Projection objective adapted for use with different immersion fluids or liquids, method of conversion of such and production method

US7589903B2 · kind B2 · utility

Assignee

• Carl Zeiss SMT GmbH · DE

Inventors

• Susanne Beder · Aalen, DE
• Wilhelm Ulrich · Aalen, DE
• Heiko Feldmann · Aalen, DE
• Wolfgang Singer · Aalen, DE
• Toralf Gruner · Hennef (Sieg), DE

Key dates

• Filing date: May 24, 2006
• Grant date: Sep 15, 2009
• Expiry date: Aug 7, 2027

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70341
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

The invention relates to a projection objective (6), in particular for applications in microlithography, serving to project an image of an object (3) arranged in an object plane (4) onto a substrate (18) arranged in an image plane (7). The projection objective (6) has an object-side-oriented part (10) which is arranged adjacent to the object plane (4) and includes a plurality of optical elements, and it also has an image-side-oriented part (11) of the objective which is arranged adjacent to the image plane (7) and includes a free space (16) serving to receive a fluid (13) and further includes at least a part of an optical end-position element (14) serving to delimit the free space (16) towards the object side. The projection objective (6) is operable in different modes of operation in which the free space (16) is filled with fluids (13) that differ in their respective indices of refraction.