A table-top EUV focusing optical system with high energy density using a modified Schwarzschild objective and a laser-plasma light source

Zhe Zhang; Wenbin Li; Qiushi Huang; Zhong Zhang; Shengzhen Yi; Liuyang Pan; Chun Xie; Przemyslaw Wachulak; Henryk Fiedorowicz; Zhanshan Wang

doi:10.1063/1.5044752

A table-top EUV focusing optical system with high energy density using a modified Schwarzschild objective and a laser-plasma light source

Rev Sci Instrum. 2018 Oct;89(10):103109. doi: 10.1063/1.5044752.

Authors

Affiliations

¹ MOE Key Laboratory of Advanced Micro-Structured Materials, No. 1239 Siping Road, 200092 Shanghai, China.
² Sino-German College of Applied Sciences, Tongji University, 200092 Shanghai, China.
³ Institute of Optoelectronics, Military University of Technology, ul. W. Urbanowicza 2, 00-908 Warsaw, Poland.

PMID: 30399967
DOI: 10.1063/1.5044752

Abstract

For investigating extreme ultraviolet (EUV) damage on optics, a table-top EUV focusing optical system was developed in the laboratory. Based on a modified Schwarzschild objective with a large numerical aperture and a laser-plasma light source, this optical system can generate a focusing spot with the maximum energy density of 2.27 J/cm² at the focal plane of the objective at the wavelength of 13.5 nm. The structures and the characterized properties of this optical system are presented in this paper. For testing the performance of this setup, single-shot EUV damage tests were carried out on an optical substrate of CaF₂ and a gold thin film. The damage thresholds and morphologies of these samples were given and discussed with former research studies.