A semiconductor device including first fin-shaped patterns in a first region of a substrate and spaced apart from each other in a first direction, second fin-shaped patterns in a second region of the substrate and spaced apart from each other in a second direction, a first field insulating film on the substrate and covering sidewalls of the first fin-shaped patterns, a second field insulating film on the substrate and covering sidewalls of the second fin-shaped patterns, a first source/drain pattern on the first field insulating film, connected to the first fin-shaped patterns, and including a first silicon-germanium pattern, and a second source/drain pattern on the second field insulating film, connected to the second fin-shaped patterns, and including a second silicon-germanium pattern, the second source/drain pattern and the second field insulating film defining one or more first air gaps therebetween may be provided.