FinFET with Buried Insulator Layer and Method for Forming

A fin structure suitable for a FinFET and having a buried insulator layer is disclosed. In an exemplary embodiment, a semiconductor device comprises a substrate with a first semiconductor material and having a fin structure formed thereupon. The fin structure includes a lower region proximate to the substrate, a second semiconductor material disposed on the lower region, a third semiconductor material disposed on the second semiconductor material, and an insulating material selectively disposed on the second semiconductor material such that the insulating material electrically isolates a channel region of the fin structure and further such that the insulating material exerts a strain on the channel region. The semiconductor device further comprises an isolation feature disposed adjacent to the fin structure.