Semiconductor structure and method for the forming same

US11011412B2 · kind B2 · utility

Assignees

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

Inventors

• Wei Shi · Tangxia, CN
• Youcun Hu · Shanghai, CN
• Xiamei Tang · Shanghai, CN

Key dates

• Filing date: Aug 30, 2019
• Grant date: May 18, 2021
• Expiry date: Aug 30, 2039

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76829
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A semiconductor structure and a method for forming same are provided. In one form, a forming method includes: providing a base, where a core layer is formed on the base, a hard mask layer is formed on the core layer, and a first mask opening is formed in the hard mask layer; forming a first mask trench in the core layer exposed from the first mask opening, the first mask trench including a plurality of mask sub-trenches along an extending direction, where the mask sub-trenches are isolated from each other using the core layer exposed from the first mask opening; forming a first spacer on a side wall of the mask sub-trench; removing a core layer of a region in which the first mask opening is located, and forming, at a position corresponding to the core layer, a second mask trench enclosed by the first spacer and the base, the second mask trench and the first mask trench being isolated from each other using the first spacer; and forming a second spacer on a side wall of the second mask trench, where both the first spacer and the base, and the second spacer and the base, enclose a first target trench. The first spacer and the second spacer whose side walls contact with each other are …