Magnetic memory device
View Patent ↗A magnetic memory device includes a magnetoresistive element and a first wiring layer. The magnetoresistive element includes a fixed layer, a recording layer, and a non-magnetic layer interposed therebetween. The first wiring layer extends in a first direction and generates a magnetic field for recording data in the magnetoresistive element. The recording layer includes a base portion extending in a second direction rotated from the first direction by an angle falling within a range of more than 0° to not more than 20°, and first and second projections projecting from the first and second sides of the base portion in a third direction perpendicular to the second direction. The third and fourth sides of the base portion are inclined with respect to the third direction in the same rotational direction as a rotational direction in which the second direction is rotated.
1. A magnetic memory device comprising:
a magnetoresistive element including a fixed layer having a direction of magnetization thereof fixed, a recording layer having a direction of magnetization thereof varied, and a non-magnetic layer interposed between the fixed layer and the recording layer; and
a first wiring layer extending in a first direction and configured to generate a magnetic field for recording data in the magnetoresistive element,
wherein the recording layer includes:
a base portion extending in a second direction rotated from the first direction by an angle falling within a range of more than 0° to not more than 20°, the base portion including a first side and a second side opposing each other and extending in the second direction, the base portion also including a third side and a fourth side opposing each other; and
a first projection and a second projection outwardly projecting from the first side and the second side, respectively, in a third direction perpendicular to the second direction, the third side-and the fourth side being inclined with respect to the third direction in the same rotational direction as a rotational direction in which the second direction is rotated.
2. The magnetic memory device according to claim 1 , wherein:
the second direction corresponds to an axis of easy magnetization; and
the third direction corresponds to an axis of hard magnetization.
3. The magnetic memory device according to claim 1 , wherein the third direction is inclined, by an angle falling within a range of more than 0° to not more than 20°, with respect to a fourth direction perpendicular to the first direction.
4. The magnetic memory device according to claim 1 , wherein the recording layer has a planar configuration which has 180° rotation symmetry and no reflection symmetry.
5. The magnetic memory device according to claim 1 , wherein the base portion has a rectangular planar configuration which includes a first pair of diagonally opposite two corners, and a second pair of diagonally opposite two corners, the first pair of corners having an acute angle, the second pair of corners having an obtuse angle.
6. The magnetic memory device according to claim 1 , wherein the base portion has a planar configuration of a parallelogram.
7. The magnetic memory device according to claim 1 , wherein a length of the recording layer in the second direction is longer than a length of the recording layer in the third direction.
8. The magnetic memory device according to claim 1 , wherein a length of the recording layer in the second direction is 1.5 times or more a length of the recording layer in the third direction.
9. The magnetic memory device according to claim 1 , wherein the recording layer has a plurality of round corners.
10. The magnetic memory device according to claim 1 , wherein the first projection has two round corners, and the second projection has two round corners.
11. The magnetic memory device according to claim 1 , wherein the base portion has four round corners.
12. The magnetic memory device according to claim 1 , wherein the angle falls within a range of more than 0° to not more than 15°.
13. The magnetic memory device according to claim 1 , wherein the angle falls within a range of more than 0° to not more than 5°.
14. The magnetic memory device according to claim 1 , further comprising a second wiring layer extending in a fourth direction perpendicular to the first direction and configured to generate a magnetic field for recording the data in the magnetoresistive element.
15. The magnetic memory device according to claim 1 , wherein the fixed layer includes a ferromagnetic layer and an anti-ferromagnetic layer.
16. The magnetic memory device according to claim 1 , further comprising:
a bit line extending in a fourth direction perpendicular to the first direction, and electrically connected to a terminal of the magnetoresistive element; and
a switching element having a terminal electrically connected to another terminal of the magnetoresistive element.
17. The magnetic memory device according to claim 16 , further comprising a word line configured to control an on-state and an off-state of the switching element.
18. The magnetic memory device according to claim 16 , further comprising a power supply connected to another terminal of the switching element.
19. The magnetic memory device according to claim 16 , wherein the switching element is an MIS (Metal Insulator Semiconductor) transistor.