公开(公告)号：US20220157936A1

公开(公告)日：2022-05-19

申请号：US17097959

申请日：2020-11-13

Applicant: Taiwan Semiconductor Manufacturing Co., Ltd.

Inventor： Mrunal Abhijith KHADERBAD ,  Dhanyakumar Mahaveer SATHAIYA ,  Huicheng CHANG ,  Ko-Feng CHEN ,  Keng-Chu LIN

IPC: H01L29/06 ,  H01L27/092 ,  H01L29/66 ,  H01L29/78 ,  H01L21/8238

Abstract: The present disclosure is directed to a method for the fabrication of isolation structures between source/drain (S/D)) epitaxial structures of stacked transistor structures. The method includes depositing an oxygen-free dielectric material in an opening over a first epitaxial structure, where the oxygen-free dielectric material covers top surfaces of the first epitaxial structure and sidewall surfaces of the opening. The method also includes exposing the oxygen-free dielectric material to an oxidizing process to oxidize the oxygen-free dielectric material so that the oxidizing process does not oxidize a portion of the oxygen-free dielectric material on the first epitaxial structure. Further, etching the oxidized oxygen-free dielectric material and forming a second epitaxial layer on the oxygen-free dielectric material not removed by the etching to substantially the opening.