US 2020/0090723 A1Published application

Nonvolatile storage device

AssigneeToshiba Memory Corporation

InventorAkira KATAYAMA

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Abstract

A nonvolatile storage device includes a first wiring extending in a first direction, a second wiring extending in a second direction, a memory cell between the first and second wirings, a reading circuit configured to read data from the memory cell during a first and a second reading period, a writing circuit configured to write reference data into the memory cell during a writing period between the first and second reading periods, and a determination circuit configured to compare a first voltage which is based on the data read during the first reading period with a second voltage which is based on the data read during the second reading period, to determine the value of the data read during the first reading period. A current is caused to flow in the memory cell during the first reading period, the writing period, and the second reading period.

Claims20

Dependent claims

A nonvolatile storage device comprising:

a first wiring extending in a first direction;
a second wiring extending in a second direction that crosses the first direction;
a memory cell between the first wiring and the second wiring, the memory cell including a variable resistance storage element capable of being set to a low resistance state or a high resistance according to a value of data stored in the memory cell and a two-terminal switching element by which the variable resistance storage element is selected, wherein the variable resistance storage element and the two-terminal switching element are connected in series;
a reading circuit configured to read data from the memory cell during a first reading period and during a second reading period;
a writing circuit configured to write reference data into the memory cell during a writing period between the first reading period and the second reading period;
and
a determination circuit configured to compare a first voltage which is based on the data read during the first reading period with a second voltage which is based on the data read during the second reading period, to determine the value of the data read during the first reading period,
wherein a current is caused to flow in the memory cell in a same direction during the first reading period, during the writing period, and during the second reading period.

5 more elements

A nonvolatile storage device comprising:

a first wiring extending in a first direction;
a second wiring extending in a second direction that crosses the first direction;
a memory cell between the first wiring and the second wiring, the memory cell including a variable resistance storage element having a first end connected to the first wiring, and a switching element having a first end connected to a second end of the variable resistance storage element and a second end connected to the second wiring;
a reading circuit configured to charge at least one of a first capacitor and a second capacitor with a voltage corresponding to a value of data written into the memory cell;
a writing circuit configured to set the variable resistance storage element to a low resistance state or a high resistance state in accordance with a value of data to be written into the memory cell;
and
a control circuit configured to perform a read operation by controlling the reading circuit and the writing circuit to perform a first read operation, a write operation, and a second read operation in succession, wherein
during the first read operation, the write operation, and the second read operation, the control circuit causes current to continuously flow in the memory cell in a same direction.

5 more elements

Dependencies are inferred from the claim text.