Comparison Among Multilayer Soft X-Ray Mirrors Fabricated By Electron Beam, Dc-, Rf-Magnetron Sputtering And Ion Beam Sputtering Deposition

Abstract

Multilayer Mo/Si mirrors have been fabricated by various physical vapor deposition methods. The best mirror fabricated by RF-magnetron sputtering showed a reflectivity of 57.8% at an incident angle of 25? and at a wavelength of 12.66 nm with synchrotron radiation reflectometer. The characteristics of fabricated multilayer mirrors have been measured using transmission electron microscope for surface and cross-sectional micrographs, electron diffraction for crystalline nature, small-angle x-ray diffractometer and synchrotron radiation reflectometer for reflectivity. Particularly, the dependencies of deposition parameters of Ar pressure and input power in RF-magnetron sputtering and substrate temperature in electron beam deposition in ultra high vacuum, have been investigated. The crystalization of Mo layers is clearly admitted for the mirrors by DC-and RF-magnetron sputtering. Surface roughness is minimum for the mirrors by RF-magnetron sputtering and ion beam sputtering. A possible reason of low reflectivity for the mirrors by ion beam sputtering is discussed from the resluts of additional analysis. ? 1988 SPIE.