Microtec Nord 2026

In his presentation entitled ‘When fractions of an atom make the difference: MEMS actuators for high-finesse resonators in quantum computing’, Paul Raschdorf provides insights into the latest developments in piezoelectrically driven quasi-static MEMS actuators for optical resonators.

The focus is on recent experimental results concerning the mechanical characterisation of the MEMS systems. For the first time, it is demonstrated that the mirror position can be adjusted in a controlled manner within a range of a few picometres, thereby fulfilling a key requirement for the stable coupling of high-finesse optical cavities.

Furthermore, the measurements demonstrate fast, reproducible movements of the mirror surface in the MHz range, thereby opening up a previously hard-to-access operating range for precise yet dynamic cavity stabilisation.

The results presented illustrate how MEMS actuators can be specifically adapted to the requirements of quantum optical systems and which physical limits become relevant in this context.

In his presentation entitled “Aluminium-Filled Through-Glass Vias (TGV): From Concept to Application”, Nils Burmeister will outline the innovative further development of TGV technology.

To date, there are several competing technologies for producing electrically conductive vias in wafer substrates, most of which are based on the use of solder or electroplated copper. These processes require an additional bonding agent layer, which makes the production process more complex and limits the range of possible applications. These methods are particularly problematic for high-frequency applications due to the so-called skin effect. As frequency increases, the electric current becomes concentrated at the surface, leading to undesirable losses in materials with low electrical conductivity, such as bonding agents.

This is where the aluminium TGVs developed by Fraunhofer ISIT come into play. These involve the pressure-filling of glass feedthroughs with molten aluminium. This innovative technology enables through-holes in dielectric substrates to be filled with aluminium – and this is possible for a variety of geometries, such as hole diameter, flank angle, channel inclination and channel length.