Techniques for parallel memory cell access
Methods, systems, and devices for techniques for parallel memory cell access are described. A memory device may include multiple tiers of memory cells. During a first duration, a first voltage may be applied to a set of word lines coupled with a tier of memory cells to threshold one or more memory cells included in a first subset of memory cells of the tier. During a second duration, a second voltage may be applied to the set of word lines to write a first logic state to the one or more memory cells of the first subset and to threshold one or more memory cells included in a second subset of memory cells of the tier. During a third duration, a third voltage may be applied to the set of word lines to write a second logic state to the one or more memory cells of the second subset.
1 . A memory system, comprising:
a plurality of pillars extending vertically through a plurality of tiers of memory cells, each pillar of the plurality of pillars coupled with two memory cells at each tier of the plurality of tiers;
a plurality of bit lines;
a plurality of sets of pillar selectors, each set of pillar selectors associated with a respective conductive line configured to control activation of the set of pillar selectors, wherein a set of pillar selectors is configured to couple a subset of pillars of the plurality of pillars with the plurality of bit lines based at least in part on being activated;
a plurality of sets of word lines, each tier of memory cells coupled with multiple sets of word lines of the plurality of sets of word lines; and
one or more controllers coupled with the plurality of bit lines, the plurality of sets of pillar selectors, and the plurality of sets of word lines and operable to cause the memory system to apply a sequence of voltages to a first set of word lines of the plurality of sets of word lines coupled with a first tier of memory cells of the plurality of tiers of memory cells, wherein application of a first voltage of the sequence of voltages to the first set of word lines causes at least one memory cell of a first subset of the first tier of memory cells to be written to a first logic state and at least one memory cell of a second subset of the first tier of memory cells to threshold.
2 . The memory system of claim 1 , wherein, to apply the sequence of voltages to the first set of word lines, the one or more controllers are operable to cause the memory system to:
apply, during a first duration, a second voltage to the first set of word lines, the second voltage having a first polarity and a first magnitude;
apply, during a second duration, the first voltage to the first set of word lines, the first voltage having a second polarity different than the first polarity and having a second magnitude greater than the first magnitude; and
apply, during a third duration, a third voltage to the first set of word lines, the third voltage having the first polarity and a third magnitude greater than the first magnitude.
3 . The memory system of claim 2 , wherein the one or more controllers are further operable to cause the memory system to:
apply, during the first duration, a fourth voltage to a first subset of the plurality of bit lines, the fourth voltage having the second polarity different than the first polarity; and
determine a logic state of the at least one memory cell of the first subset of the first tier of memory cells based at least in part on applying the second voltage and the fourth voltage during the first duration.
4 . The memory system of claim 2 , wherein the one or more controllers are further operable to cause the memory system to:
adjust a threshold voltage of the at least one memory cell of the first subset of the first tier of memory cells based at least in part on applying the second voltage during the first duration.
5 . The memory system of claim 1 , wherein the one or more controllers are further operable to cause the memory system to:
apply a second sequence of voltages to a first subset of the plurality of bit lines, wherein the at least one memory cell of the first subset of the first tier of memory cells thresholds and is written to the first logic state based at least in part on applying the sequence of voltages and the second sequence of voltages; and
apply a third sequence of voltages to a second subset of the plurality of bit lines, wherein the at least one memory cell of the second subset of the first tier of memory cells thresholds and is written to a second logic state different than the first logic state based at least in part on applying the sequence of voltages and the third sequence of voltages.
6 . The memory system of claim 5 wherein, to apply the second sequence of voltages, the one or more controllers are operable to cause the memory system to:
apply, during a first duration, a second voltage to the first subset of the plurality of bit lines, the second voltage having a first polarity and a first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells stores the first logic state prior to the first duration; and
apply, during a second duration, a third voltage to the first subset of the plurality of bit lines, the third voltage having the first magnitude and a second polarity different than the first polarity, wherein the first logic state of the at least one memory cell of the first subset of the first tier of memory cells is refreshed based at least in part on applying the second voltage and the third voltage.
7 . The memory system of claim 5 wherein, to apply the second sequence of voltages, the one or more controllers are operable to cause the memory system to:
apply, during a first duration, a second voltage to the first subset of the plurality of bit lines, the second voltage having a first polarity and a first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells stores the second logic state prior to the first duration;
apply, during a second duration, a third voltage to the first subset of the plurality of bit lines, the third voltage having the first magnitude and a second polarity different than the first polarity; and
apply, during a third duration, a fourth voltage to the first subset of the plurality of bit lines, the fourth voltage having the first polarity and a second magnitude greater than the first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells is written to the first logic state based at least in part on applying the second voltage, the third voltage, and the fourth voltage.
8 . The memory system of claim 5 wherein, to apply the second sequence of voltages, the one or more controllers are operable to cause the memory system to:
apply, during a first duration, a second voltage to the first subset of the plurality of bit lines, the second voltage having a first polarity and a first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells stores the second logic state prior to the first duration; and
apply, during a second duration, a third voltage to the first subset of the plurality of bit lines, the third voltage having a second magnitude greater than the first magnitude and a second polarity different than the first polarity, wherein the at least one memory cell of the first subset of the first tier of memory cells is written to the first logic state based at least in part on applying the second voltage and the third voltage.
9 . The memory system of claim 5 wherein, to apply the second sequence of voltages, the one or more controllers are operable to cause the memory system to:
apply, during a first duration, a second voltage to the first subset of the plurality of bit lines, the second voltage having a first polarity and a first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells stores the first logic state prior to the first duration, and wherein the first logic state of the at least one memory cell of the first subset of the first tier of memory cells is refreshed based at least in part on applying the second voltage.
10 . A non-transitory computer-readable medium storing code, the code comprising instructions executable by one or more processors to:
apply a first sequence of voltages to a first set of word lines coupled with a first tier of memory cells of a plurality of tiers of memory cells, wherein each tier of the plurality of tiers is coupled with two sets of alternating word lines and a plurality of pillars extend vertically through the plurality of tiers, each pillar of the plurality of pillars coupled with a respective bit line of a plurality of bit lines and two memory cells at each tier of the plurality of tiers; and
apply one or more voltages to the plurality of bit lines,
wherein application of the one or more voltages to the plurality of bit lines and a first voltage of the first sequence of voltages to the first set of word lines causes at least one memory cell of a first subset of the first tier of memory cells to be written to a first logic state and at least one memory cell of a second subset of the first tier of memory cells to threshold.
11 . The non-transitory computer-readable medium of claim 10 , wherein the instructions to apply the first sequence of voltages to the first set of word lines are executable by the one or more processors to:
apply, during a first duration, a second voltage to the first set of word lines, the second voltage having a first polarity and a first magnitude;
apply, during a second duration, the first voltage to the first set of word lines, the first voltage having a second polarity different than the first polarity and having a second magnitude greater than the first magnitude; and
apply, during a third duration, a third voltage to the first set of word lines, the third voltage having the first polarity and a third magnitude greater than the first magnitude.
12 . The non-transitory computer-readable medium of claim 11 , wherein the instructions are further executable by the one or more processors to:
apply, during the first duration, a fourth voltage to a first subset of the plurality of bit lines, the fourth voltage having the second polarity different than the first polarity; and
determine a logic state of the at least one memory cell of the first subset of the first tier of memory cells based at least in part on applying the second voltage and the fourth voltage during the first duration.
13 . The non-transitory computer-readable medium of claim 11 , wherein the instructions are further executable by the one or more processors to:
adjust a first threshold voltage of the at least one memory cell of the first subset of the first tier of memory cells based at least in part on applying the second voltage during the first duration.
14 . The non-transitory computer-readable medium of claim 10 , wherein the instructions are further executable by the one or more processors to:
apply a second sequence of voltages to a first subset of the plurality of bit lines, wherein the at least one memory cell of the first subset of the first tier of memory cells thresholds and is written to the first logic state based at least in part on applying the first sequence of voltages and the second sequence of voltages; and
apply a third sequence of voltages to a second subset of the plurality of bit lines, wherein the at least one memory cell of the second subset of the first tier of memory cells thresholds and is written to a second logic state different than the first logic state based at least in part on applying the first sequence of voltages and the third sequence of voltages.
15 . The non-transitory computer-readable medium of claim 14 , wherein the instructions to apply the second sequence of voltages to the first subset of the plurality of bit lines are executable by the one or more processors to:
apply, during a first duration, a second voltage to the first subset of the plurality of bit lines, the second voltage having a first polarity and a first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells stores the first logic state prior to the first duration; and
apply, during a second duration, a third voltage to the first subset of the plurality of bit lines, the third voltage having the first magnitude and a second polarity different than the first polarity, wherein the first logic state of the at least one memory cell of the first subset of the first tier of memory cells is refreshed based at least in part on applying the second voltage and the third voltage.
16 . The non-transitory computer-readable medium of claim 14 wherein the instructions to apply the second sequence of voltages to the first subset of the plurality of bit lines are executable by the one or more processors to:
apply, during a first duration, a second voltage to the first subset of the plurality of bit lines, the second voltage having a first polarity and a first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells stores the second logic state prior to the first duration;
apply, during a second duration, a third voltage to the first subset of the plurality of bit lines, the third voltage having the first magnitude and a second polarity different than the first polarity; and
apply, during a third duration, a fourth voltage to the first subset of the plurality of bit lines, the fourth voltage having the first polarity and a second magnitude greater than the first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells is written to the first logic state based at least in part on applying the second voltage, the third voltage, and the fourth voltage.
17 . The non-transitory computer-readable medium of claim 14 wherein the instructions to apply the second sequence of voltages to the first subset of the plurality of bit lines are executable by the one or more processors to:
apply, during a first duration, a second voltage to the first subset of the plurality of bit lines, the second voltage having a first polarity and a first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells stores the second logic state prior to the first duration; and
apply, during a second duration, a third voltage to the first subset of the plurality of bit lines, the third voltage having a second magnitude greater than the first magnitude and a second polarity different than the first polarity, wherein the at least one memory cell of the first subset of the first tier of memory cells is written to the first logic state based at least in part on applying the second voltage and the third voltage.
18 . The non-transitory computer-readable medium of claim 14 wherein the instructions to apply the second sequence of voltages to the first subset of the plurality of bit lines are executable by the one or more processors to:
apply, during a first duration, a second voltage to the first subset of the plurality of bit lines, the second voltage having a first polarity and a first magnitude, wherein the at least one memory cell of the first subset of the first tier of memory cells stores the first logic state prior to the first duration, and wherein the first logic state of the at least one memory cell of the first subset of the first tier of memory cells is refreshed based at least in part on applying the second voltage.
19 . A method, comprising:
applying a sequence of voltages to a first set of word lines coupled with a first tier of memory cells of a plurality of tiers of memory cells, wherein each tier of the plurality of tiers is coupled with two sets of alternating word lines and a plurality of pillars extend vertically through the plurality of tiers, each pillar of the plurality of pillars coupled with a respective bit line of a plurality of bit lines and two memory cells at each tier of the plurality of tiers; and
applying one or more voltages to the plurality of bit lines,
wherein application of the one or more voltages to the plurality of bit lines and a first voltage of the sequence of voltages to the first set of word lines causes at least one memory cell of a first subset of the first tier of memory cells to be written to a first logic state and at least one memory cell of a second subset of the first tier of memory cells to threshold.
20 . The method of claim 19 , wherein applying the sequence of voltages to the first set of word lines comprises:
applying, during a first duration, a second voltage to the first set of word lines, the second voltage having a first polarity and a first magnitude;
applying, during a second duration, the first voltage to the first set of word lines, the first voltage having a second polarity different than the first polarity and having a second magnitude greater than the first magnitude; and
applying, during a third duration, a third voltage to the first set of word lines, the third voltage having the first polarity and a third magnitude greater than the first magnitude.