Ion beam lithography for Fresnel zone plates in X-ray microscopy

Abstract

Fresnel Zone Plates (FZP) are to date very successful focusing optics for X-rays. Established methods of fabrication are rather complex and based on electron beam lithography (EBL). Here, we show that ion beam lithography (IBL) may advantageously simplify their preparation. A FZP operable from the extreme UV to the limit of the hard X-ray was prepared and tested from 450 eV to 1500 eV. The trapezoidal profile of the FZP favorably activates its 2 nd order focus. The FZP with an outermost zone width of 100 nm allows the visualization of features down to 61, 31 and 21 nm in the 1 st , 2 nd and 3 rd order focus respectively. Measured efficiencies in the 1 st and 2 nd order of diffraction reach the theoretical predictions. References and links1. D. T. Attwood, Soft X-rays and extreme ultraviolet radiation (Cambridge University Press, 1999). 2. A. Sakdinawat and D. Attwood, "Nanoscale X-ray imaging," Nature Photonics 4, 840-848 (2010). 3. R. Falcone, C. Jacobsen, J. Kirz, S. Marchesini, D. Shapiro, and J. Spence, "New directions in X-ray microscopy," Contemp. Phys. 52, 293-318 (2011). 4. B. Kaulich, P. Thibault, A. Gianoncelli, and M. Kiskinova, "Transmission and emission x-ray microscopy: operation modes, contrast mechanisms and applications," J. (12) in this article (equation (13) and (14)

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