Memory device using spin hall effect and methods of manufacturing and operating the memory device
A memory device using a spin hall effect, and methods of manufacturing and operating the memory device, include applying a first operational current to a bit line of the memory device such that a spin current is applied to a magnetic tunnel junction (MTJ) cell coupled to the bit line due to a material in the bit line, wherein the bit line is electrically connected to a word line via the MTJ cell, and the word line intersects the bit line.
1. A memory device using a spin hall effect, comprising:
a bit line;
a word line intersecting the bit line; and
a magnetic tunnel junction (MTJ) cell between the word line and the bit line such that the MTJ cell is in a region where the bit line intersects the word line,
wherein the bit line includes a material layer configured to apply a spin current to the MTJ cell,
the bit line includes a first bit line layer on the MTJ cell, and a second bit line layer on the first bit line layer,
the first bit line layer includes a material having spin hall coupling, and
the second bit line layer includes a material layer having a specific resistance lower than a specific resistance of the material having spin hall coupling in the first bit line layer.
2. The memory device of claim 1 , wherein the MTJ cell includes a free layer having a horizontal magnetization direction.
3. The memory device of claim 1 , wherein the MTJ cell includes a free layer having a vertical magnetization direction.
4. A method of operating a memory device using a spin hall effect, comprising:
writing data in a magnetic tunnel junction (MTJ) cell of the memory device by,
applying a write current to a bit line of the memory device, and
generating a magnetic field around a word line of the memory device,
wherein the word line intersects the bit line,
the MTJ cell is between the word line and the bit line such that the MTJ cell is in a region where the bit line intersects the word line,
the bit line includes a material layer applying a spin current to the MTJ cell,
the bit line includes a first bit line layer on the MTJ cell, and a second bit line layer on the first bit line layer,
the applying the write current generates a spin current using a first material having spin hall coupling, the first material having spin hall coupling being in the first bit line layer, and
the second bit line layer includes a second material layer having a specific resistance lower than a specific resistance of the first material having spin hall coupling in the first bit line layer.
5. A method of operating a memory device using a spin hall effect, comprising:
reading data in the magnetic tunnel junction (MTJ) cell by,
forming a potential difference between a first bit line and a word line of the memory device,
measuring current passing through the MTJ cell, and
comparing the measured current and a reference value,
wherein the first bit line includes a first bit line layer on the MTJ cell, and a second bit line layer on the first bit line layer, the first bit line layer being a material layer applying a spin current to the MTJ cell,
the word line intersects the first bit line,
the MTJ cell is between the word line and the first bit line in a region where the first bit line intersects the word line,
the memory device further includes a plurality of bit lines, the plurality of bit lines including the first bit line, and
the first bit line contacts the MTJ cell.
6. The method of claim 5 ,
wherein, during the reading of data, the first bit line is selected, and remaining bit lines are in a floating state.
7. The method of claim 5 , further comprising:
a plurality of word lines maintaining equipotential during the reading of data.
8. A method of operating a memory device, comprising:
applying a first operational current to a bit line of the memory device such that a spin current is applied to a magnetic tunnel junction (MTJ) cell coupled to the bit line due to a material in the bit line,
wherein the bit line is electrically connected to a word line via the MTJ cell,
the word line intersects the bit line,
the bit line has a stack structure including a plurality of layers,
the material in the bit line is in a bottommost layer of the bit line,
writing data in the MTJ cell includes simultaneously applying the first operational current to the bit line and a second operational current to the word line,
the applying the second operational current results in the generation of a magnetic field, and
the MTJ cell is in an area of the magnetic field.
9. The method of claim 8 , wherein a free layer of the MTJ cell has a magnetization direction that is changeable by the magnetic field and the spin current.
10. The method of claim 8 , wherein the spin current is applied to the MTJ cell due to at least one property selected from a spin hall effect, a spin hole angle and spin orbit coupling of the material in the bit line.