Surface roughness of stainless-steel mirrors for focusing soft x rays.
We have used polished stainless steel as a mirror substrate to provide focusing of soft x rays in grazing-incidence reflection. The critical issue of the quality of the steel surface, polished and coated with gold, is discussed in detail. A comparison is made to a polished, gold-coated, electroless nickel surface, which provides a smoother finish. We used the surface height distributions, measured with an interferometric microscope and complemented by atomic-force microscope measurements, to compute power spectral densities and then to evaluate the surface roughness. The effects of roughness in reducing the specular reflectivity were verified by soft-x-ray measurements.
Yashchuk
Valeriy V
VV
Lawrence Berkeley National Laboratory, Berkeley, California 94720-8199, USA. vvyashchuk@lbl.gov
Gullikson
Eric M
EM
Howells
Malcolm R
MR
Irick
Steve C
SC
MacDowell
Alastair A
AA
McKinney
Wayne R
WR
Salmassi
Farhad
F
Warwick
Tony
T
Metz
James P
JP
Tonnessen
Thomas W
TW