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Miniaturization and modularization are fast growing fields in chemical engineering in recent years. Fast and flexible production processes for microstructured devices are desirable to meet the requirements of rapid prototyping and flexible chip manufacturing. Reactive ion etching provides a structuring process which leads to a highly precise and anisotropic etching behavior. A new manufacturing process for polyimide-based microstructured devices with low surface roughness was developed and applied on reactor geometry for liquid-liquid two-phase-flow. The fabricated chip geometry is designed for creating droplets via flow focusing as the dispersed phase is incised by two continuous phase inlet streams. The droplets are created in the widening channel. In order to keep the pressure loss for the developed reactor geometry and the production time as small as possible, the manufacturing process was optimized with a view to minimize surface roughness and maximizing the etching rate by using Design of Experiments. The corresponding pressure drop was measured for flow rates from 0.05 ml min−1 to 0.5 ml min−1.

Besides the common benefits of micro-structured reactors such as enhanced mass and heat transfer caused by a high specific surface and enhanced mixing, they have also drawbacks due to their tiny dimensions. Non-invasive temperature measurement is an important issue for micro process engineering regarding to process control and safety issues. High resolution and robustness are requirements which should be met by the temperature measuring method. Thin film technology combines the possibility to manufacture micro scaled structures with great flexibility in choosing material and geometry of the structures. Layers of aluminum with a thickness in nanometer range are deposited on flexible polyimide foil and structured lithographically to obtain electrical conductor tracks which are used as temperature sensors based on their electrical resistance. The produced temperature sensors were calibrated in the range from 20 to 70 °C and the accuracy of the sensors was checked.