Epitaxial deposition-based processes for reducing gate dielectric thinning at trench edges and integrated circuits therefrom

Abstract

A method of fabricating an integrated circuit (IC) and ICs therefrom including a plurality of Metal Oxide Semiconductor (MOS) transistors having reduced gate dielectric thinning and corner sharpening at the trench isolation/semiconductor edge for gate dielectric layers generally 500 to 5,000 Angstroms thick. The method includes providing a substrate having a silicon including surface. A plurality of dielectric filled trench isolation regions are formed in the substrate. The silicon including surface forms trench isolation active area edges along its periphery with the trench isolation regions. An epitaxial silicon comprising layer is deposited, wherein the epitaxial comprising silicon layer is formed over the silicon comprising surface. The epitaxial comprising silicon layer is oxidized to convert at least a portion into a thermally grown silicon oxide layer, wherein the thermally grown silicon oxide layer provides at least a portion of a gate dielectric layer for at least one of said plurality of MOS transistors. A patterned gate electrode layer is formed over the gate dielectric, wherein the patterned gate electrode layer extends over at least one of the trench isolation active area edges. Fabrication of the IC is then completed.