Illumination system particularly for EUV lithography

US6198793A · kind A · utility

Assignee

• Carl-Zeiss-Stiftung trading as Carl Zeiss · DE

Inventors

• Jorg Schultz · Aalen, DE
• Johannes Wangler · Oberkochen, DE
• Karl-Heinz Schuster · Oberkochen, DE
• Udo Dinger · Oberkochen, DE

Key dates

• Filing date: May 4, 1999
• Grant date: Mar 6, 2001
• Expiry date: May 4, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G21K2201/06
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

The invention concerns an illumination system for wavelengths .ltoreq.193 nm, particularly for EUV lithography, with at least one light source, which has an illumination A in a predetermined surface; at least one device for producing secondary light sources; at least one mirror or lens device comprising at least one mirror or one lens, which is or are organized into raster elements; one or more optical elements, which are arranged between the mirror or lens device comprising at least one mirror or one lens, which is or are organized into raster elements and the reticle plane, whereby the optical elements image the secondary light sources in the exit pupil of the illumination system. The illumination system is characterized by the fact that the raster elements of the one or more mirror or lenses are shaped and arranged in such a way that the images of the raster elements cover by means of the optical elements the major portion of the reticle plane and that the exit pupil defined by aperture and filling degree is illuminated.