FINFET Device with Wrapped-Around Epitaxial Structure and Manufacturing Method Thereof

A semiconductor device comprising:

• a substrate;
• an isolation structure over the substrate;
• first and second fins extending from the substrate and through the isolation structure, wherein each fin includes a channel region and two source/drain (S/D) regions sandwiching the channel region;
• a gate stack engaging each fin at the respective channel region;
• a first epitaxial layer over top and sidewall surfaces of the S/D regions of the first and second fins, the first epitaxial layer extending continuously from a position above the first fin to a position above the second fin;
• and
• a second epitaxial layer over top and sidewall surfaces of the first epitaxial layer, wherein a portion of the second epitaxial layer laterally between the first and second fins is directly under a bottom surface of the first epitaxial layer.

A semiconductor device comprising:

• a substrate;
• an isolation structure over the substrate;
• a fin extending from the substrate and through the isolation structure;
• a metal gate stack over a channel region of the fin;
• an epitaxial layer over top and sidewall surfaces of a source/drain (S/D) region of the fin;
• a gate spacer disposed on a sidewall of the metal gate stack, wherein the gate spacer separates the metal gate stack from physically contacting the epitaxial layer;
• a dielectric layer directly under the gate spacer and the metal gate stack, wherein the epitaxial layer physically contacts the dielectric layer;
• and
• a conductive feature disposed over and in electrical coupling with the epitaxial layer, wherein the conductive feature physically contacts the isolation structure.