Patent ID: 11923436
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 14:
15. A semiconductor structure, comprising:
a substrate;
a fin structure over the substrate, wherein:
the fin structure comprises a buffer layer in contact with the substrate and a channel layer in contact with the buffer layer;
the channel layer comprises silicon germanium with a first germanium atomic concentration; and
the buffer layer comprises silicon germanium with a second germanium atomic concentration different from the first germanium atomic concentration;

a gate structure over a first portion of the fin structure; and
a source/drain (S/D) region formed directly above a second portion of the fin structure, wherein the second portion of the fin structure separates the S/D region and the buffer layer, and wherein a first thickness of the channel layer of the first portion of the fin structure is greater than a second thickness of the channel layer of the second portion of the fin structure.