Surface roughness of stainless-steel mirrors for focusing soft x rays
Abstract
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.
- Publication:
-
Applied Optics
- Pub Date:
- July 2006
- DOI:
- 10.1364/AO.45.004833
- Bibcode:
- 2006ApOpt..45.4833Y
- Keywords:
-
- Surface measurements;
- roughness;
- Optomechanics;
- Polishing;
- Roughness;
- X-ray mirrors