Stereolithography (SLA) is a widely used technique for the fabrication of prototypes and small series products. The main advantage of SLA and related solid freeform fabrication (SFF) techniques is their capability to fabricate parts with complex shapes with high resolution. Although the spectrum of available materials has been widened in recent years, there is still a lack of materials which can be processed with SLA on a routine basis. In this work, a micro-SLA (μSLA) system is presented which can shape a number of different photopolymers with resolutions down to 5 μm in the xy-plane and 10 μm in the z-direction. The system is capable of processing various specifically tailored photopolymers which are based on acrylate chemistry. The materials processed for this work range from hybrid sol-gel materials (ORMOCER) to photo-crosslinked elastomers and hydrogels. The elastic moduli of these materials can be tuned over several orders of magnitude and range from 0.1 MPa to 8000 MPa. The reactivity of these monomers is sufficient for achieving writing speeds up to 500 mm s −1 which is comparable to commercial SLA resins. Various test structures are presented which show the suitability of the process for fabricating parts required for applications in micro-mechanical systems as well as for applications in biomedical engineering. Using the presented system, internal channels with a diameter of 50 μm and a length of 1500 μm could be fabricated. It was also possible to manufacture a micro-mechanical system consisting of a fixed axe and a free spinning turbine wheel.

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Top down technique of interfering femtosecond laser processing was applied to generate new nanomaterials such as nanocrown, nanomesh, nanobelt, and dual periodic structure. In the case of nanocrown, whiskers are standing at the edge of a nanohole. The width of a whisker was just 80 nm. A nanohole array structure generated by interfering 4 beams was applied to a spatial filter as a base material for the growth of photo-polymerizing polymer, and polymer nanobump array was generated. Dual periodic structures were generated by multiple shots, and bimetallic nanobelt was generated from bilayer thin film. Processing of fiber film was tested.

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Observation of defects inscribed in 3D photonic band gap opal templates has been investigated by means of fluorescence of solidified photo polymer. The defects, or breaks in periodicity, have been inscribed inside the structure by two-photon polymerization (2PP) of an infiltrated hybrid polymer from the type ORMOCER ® . In-situ and ex-situ observation of the inscribed defects has been achieved with fluorescence microscopy.