The present disclosure provides a semiconductor structure. The semiconductor structure includes a semiconductor substrate having a first region and a second region; a first fin active region of a first semiconductor material disposed within the first region, oriented in a first direction, wherein the first fin active region has a crystalline direction along the first direction; and a second fin active region of a second semiconductor material disposed within the second region and oriented in the first direction, wherein the second fin active region has a crystalline direction along the first direction.