Patent ID: 11869765
Assignee: SAMSUNG ELECTRONICS CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  B | IPC B  H

Claim 17:
18. A semiconductor device, comprising:
a substrate;
an isolation layer on the substrate;
an active region penetrating through the isolation layer and extending in a first direction;
a source/drain on a first portion of the active region;
a plurality of active layers on a second portion of the active region and spaced apart from each other in a vertical direction;
a gate structure on the second portion of the active region, and covering an upper surface, a side surface, and a lower surface of each of the plurality of active layers;
an interlayer insulating layer on the isolation layer and the source/drain;
a contact structure penetrating through the interlayer insulating layer and contacting the source/drain; and
an insulating spacer between the interlayer insulating layer and the contact structure,
wherein the source/drain includes:
a base epitaxial region on the first portion of the active region;
a first epitaxial region on the base epitaxial region and having a recessed surface; and
a second epitaxial region on the recessed surface of the first epitaxial region,

wherein the second epitaxial region vertically overlaps the insulating spacer and the contact structure,
wherein the plurality of active layers include a lower active layer, an intermediate active layer on the lower active layer, and an upper active layer on the intermediate active layer,
wherein the contact structure includes a metal-semiconductor compound layer and a contact plug on the metal-semiconductor compound layer,
wherein the metal-semiconductor compound layer contacts the second epitaxial region and is spaced apart from the first epitaxial region,
wherein a lower end of the second epitaxial region is at a lower level than a lower surface of the upper active layer,
wherein an upper end of the first epitaxial region is at a higher level than the lower surface of the upper active layer, and
wherein the first direction is parallel to an upper surface of the substrate.