We have systematically investigated ultrathin Cr/Sc multilayers (nanolayers), using tunable soft-x-ray synchrotron radiation. The multilayers were optimized for use either in normal incidence or at 45° at photon energies around the 2p-absorption edges of Sc (399 eV) and Cr (574 eV), respectively. They were sputter deposited on Si wafers or on thin Si3N4-membrane support structures for use in reflection and in transmission, respectively, as polarizing and phase-retarding elements in a polarimeter. The performance theoretically expected with respect to reflection/transmission and energy resolution has been confirmed experimentally: A value of 7% for the normal-incidence peak reflectance at 395 eV was measured as well as a pronounced minimum in transmission for certain incidence angles and energies below the respective absorption edges, indicating significant phase-shifting effects.
© 1998 Optical Society of America
(120.5700) Instrumentation, measurement, and metrology : Reflection
(120.7000) Instrumentation, measurement, and metrology : Transmission
(230.4170) Optical devices : Multilayers
(350.5610) Other areas of optics : Radiation
Franz Schäfers, Hans-Christoph Mertins, Frank Schmolla, Ingo Packe, Nikolay N. Salashchenko, and Eugeny A. Shamov, "Cr /Sc Multilayers for the Soft-X-Ray Range," Appl. Opt. 37, 719-728 (1998)