Open AccessHigh efficiency structured EUV multilayer mirror for spectral filtering of long wavelengths
Author(s) -
Qiushi Huang,
M. de Boer,
J.L.P. Barreaux,
Robert van der Meer,
Eric Louis,
F. Bijkerk
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.019365
Subject(s) - extreme ultraviolet lithography , extreme ultraviolet , optics , wavelength , materials science , radiation , diffraction , optoelectronics , physics , laser
High spectral purity at longer wavelength side is demanded in many extreme ultraviolet (EUV) and soft X-ray (together also referred to as XUV) optical systems. It is usually obtained at the expense of a high loss of XUV efficiency. We proposed and developed a new method based on a periodic, tapered structure integrated with an EUV multilayer. The longer wavelength radiation is scattered/diffracted away by the tapered multilayer structure while the EUV light is reflected. The first proof-of-principle showed a broadband suppression from λ = 100-400 nm with an average factor of 14. Moreover, a high EUV reflectance of 64.7% was achieved, which corresponds to 94% of the efficiency of a regular EUV multilayer mirror.