Memory array decoding and interconnects
Methods and apparatuses for thin film transistors and related fabrication techniques are described. The thin film transistors may access two or more decks of memory cells disposed in a cross-point architecture. The fabrication techniques may use one or more patterns of vias formed at a top layer of a composite stack, which may facilitate building the thin film transistors within the composite stack while using a reduced number of processing steps. Different configurations of the thin film transistors may be built using the fabrication techniques by utilizing different groups of the vias. Further, circuits and components of a memory device (e.g., decoder circuitry, interconnects between aspects of one or more memory arrays) may be constructed using the thin film transistors as described herein along with related via-based fabrication techniques.
1. A method, comprising:
receiving an indication of an access operation for a memory cell;
identifying a first deck of memory cells that includes the memory cell, the first deck included in a plurality of decks;
coupling, based at least in part on the identifying and using a first transistor included in the first deck, a first electrode included in the first deck with a first conductive plug that extends through the plurality of decks, wherein the first transistor comprises a gate electrode and a semiconductor material at least partially surrounding the gate electrode; and
driving, based at least in part on coupling the first electrode with the first conductive plug and with the semiconductor material of the first transistor, the first electrode to a voltage associated with the access operation.
2. The method of claim 1 , further comprising:
coupling, based at least in part on the identifying and using a second transistor included in the first deck, a second electrode included in the first deck with a second conductive plug that extends through the plurality of decks; and
driving, based at least in part on coupling the second electrode with the second conductive plug, the second electrode to a second voltage associated with the access operation.
3. The method of claim 2 , further comprising:
coupling, based at least in part on the identifying and using a third transistor included in a second deck of the plurality of decks, the first electrode included in the first deck with the first conductive plug; and
coupling, based at least in part on the identifying and using a fourth transistor included in a third deck of the plurality of decks, the second electrode included in the first deck with the second conductive plug, wherein the first deck is between the second deck and the third deck.
4. The method of claim 3 , wherein driving the first electrode to the voltage associated with the access operation comprises:
activating the first transistor included in the first deck or the third transistor included in the second deck, or both.
5. The method of claim 1 , wherein the first electrode comprises an access line of a first type, further comprising:
coupling, based at least in part on the identifying and using transistors included in a subset of decks of the plurality of decks, access lines of the first type included in each deck of the subset with a third conductive plug that extends through the plurality of decks, wherein the subset excludes the first deck; and
driving, based at least in part on coupling the access lines of the first type included in each deck of the subset with the third conductive plug, the access lines of the first type included in each deck of the subset to a third voltage associated with the access operation.
6. The method of claim 5 , wherein a leakage current associated with the access lines of the first type during the access operation satisfies a threshold based at least in part on coupling the access lines of the first type included in each deck of the subset with the third conductive plug.
7. The method of claim 1 , wherein the first transistor comprises the semiconductor material at a first layer of the first deck and a second layer of the first deck, the semiconductor material surrounding the first conductive plug, an oxide material at the second layer of the first deck and in contact with the semiconductor material, the gate electrode at the second layer of the first deck and in contact with the oxide material, and an ohmic material at the first layer of the first deck and a third layer of the first deck, wherein the ohmic material at the first layer is in contact with the semiconductor material and with the first electrode, and wherein the ohmic material at the third layer is in contact with the first conductive plug.
8. The method of claim 1 , wherein the semiconductor material is coupled with the first electrode via a first segment of ohmic material at a first layer of the first deck and is coupled with the first conductive plug via a second segment of ohmic material at a third layer of the first deck.
9. An apparatus, comprising:
processing circuitry associated with one or more memory devices and configured to cause the apparatus to:
receive an indication of an access operation for a memory cell;
identify a first deck of memory cells that includes the memory cell, the first deck included in a plurality of decks;
couple, based at least in part on the identifying and using a first transistor included in the first deck, a first electrode included in the first deck with a first conductive plug that extends through the plurality of decks, wherein the first transistor comprises a gate electrode and a semiconductor material at least partially surrounding the gate electrode; and
drive, based at least in part on coupling the first electrode with the first conductive plug and with the semiconductor material of the first transistor, the first electrode to a voltage associated with the access operation.
10. The apparatus of claim 9 , wherein the processing circuitry is further configured to cause the apparatus to:
couple, based at least in part on the identifying and using a second transistor included in the first deck, a second electrode included in the first deck with a second conductive plug that extends through the plurality of decks; and
drive, based at least in part on coupling the second electrode with the second conductive plug, the second electrode to a second voltage associated with the access operation.
11. The apparatus of claim 10 , wherein the processing circuitry is further configured to cause the apparatus to:
couple, based at least in part on the identifying and using a third transistor included in a second deck of the plurality of decks, the first electrode included in the first deck with the first conductive plug; and
couple, based at least in part on the identifying and using a fourth transistor included in a third deck of the plurality of decks, the second electrode included in the first deck with the second conductive plug, wherein the first deck is between the second deck and the third deck.
12. The apparatus of claim 11 , wherein, to drive the first electrode to the voltage associated with the access operation, the processing circuitry is further configured to cause the apparatus to:
activate the first transistor included in the first deck or the third transistor included in the second deck, or both.
13. The apparatus of claim 9 , wherein the first electrode comprises an access line of a first type, wherein the processing circuitry is further configured to cause the apparatus to:
couple, based at least in part on the identifying and using transistors included in a subset of decks of the plurality of decks, access lines of the first type included in each deck of the subset with a third conductive plug that extends through the plurality of decks, wherein the subset excludes the first deck; and
drive, based at least in part on coupling the access lines of the first type included in each deck of the subset with the third conductive plug, the access lines of the first type included in each deck of the subset to a third voltage associated with the access operation.
14. The apparatus of claim 13 , wherein a leakage current associated with the access lines of the first type during the access operation satisfies a threshold based at least in part on coupling the access lines of the first type included in each deck of the subset with the third conductive plug.
15. The apparatus of claim 9 , wherein the first transistor comprises the semiconductor material at a first layer of the first deck and a second layer of the first deck, the semiconductor material surrounding the first conductive plug, an oxide material at the second layer of the first deck and in contact with the semiconductor material, the gate electrode at the second layer of the first deck and in contact with the oxide material, and an ohmic material at the first layer of the first deck and a third layer of the first deck, the ohmic material at the first layer is in contact with the semiconductor material and with the first electrode, and the ohmic material at the third layer is in contact with the first conductive plug.
16. The apparatus of claim 9 , wherein the semiconductor material coupled with the first electrode via a first segment of ohmic material at a first layer of the first deck and coupled with the first conductive plug via a second segment of ohmic material at a third layer of the first deck.
17. A non-transitory computer-readable medium storing code, the code comprising instructions executable by one or more processors to:
receive an indication of an access operation for a memory cell;
identify a first deck of memory cells that includes the memory cell, the first deck included in a plurality of decks;
couple, based at least in part on the identifying and using a first transistor included in the first deck, a first electrode included in the first deck with a first conductive plug that extends through the plurality of decks, wherein the first transistor comprises a gate electrode and a semiconductor material at least partially surrounding the gate electrode; and
drive, based at least in part on coupling the first electrode with the first conductive plug and with the semiconductor material of the first transistor, the first electrode to a voltage associated with the access operation.
18. The non-transitory computer-readable medium of claim 17 , wherein the instructions are further executable by the one or more processors to:
couple, based at least in part on the identifying and using a second transistor included in the first deck, a second electrode included in the first deck with a second conductive plug that extends through the plurality of decks; and
drive, based at least in part on coupling the second electrode with the second conductive plug, the second electrode to a second voltage associated with the access operation.
19. The non-transitory computer-readable medium of claim 18 , wherein the instructions are further executable by the one or more processors to:
couple, based at least in part on the identifying and using a third transistor included in a second deck of the plurality of decks, the first electrode included in the first deck with the first conductive plug; and
couple, based at least in part on the identifying and using a fourth transistor included in a third deck of the plurality of decks, the second electrode included in the first deck with the second conductive plug, wherein the first deck is between the second deck and the third deck.
20. The non-transitory computer-readable medium of claim 19 , wherein, to drive the first electrode to the voltage associated with the access operation, the instructions are further executable by the one or more processors to:
activate the first transistor included in the first deck or the third transistor included in the second deck, or both.