Integrated circuit device

An integrated circuit device comprising:

• an active region extending in a first horizontal direction on a substrate;
• a plurality of channel layers apart from each other on the active region in a vertical direction, and extending in the first horizontal direction;
• a first oxide layer and a second oxide layer apart from each other, the plurality of channel layers therebetween;
• a gate line extending on the active region in a second horizontal direction crossing the first horizontal direction, and surrounding the plurality of channel layers, the first oxide layer, and the second oxide layer;
• a source/drain region on the active region and in contact with the plurality of channel layers;
• and
• an inner spacer comprising:
• one sidewall in contact with a sidewall of the source/drain region;
• another sidewall opposite the one sidewall and covering a sidewall of the gate line;
• and
• an upper surface and a lower surface, each in contact with the plurality of channel layers,
• wherein the plurality of channel layers comprise a transition metal dichalcogenide (TMD) compound, and
• wherein each of the plurality of channel layers comprises a plurality of convex curved units in the vertical direction.

An integrated circuit device comprising:

• an active region extending in a first horizontal direction on a substrate;
• a nanosheet stack comprising a plurality of nanosheets apart from an upper surface of the active region in a vertical direction;
• a gate line extending on the active region in a second horizontal direction crossing the first horizontal direction, and surrounding the plurality of nanosheets, the gate line comprising a sub-gate between adjacent ones of the plurality of nanosheets in the vertical direction and between a lowermost nanosheet of the plurality of nanosheets and the active region, and on an uppermost nanosheet of the plurality of nanosheets;
• a source/drain region in contact with the plurality of nanosheets;
• an insulating spacer on sidewalls of the gate line;
• an inner spacer between the sub-gate and the source/drain region;
• and
• a first oxide layer between lower surfaces of the plurality of nanosheets and the gate line,
• wherein the inner spacer is between the first oxide layer and the source/drain region, and
• wherein the plurality of nanosheets comprise a transition metal dichalcogenide (TMD) compound, and upper surfaces and lower surfaces of the plurality of nanosheets comprise a plurality of convex uneven units in the vertical direction.