Photolithography alignment mark structures and semiconductor structures

US10163806B2 · kind B2 · utility

Assignee

• Semiconductor Manufacturing International (Shanghai) Corporation · CN

Inventors

• Boxiu Cai · Shanghai, CN
• Yi Huang · Shanghai, CN

Key dates

• Filing date: Feb 28, 2017
• Grant date: Dec 25, 2018
• Expiry date: Mar 3, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2924/0002
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A method is provided for fabricating a photolithography alignment mark structure. The method includes providing a substrate; forming a first grating, a second grating, a third grating and a fourth grating in the substrate; forming a photoresist layer on a surface of the substrate; obtaining a first alignment center along a first direction and a second alignment center alone a second direction based on the first grating and the fourth grating, respectively; providing a mask plate having a fifth grating pattern and a sixth grating pattern; aligning the mask plate with the substrate by using the first alignment center as an alignment center along the first direction and the second alignment center as an alignment center along the second direction; reproducing the fifth grating pattern and the sixth grating pattern in the photoresist layer; and forming a fifth grating and a sixth grating on the substrate by removing a portion of photoresist layer.