Optics and Multilayer Coatings for EUVL Systems

Soufli, Regina; Bajt, Saša; Hudyma, Russell M.; Taylor, John S.

doi:10.1117/3.769214.ch4a

Book: EUV Lithography

Editor(s): Vivek Bakshi

Author(s): Regina Soufli, Saša Bajt, Russell Hudyma, John Taylor

Published: 2008

https://doi.org/10.1117/3.769214.ch4a

Abstract

EUV lithography (EUVL) employs illumination wavelengths around 13.5 nm, and in many aspects it is considered an extension of optical lithography, which is used for the high-volume manufacturing (HVM) of today's microprocessors. The EUV wavelength of illumination dictates the use of reflective optical elements (mirrors) as opposed to the refractive lenses used in conventional lithographic systems. Thus, EUVL tools are based on all-reflective concepts: they use multilayer (ML) coated optics for their illumination and projection systems, and they have a ML-coated reflective mask.