Semiconductor device

Abstract

There is provided a semiconductor device comprising an active pattern, including a lower pattern extending in a first direction, and a plurality of sheet patterns spaced apart from the lower pattern in a second direction perpendicular to the first direction, a plurality of gate structures on the lower pattern to be spaced apart from each other in the first direction and including a gate electrode and a gate insulating film wrapping the plurality of sheet patterns, a source/drain recess defined between the gate structures adjacent to each other, and a source/drain pattern inside the source/drain recess and including a semiconductor blocking film formed continuously along the source/drain recess, wherein the source/drain recesses include a plurality of width extension regions, and a width of each of the width extension regions in the first direction increases and then decreases, as it goes away from an upper surface of the lower pattern.