Spin-orbit torque magnetoresistance effect element and magnetic memory
A spin-orbit torque magnetoresistance effect element according to the present embodiment includes an element part including a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic layer positioned between the first ferromagnetic layer and the second ferromagnetic layer, a spin-orbit torque wiring positioned in a first direction with respect to the element part, facing the first ferromagnetic layer of the element part, and extending in a second direction, a first conductive part and a second conductive part facing the spin-orbit torque wiring at positions sandwiching the element part when viewed from the first direction, and a gate part positioned between the first conductive part and the second conductive part when viewed from the first direction, facing a second surface of the spin-orbit torque wiring on a side opposite to a first surface which faces the element part, and including a gate insulating layer and a gate electrode in order from a position near the spin-orbit torque wiring, in which the spin-orbit torque wiring includes a semiconductor to which a scattering element is added.
1. A spin-orbit torque magnetoresistance effect element comprising:
an element part including a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic layer positioned between the first ferromagnetic layer and the second ferromagnetic layer;
a spin-orbit torque wiring positioned in a first direction with respect to the element part, facing the first ferromagnetic layer of the element part, and extending in a second direction, the spin-orbit torque wiring including:
a semiconductor; and
a first surface which faces the element part and a second surface opposite to the first surface;
a first conductive part and a second conductive part facing the spin-orbit torque wiring at positions sandwiching the element part when viewed from the first direction, the first conductive part and the second conductive part facing the first surface or the second surface; and
a gate part positioned between the first conductive part and the second conductive part when viewed from the first direction, the gate part facing the second surface and including, in order from a position near the spin-orbit torque wiring:
a gate insulating layer that covers at least a part of the second surface of the spin-orbit torque wiring and covers both a part of the first conductive part and a part of the second conductive part; and
a gate electrode, the gate insulating layer occupying a larger area than the gate electrode when viewed from the first direction.
2. The spin-orbit torque magnetoresistance effect element according to claim 1 , further comprising:
a via wiring connected to the second ferromagnetic layer of the element part and extending in the first direction; and
a first transistor electrically connected to the element part by the via wiring.
3. The spin-orbit torque magnetoresistance effect element according to claim 1 , wherein the semiconductor constituting the spin-orbit torque wiring is any one selected from the group consisting of Si, SiGe, GaAs, Ge, and InGaAs.
4. The spin-orbit torque magnetoresistance effect element according to claim 1 , wherein the spin-orbit torque wiring contains a scattering element.
5. The spin-orbit torque magnetoresistance effect element according to claim 4 , wherein the scattering element is a heavy metal element having an atomic number equal to or higher than that of yttrium.
6. The spin-orbit torque magnetoresistance effect element according to claim 4 , wherein the scattering element is a magnetic element.
7. A magnetic memory comprising a plurality of spin-orbit torque magnetoresistance effect elements according to claim 1 .
8. The magnetic memory according to claim 7 , wherein
the plurality of spin-orbit torque magnetoresistance effect elements includes a first element row in which the spin-orbit torque magnetoresistance effect elements are disposed in the second direction, and
two spin-orbit torque magnetoresistance effect elements adjacent to each other in the second direction share the second conductive part of one spin-orbit torque magnetoresistance effect element as the first conductive part of the other spin-orbit torque magnetoresistance effect element in the first element row.
9. The magnetic memory according to claim 7 , wherein
the plurality of spin-orbit torque magnetoresistance effect elements includes a first element row in which the spin-orbit torque magnetoresistance effect elements are disposed in the second direction, and
spin-orbit torque wirings of the plurality of spin-orbit torque magnetoresistance effect elements constituting the first element row are connected to each other.
10. The magnetic memory according to claim 8 , wherein
the plurality of spin-orbit torque magnetoresistance effect elements further includes a second element row in which the spin-orbit torque magnetoresistance effect elements are disposed in a third direction different from the first direction and the second direction,
first conductive parts of the plurality of spin-orbit torque magnetoresistance effect elements constituting the second element row are connected to each other, and
second conductive parts of the plurality of spin-orbit torque magnetoresistance effect elements constituting the second element row are connected to each other.
11. The spin-orbit torque magnetoresistance effect element according to claim 1 , wherein in the second direction, a width of the gate part is larger than a width of the element part.
12. The spin-orbit torque magnetoresistance effect element according to claim 4 , wherein an amount of the scattering element is 1×10 13 cm −3 or more and 1×10 18 cm −3 or less.