Illumination system for a microlithgraphic exposure apparatus

US8873151B2 · kind B2 · utility

Assignee

• Carl Zeiss SMT GmbH · DE

Inventors

• Alexander Sohmer · Oberkochen, DE
• Aurelian Dodoc · Heidenheim an der Brenz, DE
• Heiko Feldmann · Aalen, DE
• Wilhelm Ulrich · Aalen, DE
• Gerhard Fuerter · Ellwangen, DE
• Rafael Egger · Munich, DE
• Artur Moegele · Oberkochen, DE
• Michael Raum · Oberkochen, DE

Key dates

• Filing date: Apr 26, 2006
• Grant date: Oct 28, 2014
• Expiry date: Jul 24, 2030

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B27/0043
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An illumination system of a microlithographic exposure apparatus comprises a condenser for transforming a pupil plane into a field plane. The condenser has a lens group that contains a plurality of consecutive lenses. These lenses are arranged such that a light bundle focused by the condenser on an on-axis field point converges within each lens of the lens group. At least one lens of the lens group has a concave surface. The illumination system may further comprise a field stop objective that at least partly corrects a residual pupil aberration of the condenser.