US Patent 11011643 Nanosheet FET including encapsulated all-around source/drain contact

A semiconductor device includes a semiconductor wafer having one or more suspended nanosheet extending between first and second source/drain regions. A gate structure wraps around the nanosheet stack to define a channel region located between the source/drain regions. The semiconductor device further includes a first all-around source/drain contact formed in the first source/drain region and a second all-around source/drain contact formed in the second source/drain region. The first and second all-around source/drain contacts each include a source/drain epitaxy structure and an electrically conductive external portion that encapsulates the source/drain epitaxy structure.