US Patent 11670551 Interface trap charge density reduction

The present disclosure provides methods of fabricating a semiconductor device. A method according to one embodiment includes forming, on a substrate, a first fin formed of a first semiconductor material and a second fin formed of a second semiconductor material different from the first semiconductor material, forming a semiconductor cap layer over the first fin and the second fin, and annealing the semiconductor cap layer at a first temperature while at least a portion of the semiconductor cap layer is exposed.