Accession Number : ADP008046

Title :   Mosaic Reflectivity of X-Ray Multilayer Structures,

Corporate Author : DANISH SPACE RESEARCH INST LYNGBY

Personal Author(s) : Christensen, F.E. ; Schnopper, H.W.

Report Date : 05 MAR 1992

Pagination or Media Count : 3

Abstract : Mosaic reflectivity from multilayer structures has previously been detected but only in a limited angular range close to the Bragg angle (theta B) and only at a single energy. In this paper, a systematic study of the mosaic reflectivity is performed at five line energies (B-K alpha (0. 183 keV), Cr-L alpha (0.573 keV), Ni-L alpha (0.852 keV), Pd-L alpha (2.838 keV), Cu-K alpha (8.048 keV)) for a series of Ni/C multilayers with similar d-spacings and similar ratio between Ni-content and C-content but different deposition methods. The mosaic reflectivity is measured in the complete angular range from zero to 2 theta B around the first order Bragg peak. Several interesting and novel effects are revealed. First of all, it is observed that the mosaic reflectivity increases linearly as the angle of incidence is decreased. Secondly, the mosaic reflectivity is observed to decrease sharply as one enters the total reflection region. Thirdly, the mosaic reflectivity disappears completely as the angle of incidence approaches twice the Bragg angle. Finally, the mosaic reflectivity varies in a characteristic way with the energy.

Descriptors :   *BRAGG ANGLE, *REFLECTIVITY, *STRUCTURES, *X RAYS, *MOSAICS(LIGHT SENSITIVE), ANGLE OF INCIDENCE, ANGLES, APPROACH, DEPOSITION, ENERGY, RATIOS, REFLECTION, REGIONS, NICKEL, CARBON, SPECULAR REFLECTION, LINEAR SYSTEMS, DETECTORS, RESOLUTION.

Subject Categories : Optics
      Physical Chemistry
      Nuclear Physics & Elementary Particle Physics
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE