Patent ID: 11929409
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A semiconductor device structure, comprising:
a substrate having a plurality of fins formed from the substrate;
a first source/drain feature comprising:
a first epitaxial layer in contact with a first fin of the plurality of fins;
a second epitaxial layer formed on the first epitaxial layer; and
a third epitaxial layer formed on the second epitaxial layer, the third epitaxial layer comprising a center portion and an edge portion that is at a different height than the center portion; and
a fourth epitaxial layer formed on the third epitaxial layer; and

a second source/drain feature disposed adjacent to the first source/drain feature, the second source/drain feature comprising:
a first epitaxial layer in contact with a second fin of the plurality of fins;
a second epitaxial layer formed on the first epitaxial layer of the second source/drain feature;
a third epitaxial layer formed on the second epitaxial layer of the second source/drain feature, the third epitaxial layer comprising a center portion and an edge portion that is at a different height than the center portion of the third epitaxial layer of the second source/drain feature; and

a fourth epitaxial layer formed on the third epitaxial layer of the second source/drain feature,
wherein the center portion and the edge portion of the third epitaxial layer of the second source/drain feature are in contact with the center portion and edge portion of the third epitaxial layer of the first source/drain feature, respectively.