Generation of high-contrast "Talbot carpets" with the use of a mesoscale amplitude-phase mask
Yu.E. Geints1, A.A. Zemlyanov1, E.K. Panina1, I.V. Minin2,3, O.V. Minin2,3
1V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
2Research Tomsk Polytechnic University, Tomsk, Russia
3Siberian State University of Geosystems and Technologies, Novosibirsk, Russia
Keywords: эффект Талбота, фотолитография, дифракционные маски, Talbot effect, photolithography, diffraction mask
Abstract
The spatial near-field structure of optical wave scattered by a composite amplitude-phase diffraction mask with a ruling period on a wavelength scale is studied in numerical simulations by the finite element method. As applied to the displacement Talbot-nanolithography, such a combined binary mask is shown to provide multiple enhancement of the optical contrast of an integral "Talbot carpet" as compared to pure amplitude and phase masks. The physical causes of this effect are analyzed and the key role of Mie resonances excited inside the dielectric bars of the phase mask is ascertained. Meanwhile, the combined mask suggested ensures a high spatial resolution (up to a quarter of optical wavelength) and maximal optical contrast (up to 24 dB) of integral Talbot's self-images.
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