High rotational symmetry photonic structures fabricated with multiple exposure Displacement Talbot Lithography

•Displacement Talbot Lithography used for generating quasi periodic structures•Superposition of periodic structures lead to quasi periodic structures•Resulting structure can be considered as a Moiré pattern•Method suitable for efficient fabrication of wafer-scale quasi-periodic patterns•Useful for applications requiring isotropic photonic response

Quasi-periodic structures with a high degree of rotational symmetry are desired for photonic applications because of their nearly isotropic optical response, in contrast to the highly directional behavior of periodic lattices. Here we introduce a method based on the superposition of periodic structures obtained by multiple exposure of a photomask with Displacement Talbot Lithography in which the photomask is rotated by a certain angle between exposures. The resulting structure can be considered as a Moiré pattern. High-quality patterns with 10 and 12-fold rotation symmetries and resolutions in the sub-micron to micron range are uniformly and reproducibly printed. The technique is suitable for the mass fabrication of wafer-scale quasi-periodic photonic patterns.

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