Pupil facet mirror, optical system and illumination optics for a projection lithography system

US11169445B2 · kind B2 · utility

Assignee

• Carl Zeiss SMT GmbH · DE

Inventors

• Stig Bieling · Aalen, DE
• Martin Endres · Oberkochen, DE
• Thomas Fischer · Umkirch, DE

Key dates

• Filing date: May 12, 2020
• Grant date: Nov 9, 2021
• Expiry date: May 12, 2040

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70116
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An optical system includes an illumination optical unit configured to guide illumination radiation along a path to an object plane. The illumination optical unit includes comprising a first facet mirror; a second facet mirror disposed downstream of the first facet mirror along the path; and a condenser mirror. The optical system also includes a projection optical unit configured to image a first article in the object plane onto a second article in an image plane. The image plane is a first distance from the object plane. The condenser mirror a second distance from the object plane. The second distance is greater than the first distance