Patent ID: 11888046
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 13:
14. A semiconductor device, comprising:
a substrate;
a first fin structure and a second fin structure on the substrate, wherein the first and second fin structures are separated by a first spacing;
a third fin structure and a fourth fin structure on the substrate, wherein the third and fourth fin structures are separated by a second spacing greater than the first spacing;
a merged epitaxial region over the first and second fin structures;
unmerged epitaxial regions over the third and fourth fin structures, respectively; and
an epitaxial buffer region over a top surface of the merged epitaxial region and not over top surfaces of the unmerged epitaxial regions, wherein a length of a horizontal interface between the epitaxial buffer region and the merged epitaxial region is greater than the first spacing, and wherein a height of the merged epitaxial region is greater than heights of the unmerged epitaxial regions.