Patent ID: 8637954

Claim:
A semiconductor die, comprising: a substrate; a first epitaxial layer on the substrate; a second epitaxial layer that is formed on a portion of the first epitaxial layer; a first device region including the first epitaxial layer and one or more semiconductor devices of a first type formed in the first epitaxial layer of the first device region; a second device region spaced apart from the first device region and including the second epitaxial layer and one or more semiconductor devices of a second type formed in the second epitaxial layer of the second device region; wherein the first epitaxial layer is different than the second epitaxial layer so that the one or more semiconductor devices of the first type are formed in a different epitaxial layer than the one or more semiconductor devices of the second type; and wherein the first epitaxial layer forms a continuous layer on the substrate between the first device region and the second device region.