Semiconductor memory device and operation method thereof
View Patent ↗A semiconductor memory device according to an embodiment includes a control circuit configured to apply a first voltage to a selected first line, apply a second voltage to a selected second line, and apply a third voltage and a fourth voltage to a non-selected first line and a non-selected second line in a setting operation, respectively. The control circuit includes a detection circuit configured to detect a transition of a resistance state of a selected memory cell using a reference voltage. The control circuit is configured to execute a read operation in which the control circuit applies the third voltage to the selected first line and the non-selected first line, applies the second voltage to the selected second line, and applies the fourth voltage to the non-selected second line, and set the reference voltage based on a voltage value of the selected second line.
1. A semiconductor memory device, comprising:
a memory cell array including,
a plurality of first lines disposed above a substrate,
a plurality of second lines disposed intersecting the first lines, and
variable resistance elements disposed at each of intersections of the first lines and the second lines; and
a control circuit configured to apply a first voltage to a selected first line, apply a second voltage having a voltage value which is smaller than that of the first voltage to a selected second line, and apply a third voltage and a fourth voltage to a non-selected first line and a non-selected second line in a setting operation, respectively, such that a first potential difference is applied to a selected variable resistance element disposed at the intersection of the selected first line and the selected second line,
the control circuit including a detection circuit configured to, during the setting operation, detect a transition of a resistance state of the selected variable resistance element using a reference voltage, and
the control circuit being configured to, before the setting operation, execute a read operation in which the control circuit applies the third voltage to the selected first line and the non-selected first line, applies the second voltage to the selected second line, and applies the fourth voltage to the non-selected second line, and set the reference voltage based on a voltage value of the selected second line during the read operation.
2. The semiconductor memory device according to claim 1 , wherein
the control circuit is configured to, when executing the setting operation on a plurality of the selected variable resistance elements, execute the read operation and the setting operation on each single one of the selected variable resistance elements.
3. The semiconductor memory device according to claim 1 , wherein
the control circuit is configured to, before the setting operation on a plurality of the selected variable resistance elements, detect voltage values of a plurality of the selected second lines by a plurality of times of the read operation.
4. The semiconductor memory device according to claim 1 , wherein
a plurality of the memory cell arrays are stacked in a direction perpendicular to the substrate.
5. The semiconductor memory device according to claim 1 , wherein
the variable resistance element changes from a high-resistance state to a low-resistance state by the first potential difference.
6. The semiconductor memory device according to claim 1 , wherein the third voltage and the fourth voltage are an identical voltage.
7. A method of operating a semiconductor memory device,
the semiconductor memory device comprising a memory cell array including a plurality of first lines disposed above a substrate, a plurality of second lines disposed intersecting the first lines, and variable resistance elements disposed at each of intersections of the first lines and the second lines and each configured having a variable resistance element, and
the semiconductor memory device configured to execute a setting operation in which a first voltage is applied to a selected first line, a second voltage having a voltage value which is smaller than that of the first voltage is applied to a selected second line, and a third voltage and a fourth voltage are applied to a non-selected first line and a non-selected second line, respectively, such that a first potential difference is applied to a selected variable resistance element disposed at the intersection of the selected first line and the selected second line,
the method comprising:
before the setting operation, executing a read operation in which the third voltage is applied to the selected first line and the non-selected first line, the second voltage is applied to the selected second line, and the fourth voltage is applied to the non-selected second line, and setting a reference voltage based on a voltage value of the selected second line during the read operation; and
during the setting operation, detecting a transition of a resistance state of the selected variable resistance element using the reference voltage.
8. The method of operating a semiconductor memory device according to claim 7 , wherein
when the setting operation is executed on a plurality of the selected variable resistance elements, the read operation and the setting operation are executed on each single one of the selected variable resistance elements.
9. The method of operating a semiconductor memory device according to claim 7 , wherein
before the setting operation on a plurality of the selected variable resistance elements, voltage values of a plurality of the selected second lines are detected by a plurality of times of the read operation.
10. The method of operating a semiconductor memory device according to claim 7 , wherein
the variable resistance element changes from a high-resistance state to a low-resistance state by the first potential difference.
11. The method of operating a semiconductor memory device according to claim 7 , wherein
the third voltage and the fourth voltage are an identical voltage.