Embedded carbon-doped germanium as stressor for germanium nFET devices

摘要

Carbon-doped germanium stressor regions are formed in an nFET device region of a germanium substrate and at a footprint of a functional gate structure. The carbon-doped germanium stressor regions are formed by an epitaxial growth process utilizing monomethylgermane (GeH3—CH3) as the carbon source. The carbon-doped germanium stressor regions that are provided yield more strain in less volume since a carbon atom is much smaller than a silicon atom.

主权项

1. A method of forming a semiconductor structure, said method comprising:
providing a gate structure on a topmost surface of a germanium substrate and in an nFET device region of said germanium substrate; and forming a source-side carbon-doped germanium stressor region on one side of said gate structure, and a drain-side carbon-doped germanium stressor region on another side of said gate structure, wherein said forming said source-side carbon-doped germanium stressor region and said drain-side carbon-doped germanium stressor region comprises an epitaxial growth process utilizing monomethylgermane as a carbon source and wherein no silicon atoms are incorporated into said source-side carbon-doped germanium stressor region and said drain-side carbon-doped germanium stressor region.