a complementary metal - oxide semiconductor structure includes a substrate and a p - type field effect transistor and an n - type fet disposed adjacent to one another on the substrate . each fet includes a silicon - on - insulator region , a gate electrode disposed on the soi region , a source stressor , and a drain stressor disposed across from the source stressor relative to the gate electrode , wherein proximities of the source stressor and the drain stressor to a channel of a respective fet are substantially equal .