Printing on particles: combining two-photon nanolithography and capillary assembly to fabricate multi-material microstructures

Steven van Kesteren; Xueting Shen; Michele Aldeghi; Lucio Isa

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arXiv · 2208.02635

Printing on particles: combining two-photon nanolithography and capillary assembly to fabricate multi-material microstructures

Steven van Kesteren·Xueting Shen·Michele Aldeghi·Lucio Isa

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Abstract

Additive manufacturing at the micro- and nanoscale has seen a recent upsurge to suit the increasing demand for more elaborate structures. However, the integration and precise placement of multiple distinct materials at small scales remain a challenge. To this end, we combine here the directed capillary assembly of colloidal particles and two-photon direct laser writing (DLW) to realize a new class of multi-material microstructures. We use DLW both to fabricate 3D micro-templates to guide the capillary assembly of soft- and hard colloids, and to link well-defined arrangements of polystyrene or silica particles produced with capillary assembly, a process we term "printing on particles". The printing process is based on automated particle recognition algorithms and enables the user to connect colloids into one- and two-dimensional tailored structures, including particle clusters and lattices of varying symmetry and composition, using commercial photo-resists (IP-L or IP-PDMS). Once printed and developed, the structures can be easily harvested and re-dispersed in water. The flexibility of our method allows the combination of a wide range of materials into complex structures, which we envisage will boost the realization of new systems for a broad range of fields, including microrobotics, micromanipulation and metamaterials.

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Steven van Kesteren, Xueting Shen, Michele Aldeghi, Lucio Isa. 2022-08-04. Printing on particles: combining two-photon nanolithography and capillary assembly to fabricate multi-material microstructures. https://arxiv.org/abs/2208.02635

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