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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