Abstract: A memory device includes a vertical string of nonvolatile memory cells on a substrate, along with a ground selection transistor extending between the vertical string of nonvolatile memory cells and the substrate. The ground selection transistor can have a current carrying terminal electrically coupled to a channel region of a nonvolatile memory cell in the vertical string of nonvolatile memory cells. The ground selection transistor includes a gate electrode associated with a ground selection line of the memory device. This gate electrode includes: (i) a mask pattern, (ii) a barrier metal layer of a first material extending opposite a sidewall of the mask pattern and (iii) a metal pattern of a second material different from the first material extending between at least a portion of the barrier metal layer and the mask pattern.

Abstract: Disclosed is a semiconductor memory device including stacks on a substrate, a vertical channel portion connected to the substrate through each of the stacks, and a separation pattern disposed between the stacks. Each of the stacks may include a plurality of gate electrodes stacked on the substrate and insulating patterns interposed between the gate electrodes. Each of the gate electrodes may include a first metal pattern, which is disposed between the insulating patterns to define a recess region recessed toward the vertical channel portion, and a second metal pattern disposed in the recess region. The first and second metal patterns may contain the same metallic material and may have mean grain sizes different from each other.

Abstract: A method of manufacturing a semiconductor device includes forming an insulating pattern layer on a substrate, conformally forming a first conductive layer with a first thickness on the insulating pattern layer, wet etching the first conductive layer to have a second thickness that is less than the first thickness, and forming a second conductive layer on the first conductive layer after wet etching the first conductive layer. The second conductive layer includes a material that is different from a material included in the first conductive layer.

Abstract: A semiconductor device includes a first interlayer insulating layer and a second interlayer insulating layer, and a horizontal conductive pattern interposed between the first interlayer insulating layer and the second interlayer insulating layer. Vertical structures extend through the first interlayer insulating layer, the second interlayer insulating layer, and the horizontal conductive pattern. Each of the first interlayer insulating layer and the second interlayer insulating layer has regions of different impurity concentrations.

Abstract: A semiconductor device includes a first interlayer insulating layer and a second interlayer insulating layer, and a horizontal conductive pattern interposed between the first interlayer insulating layer and the second interlayer insulating layer. Vertical structures extend through the first interlayer insulating layer, the second interlayer insulating layer, and the horizontal conductive pattern. Each of the first interlayer insulating layer and the second interlayer insulating layer has regions of different impurity concentrations.

Abstract: Disclosed is a semiconductor memory device including stacks on a substrate, a vertical channel portion connected to the substrate through each of the stacks, and a separation pattern disposed between the stacks. Each of the stacks may include a plurality of gate electrodes stacked on the substrate and insulating patterns interposed between the gate electrodes. Each of the gate electrodes may include a first metal pattern, which is disposed between the insulating patterns to define a recess region recessed toward the vertical channel portion, and a second metal pattern disposed in the recess region. The first and second metal patterns may contain the same metallic material and may have mean grain sizes different from each other.

Abstract: A semiconductor device includes a lower structure including a lower conductor, an upper structure having an opening exposing the lower conductor on the lower structure, and a connection structure filling the opening and connected to the lower conductor. The connection structure includes a first tungsten layer covering an inner surface of the opening and defining a recess region in the opening, and a second tungsten layer filling the recess region on the first tungsten layer. A grain size of the second tungsten layer in an upper portion of the connection structure is greater than a grain size of the second tungsten layer in a lower portion of the connection structure.

Abstract: A semiconductor device includes a charge storage pattern on a substrate, a blocking insulating pattern on the charge storage pattern, and a control gate structure on the blocking insulating pattern, the control gate structure having a metal electrode pattern, and an oxidation prevention pattern on the metal electrode pattern, the oxidation prevention pattern including a metallic nitride.

Abstract: A memory device includes a gate structure, a contact plug, and a spacer. The gate structure includes first and second conductive layer patterns sequentially stacked on a substrate. The contact plug passes through the second conductive layer pattern, and a sidewall of the contact plug directly contacts at least a portion of the second conductive layer pattern. The spacer surrounds a portion of the sidewall of the contact plug and contacting the gate structure.

Abstract: A semiconductor device includes a lower insulating pattern on a semiconductor substrate, a lower gate pattern on the lower insulating pattern and formed of a doped polysilicon layer, a residual insulating pattern with an opening exposing a portion of a top surface of the lower gate pattern, an upper gate pattern on the residual insulating pattern, the upper gate pattern filling the opening, and a diffusion barrier pattern in contact with the portion of the top surface of the lower gate pattern and extending between the residual insulating pattern and the upper gate pattern.

Abstract: A semiconductor device includes a lower insulating pattern on a semiconductor substrate, a lower gate pattern on the lower insulating pattern and formed of a doped polysilicon layer, a residual insulating pattern with an opening exposing a portion of a top surface of the lower gate pattern, an upper gate pattern on the residual insulating pattern, the upper gate pattern filling the opening, and a diffusion barrier pattern in contact with the portion of the top surface of the lower gate pattern and extending between the residual insulating pattern and the upper gate pattern.

Abstract: A semiconductor device includes a lower insulating pattern on a semiconductor substrate, a lower gate pattern on the lower insulating pattern and formed of a doped polysilicon layer, a residual insulating pattern with an opening exposing a portion of a top surface of the lower gate pattern, an upper gate pattern on the residual insulating pattern, the upper gate pattern filling the opening, and a diffusion barrier pattern in contact with the portion of the top surface of the lower gate pattern and extending between the residual insulating pattern and the upper gate pattern.

Abstract: A semiconductor device includes a substrate including a conductive region, an insulating layer disposed on the substrate and including an opening exposing the conductive region, and a conductive layer buried within the opening and including a first region disposed on inner side walls of the opening and a second region disposed within the first region. The first region includes a plurality of first crystal grains and the second region includes a plurality of second crystal grains. The pluralities of first and second crystal grains are separated from each other at a boundary formed between the first and second regions.

Abstract: A semiconductor device includes a lower insulating pattern on a semiconductor substrate, a lower gate pattern on the lower insulating pattern and formed of a doped polysilicon layer, a residual insulating pattern with an opening exposing a portion of a top surface of the lower gate pattern, an upper gate pattern on the residual insulating pattern, the upper gate pattern filling the opening, and a diffusion barrier pattern in contact with the portion of the top surface of the lower gate pattern and extending between the residual insulating pattern and the upper gate pattern.

Abstract: A semiconductor device includes a lower insulating pattern on a semiconductor substrate, a lower gate pattern on the lower insulating pattern and formed of a doped polysilicon layer, a residual insulating pattern with an opening exposing a portion of a top surface of the lower gate pattern, an upper gate pattern on the residual insulating pattern, the upper gate pattern filling the opening, and a diffusion barrier pattern in contact with the portion of the top surface of the lower gate pattern and extending between the residual insulating pattern and the upper gate pattern.

Abstract: A semiconductor device includes a substrate, a first poly-silicon pattern on the substrate, a metal pattern on the first poly-silicon pattern, and an interface layer between the first poly-silicon pattern and the metal pattern. The interface layer may include at least one selected from the group of a metal-silicon oxynitride layer, a metal-silicon oxide layer, and a metal-silicon nitride layer.

Abstract: A memory device includes a gate structure, a contact plug, and a spacer. The gate structure includes first and second conductive layer patterns sequentially stacked on a substrate. The contact plug passes through the second conductive layer pattern, and a sidewall of the contact plug directly contacts at least a portion of the second conductive layer pattern. The spacer surrounds a portion of the sidewall of the contact plug and contacting the gate structure.

Abstract: Semiconductor devices and methods of fabricating semiconductor devices that may include forming an insulation structure including insulation patterns that are sequentially stacked and vertically separated from each other to provide gap regions between the insulation patterns, forming a first conductive layer filling the gap regions and covering two opposite sidewalls of the insulation structure, and forming a second conductive layer covering the first conductive layer. A thickness of the second conductive layer covering an upper sidewall of the insulation structure is greater than a thickness of the second conductive layer covering a lower sidewall of the insulation structure.

Abstract: A semiconductor device includes a lower insulating pattern on a semiconductor substrate, a lower gate pattern on the lower insulating pattern and formed of a doped polysilicon layer, a residual insulating pattern with an opening exposing a portion of a top surface of the lower gate pattern, an upper gate pattern on the residual insulating pattern, the upper gate pattern filling the opening, and a diffusion barrier pattern in contact with the portion of the top surface of the lower gate pattern and extending between the residual insulating pattern and the upper gate pattern.

Abstract: A semiconductor device may include a contact mold layer on a substrate, the contact mold layer defining first and second contact portions on the substrate, a wire mold layer on the contact mold layer, and first and second wires penetrating the wire mold layer and extending in a first direction, the first and second wires contacting the respective first and second contact portions and the contact mold layer. The first and second wires may be arranged in an alternating manner, and the first and second contact portions may be arranged to have a zigzag configuration. Each of the first and second contact portions may include a conductive pattern and a barrier pattern, and the barrier pattern may have a top surface lower than a top surface of the contact mold layer.