Dual substrate orientation or bulk on SOI integrations using oxidation for silicon epitaxy spacer formation

摘要

A semiconductor process and apparatus provide a planarized hybrid substrate ( 15 ) by thermally oxidizing SOI sidewalls ( 90 ) in a trench opening ( 93 ) to form SOI sidewall oxide spacers ( 94 ) which are trimmed while etching through a buried oxide layer ( 80 ) to expose the underlying bulk substrate ( 70 ) for subsequent epitaxial growth of an epitaxial semiconductor layer ( 96 ). In this way, SOI sidewall oxide spacers ( 94 ) are formed that prevent epitaxial SOI sidewalls from being formed in the trench opening ( 93 ) during the epitaxial growth step, and that can be readily removed during any subsequent STI etch process