A vertical memory device includes gate electrodes on a substrate, a channel extending through the gate electrodes, and a contact plug extending through the gate electrodes. The gate electrodes are stacked in a first direction substantially vertical to an upper surface of the substrate and arranged to have a staircase shape including steps of which extension lengths in a second direction substantially parallel to the upper surface gradually increase from a lowermost level toward an uppermost level. A pad at an end portion of each of the gate electrodes in the second direction has a thickness greater than those of other portions thereof. The channel extends in the first direction. The contact plug extends in the first direction. The channel contacts the pad of a first gate electrode among the gate electrodes to be electrically connected thereto, and is electrically insulated from second gate electrodes among the gate electrodes.

Embodiments of 3D memory devices having staircase structures and methods for forming the same are disclosed. In an example, a 3D memory device includes a memory array structure and a staircase structure in an intermediate of the memory array structure and laterally dividing the memory array structure into a first memory array structure and a second memory array structure. The staircase structure includes a first staircase zone and a bridge structure connecting the first memory array structure and the second memory array structure. The first staircase zone includes a first pair of staircases facing each other in a first lateral direction and at different depths. Each staircase includes a plurality of stairs. At least one stair in the first pair of staircases is electrically connected to at least one of the first memory array structure and the second memory array structure through the bridge structure.

In certain aspects, a three-dimensional (3D) memory device includes a memory stack including interleaved conductive layers and dielectric layers, a plurality of channel structures each extending vertically through the memory stack, a conductive layer in contact with source ends of the plurality of channel structures, a first source contact electrically connected to the channel structures, and a second source contact electrically connected to the channel structures.

A nonvolatile memory device includes a cell array formed on a substrate, and a control gate pickup structure, wherein the cell array comprises floating gates, and a control gate surrounding the floating gates, wherein the control gate pickup structure comprises a floating gate polysilicon layer, a control gate polysilicon layer surrounding the floating gate polysilicon layer and connected to the control gate, and at least one contact plug formed on the control gate polysilicon layer.

A semiconductor device includes a substrate having cell array and extension regions, a gate electrode structure having gate electrodes stacked in a first direction, a channel through the gate electrode structure on the cell array region, a first division pattern extending in the second direction on the cell array and extension regions, the first division pattern being at opposite sides of the gate electrode structure in a third direction, an insulation pattern structure partially through the gate electrode structure on the extension region, a through via through the insulation pattern structure, and a support layer on the gate electrode structure and extending on the cell array and extension regions, the support layer contacting an upper sidewall of the first division pattern, and the support layer not contacting an upper surface of a portion of the first division pattern on the extension region adjacent to the insulation pattern structure.

A semiconductor device includes a substrate having cell array and extension regions, a gate electrode structure having gate electrodes stacked in a first direction, a channel through the gate electrode structure on the cell array region, a first division pattern extending in the second direction on the cell array and extension regions, the first division pattern being at opposite sides of the gate electrode structure in a third direction, an insulation pattern structure partially through the gate electrode structure on the extension region, a through via through the insulation pattern structure, and a support layer on the gate electrode structure and extending on the cell array and extension regions, the support layer contacting an upper sidewall of the first division pattern, and the support layer not contacting an upper surface of a portion of the first division pattern on the extension region adjacent to the insulation pattern structure.

Various methods overcome the limitations and achieve superior scaling by (i) replacing a single highly challenging high aspect ratio etch step with two or more etch steps of less challenging aspect ratios and which involve wider and more mechanically stable active strips, (ii) using dielectric pillars for support and to maintain structural stability during a high aspect ratio etch step and subsequent processing steps, or (iii) using multiple masking steps to provide two or more etch steps of less challenging aspect ratios and which involve wider and more mechanically stable active strips.

Some embodiments include a memory device and methods of forming the memory device. One such memory device includes a first group of memory cells, each of the memory cells of the first group being formed in a cavity of a first control gate located in one device level of the memory device. The memory device also includes a second group of memory cells, each of the memory cells of the second group being formed in a cavity of a second control gate located in another device level of the memory device. Additional apparatus and methods are described.

Some embodiments include a memory device and methods of forming the memory device. One such memory device includes a first group of memory cells, each of the memory cells of the first group being formed in a cavity of a first control gate located in one device level of the memory device. The memory device also includes a second group of memory cells, each of the memory cells of the second group being formed in a cavity of a second control gate located in another device level of the memory device. Additional apparatus and methods are described.

A semiconductor memory device according to an embodiment includes a memory cell array and a contact unit. The contact unit connects the memory cell array to a conductive layer and a contact. The contact unit includes a descending unit and an ascending unit. The descending unit includes a plurality of terrace parts descending in a first direction away from the memory cell array. The ascending unit is adjacent to the descending unit in a second direction perpendicular to the first direction. The ascending unit includes a plurality of terrace parts ascending in the first direction. The contact arranged in the terrace part of the descending unit and the contact arranged in the terrace part of the ascending unit are arranged in the second direction.