and
wherein a length of the non-magnetic pattern in the first direction becomes progressively greater from the first surface toward the second surface.
14 . The magnetic memory device of claim 13 , wherein the non-magnetic pattern is in contact with a side surface of the upper magnetic layer.
15 . The magnetic memory device of claim 14 , wherein a junction surface between the non-magnetic pattern and the upper magnetic layer is inclined with respect to a reference surface perpendicular to the first surface and the second surface of the non-magnetic pattern.
16 . The magnetic memory device of claim 15 , wherein an angle between the reference surface and the junction surface between the non-magnetic pattern and the upper magnetic layer is greater than 30 degrees.
17 . The magnetic memory device of claim 13 , wherein the lower magnetic layer comprises lower magnetic domains and lower magnetic domain walls, which are alternately arranged in the first direction,
wherein the upper magnetic layer comprises upper magnetic domains and upper magnetic domain walls, which are alternately arranged in the first direction, and
wherein the upper magnetic domains vertically overlap with the lower magnetic domains in a third direction perpendicular to the first direction and the second direction, respectively.
18 . The magnetic memory device of claim 17 , wherein the non-magnetic pattern vertically overlaps with a corresponding lower magnetic domain of the lower magnetic domains in the third direction.
19 . The magnetic memory device of claim 13 , wherein the non-magnetic pattern includes a same magnetic element as a magnetic element in the upper magnetic layer and further includes oxygen.
20 . The magnetic memory device of claim 13 , further comprising:
a conductive line under the magnetic track and extending in the first direction,
wherein the conductive line is configured to generate spin-orbit torque by a current flowing therein.