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Multilayer Laue lenses (MLLs) capitalize on the developments in multilayer deposition technologies for fabricating reflective coatings, specifically undertaken for EUV lithography, where layer thicknesses of several nanometers can be achieved. MLLs are deposited layer by layer, with their thicknesses following the zone plate law, and then pieces are sliced and extracted for use in focusing. Rays are reflected in the Laue geometry. The efficiency of a MLL can be very high, and is maximized by making the slice equal to about a half Pendellosung period so that most energy is transferred from the undiffracted to the diffracted beam, and by ensuring that the Bragg condition is met at each point in the zone plate. This latter condition requires that the layers are tilted to the beam by an amount that varies with layer position; e.g. for focusing a collimated beam, the layers should be normal to a cylinder of radius of twice the focal length. We have fabricated such tilted-zone MLLs and find that they exhibit improved efficiency across their entire pupil as compared with parallel-zone MLLs. This leads to a higher effective NA of the optic and hence higher resolution. [ABSTRACT FROM AUTHOR]

The ablation efficiency of organic polymers (polymethylmethacrylate - PMMA, polytetrafluoroethylene PTFE, polyethyleneterephtalate - PET, and polyimide - PI) and elemental solids (aluminum and silicon) by single pulses of extreme ultraviolet (XUV) radiation emitted from Z-pinch, plasma-focus, and laser-produced plasmas was investigated. The ablation characteristics measured for these plasma-based sources will be compared with those obtained for irradiation of samples with XUV radiation generated by a free-electron laser (FEL). The Z-pinch was driven by the S-300 pulsed-power machine (Kurchatov lnstitute, Moscow) and the plasma focus was realized in the PF-1000 machine (Institute of Plasma Physics and Laser Microfusion, Warsaw). Higher temperature plasma than with the discharge plasmas was obtained by focusing the near-infrared (fundamental frequency) beam from the PALS high-power iodine laser system (Czech Academy of Sciences, Prague) on the surface of a metallic slab target or into single- and double-gas-puff target placed in a vacuum interaction chamber. Much softer (λ = 86 nm), but monochromatic and more intense, radiation is provided in many (repetition rate= 1 Hz) short pulses by the SASE-FEL at the Tesla Test Facility (DESY-HASYLAB, Hamburg). The role of nonthermal processes in XUV ablation will be evaluated. Mechanisms based on the nonthermal processes will be proposed. [ABSTRACT FROM AUTHOR]