• Uschakow, S.; Gaupp, A.; Gerhard, M.; MacDonald, M.; Schäfers, F.: Polarization properties of Mo/Si multilayers in the EUV range. Nuclear Instruments & Methods in Physics Research A 710 (2013), p. 120-124

10.1016/j.nima.2012.10.133

Abstract:
We investigatepolarizationpropertiesoftwonovelreflectiveMo/Simultilayers(ML)intheEUVrange usingpolarizedsynchrotronradiationattheBESSY-IIstorageringfacility.OneoftheMo/SiMLisusedas a retarder,theotheroneasananalyzerwithintheexperimentalsetupoftheBESSYsoft-x-ray polarimeter.Theanalyzermultilayerischaracterizedbyperformingreflectivitymeasurementswith s- andp-polarizedlightasafunctionoftheincidenceanglefordifferentwavelengths.Thecharacteriza- tionoftheretardermultilayerconsistsofreflectivitymeasurementswiths-andp-polarizedlightasa functionofthewavelengthforthreedifferentanglesnearnormalincidence.Inadditionthephase retardanceonreflectionwasdeterminedforoneangleofincidenceasfunctionofwavelength. Uncertaintiesofthephaseretardanceareestimatedviatheblockbootstrapmethod.Asanadditional by-productoftheMLcharacterizationtheStokesparametersofthebeamlinecouldbedetermined.With the 8-axisBESSYpolarimeterwehavemeasuredthecomplexreflectioncoefficientsforthefirsttimeand establishedthisellipsometrytechniqueasanadditionalprobetocharacterizemultilayeroptical elements.