Clean Room

B. Menges

The clean room Class 100 is a service laboratory for micro and nano structuring as well as for sample preparation under particularly dust free conditions. For the preparation of ultrathin layers or supra molecular architectures different techniques are available a Langmuir trough or a spin coater. Micro and nano structuring of polymer or inorganic materials can be done by established techniques such as optical lithography and reactive ion beam etching (RIBE). The infrastructure allows for complex preparation of integrated optics and sensors including specific surface functionalizations.

left : Micromachined optical device for thermal detection via thin film resistor of surface plasmon resonance excited by a shallow diffraction grating. right : Thermal simulation of sensor membrane with finite element method

Another example are the microstructures for controlled growth of neurons. The cultivation of neuronal networks on multielectrode array (MEA) chips allows for extra cellular recordings by electrical activity from a multitude of recording sites simultaneously. Stamps made of polydimethylsiloxane are cast from microstructures shaped in photoresist. By these stamps a triangular protein pattern is transferred to the MEA surface so that its geometry matches that of the electrode arrangement. Neurons seeded onto this modified chip surface preferably settle at the nodes of the pattern and expand their neurities along the 4-6 µm thin lines. Following cultivation for 3 weeks, vital and functional micro patterned networks have been developed from which electrical activity can be recorded for several weeks.

left : Microstructure for controlled growth of neuron. right : Neurons after 3 weeks in vitro growing in a triangular pattern on a MEA. Electrodes and conducting paths appear in black.

M. Jungblut, M. Pottek, C. Schwind, W. Knoll, C. Thielemann. Micropatterned neuronal networks on microelectrode arrays. Proceedings of 4th International Meeting on substrate-integrated Microelectrode Arrays, Reutlingen, 2004, p.65.
V. Jacobsen, B. Menges, S. Mittler, R. Förch, W. Knoll. In-situ thin film diagnostics using waveguide mode spectroscopy, Thin Solid Films 409, 2002, 185-193