Finfet including improved epitaxial topology

摘要

A semiconductor device includes a semiconductor substrate having a plurality of semiconductor fins formed on an upper surface thereof. An epitaxial material is formed on the upper surface of the semiconductor substrate and on an outer surface of the semiconductor fins. The epitaxial material includes an epi upper surface having a lower region that contacts the semiconductor fins and an upper region formed above the lower region. The upper region extends parallel with an upper surface of the semiconductor fins.

主权项

1. A method of fabricating a semiconductor device, the method comprising:
forming a plurality of semiconductor fins having a fin height on an upper surface of a semiconductor substrate; growing an epitaxial material on the upper surface of the semiconductor substrate and on an outer surface of the semiconductor fins, the epitaxial material including an epi upper surface having a lower region that contacts the semiconductor fins and an upper region formed above the lower region, the lower region and the upper region defining a first height differential therebetween; recessing the upper region to define a second height differential that is less than the first height differential and to increase the flatness of the epi upper surface without reducing the fin height, wherein recessing the upper region forms a plurality of recessed peak regions having an increased flatness with respect to the upper region before the recessing is performed; and annealing the epi upper surface after the recessing of the upper region such that a height of the upper region is reduced to define a third height differential that is less than the second height differential, the annealing smoothening the recessed upper region to form a smoothened upper surface extending continuously between opposing ends of the semiconductor device.