Experimental study of EUV mirror radiation damage resistance under long-term free-electron laser exposures below the single-shot damage threshold

0487414 - FZÚ 2019 RIV GB eng J - Journal Article
Makhotkin, I. - Sobierajski, R. - Chalupský, Jaromír - Tiedtke, K. - de Vries, G. - Stoermer, M. - Scholze, F. - Siewert, F. - van de Kruijs, R.W.E. - Milov, I. - Louis, E. - Jacyna, I. - Jurek, M. - Klinger, D. - Nittler, L. - Syryanyy, Y. - Juha, Libor - Hájková, Věra - Vozda, Vojtěch - Burian, Tomáš - Saksl, Karel - Faatz, B. - Keitel, B. - Ploenjes, E. - Schreiber, S. - Toleikis, S. - Loch, R.A. - Hermann, M. - Strobel, S. - Nienhuys, H.-K. - Gwalt, G. - Mey, T. - Enkisch, H.
Experimental study of EUV mirror radiation damage resistance under long-term free-electron laser exposures below the single-shot damage threshold.
Journal of Synchrotron Radiation. Roč. 25, č. 1 (2018), s. 77-84. ISSN 0909-0495. E-ISSN 1600-5775.
[Workshop on FEL Photon Diagnostics, Instrumentation and Beamline Design (PhotonDiag2017). Stanford, 01.05.2017-03.05.2017]
R&D Projects: GA MŠMT LG15013; GA ČR(CZ) GA17-05167s; GA ČR(CZ) GA14-29772S
Institutional support: RVO:68378271
Keywords : free-electron laser induced damage * EUV optics * thin films * FELs
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 2.452, year: 2018

The durability of grazing-and normal-incidence optical coatings has been experimentally assessed under free-electron laser irradiation at various numbers of pulses up to 16 million shots and various fluence levels below 10% of the single-shot damage threshold. The experiment was performed at FLASH, using 13.5-nm radiation with 100 fs pulse duration. Polycrystalline ruthenium and amorphous carbon 50 nm thin films on silicon substrates were tested at total external reflection angles of 20degrees and 10degrees grazing incidence, respectively. Mo/Si periodical multilayer structures were tested in the Bragg reflection condition at 16degrees off-normal angle of incidence. The analysis revealed that Ru and Mo/Si coatings exposed to the highest dose and fluence level show a few per cent drop in their EUV reflectivity, which is explained by EUV-induced oxidation of the surface.
Permanent Link: http://hdl.handle.net/11104/0283325