Memory cells including vertically oriented adjustable resistance structures
View Patent ↗A memory cell is provided that includes a vertically-oriented adjustable resistance structure including a control terminal coupled to a word line, and a reversible resistance-switching element coupled in series with and disposed above or below the vertically-oriented adjustable resistance structure.
1. A memory cell comprising:
a vertically-oriented adjustable resistance structure comprising a control terminal coupled to a word line; and
a reversible resistance-switching element coupled in series with and disposed above or below the vertically-oriented adjustable resistance structure.
2. The memory cell of claim 1 , wherein the vertically-oriented adjustable resistance structure further comprises a vertically-oriented adjustable resistance material layer and a dielectric material layer disposed adjacent the control terminal.
3. The memory cell of claim 1 , wherein the vertically-oriented adjustable resistance structure further comprises a plurality of vertically-oriented adjustable resistance material layers and a dielectric material layer disposed adjacent the control terminal.
4. The memory cell of claim 1 , wherein the vertically-oriented adjustable resistance structure further comprises a vertically-oriented adjustable resistance material layer and a dielectric material layer disposed between the control terminal and the vertically-oriented adjustable resistance material layer.
5. The memory cell of claim 1 , wherein:
the vertically-oriented adjustable resistance structure comprises a vertically-oriented adjustable resistance material layer that comprises a semiconductor material; and
the vertically-oriented adjustable resistance material layer is fully depleted of majority charge carriers when a voltage is applied to the control terminal.
6. The memory cell of claim 1 , wherein the vertically-oriented adjustable resistance structure comprises a vertically-oriented adjustable resistance material layer that comprises any of intrinsic or undoped polycrystalline silicon, undoped silicon germanium, and indium gallium arsenide.
7. The memory cell of claim 1 , wherein the vertically-oriented adjustable resistance structure comprises:
a first terminal coupled via the reversible resistance-switching element to a bit line; and
a third terminal coupled to a common potential.
8. The memory cell of claim 1 , wherein the vertically-oriented adjustable resistance structure comprises:
a first terminal coupled to a bit line; and
a third terminal coupled via the reversible resistance-switching element to a common potential.
9. The memory cell of claim 1 , wherein the vertically-oriented adjustable resistance structure comprises:
a first terminal coupled via the reversible resistance-switching element to a bit line; and
a third terminal coupled to the control terminal.
10. The memory cell of claim 1 , wherein reversible resistance-switching element comprises any of a metal oxide, a solid electrolyte, a phase-change material, and a magnetic material.
11. The memory cell of claim 1 , wherein reversible resistance-switching element comprises any of NiO, Nb 2 O 5 , TiO 2 , HfO 2 , Al 2 O 3 , MgO x , CrO 2 , VO, BN, TaO 2 , Ta 2 O 3 , and MN.
12. A memory cell comprising:
a reversible resistance-switching element; and
a steering element coupled in series with and disposed above or below the reversible resistance-switching element, wherein the steering element comprises a vertically-oriented adjustable resistance structure comprising a control terminal coupled to a word line.
13. The memory cell of claim 12 , wherein the vertically-oriented adjustable resistance structure further comprises a vertically-oriented adjustable resistance material layer and a dielectric material layer disposed adjacent the control terminal.
14. The memory cell of claim 12 , wherein the vertically-oriented adjustable resistance structure further comprises a plurality of vertically-oriented adjustable resistance material layers and a dielectric material layer disposed adjacent the control terminal.
15. The memory cell of claim 12 , wherein the vertically-oriented adjustable resistance structure further comprises a vertically-oriented adjustable resistance material layer and a dielectric material layer disposed between the control terminal and the vertically-oriented adjustable resistance material layer.
16. The memory cell of claim 12 , wherein:
the vertically-oriented adjustable resistance structure comprises a vertically-oriented adjustable resistance material layer that comprises a semiconductor material; and
the vertically-oriented adjustable resistance material layer is fully depleted of majority charge carriers when a voltage is applied to the control terminal.
17. The memory cell of claim 12 , wherein the vertically-oriented adjustable resistance structure comprises a vertically-oriented adjustable resistance material layer that comprises any of intrinsic or undoped polycrystalline silicon, undoped silicon germanium, and indium gallium arsenide.
18. The memory cell of claim 12 , wherein the vertically-oriented adjustable resistance structure comprises:
a first terminal coupled via the reversible resistance-switching element to a bit line; and
a third terminal coupled to a common potential.
19. The memory cell of claim 12 , wherein the vertically-oriented adjustable resistance structure comprises:
a first terminal coupled to a bit line; and
a third terminal coupled via the reversible resistance-switching element to a common potential.
20. The memory cell of claim 12 , wherein reversible resistance-switching element comprises any of a metal oxide, a solid electrolyte, a phase-change material, and a magnetic material.
21. The memory cell of claim 12 , wherein reversible resistance-switching element comprises any of NiO, Nb 2 O 5 , TiO 2 , HfO 2 , Al 2 O 3 , MgO x , CrO 2 , VO, BN, TaO 2 , Ta 2 O 3 , and MN.
22. A method comprising:
providing a memory cell comprising:
a vertically-oriented adjustable resistance structure comprising a control terminal coupled to a word line; and
a reversible resistance-switching element coupled in series with and disposed above or below the vertically-oriented adjustable resistance structure;
applying a first voltage to the control terminal to set the vertically-oriented adjustable resistance structure to a first resistance; and
applying a second voltage to the control terminal to set the vertically-oriented adjustable resistance structure to a second resistance.
23. The method of claim 22 , wherein the first resistance is less than about 100 kΩ, and the second resistance is greater than about 10 MΩ.
24. The method of claim 22 , wherein:
the vertically-oriented adjustable resistance structure comprises a vertically-oriented adjustable resistance material layer comprising a semiconductor material; and
the method further comprises fully depleting the vertically-oriented adjustable resistance material layer of majority charge carriers.