Methods for manufacturing a field-effect semiconductor device

Abstract

A method of fabricating a field-effect transistor is disclosed. In one aspect, the method includes forming a channel layer comprising germanium over a substrate. The method additionally includes forming a gate structure on the channel layer, where the gate structure comprises a gate layer comprising silicon, and the gate layer has sidewalls above a surface of the channel layer. The method additionally includes forming sidewall spacers comprising silicon dioxide on the sidewalls by subjecting the gate structure to a solution adapted for forming a chemical silicon oxide on materials comprising silicon. The method further includes forming elevated source/drain structures on the channel layer adjacent to the gate structure by selectively epitaxially growing a source/drain material on the channel layer.