title: Extreme ultraviolet performance of a multilayer coated high density toroidal grating.
abstract: The performance of a multilayer coated diffraction grating has been evaluated at EUV wavelengths both in terms of absolute efficiency and spectral resolution. The application of a ten-layer Ir/Si multilayer coating to a 3600-lines/mm blazed toroidal replica grating produced a factor of 9 enhancement in peak efficiency near the design wavelength approximately 30 nm in first order, without degrading its excellent quasistigmatic spectral resolution. The measured EUV efficiency peaked at 3.3% and was improved over the full spectral range between 25 and 35 nm compared with the premultilayer replica which had a standard gold coating. In addition, the grating's spectral resolution of >5000 was maintained.
authors.forename: R J
authors.initials: RJ
authors.lastname: Thomas
authors.forename: R A
authors.initials: RA
authors.lastname: Keski-Kuha
authors.forename: W M
authors.initials: WM
authors.lastname: Neupert
authors.forename: C E
authors.initials: CE
authors.lastname: Condor
authors.forename: J S
authors.initials: JS
authors.lastname: Gum