The Development of Single and Multilayered Wolter X-ray Microscopes

Abstract

Scanning Wolter X-ray microscopes having resolutions of at least 0.1 pm at wavelengths down to 0.15 nm are being developed. The initial objective of the work is to produce a microscope mirror substrate which will be evaluated and used at 4 nm as a non-multilayered microscope. It will have virtually the same geometry as the mirror which will subsequently be used in multilayered form at much shorter wavelengths. The problems of substrate manufacture to the required tolerances together with the development of the associated specialised metrological instrumentation will be similar for both microscopes. A theoretical study has been undertaken in which the images produced by multilayered mirror systems are calculated by ray tracing, using geometrical diffraction optics and the Debye approximation. Each element of the wavefront is described by a ray carrying the field vectors. An optimisation procedure for calculating the layer structure has been derived. For maximum flux throughput, the variation of the layer structure and roughness must be controlled to about 0.1 nm.© (1985) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.