公开(公告)号：US20230317785A1

公开(公告)日：2023-10-05

申请号：US17712965

申请日：2022-04-04

Applicant: Taiwan Semiconductor Manufacturing Co., Ltd.

Inventor： Yung-Chun Yang ,  Wei Hao Lu ,  Wei-Min Liu ,  Li-Li Su ,  Chii-Horng Li ,  Yee-Chia Yeo

IPC: H01L29/06 ,  H01L29/786 ,  H01L29/66 ,  H01L21/8234

CPC classification number: H01L29/0665 ,  H01L29/78618 ,  H01L29/78696 ,  H01L29/66742 ,  H01L21/823418 ,  H01L21/823412

Abstract: A device includes a first nanostructure over a substrate and a first source/drain region adjacent the first nanostructure. The first source/drain region includes a first epitaxial layer covering a first sidewall of the first nanostructure. The first epitaxial layer has a first concentration of a first dopant. The first epitaxial layer has a round convex profile opposite the first sidewall of the first nanostructure in a cross-sectional view. The first source/drain region further includes a second epitaxial layer covering the round convex profile of the first epitaxial layer in the cross-sectional view. The second epitaxial layer has a second concentration of the first dopant, the second concentration being different from the first concentration.

公开(公告)号：US20230028591A1

公开(公告)日：2023-01-26

申请号：US17657822

申请日：2022-04-04

Applicant: Taiwan Semiconductor Manufacturing Co., Ltd.

Inventor： Tsz-Mei Kwok ,  Yung-Chun Yang ,  Cheng-Yen Wen ,  Li-Li Su ,  Yee-Chia Yeo

IPC: H01L29/786 ,  H01L29/04 ,  H01L29/06 ,  H01L29/423 ,  H01L21/02 ,  H01L29/66 ,  H01L21/285

Abstract: A method includes forming a protruding semiconductor stack including a plurality of sacrificial layers and a plurality of nanostructures, with the plurality of sacrificial layers and the plurality of nanostructures being laid out alternatingly. The method further includes forming a dummy gate structure on the protruding semiconductor stack, etching the protruding semiconductor stack to form a source/drain recess, and forming a source/drain region in the source/drain recess. The formation of the source/drain region includes growing first epitaxial layers. The first epitaxial layers are grown on sidewalls of the plurality of nanostructures, and a cross-section of each of the first epitaxial layers has a quadrilateral shape. The first epitaxial layers have a first dopant concentration. The formation of the source/drain region further includes growing a second epitaxial layer on the first epitaxial layers. The second epitaxial layer has a second dopant concentration higher than the first dopant concentration.