SEMICONDUCTOR DEVICE WITH METAL-DOPED SOURCE/DRAIN REGION

A semiconductor device includes: a substrate (100), an active pattern (101) extending in a first horizontal direction (DR1) on the substrate, a plurality of nanosheets (NW1 .. NW4) spaced apart from each other and stacked in a vertical direction on the active pattern, a gate electrode (G) extending in a second horizontal direction (DR2) different from the first horizontal direction on the active pattern, the gate electrode surrounding the plurality of nanosheets, a source/drain region (120) disposed on at least one side of the gate electrode on the active pattern, the source/drain region including a first layer (121) doped with a metal, and a second layer (122) disposed on the first layer, and an inner spacer (130) disposed between the gate electrode and the first layer, between each of the plurality of nanosheets, the inner spacer in contact with the first layer, the inner spacer including a metal oxide formed by oxidizing the same material as the metal.