| The unique properties of shape memory alloy (SMA) films, such as highest work densities up to 107 J/m³ and favorable down-scaling of actuation performance, provide a basis for the development of novel cooperative and multistable microactuator systems with intrinsic sensing capability for the smart control of processes at the nanoscale, especially if the relative high energy consumption can be significantly reduced by bi/multistability. So far, the vast majority of actuators for nanomechanical / nanophotonic switching and tuning is based on electrostatics, using either comb-drive or gap closing actuators. Current actuator concepts have in common that they require rather a large footprint exceeding 100 x 100 µm² in many cases, which results from limited effect size due to poor down-scaling. These limitations may be overcome by introducing nanoactuators based on SMA films. The high miniaturization potential is underlined, e.g. by the recent demonstration of an ultra-compact nanophotonic switch having a footprint of only 1 x 1 µm². Therefore, this proposal aims at the development and experimental as well as simulation-based investigation of novel cooperative bistable and multistable SMA-polymer microactuator systems and their combination with silicon nanotechnology for switching and tuning of nanometer-scale silicon devices. Major challenges are the control of coordinated bi- and multistable actuation with ultra-high precision in the order of 100 nm required for the nanophotonic application scenario, mastering the various electro-thermo-mechanical coupling effects resulting from material properties, engineering and system constraints and the significant computational effort due to a high number of simulations being needed for the development and the characterization. Piezoelectric stress sensing will be introduced to monitor phase transformation and thus to sense relative position. A monolithic fabrication technology is required to achieve a high integration density.In order to address these interdisciplinary challenges, the project combines the complementary expertise of coupled simulation (S. Wulfinghoff), thermo-elastic materials science (E. Quandt) and engineering of micro- and nanoscale systems (M. Kohl). |
Professor Dr.-Ing. Stephan Wulfinghoff Christian-Albrechts-Universität zu Kiel Telefon: +49 431 8804321 E-Mail: swu ∂does-not-exist.tf uni-kiel de www.tf.uni-kiel.de/matwis/cms/en
Professor Dr.-Ing. Eckhard Quandt Christian-Albrechts-Universität zu Kiel Telefon: +49 431 8806200 E-Mail: eq ∂does-not-exist.tf uni-kiel de www.tf.uni-kiel.de/matwis/afm/en
Professor Dr. Manfred Kohl Karlsruher Institut für Technologie (KIT) Telefon: +49 721 60822798 |
