Carl Zeiss Smt Gmbh

Asml Netherlands B.v.

Gero Wittich

Guido Limbach

Norman Baer

Markus Hauf

Ulrich Loering

Stefan Hembacher

Timo Laufer

Holger Walter

Franz-Josef Stickel

Oliver Natt

Yim-Bun-Patrick Kwan

Jan Van Schoot

Peter Kuerz

Rolf Freimann

Thure Boehm

A projection lens of an EUV-lithographic projection exposure system with at least two reflective optical elements each comprising a body and a reflective surface for projecting an object field on a reticle onto an image field on a substrate if the projection lens is exposed with an exposure power of EUV light, wherein the bodies of at least two reflective optical elements comprise a material with a temperature dependent coefficient of thermal expansion which is zero at respective zero cross temperatures, and wherein the absolute value of the difference between the zero cross temperatures is more than 6K.

EUV exposure apparatus with reflective elements having reduced influence of temperature variation

A mirror (') with a substrate (S) and a layer arrangement configured such that light () having a wavelength below 250 nm and incident on the mirror at at least an angle of incidence of between 0&#xb0; and 30&#xb0; is reflected with more than 20% of its intensity. The layer arrangement has at least one surface layer system (P&#x2032;&#x2033;) having a periodic sequence of at least two periods (P) of individual layers, wherein the periods (P) include a high refractive index layer (H&#x2032;&#x2033;) and a low refractive index layer (L&#x2032;&#x2033;). The layer arrangement has at least one graphene layer. Use of graphene (G, SPL, B) on optical elements reduces surface roughness to below 0.1 nm rms HSFR and/or protects the EUV element against a radiation-induced volume change of more than 1%. Graphene is also employed as a barrier layer to prevent layer interdiffusion.

Mirror, projection objective with such mirror, and projection exposure apparatus for microlithography with such projection objective

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Aalen, Germany

Gero Wittich