A memory device that is as small in area as possible and has an extremely long data retention period. A transistor with extremely low leakage current is used as a cell transistor of a memory element in a memory device. Moreover, in order to reduce the area of a memory cell, the transistor is formed so that its source and drain are stacked in the vertical direction in a region where a bit line and a word line intersect each other. Further, a capacitor is stacked above the transistor.

According to an embodiment, a semiconductor memory device comprises control gate electrodes, a first semiconductor layer, a gate insulating layer, a first contact, a second semiconductor layer, a second contact, and a first conductive layer. The control gate electrodes are stacked above a substrate. The first semiconductor layer faces the control gate electrodes. The gate insulating layer is provided between the control gate electrode and the first semiconductor layer. The first contact is connected to an upper end of the first semiconductor layer. The second contact is connected to a lower end of the first semiconductor layer via the second semiconductor layer. The first conductive layer is provided above the second contact. Moreover, an end of the first conductive layer closest to the first contact is closer to the first contact than an end of the second contact closest to the first contact.

A semiconductor memory device according to an embodiment comprises: a plurality of control gate electrodes arranged in a first direction intersecting an upper surface of a substrate; a semiconductor layer extending in the first direction and facing a plurality of the control gate electrodes from a second direction intersecting the first direction; and a gate insulating layer provided between the control gate electrode and the semiconductor layer. The semiconductor layer comprises: a first portion extending in the first direction and facing a plurality of the control gate electrodes; and a second portion provided on a closer side to the substrate than this first portion. A film thickness of the first portion in the second direction is larger than a film thickness of the second portion in the second direction. A crystal grain included in the first portion is larger than a crystal grain included in the second portion.

A semiconductor memory device includes a stacked body including a first electrode layer and a second electrode layer stacked on the first electrode layer, and first and second interconnections on a first surface of the stacked body. The first and second electrode layers have first and second end surfaces respectively in the first surface. The first interconnection is electrically connected to the first electrode layer through a first region of the first end surface; and the second interconnection is electrically connected to the second electrode layer through a second region of the second end surface. The first and second interconnections extend in a first direction on the first surface. The first and second regions are arranged in a second direction crossing the first direction with a crossing angle smaller than 90 degrees. The first region and the second region each have a boundary along the second direction.

According to an embodiment, a semiconductor memory device comprises: control gate electrodes stacked above a substrate; a semiconductor layer that extends in a first direction above the substrate and faces the control gate electrodes; and a gate insulating layer provided between these control gate electrode and semiconductor layer. The gate insulating layer comprises: a first insulating layer covering a side surface of the semiconductor layer; a charge accumulation layer covering a side surface of this first insulating layer; and a second insulating layer including a metal oxide and covering a side surface of this charge accumulation layer. The charge accumulation layer has: a first portion facing the control gate electrode; and a second portion facing a region between control gate electrodes adjacent in the first direction and including more oxygen than the first portion.

Provided herein is a semiconductor device. The semiconductor device includes: a lower conductive pattern; a lower memory string conductive pattern disposed over the lower conductive pattern; a stack of upper memory string conductive patterns, wherein the stack is disposed over the lower memory string conductive pattern; a lower pad pattern extending from the lower memory string conductive pattern; upper pad patterns respectively extending from the upper memory string conductive patterns; a floating conductive pattern disposed under below the lower pad pattern, the floating conductive pattern overlapping the lower pad pattern; and a contact plug coming into contact with the lower pad pattern and overlapping the floating conductive pattern.

According to an embodiment, a semiconductor memory device comprises: a stacked body that includes a plurality of control gate electrodes stacked above a substrate; a memory columnar body that extends in a first direction above the substrate and configures a memory string along with the stacked body; and a source contact that extends in the first direction and is electrically connected to one end of the memory string. Moreover, this source contact is adjacent to the stacked body via a spacer insulating layer. Furthermore, a spacer protective layer including a nitride or a metal oxide is provided between these source contact and spacer insulating layer.

According to one embodiment, a semiconductor memory device includes a semiconductor layer, a plurality of conductive layers, a plurality of insulating layers, an intermediate layer, and a controller. The conductive layers and the insulating layers are alternately provided. The intermediate layer is provided between the plurality of conductive layers and the semiconductor layer. The controller is configured to perform first and second operations. In first operation, the controller applies a first voltage to the semiconductor layer, applies a second voltage higher than the first voltage to a first conductive layer, and applies a third voltage to other conductive layers. In the second operation, the controller applies a fourth voltage to the semiconductor layer, applies a fifth voltage to the first conductive layer, and applies a sixth voltage to the other conductive layers.

This nonvolatile semiconductor memory device includes: a memory cell array including a memory cell; a wiring part connecting the memory cell array to an external circuit; and a transistor that connects the wiring part and the external circuit, the transistor including: a first insulating layer including a first region, a second region, and a third region, the second and third regions being disposed on both sides of the first region, and a height of an upper surface of the first region being lower than those of the second region and the third region; a semiconductor layer disposed along upper surfaces of the first region, the second region, and the third region; and a gate electrode layer disposed via the semiconductor layer and a gate insulating film, on an upper part of the second region.

A semiconductor memory device according to an embodiment includes: a first semiconductor layer, a stacked body including a plurality of conductive layers and a plurality of interlayer insulating layers stacked in a first direction above the first semiconductor layer, a second semiconductor layer opposing the plurality of conductive layers, the second semiconductor layer has a longitudinal direction in the first direction, and a memory insulating layer including a charge accumulation layer and positioned between the second semiconductor layer and the plurality of conductive layers. A thickness in the first direction of at least a first conductive layer as one of the plurality of conductive layers is larger than a thickness in the first direction of another one of the plurality of conductive layers, and the first conductive layer is adjacent to the first semiconductor layer via one of the interlayer insulating layers.