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Laser direct polymerization has been proven as a powerful tool to generate microstructures. Often photosensitive polymer materials are used because they can be tuned by photoactive molecules to be susceptible to a specific wavelength of light to initiate the polymerization process. One of the main drawbacks of this technique is the lack of functional polymers, e.g. conductive, magnetic, mechanical, optical or bioactive materials. Nanocomposites (nanocompounds), i.e. polymers with inorganic nanomaterials incorporated in the matrix offer a huge variety of new functionalities. A new approach will be presented how functional nanocomposite polymers can be generated and used for laser direct writing techniques. This can open the door for completely new MEMS and MOEMS devices comprising active and passive subcomponents.

The present work reveals the structural and magnetic properties of iron oxide (Fe x O y ) nanoparticles (NPs) prepared by femtosecond laser ablation. The Fe x O y -NPs were produced in solutions consisting of different ratios of water and acetone. Laser ablation in water yields agglomerates and that in acetone yields chain structures whereas that in water/acetone show a mixture of both. We observe significant fabrication dependent properties such as different crystallinities and magnetic behaviors. The structural characterization shows a change from iron (Fe) to a Fe x O y state of the NPs which depends on the solution composition. Furthermore, transmission electron microscopy measurements exhibit a broad particle size distribution in all samples but with significant differences in the mean sizes. Using magnetic measurements we show that nanoparticles fabricated in pure acetone have lower coercive fields which come along with a smaller mean particle size and therefore increasing superparamagnetic behavior.