Normal-Incidence Collector Optics for EUV Sources

Migura, Sascha, Carl Zeiss SMT GmbH; Müller, Tobias; Hartung, Frank, Carl Zeiss SMT GmbH

doi:10.1117/3.2638242.ch14

Book: Photon Sources for Lithography and Metrology

Editor(s): Vivek Bakshi

Chapter Author(s): Sascha Migura, Tobias Müller, Frank Hartung

Published: 2023

https://doi.org/10.1117/3.2638242.ch14

Author Affiliations +

Abstract

This chapter gives a brief introduction to the latest collector optics for EUV sources from an optics perspective. Section 14.2 explains some design rationales. The concept of the collector far field is described in Section 14.3, and its characteristic features are shown. In Section 14.4 we take a closer look at the individual wavelength ranges that determine the reflectivity of the collector. Section 14.5 continues with a brief introduction to the mechanics for the collector optics before Section 14.6 discusses the most important technological challenges related to production. The manufacturing of the collector mirror surface plays the key role. The collector mirror and the collector mechanics are combined to form the collector module. The last step in production is system qualification. Section 14.7 gives insight into the measures taken to counter the harsh environment to which the collector mirror is exposed, before Section 14.8 summarizes the chapter.