Abstract: A method for manufacturing a semiconductor device includes forming a semiconductor layer on a substrate, the semiconductor layer including a first semiconductor material and a second semiconductor material, patterning the semiconductor layer to form a preliminary active pattern, oxidizing at least two sidewalls of the preliminary active pattern to form an oxide layer on each of the at least two sidewalls of the preliminary active pattern, at least two upper patterns and a semiconductor pattern being formed in the preliminary active pattern when the oxide layers are formed, the semiconductor pattern being disposed between the at least two upper patterns, and removing the semiconductor pattern to form an active pattern, the active pattern including the at least two upper patterns. A concentration of the second semiconductor material in each of the at least two upper patterns is higher than a concentration of the second semiconductor material in the semiconductor pattern.

Abstract: A semiconductor memory device includes a substrate, a first active pattern on the substrate, a gate electrode intersecting a channel region of the first active pattern, a first insulating layer covering the first active pattern and the gate electrode, a contact penetrating the first insulating layer so as to be electrically connected to a first source/drain region of the first active pattern, and a second active pattern on the first insulating layer. A channel region of the second active pattern vertically overlaps with the contact.

Abstract: A semiconductor device includes an active pillar on a substrate. A first source/drain region is disposed at a top end of the active pillar and has a greater width than the active pillar. A first insulating layer is disposed on a sidewall of the active pillar and a second insulating layer is disposed on at least a bottom surface of the first source/drain region. A gate electrode is disposed on the first insulating layer and the second insulating layer. A second source/drain region is disposed in the substrate at a bottom end of the active pillar. Methods of fabrication are also described.

Abstract: A method for manufacturing a semiconductor device includes forming a semiconductor layer on a substrate, the semiconductor layer including a first semiconductor material and a second semiconductor material, patterning the semiconductor layer to form a preliminary active pattern, oxidizing at least two sidewalls of the preliminary active pattern to form an oxide layer on each of the at least two sidewalls of the preliminary active pattern, at least two upper patterns and a semiconductor pattern being formed in the preliminary active pattern when the oxide layers are formed, the semiconductor pattern being disposed between the at least two upper patterns, and removing the semiconductor pattern to form an active pattern, the active pattern including the at least two upper patterns. A concentration of the second semiconductor material in each of the at least two upper patterns is higher than a concentration of the second semiconductor material in the semiconductor pattern.

Abstract: A semiconductor device includes an active pattern provided on a substrate and a gate electrode crossing over the active pattern. The active pattern includes a first buffer pattern on the substrate, a channel pattern on the first buffer pattern, a doped pattern between the first buffer pattern and the channel pattern, and a second buffer pattern between the doped pattern and the channel pattern. The doped pattern includes graphene injected with an impurity.

Abstract: An integrated circuit device may include a substrate including a main surface, a compound semiconductor nanowire extending from the main surface in a first direction perpendicular to the main surface and including a first section and a second section alternately arranged in the first direction, a gate electrode covering the first section, and a gate dielectric layer between the first section and the gate electrode. The first section and the second section may have the same composition as each other and may have different crystal phases from each other.

Abstract: A method for manufacturing a semiconductor device includes forming a semiconductor layer on a substrate, the semiconductor layer including a first semiconductor material and a second semiconductor material, patterning the semiconductor layer to form a preliminary active pattern, oxidizing at least two sidewalls of the preliminary active pattern to form an oxide layer on each of the at least two sidewalls of the preliminary active pattern, at least two upper patterns and a semiconductor pattern being formed in the preliminary active pattern when the oxide layers are formed, the semiconductor pattern being disposed between the at least two upper patterns, and removing the semiconductor pattern to form an active pattern, the active pattern including the at least two upper patterns. A concentration of the second semiconductor material in each of the at least two upper patterns is higher than a concentration of the second semiconductor material in the semiconductor pattern.

Abstract: A semiconductor device includes an active pattern provided on a substrate and a gate electrode crossing over the active pattern. The active pattern includes a first buffer pattern on the substrate, a channel pattern on the first buffer pattern, a doped pattern between the first buffer pattern and the channel pattern, and a second buffer pattern between the doped pattern and the channel pattern. The doped pattern includes graphene injected with an impurity.

Abstract: An integrated circuit device includes a substrate, first and second fin active regions formed on the substrate and extending in a first direction parallel to a top surface of the substrate, a first gate structure disposed on a side surface of the first fin active region, a pair of first impurity regions respectively formed on a top portion and a bottom portion of the first fin active region, a second gate structure disposed on a side surface of the second fin active region, and a pair of second impurity regions respectively formed on a top portion or a bottom portion of the second fin active region, wherein the pair of first impurity regions vertically overlap each other, and the pair of second impurity regions do not vertically overlap each other.

Abstract: A semiconductor device includes an active pillar on a substrate. A first source/drain region is disposed at a top end of the active pillar and has a greater width than the active pillar. A first insulating layer is disposed on a sidewall of the active pillar and a second insulating layer is disposed on at least a bottom surface of the first source/drain region. A gate electrode is disposed on the first insulating layer and the second insulating layer. A second source/drain region is disposed in the substrate at a bottom end of the active pillar. Methods of fabrication are also described.

Abstract: A semiconductor device includes a substrate having a first region and a second region; a first nanowire in the first region in a direction perpendicular to an upper surface of the substrate; a second nanowire in the second region in a direction perpendicular to the upper surface of the substrate and having a height less than that of the first nanowire; first source/drain regions at top portion and bottom portion of the first nanowire; second source/drain regions at top portion and bottom portion of the second nanowire; a first gate electrode surrounding the first nanowire between the first source/drain regions; and a second gate electrode surrounding the second nanowire between the second source/drain regions.

Abstract: The present disclosure relates to a field-effect transistor and a method of fabricating the same. A field-effect transistor includes a semiconductor substrate including a first semiconductor material having a first lattice constant, and a fin structure on the semiconductor substrate. The fin structure includes a second semiconductor material having a second lattice constant that is different from the first lattice constant. The fin structure further includes a lower portion that is elongated in a first direction, a plurality of upper portions protruding from the lower portion and elongated in a second direction that is different from the first direction, and a gate structure crossing the plurality of upper portions.

Abstract: A semiconductor device includes an active pillar on a substrate. A first source/drain region is disposed at a top end of the active pillar and has a greater width than the active pillar. A first insulating layer is disposed on a sidewall of the active pillar and a second insulating layer is disposed on at least a bottom surface of the first source/drain region. A gate electrode is disposed on the first insulating layer and the second insulating layer. A second source/drain region is disposed in the substrate at a bottom end of the active pillar. Methods of fabrication are also described.

Abstract: A semiconductor device includes a semiconductor substrate including a first source/drain region formed in an upper portion of the semiconductor substrate, a metal silicide layer that covers a top surface of the first source/drain region, and a semiconductor pillar that penetrates the metal silicide layer and is connected to the semiconductor substrate. The semiconductor pillar includes a second source/drain region formed in an upper portion of the semiconductor pillar, a gate electrode on the metal silicide layer, with the gate electrode surrounding the semiconductor pillar in a plan view. A contact is connected to the metal silicide layer.

Abstract: The present disclosure relates to a field-effect transistor and a method of fabricating the same. A field-effect transistor includes a semiconductor substrate including a first semiconductor material having a first lattice constant, and a fin structure on the semiconductor substrate. The fin structure includes a second semiconductor material having a second lattice constant that is different from the first lattice constant. The fin structure further includes a lower portion that is elongated in a first direction, a plurality of upper portions protruding from the lower portion and elongated in a second direction that is different from the first direction, and a gate structure crossing the plurality of upper portions.

Abstract: An integrated circuit device may include a substrate including a main surface, a compound semiconductor nanowire extending from the main surface in a first direction perpendicular to the main surface and including a first section and a second section alternately arranged in the first direction, a gate electrode covering the first section, and a gate dielectric layer between the first section and the gate electrode.

Abstract: An integrated circuit device includes a substrate, first and second fin active regions formed on the substrate and extending in a first direction parallel to a top surface of the substrate, a first gate structure disposed on a side surface of the first fin active region, a pair of first impurity regions respectively formed on a top portion and a bottom portion of the first fin active region, a second gate structure disposed on a side surface of the second fin active region, and a pair of second impurity regions respectively formed on a top portion or a bottom portion of the second fin active region, wherein the pair of first impurity regions vertically overlap each other, and the pair of second impurity regions do not vertically overlap each other.

Abstract: A semiconductor device includes an active pillar on a substrate. A first source/drain region is disposed at a top end of the active pillar and has a greater width than the active pillar. A first insulating layer is disposed on a sidewall of the active pillar and a second insulating layer is disposed on at least a bottom surface of the first source/drain region. A gate electrode is disposed on the first insulating layer and the second insulating layer. A second source/drain region is disposed in the substrate at a bottom end of the active pillar. Methods of fabrication are also described.

Abstract: An integrated circuit device may include a substrate including a main surface, a compound semiconductor nanowire extending from the main surface in a first direction perpendicular to the main surface and including a first section and a second section alternately arranged in the first direction, a gate electrode covering the first section, and a gate dielectric layer between the first section and the gate electrode. The first section and the second section may have the same composition as each other and may have different crystal phases from each other.

Abstract: An integrated circuit device as provided herein may include a device region and an inter-device isolation region. Within the device region, a fin-type active region may protrude from a substrate, and opposite sidewalls of the fin-type active region may be covered by an inner isolation layer. An outer isolation layer may fill an outer deep trench in the inter-device isolation region. The inner isolation layer may extend away from the device region at an inner sidewall of the outer deep trench and into the inter-device isolation region. There may be multiple fin-type active regions, and trenches therebetween. The outer deep trench and the trenches between the plurality of fin-type active regions may be of different heights. The integrated circuit device and methods of manufacturing described herein may reduce a possibility that various defects or failures may occur due to an unnecessary fin-type active region remaining around the device region.