FINFET WITH SIGMA CAVITY WITH MULTIPLE EPITAXIAL MATERIAL REGIONS

摘要

Embodiments of the present invention provide an improved finFET and methods of fabrication. A sigma cavity is used with an n-type finFET to allow multiple epitaxial layers to be disposed adjacent to a finFET gate. In some embodiments, stacking faults may be formed in the epitaxial layers using a stress memorization technique.

主权项

1. A method of forming a semiconductor structure, comprising:
forming a sigma cavity in a semiconductor substrate, wherein the sigma cavity is adjacent to a gate disposed on the semiconductor substrate; forming a first epitaxial material region in the sigma cavity, wherein a top surface of the first epitaxial material region is substantially planar with a top surface of the semiconductor substrate; and forming a second epitaxial material region disposed on the first epitaxial material region.