At least one gate dielectric, a gate electrode, and a gate cap dielectric are formed over at least one channel region of at least one semiconductor fin. A gate spacer is formed on the sidewalls of the gate electrode, exposing end portions of the fin on both sides of the gate electrode. The exposed portions of the semiconductor fin are vertically and laterally etched, thereby reducing the height and width of the at least one semiconductor fin in the end portions. Exposed portions of the insulator layer may also be recessed. A lattice-mismatched semiconductor material is grown on the remaining end portions of the at least one semiconductor fin by selective epitaxy with epitaxial registry with the at least one semiconductor fin. The lattice-mismatched material applies longitudinal stress along the channel of the finFET formed on the at least one semiconductor fin.