Catadioptric projection objective with intermediate images

US8107162B2 · kind B2 · utility

Assignee

• Carl Zeiss SMT GmbH · DE

Inventors

• Aurelian Dodoc · Heidenheim an der Brenz, DE
• Wilhelm Ulrich · Aalen, DE
• Alexander Epple · Aalen, DE

Key dates

• Filing date: May 13, 2005
• Grant date: Jan 31, 2012
• Expiry date: May 25, 2027

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70275
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A catadioptric projection objective for imaging of a pattern, which is arranged on the object plane of the projection objective, on the image plane of the projection objective has a first objective part for imaging of an object field to form a first real intermediate image, a second objective part for production of a second real intermediate image using the radiation coming from the first objective part; and a third objective part for imaging of the second real intermediate image on the image plane. The second objective part is a catadioptric objective part with a concave mirror. A first folding mirror for deflection of the radiation coming from the object plane in the direction of the concave mirror and a second folding mirror for deflection of the radiation coming from the concave mirror in the direction of the image plane are provided. A field lens with a positive refractive power is arranged between the first intermediate image and/or the first folding mirror and the concave mirror, in an area close to the field of the first intermediate image.