Advances in fabrication of X-ray waveguides

This paper reports on the fabrication of X-ray waveguides, manufactured by e-beam lithography, reactive ion etching and wafer bonding techniques. By combination of these processing steps, long empty (air) channels with cross-sections in the range of 10 to 100nm are obtained, forming a guiding layer, surrounded by a solid state cladding. Aside from silicon, we present also waveguide channels fabricated in germanium and quartz. The improved fabrication protocols lead to significantly enhanced exit flux for imaging applications. Finally, we address not only straight channels, but a large variety of various geometries, as required for different applications. Display Omitted X-ray waveguides were fabricated by e-beam lithography, reactive ion etching and wafer bonding techniquesThe fabrication process was optimized for Si, leading to an enhanced optical performance and then transferred to Ge and SiO2A variety of channel geometries was realized such as straight and curved channels, gratings, beamsplitters

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