Abstract: A semiconductor device including a substrate that includes first and second regions; a first active pattern on the first region, the first active pattern including first source/drain patterns and a first channel pattern between the first source/drain patterns; a second active pattern on the second region, the second active pattern including second source/drain patterns and a second channel pattern between the second source/drain patterns; and a first gate electrode on the first channel pattern and a second gate electrode on the second channel pattern, wherein a length of the first channel pattern is greater than a length of the second channel pattern, each of the first channel pattern and the second channel pattern includes a plurality of semiconductor patterns stacked on the substrate, and at least two semiconductor patterns of the first channel pattern are bent away from or toward a bottom surface of the substrate.

Abstract: Semiconductor devices include a first active pattern including a first lower pattern extending in a first direction and a first sheet pattern spaced apart from the first lower pattern; and a first gate electrode on the first lower pattern, the first gate electrode extending in a second direction and surrounding the first sheet pattern, wherein the first lower pattern includes a first sidewall and a second sidewall opposite to each other, each of the first sidewall of the first lower pattern and the second sidewall of the first lower pattern extends in the first direction, the first gate electrode overlaps the first sidewall of the first lower pattern in the second direction by a first depth, the first gate electrode overlaps the second sidewall of the first lower pattern in the second direction by a second depth, and the first depth is different from the second depth.

Abstract: Semiconductor devices include a first active pattern including a first lower pattern extending in a first direction and a first sheet pattern spaced apart from the first lower pattern; and a first gate electrode on the first lower pattern, the first gate electrode extending in a second direction different from the first direction and surrounding the first sheet pattern, wherein the first lower pattern includes a first sidewall and a second sidewall opposite to each other, each of the first sidewall of the first lower pattern and the second sidewall of the first lower pattern extends in the first direction, the first gate electrode overlaps the first sidewall of the first lower pattern in the second direction by a first depth, the first gate electrode overlaps the second sidewall of the first lower pattern in the second direction by a second depth, and the first depth is different from the second depth.

Abstract: Semiconductor devices include a first active pattern including a first lower pattern extending in a first direction and a first sheet pattern spaced apart from the first lower pattern; and a first gate electrode on the first lower pattern, the first gate electrode extending in a second direction different from the first direction and surrounding the first sheet pattern, wherein the first lower pattern includes a first sidewall and a second sidewall opposite to each other, each of the first sidewall of the first lower pattern and the second sidewall of the first lower pattern extends in the first direction, the first gate electrode overlaps the first sidewall of the first lower pattern in the second direction by a first depth, the first gate electrode overlaps the second sidewall of the first lower pattern in the second direction by a second depth, and the first depth is different from the second depth.

Abstract: Semiconductor devices include a first active pattern including a first lower pattern extending in a first direction and a first sheet pattern spaced apart from the first lower pattern; and a first gate electrode on the first lower pattern, the first gate electrode extending in a second direction different from the first direction and surrounding the first sheet pattern, wherein the first lower pattern includes a first sidewall and a second sidewall opposite to each other, each of the first sidewall of the first lower pattern and the second sidewall of the first lower pattern extends in the first direction, the first gate electrode overlaps the first sidewall of the first lower pattern in the second direction by a first depth, the first gate electrode overlaps the second sidewall of the first lower pattern in the second direction by a second depth, and the first depth is different from the second depth.

Abstract: A semiconductor device includes a first active pattern on a substrate, a pair of first source/drain patterns on the first active pattern and a first channel pattern between the pair of first source/drain patterns, wherein the first channel pattern includes a plurality of semiconductor patterns that are stacked and spaced apart from each other, a first gate electrode on the first channel pattern, a first gate cutting pattern that is adjacent to the first channel pattern and penetrates the first gate electrode, and a first residual pattern between the first gate cutting pattern and the first channel pattern. The first residual pattern covers an outermost sidewall of at least one semiconductor pattern of the plurality of semiconductor patterns of the first channel pattern. The first gate electrode includes, on an upper portion of the first gate electrode, a first extension that vertically overlaps the first residual pattern.

Abstract: A semiconductor device including a substrate that includes first and second regions; a first active pattern on the first region, the first active pattern including first source/drain patterns and a first channel pattern between the first source/drain patterns; a second active pattern on the second region, the second active pattern including second source/drain patterns and a second channel pattern between the second source/drain patterns; and a first gate electrode on the first channel pattern and a second gate electrode on the second channel pattern, wherein a length of the first channel pattern is greater than a length of the second channel pattern, each of the first channel pattern and the second channel pattern includes a plurality of semiconductor patterns stacked on the substrate, and at least two semiconductor patterns of the first channel pattern are bent away from or toward a bottom surface of the substrate.

Abstract: Semiconductor devices include a first active pattern including a first lower pattern extending in a first direction and a first sheet pattern spaced apart from the first lower pattern; and a first gate electrode on the first lower pattern, the first gate electrode extending in a second direction different from the first direction and surrounding the first sheet pattern, wherein the first lower pattern includes a first sidewall and a second sidewall opposite to each other, each of the first sidewall of the first lower pattern and the second sidewall of the first lower pattern extends in the first direction, the first gate electrode overlaps the first sidewall of the first lower pattern in the second direction by a first depth, the first gate electrode overlaps the second sidewall of the first lower pattern in the second direction by a second depth, and the first depth is different from the second depth.

Abstract: A semiconductor device includes a substrate, an active region disposed on the substrate and extending in a first direction, a device isolation layer adjacent to the active region, a gate structure disposed in the active region, the gate structure extending in a second direction crossing the first direction, and covering a portion of the device isolation layer, a gate separation pattern contacting an end of the gate structure, and an impurity region disposed below the gate separation pattern and on the device isolation layer.

Abstract: A semiconductor device includes a substrate, an active region disposed on the substrate and extending in a first direction, a device isolation layer adjacent to the active region, a gate structure disposed in the active region, the gate structure extending in a second direction crossing the first direction, and covering a portion of the device isolation layer, a gate separation pattern contacting an end of the gate structure, and an impurity region disposed below the gate separation pattern and on the device isolation layer.

Abstract: A method of fabricating a semiconductor device includes preparing a substrate including a first region and a second region, sequentially forming a first semiconductor layer and a second semiconductor layer on the first and second regions, patterning the first and second semiconductor layers to form a lower semiconductor pattern and an upper semiconductor pattern on each of the first and second regions, selectively removing the lower semiconductor pattern on the second region to form a gap region, and forming gate electrodes at the first and second regions, respectively.

Abstract: A semiconductor device includes at least one nanowire that is disposed over a substrate, extends to be spaced apart from the substrate, and includes a channel region, a gate that surrounds at least a part of the channel region, and a gate dielectric film that is disposed between the channel region and the gate. A source/drain region that contacts one end of the at least one nanowire is formed in a semiconductor layer that extends from the substrate to the one end of the at least one nanowire. Insulating spacers are formed between the substrate and the at least one nanowire. The insulating spacers are disposed between the gate and the source/drain region and are formed of a material that is different from a material of the gate dielectric film.

Abstract: A method of fabricating a semiconductor device includes preparing a substrate including a first region and a second region, sequentially forming a first semiconductor layer and a second semiconductor layer on the first and second regions, patterning the first and second semiconductor layers to form a lower semiconductor pattern and an upper semiconductor pattern on each of the first and second regions, selectively removing the lower semiconductor pattern on the second region to form a gap region, and forming gate electrodes at the first and second regions, respectively.

Abstract: A method of fabricating a semiconductor device includes preparing a substrate including a first region and a second region, sequentially forming a first semiconductor layer and a second semiconductor layer on the first and second regions, patterning the first and second semiconductor layers to form a lower semiconductor pattern and an upper semiconductor pattern on each of the first and second regions, selectively removing the lower semiconductor pattern on the second region to form a gap region, and forming gate electrodes at the first and second regions, respectively.

Abstract: A semiconductor device includes at least one nanowire that is disposed over a substrate, extends to be spaced apart from the substrate, and includes a channel region, a gate that surrounds at least a part of the channel region, and a gate dielectric film that is disposed between the channel region and the gate. A source/drain region that contacts one end of the at least one nanowire is formed in a semiconductor layer that extends from the substrate to the one end of the at least one nanowire. Insulating spacers are formed between the substrate and the at least one nanowire. The insulating spacers are disposed between the gate and the source/drain region and are formed of a material that is different from a material of the gate dielectric film.

Abstract: A method of fabricating a semiconductor device includes preparing a substrate including a first region and a second region, sequentially forming a first semiconductor layer and a second semiconductor layer on the first and second regions, patterning the first and second semiconductor layers to form a lower semiconductor pattern and an upper semiconductor pattern on each of the first and second regions, selectively removing the lower semiconductor pattern on the second region to form a gap region, and forming gate electrodes at the first and second regions, respectively.

Abstract: A semiconductor device includes at least one nanowire that is disposed over a substrate, extends to be spaced apart from the substrate, and includes a channel region, a gate that surrounds at least a part of the channel region, and a gate dielectric film that is disposed between the channel region and the gate. A source/drain region that contacts one end of the at least one nanowire is formed in a semiconductor layer that extends from the substrate to the one end of the at least one nanowire. Insulating spacers are formed between the substrate and the at least one nanowire. The insulating spacers are disposed between the gate and the source/drain region and are formed of a material that is different from a material of the gate dielectric film.

Abstract: A semiconductor device includes a substrate having a first region and a second region, a first MOS transistor including a first fin structure and a first gate electrode in the first region, the first fin structure having a first buffer pattern, a second buffer pattern, and a first channel pattern which are sequentially stacked on the substrate, and a second MOS transistor including a second fin structure and a second gate electrode in the second region, the second fin structure having a third buffer pattern and a second channel pattern which are sequentially stacked on the substrate. Related fabrication methods are also discussed.

Abstract: A semiconductor device includes a substrate including first and second regions, a first transistor provided on the first region to include a first channel region protruding from the substrate, and a second transistor provided on the second region to include a second channel region and a gate electrode extending between the substrate and the second channel region. The first channel region may include a lower semiconductor pattern containing a different material from the second channel region and an upper semiconductor pattern containing the same material as the second channel region.

Abstract: A semiconductor device includes a substrate having a first region and a second region, a first MOS transistor including a first fin structure and a first gate electrode in the first region, the first fin structure having a first buffer pattern, a second buffer pattern, and a first channel pattern which are sequentially stacked on the substrate, and a second MOS transistor including a second fin structure and a second gate electrode in the second region, the second fin structure having a third buffer pattern and a second channel pattern which are sequentially stacked on the substrate. Related fabrication methods are also discussed.