To suppress performance degradation of a semiconductor device, when the width of a first active region having a first field effect transistor formed therein is smaller than the width of a second active region having a second field effect transistor formed therein, the height of a surface of a first raised source layer of the first field effect transistor is made larger than the height of a surface of a second raised source layer of the second field effect transistor. Moreover, the height of a first surface of a raised drain layer of the first field effect transistor is made larger than a surface of a second raised drain layer of the second field effect transistor.