Localized region of isolated silicon over recessed dielectric layer

Abstract

An integrated circuit is formed by forming an isolation recess in a single crystal substrate which includes silicon, filling the isolation recess with isolation dielectric material, and planarizing the isolation dielectric material to be coplanar with the top surface of the substrate to form a buried isolation layer. A non-selective epitaxial process forms single-crystalline silicon-based semiconductor material on exposed areas of the substrate and polycrystalline or amorphous silicon-based material on the buried isolation layer. A cap layer is formed over the epitaxial silicon-based material, and a radiantly-induced recrystallization process causes the polycrystalline or amorphous silicon-based material to form single-crystalline semiconductor over the buried isolation layer.