Integration of epitaxial structures

摘要

This is method for forming epitaxial structures on a substrate which comprises: forming a first epi layer on the substrate; removing one or more substantial portions of the first epi layer; forming a second epi layer over the first epi layer and adjacent said first epi layer; forming a masking layer over portions of the second epi layer which are not over the first epi layer; and substantially removing a portion of the second epi layer which is over the first epi layer to provide a substantially planar structure having different properties. Other devices and methods are also disclosed.