Microlithographic reduction objective, projection exposure equipment and process

US6349005B1 · kind B1 · utility

Assignee

• Carl Zeiss Stiftung · DE

Inventors

• Karl-Heinz Schuster · Oberkochen, DE
• Helmut Beierl · Heidenheim, DE

Key dates

• Filing date: Oct 12, 1999
• Grant date: Feb 19, 2002
• Expiry date: Oct 12, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70241
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A microlithographic projection objective with a lens arrangement, has a a first lens group of positive refractive power, a second lens group of negative refractive power, a third lens group of positive refractive power, a fourth lens group of negative refractive power, and a fifth lens group of positive refractive power. The system diaphragm (AS) is situated in the fifth lens group, and at least two lenses of this lens group are situated before the system diaphragm (AS). The numerical aperture on the image side is greater than 0.65 (in examples, up to 0.8), or this lens group has at least 13 lenses, or the system diaphragm (AS) is arranged in the region of the lens at which the pencil of rays assumes the greatest diameter, and its two adjacent lenses.