Semiconductor device and fabrication method thereof

US11587794B2 · kind B2 · utility

Assignees

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

Inventors

• Hai Yang Zhang · Shanghai, CN
• Yan Wang · Shanghai, CN
• Xin Jiang · Longbeilingcun, CN

Key dates

• Filing date: Oct 1, 2020
• Grant date: Feb 21, 2023
• Expiry date: May 11, 2041

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/31116
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A semiconductor device and fabrication method thereof are provided. The fabrication method include: providing a to-be-etched material layer; forming a plurality of discrete sacrificial layers on the to-be-etched material layer; forming first initial spacers on sidewalls of each of the discrete sacrificial layers. Each first initial spacer includes a first bottom region and a first top region on the first bottom region; removing the discrete sacrificial layers. The method further includes: removing the first top region of each first initial spacer to form a first spacer from each first bottom region; forming second spacers on sidewalls of each of the first spacers. Each second spacer includes a second bottom region and a second top region on the second bottom region; removing the first spacers; The method further includes: removing the second top regions by etching; and etching the to-be-etched material layer by using the second spacers as a mask.