Illumination system particularly for microlithography

US7592598B2 · kind B2 · utility

Assignee

• Carl Zeiss SMT GmbH · DE

Inventors

• Hans-Juergen Mann · Oberkochen, DE
• Wolfgang Singer · Aalen, DE
• Joerg Schultz · Aalen, DE
• Johannes Wangler · Oberkochen, DE
• Karl-Heinz Schuster · Oberkochen, DE
• Udo Dinger · Oberkochen, DE
• Martin Antoni · Aalen, DE
• Wilhelm Ulrich · Aalen, DE

Key dates

• Filing date: Oct 24, 2008
• Grant date: Sep 22, 2009
• Expiry date: Oct 24, 2028

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70358
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

There is provided a projection objective for a projection exposure apparatus that has a primary light source for emitting electromagnetic radiation having a chief ray with a wavelength ≦193 nm. The projection objective includes an object plane, a first mirror, a second mirror, a third mirror, a fourth mirror; and an image plane. The object plane, the first mirror, the second mirror, the third mirror, the fourth mirror and the image plane are arranged in a centered arrangement around a common optical axis. The first mirror, the second mirror, the third mirror, and the fourth mirror are situated between the object plane and the image plane. The chief ray, when incident on an object situated in the object plane, in a direction from the primary light source, is inclined away from the common optical axis.