Semiconductor structure and forming method thereof

US11404273B2 · kind B2 · utility

Assignees

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

Inventors

• Zhu Chen · Pequest, US
• He Zuopeng · Shanghai, CN
• Yang Ming · Shanghai, CN
• Yao Dalin · Shanghai, CN
• Bei Duohui · Shanghai, CN

Key dates

• Filing date: Jan 22, 2021
• Grant date: Aug 2, 2022
• Expiry date: Jan 22, 2041

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/31122
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

The present disclosure provides a semiconductor structure and a forming method thereof. One form of a forming method includes: providing a base; forming a plurality of discrete mandrel layers on the base, where an extending direction of the mandrel layers is a first direction, and a direction perpendicular to the first direction is a second direction; forming a plurality of spacer layers covering side walls of the mandrel layers; forming a pattern transfer layer on the base, where the pattern transfer layer covers side walls of the spacer layers; forming a first trench in the pattern transfer layer between adjacent spacer layers in the second direction; removing a mandrel layer to form a second trench after the first trench is formed; and etching the base along the first trench and the second trench to form a target pattern by using the pattern transfer layer and the spacer layer as a mask. In the present disclosure, the accuracy of the pattern transfer is improved.