Elliptical x-ray microprobe mirrors by differential deposition

A differential coating method is described for fabricating high-performance x-ray microfocusing mirrors. With this method, the figure of ultrasmooth s pherical mirrors can be modified to produce elliptical surfaces with low ro ughness and low figure errors. Submicron focusing is demonstrated with prot otype mirrors. The differential deposition method creates stiff monolithic mirrors which are compact, robust, and easy to cool and align. Prototype mi rrors have demonstrated gains of more than 10(4) in beam intensity while ma intaining submilliradian divergence on the sample. This method of producing elliptical mirrors is well matched to the requirements of an x-ray microdi ffraction Kirkpatrick-Baez focusing system. (C) 2000 American Institute of Physics. [S0034-6748(00)01607-5].