International Business Machines Corporation
Wrap around contact for nanosheet source drain epitaxy

Abstract:

Embodiments of the invention include a method for fabricating a semiconductor device and the resulting structure. A nanosheet stack of alternating nanosheets of a sacrificial semiconductor material and a semiconductor channel material located on a substrate is provided. An additional dielectric spacer is formed on the dielectric spacer and within a gap. Dielectric spacer is removed. An epitaxial oxide layer is formed on the re-exposed recessed surfaces of the substrate. Germanium is formed on the epitaxial oxide layer. Sidewalls of each semiconductor channel material nanosheet are physically exposed. A source/drain is formed on a surface of the germanium. ILD material is formed above each source/drain and above an adjacent region. Portions of ILD material are removed such that sidewalls of the source/drain and germanium are exposed. The germanium is removed. A contact region is formed that wraps around the source/drain region.