Selected Publications
Stretchable electronics (i.e., hybrid inorganic or organic circuits integrated on elastomeric substrates) rely on elastic wiring. We present a technique for fabricating reversibly stretchable metallic films by printing silver-based ink onto microstructured silicone substrates. The wetting and pinning of the ink on the elastomer surface is adjusted and optimized by varying the geometry of micropillar arrays patterned on the silicone substrate. The resulting films exhibit high electrical conductivity (!11 000 S/cm) and can stretch reversibly to 20% strain over 1000 times without failing electrically. The stretchability of the g200 nm thick metallic !lm relies on engineered strain relief in the printed !lm on patterned PDMS.
Chemical Solution Deposition (CSD) is a promising process for industrial long length production of high temperature superconducting tapes because of its low-cost, high-speed production and good scalability. YBa2Cu3O7-x (YBCO) coated conductors are the favourable material with excellent superconducting properties including sufficient high Jc-performance. Nevertheless, the alternating current (ac)-losses are still too high for applications of wires in motors. A special plotting technique allows a printing of filamented structures of YBCO thin layers. The hysteresis losses in such striped films are much lower than in continuously coated substrates with a homogeneous YBCO layer.
Lines as well as rectangular shaped YBCO-structures were deposited by an ink plotting system on single crystal substrates. Different inks were tested, among them an environmentally friendly, water-based fluorine-free YBCO precursor solution as well as an ink, synthesised according to the TFA route.