Semiconductor devices and fabrication methods thereof

US11430657B2 · kind B2 · utility

Assignees

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

Inventors

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

Key dates

• Filing date: Feb 28, 2020
• Grant date: Aug 30, 2022
• Expiry date: Jul 31, 2040

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76816
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method for fabricating a semiconductor device includes providing a to-be-etched layer, including alternately arranged first regions and second regions in a first direction. Each first region adjoins adjacent second regions, and each second region includes a trench region. The method includes forming a first mask layer on the to-be-etched layer; implanting doping ions into the first mask layer outside of the trench region; forming a doped separation layer in the first mask layer of the second region to divide the first mask layer into portions arranged in a second direction perpendicular to the first direction; forming a first trench in the first mask layer of the first region; and removing the first mask layer formed in the trench region on both sides of the doped separation layer to form a second trench divided into portions arranged in the second direction by the doped separation layer.