Spectral tailoring of nanoscale EUV and soft x-ray multilayer optics
Extreme ultraviolet and soft X-ray (XUV) multilayer optics have experienced significant development over the past few years, particularly on controlling the spectral characteristics of light for advanced applications like EUV photolithography, space observation, and accelerator- or lab-based XUV exp...
Saved in:
Published in | Applied Physics Reviews Vol. 4; no. 1 |
---|---|
Main Authors | , , , , , |
Format | Book Review |
Language | English |
Published |
01.03.2017
|
Online Access | Get full text |
Cover
Loading…
Summary: | Extreme
ultraviolet and soft X-ray (XUV) multilayer optics have experienced significant development
over the past few years, particularly on controlling the spectral
characteristics of light for advanced applications like EUV photolithography, space
observation, and accelerator- or lab-based XUV experiments. Both planar and three
dimensional multilayer structures have been developed to tailor the spectral response
in a wide wavelength range. For the planar multilayer optics, different layered schemes are explored.
Stacks of periodic multilayers and capping layers are demonstrated to achieve
multi-channel reflection or suppression of the reflective properties. Aperiodic
multilayer
structures enable broadband reflection both in angles and wavelengths, with the
possibility of polarization control. The broad wavelength band multilayer is also used to
shape attosecond pulses for the study of ultrafast phenomena. Narrowband multilayer monochromators are
delivered to bridge the resolution gap between crystals and regular multilayers. High
spectral purity multilayers with innovated anti-reflection structures are shown to
select spectrally clean XUV radiation from broadband X-ray sources, especially the
plasma sources
for EUV
lithography. Significant progress is also made in the three dimensional multilayer optics, i.e.,
combining micro- and nanostructures with multilayers, in order to provide new freedom to tune the
spectral response. Several kinds of multilayer
gratings,
including multilayer coated gratings, sliced multilayer
gratings, and
lamellar multilayer
gratings are being
pursued for high resolution and high efficiency XUV spectrometers/monochromators, with
their advantages and disadvantages, respectively. Multilayer diffraction optics
are also developed for spectral purity enhancement. New structures
like gratings,
zone plates, and pyramids that obtain full suppression of the unwanted radiation and high XUV
reflectance are reviewed. Based on the present achievement of the spectral
tailoring multilayer optics, the remaining challenges and opportunities for
future researches are discussed. |
---|---|
ISSN: | 1931-9401 |
DOI: | 10.1063/1.4978290 |