TY - JOUR
T1 - Experimental study of EUV mirror radiation damage resistance under long-term free-electron laser exposures below the single-shot damage threshold
AU - Makhotkin, Igor A.
AU - Sobierajski, Ryszard
AU - Chalupsky, Jaromir
AU - Tiedtke, Kai
AU - de Vries, Gosse
AU - Störmer, Michael
AU - Scholze, Frank
AU - Siewert, Frank
AU - van de Kruijs, Robbert W.E.
AU - Milov, Igor
AU - Louis, Eric
AU - Jacyna, Iwanna
AU - Jurek, Marek
AU - Klinger, Dorota
AU - Nittler, Laurent
AU - Syryanyy, Yevgen
AU - Juha, Libor
AU - Hájková, Věra
AU - Vozda, Vojtěch
AU - Burian, Tomáš
AU - Saksl, Karel
AU - Faatz, Bart
AU - Keitel, Barbara
AU - Plonjes, Elke
AU - Schreiber, Siegfried
AU - Toleikis, Sven
AU - Loch, Rolf
AU - Hermann, Martin
AU - Strobel, Sebastian
AU - Nienhuys, Han Kwang
AU - Gwalt, Grzegorz
AU - Mey, Tobias
AU - Enkisch, Hartmut
N1 - Wiley deal
PY - 2018/1
Y1 - 2018/1
N2 - 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, the Free-electron LASer in Hamburg, using 13.5 nm extreme UV (EUV) 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 20° and 10° grazing incidence, respectively. Mo/Si periodical multilayer structures were tested in the Bragg reflection condition at 16° off-normal angle of incidence. The exposed areas were analysed post-mortem using differential contrast visible light microscopy, EUV reflectivity mapping and scanning X-ray photoelectron spectroscopy. 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.
AB - 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, the Free-electron LASer in Hamburg, using 13.5 nm extreme UV (EUV) 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 20° and 10° grazing incidence, respectively. Mo/Si periodical multilayer structures were tested in the Bragg reflection condition at 16° off-normal angle of incidence. The exposed areas were analysed post-mortem using differential contrast visible light microscopy, EUV reflectivity mapping and scanning X-ray photoelectron spectroscopy. 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.
KW - UT-Hybrid-D
KW - EUV optics
KW - Thin Films
KW - FELs
KW - Free-electron laser induced damage
KW - Free-Electron laser induced damage
KW - thin films
UR - http://www.scopus.com/inward/record.url?scp=85038971075&partnerID=8YFLogxK
U2 - 10.1107/S1600577517017362
DO - 10.1107/S1600577517017362
M3 - Article
SN - 0909-0495
VL - 25
SP - 77
EP - 84
JO - Journal of synchrotron radiation
JF - Journal of synchrotron radiation
IS - 1
ER -