Hybrid phase-shift mask

US6835510B2 · kind B2 · utility

Assignee

• ASML Masktools B.V. · NL

Inventors

• Jang Fung Chen · Cupertino, US
• Roger Caldwell · Tullahoma, US
• Thomas Laidig · Richmond, US
• Kurt E. Wampler · Sunnyvale, US

Key dates

• Filing date: Sep 16, 2003
• Grant date: Dec 28, 2004
• Expiry date: Sep 16, 2023

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F1/34
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A method of forming a hybrid mask for optically transferring a lithographic pattern corresponding to an integrated circuit from the mask onto a semiconductor substrate by use of an optical exposure tool. The method includes the steps of forming at least one non-critical feature on the mask utilizing one of a low-transmission phase-shift mask (pattern) and a non-phase shifting mask (pattern), and forming at least one critical feature on the mask utilizing a high-transmission phase-shift mask (pattern).