Semiconductor structure and method for forming the same

US11538685B2 · kind B2 · utility

Assignees

• Semiconductor Manufacturing International (Shanghai) Corporation · CN
• Semiconductor Manufacturing International (Beijing) Corporation · CN

Inventors

• Xiamei Tang · Shanghai, CN
• Wei Shi · Tangxia, CN
• Tao Dou · Hefei, CN
• Bo SU · Shanghai, CN
• Youcun Hu · Shanghai, CN

Key dates

• Filing date: Jul 15, 2020
• Grant date: Dec 27, 2022
• Expiry date: Apr 28, 2041

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/0337
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method of forming a semiconductor structure includes providing a to-be-etched layer, forming a core layer over the to-be-etched layer, the core layer including a first trench extending along a first direction, forming a sidewall spacer layer on a top surface of the core layer and on sidewalls and a bottom surface of the first trench, forming a block cut structure in the first trench after forming the sidewall spacer layer, and after forming the block cut structure, etching back the sidewall spacer layer until exposing the top surface of the core layer, thereby leaving a sidewall spacer on the sidewalls of the first trench. The block cut structure extends through the first trench along a second direction. The second direction and the first direction are different. The block cut structure includes a first block-cut layer and a second block-cut layer.