Semiconductor device

Abstract

A semiconductor device comprises an active pattern including a lower pattern and a plurality of sheet patterns that are spaced apart from the lower pattern in a first direction, a plurality of gate structures disposed on the lower pattern to be spaced apart from each other in a second direction, each of the gate structures including a gate electrode and gate insulating films, source/drain recesses defined between adjacent gate structures and a source/drain pattern filling the source/drain recesses. Each source/drain pattern may include a first semiconductor liner, which extend along sidewalls and a bottom surface of the source/drain recesses, second semiconductor liners, which are on the first semiconductor liners and extend along the sidewalls and the bottom surface of the source/drain recesses, and a filling semiconductor film, which is on the second semiconductor liners and fills the source/drain recess. The second semiconductor liners may be doped with carbon, and the first semiconductor liners may be in contact with the lower pattern and the sheet patterns, while the first semiconductor liners may include carbon-undoped regions.