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Thin film capacitors were fabricated by sputtering TiN-Y doped HfO2-TiN stacks on silicon substrates. Yttrium was incorporated into the HfO2 layers by simultaneously sputtering from Y2O3 and HfO2 sources. Electric polarization and relative permittivity measurements yield distinct ferroelectric properties as a result of low yttrium dopant concentrations in the range of 0.9-1.9 mol. %. Grazing incidence x-ray diffraction measurements show the formation of an orthorhombic phase in this range. Compared to atomic layer deposition films, the highest remanent polarization and the highest relative permittivity were obtained at significantly lower doping concentrations in these sputtered films

A three-pronged approach has been used to design rational improvements in self-assembled monolayer field-effect transistors: classical molecular dynamics (MD) simulations to investigate atomistic structure, large-scale quantum mechanical (QM) calculations for electronic properties, and device fabrication and characterization as the ultimate goal. The MD simulations reveal the effect of using two-component monolayers to achieve intact dielectric insulating layers and a well-defined semiconductor channel. The QM calculations identify improved conduction paths in the monolayers that consist of an optimum mixing ratio of the components. These results have been used both to confirm the predictions of the calculations and to optimize real devices. Monolayers were characterized with X-ray reflectivity measurements and by electronic characterization of complete devices.

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In the present study the cellular uptake of targeted immunoliposomes by interleukin-1 activated human endothelial cells has been analysed by several spectroscopical and microscopical fluorescence techniques. Previous in vitro experiments demonstrated that the targeting of immunoliposomes to vascular selectins is a potential way for a selective drug delivery at inflammatory sites. In attempts to further adapt the targeting experiments to physiological conditions, we demonstrate that E-Selectin-directed immunoliposomes are able to bind their target cells under the simulated shear force conditions of capillary blood flow cumulatively for up to 18 h. In order to consequently follow the fate of liposomes after target binding, we analysed the route and degree of liposome internalization of the cells concentrating on cell activation state or various liposomal parameters, e.g., sterical stabilization, type of antibody or antibody coupling strategy. The use of NBD-labelled liposomes and subsequent fluorescence quenching outside the cells with dithionite show that circa 25% of the targeted immunoliposomes were internalized. According to inhibition experiments with agents that interfered with the endocytotic pathway, we found out that the major mechanism of liposome entry is endocytic. The entry involves, at least in part, receptor-mediated endocytosis via E-Selectin, a liposome accumulation in the endosomes and their acidification was proved by pyranine spectroscopic results. Furthermore, microscopical investigations demonstrate that also a fusion of liposomes with the cell membrane occurs followed by a release of entrapped calcein into the cytoplasm. These observations gain insight into the behaviour of E-Selectin-targeted immunoliposomes and indicate that these immunoliposomes have great potential to be used as drug carriers for intracellular drug delivery at inflammatory sites.

Silicon anodes offer a very promising approach to boost the energy density of lithium-ion batteries. While silicon anodes show a high capacity and, depending on the system, a good cycle stability in half-cells vs lithium, their integration in industrially applicable lithium-ion full-cells is still challenging. Balancing described as the capacity ratio of negative and positive electrode (n/p ratio) is a crucial necessity for the successful design of lithium-ion batteries. In this work, three different silicon based anode systems, namely carbon coated silicon nanowires, columnar silicon thin films and silicon-carbon void structures are compared in LIB full cells containing NMC111 cathodes. By varying the areal capacity of the NMC111 cathode, the influence of the balancing was investigated over a broad n/p range of 0.8−3.2. The aim was to find an ideal compromise between lithium plating suppression, high cycling stability and maximized energy density. To underline the high volumetric energy density, the columnar silicon thin films are additionally analyzed in multilayered pouch cells with NMC622 and NMC811 cathodes resulting in 605 Wh L−1 and 135 Wh kg−1 and even 806 Wh L−1 and 183 Wh kg−1 as demonstrated on stack level.