Semiconductor memory device and control method thereof

Abstract

A semiconductor memory device of an embodiment includes a substrate, a first conductive layer provided above the substrate, the first conductive layer being spaced apart from the substrate in a first direction, and the first conductive layer being provided parallel to a substrate plane, a second conductive layer provided adjacent to the first conductive layer in a second direction intersecting the first direction, the second conductive layer being provided parallel to the substrate plane, a third conductive layer provided above the first conductive layer, the third conductive layer being spaced apart from the first conductive layer in the first direction, and the third conductive layer being provided parallel to the substrate plane, a fourth conductive layer provided above the second conductive layer, the fourth conductive layer being spaced apart from the second conductive layer in the first direction, and the fourth conductive layer being provided parallel to the substrate plane, a fifth conductive layer provided above the third conductive layer, the fifth conductive layer being spaced apart from the third conductive layer in the first direction, and the fifth conductive layer being provided parallel to the substrate plane, a sixth conductive layer provided above the fourth conductive layer, the sixth conductive layer being spaced apart from the fourth conductive layer in the first direction, and the sixth conductive layer being provided parallel to the substrate plane, an insulator provided between the first and second conductive layers, between the third and fourth conductive layers, and between the fifth and sixth conductive layers, a first signal line provided between the first, third, and fifth conductive layers and the insulator, the first signal line extending in the first direction, a second signal line provided between the second, fourth, and sixth conductive layers and the insulator, the second signal line extending in the first direction, a first memory cell provided between the first conductive layer and the first signal line, the first memory cell being configured to store first information, a second memory cell provided between the second conductive layer and the second signal line, the second memory cell being configured to store second information, a third memory cell provided between the third conductive layer and the first signal line, the third memory cell being configured to store third information, a fourth memory cell provided between the fourth conductive layer and the second signal line, the fourth memory cell being configured to store fourth information, a fifth memory cell provided between the fifth conductive layer and the first signal line, the fifth memory cell being configured to store fifth information, a sixth memory cell provided between the sixth conductive layer and the second signal line, the sixth memory cell being configured to store sixth information, and a control circuit configured to apply a second voltage to the third conductive layer, the control circuit being configured to apply a third voltage to the fifth conductive layer, the control circuit being configured to read data from the first memory cell, the second voltage being smaller than a first voltage, the first voltage being applied to the first conductive layer, and the third voltage being larger than the first voltage.