Patent ID: 11876135
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  B | IPC H

Claim 15:
16. A method comprising:
forming a source/drain recess that extends a depth into a semiconductor substrate;
epitaxially growing a first semiconductor layer having a first dopant concentration in the source/drain recess, wherein the first semiconductor layer is disposed along sidewalls and a bottom of the source/drain recess, wherein a thickness of the first semiconductor layer along the bottom of the source/drain recess is less than the depth;
epitaxially growing a second semiconductor layer in the source/drain recess and over the first semiconductor layer, wherein the second semiconductor layer has a second dopant concentration greater than the first dopant concentration; and
replacing the semiconductor substrate with a dielectric substrate, wherein the second semiconductor layer physically contacts the dielectric substrate.