Eberhard Spiller
Nuclear Inst. and Methods in Physics Research, A
Scattering of the multilayer coatings used for our normal incidence soft x-ray telescope at λ=63.5 Å has been measured at λ=1.54 Å and grazing angles of incidence and at soft x rays near normal incidence. Furthermore, the edge of the moon is used as a known test target to estimate the amount of scattering in the arcsec range from images obtained on the date of the solar eclipse on July 11, 1991. The internal surfaces of the coating are inspected by high-resolution electron microscopy. A theoretical model describing the evolution and replication of roughness from layer to layer throughout the structure, which is in agreement with all experimental data is presented. We find that practically all roughness caused by the growth of the multilayer structure occurs at spatial frequencies which are too high to produce scattering. The substrate roughness is replicated at lower spatial frequencies which might produce scattering within the field of view of an instrument. However, roughness in this range is below the 0.5 Å level again resulting in insignificant amounts of scatter.
Eberhard Spiller
Nuclear Inst. and Methods in Physics Research, A
Eberhard Spiller
Optics in Complex Systems 1990
Ivan Haller, Ralph Feder, et al.
JES
Eberhard Spiller
Journal of Applied Physics