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The physical limitations of miniaturization of the traditional silicon-based electronic devices have motivated growing interest in molecular electronics due to its promising potential in transcending Moore's Law. Since the concept of molecular rectifier was first proposed by Ratner and Aviram in 1974, a lot of efforts have been devoted to realizing nondestructive electrical contacts to the individual or ensemble molecules, such as liquid metal contact, break junctions, cross wire junctions, etc. Among them, rolled-up nanotechnology is compatible with the conventional photolithography processes and can provide an efficient strategy to fabricate fully integrated functional molecular devices on a chip via an array of damage-free soft contacts. This nanotechnology takes an important step towards implementing the miniaturization of molecular devices and promotes the development of molecular electronics. In this doctoral thesis, rolled-up nanotechnology is employed to develop functional molecular devices on chips. Enabled by these rolled-up soft contacts, fully integrated molecular rectifiers based on ultrathin molecular heterojunctions are developed for the first time, and they are able to convert alternating current to direct current with frequencies up to 10 MHz. This is also the first time that a nanoscale organic rectifier with an operating frequency exceeding 1 MHz has been fabricated. The remarkable unidirectional current behavior of the molecular devices mainly originates from the intrinsically different surfaces of bottom planar and top microtubular gold electrodes. While the excellent high-frequency response is guaranteed by the charge accumulation in the phthalocyanine molecular heterojunction, which not only improves the charge injection but also increases the carrier density. Then this rolled-up nanotechnology is further employed to explore multi-functional molecular devices. In this thesis, fully integrated process-programmable molecular devices are achieved for the first time, which can switch between photomultiplication photodiodes and bipolar memristors. The transition depends on the release of mobile ions initially stored in the bottom polymeric electrode and can be controlled by modulating the local electric field at the interface between the ultrathin molecular layer and the bottom electrode. Photogenerated-carrier trapping at a low interfacial electric field leads to photomultiplication with an ultrahigh external quantum efficiency (up to 104%). In contrast, mobile-ion polarization triggered by a high interfacial electric field results in ferroelectric-like memristive behaviour with both remarkable resistive on/off ratios and rectification ratios. The combination of the “soft-contact” enabled by rolled-up nanotechnology and the “ion reservoir” provided by the polymeric electrode opens up a novel strategy for integrating multi-functional molecular devices based on the synergistic electronic-ionic reaction to various stimuli.:List of abbreviations 6 Chapter 1 Introduction 8 1.1 Molecular electronics: a brief history 8 1.2 Motivation: why molecular electronics? 9 1.3 Objectives: developing integrated functional molecular devices 14 1.4 Dissertation structure 15 Chapter 2 Fabrication and characterization methods 17 2.1 Core nanotechnology adopted in this thesis: rolled-up nanomembrane contacts 17 2.2 Fabrications 18 2.2.1 Photolithography 18 2.2.2 Spin-coating 23 2.2.3 Electron-beam deposition 24 2.2.4 Sputter deposition 25 2.2.5 Atomic layer deposition 27 2.2.6 Low-temperature evaporation 28 2.3 Characterizations 30 2.3.1 Atomic force microscopy 30 2.3.2 Photoelectron spectroscopy 32 2.3.3 X-ray diffraction 35 Chapter 3 Integrated molecular rectifiers 37 3.1 Introduction 37 3.2 Construction of the organic heterojunction 39 3.3 Microfabrication of the molecular diode 46 3.4 Origination of the rectification 54 3.5 Frequency performance 61 3.6 Discussion 63 Chapter 4 Integrated process-programmable molecular devices 66 4.1 Introduction 66 4.2 Design and microfabrication of the molecular devices 69 4.2.1 Top tubular metallic electrodes 69 4.2.2 Bottom finger polymer electrodes 71 4.3 Function I: Molecular photomultiplication photodiodes 75 4.3.1 Traditional photodiodes and photomultiplication photodiodes 75 4.3.2 Performance of molecular photomultiplication photodiodes 78 4.3.3 Transition voltage spectroscopy 84 4.4 Function II: Molecular bipolar memristors 86 4.4.1 Ion doping-assisted injection 86 4.4.2 Performance of the molecular bipolar memristors 88 4.4.3 Mechanism of the resistance switching 97 4.5 Mechanism of the electric-field-driven transition 106 4.6 Conclusions 108 Chapter 5 Conclusions and outlook 110 5.1 Conclusions 110 5.1.1 Fully integrated molecular rectifiers 110 5.1.2 Fully integrated process-programmable molecular devices 111 5.2 Outlook 111 5.2.1 Improve the yield of the integrated molecular devices 111 5.2.2 Develop integrated molecular functional devices 112 References 113 List of figures and tables 129 Selbständigkeitserklärung 134 Theses 135 Acknowledgments 138 Research achievements 140 Curriculum-vitae 142

Biochip technology is highly effective method that allows monitoring of biomaterials e.g., yeast and bacteria at a time in computerized automatic operations. Miniaturized nanostructure p-n junction test sites, which are arranged on a solid substrate, are proposed to sense and count the biomaterials. This PhD thesis reports on the impedance of p-n junction-based Si biochips with gold ring top electrodes and unstructured gold bottom electrodes, which allows for counting target biomaterial in a liquid-filled ring top electrode region. The phosphor and boron implanted biochips prepared in dissimilar annealing and doping conditions have been considered and three different types of top electrodes designed and tested to check the influence of the properties of the top electrode on the biochips to achieve more convenient samples for bio sensing technology. The systematic experiments on p-n junction-based Si biochips fabricated by two different sets of implantation parameters (i.e., biochips PS5 and BS5) are studied and the comparable significant change of impedance characteristics in the biochips in dependence on the number of bacteria suspensions, i.e., Lysinibacillus sphaericus JG-A12, in Deionized water at optical density at 600 nm from OD600 = 4–16 in the electrode ring region is demonstrated. The number of biomaterials and the microscopic images can be linked to the impedance changes of the biochip. The electrical equivalent circuit models for the devices have been proposed by using characterized frequency dependent capacitance and conductance of biochips. While the Nyquist spectrum of the biochips are not compromise on perfect semicircle, combination of constant phase elements with resistor in parallel fashion and series inductor and resistor have been utilized to model the impedance of the biochips. Corresponding parameters i.e., capacitors, resistors and inductors have been extracted from the modeling results and the changes in their values by adding the biomaterials obtained. As the result, the linear relation between the numbers of the biomaterial and the impedance of the biochips has been showed. Furthermore, Deionized water and glucose with yeast (Saccharomyces cerevisiae) at optical density OD600 ranging from 4 to 16 has been put in the ring electrode region of impedance biochips and impedance has been measured in dependence on the added volume (20, 21, 22, 23, 24, 25 µL). Modeled impedance of the biochip reveals a linear relationship between the impedance model parameters and yeast concentration. Presented biochips allow for continuous impedance measurements without interrupting the cultivation of the yeast. A multiparameter fit of the impedance model parameters allows to determine the concentration of yeast cy in the range from cy = 3.3x10^7 to cy = 17x10^7 cells/mL. This work shows that independent on the liquid, DI water or glucose, the change of the impedance model parameters with increasing added volume of the liquid is clearly distinguishable from the change of impedance model parameters with increasing concentration of added yeast in the ring electrode region of the impedance biochips. We also counted bacterial cells of E. coli strain K12 in several-microliter DI water or in several-microliter PBS at the low optical density (OD) range (OD = 0.05–1.08) in contact with the surface of Si-based impedance biochips with ring electrodes by impedance measurements. The multiparameter fit of the impedance data allowed calibration of the impedance data with the concentration cb of the E. coli cells in the range of cb = 0.06 to 1.26 × 10^9 cells/mL. The results showed that for E. coli in DI water and in PBS, the modelled impedance parameters depend linearly on the concentration of cells in the range of cb = 0.06 to 1.26 × 10^9 cells/mL, whereas the OD, which was independently measured with a spectrophotometer, was only linearly dependent on the concentration of the E. coli cells in the range of cb = 0.06 to 0.50 × 10^9 cells/mL. with the help of the newly developed ring electrode structure, the modeled capacitance and resistance parameters of the electrical equivalent circuit describing the p-n junction-based biochips depend linearly on the number of bacteria in the ring top electrode region, which successfully proves the potential performance of p-n junction-based Si biochips in observing the bacterial suspension. The proposed p-n junction-based biochips reveal perspective applications in medicine and biology for diagnosis, monitoring, management, and treatment of diseases.

To calculate the load capacity of gear stages within complex drivetrains under varying external loads, multi-body-systems (MBS) are used to simulate the vibrational behaviour of integral systems. In order to model a flexible hypoid gear stage, methods like the modal reduction of FEM-models were already introduced. However, the modelling of such systems is complex, challenging and sensitive to its discretisation. The co-simulation within a multi-body-system simulation offers the possibility to outsource the calculation of the tooth contact and therefore the reaction forces under consideration of friction. This leads to a simplification and an improvement of the modelling of gear stages in multi-body-systems. The further developed co-simulation module offers a compromise between computational speeds and exact solutions. To improve the quality of the results and reduce the calculation time the load distribution calculation is investigated specifically. The article describes a method to reduce fluctuations of computed reaction forces and moments during gear movement. The aim is to keep the level of fluctuations of a high contact zone discretisation with a significant smaller contact point count. / Um die Belastbarkeit von Getriebestufen innerhalb komplexer Antriebsstränge unter variierenden äußeren Lasten zu berechnen, werden Mehrkörpersysteme (MKS) zur Simulation des Schwingungsverhaltens von integralen Systemen eingesetzt. Um eine flexible Getriebestufe mit Kegel- oder Hypoidradsätzen zu modellieren, wurden bereits Methoden wie die modale Reduktion von FEM-Modellen eingeführt. Die Modellierung solcher Systeme ist jedoch komplex, anspruchsvoll und empfindlich gegenüber ihrer Diskretisierung. Die Co-Simulation innerhalb einer Mehrkörpersystem-Simulation bietet die Möglichkeit, die Berechnung des Zahnkontakts und damit der Reaktionskräfte unter Berücksichtigung der Reibung auszulagern. Dies führt zu einer Vereinfachung und Verbesserung der Modellierung von Getriebestufen in Mehrkörpersystemen. Das weiterentwickelte Co-Simulations-Modul bietet einen Kompromiss zwischen Berechnungsgeschwindigkeit und exakten Lösungen. Um die Qualität der Ergebnisse zu verbessern und die Berechnungsgeschwindigkeit zu erhöhen, wurde die Berechnung der Lastverteilung untersucht. Der Artikel beschreibt eine Methode zur Reduzierung von Schwankungen der berechneten Kräfte und Momente über der Eingriffsstrecke. Ziel ist es, die Schwankungen auf dem Level einer hohen Kontaktzonendiskretisierung mit einer deutlich geringeren Kontaktpunktanzahl zu halten.

Antibiotic resistance is a global health threat and consequently, there is a need to understand the mechanisms driving its emergence. Here, we hypothesize that genes and mutations under positive selection may contribute to antibiotic resistance. We explored wastewater E. coli, whose genomes are highly diverse. We subjected 92 genomes to a statistical analysis for positively selected genes. We obtained 75 genes under positive selection and explored their potential for antibiotic resistance. We found that eight genes have functions relating to antibiotic resistance, such as biofilm formation, membrane permeability, and bacterial persistence. Finally, we correlated the presence/absence of non-synonymous mutations in positively selected sites of the genes with a function in resistance against 20 most prescribed antibiotics. We identified mutations associated with antibiotic resistance in two genes: the porin ompC and the bacterial persistence gene hipA. These mutations are located at the surface of the proteins and may hence have a direct effect on structure and function. For hipA, we hypothesize that the mutations influence its interaction with hipB and that they enhance the capacity for dormancy as a strategy to evade antibiotics. Overall, genomic data and positive selection analyses uncover novel insights into mechanisms driving antibiotic resistance.

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Polymer brush patterns were prepared by a combination of electron beam induced damage in self-assembled monolayers (SAMs), creating a stable carbonaceous deposit, and consecutive self-initiated photografting and photopolymerization (SIPGP). This newly applied technique, reactive writing (RW), is investigated with 1H,1H,2H,2H-perfluorooctyltriethoxysilane SAM (PF-SAM) on silicon oxide, which, when modified by RW, can be selectively functionalized by SIPGP. With the monomer N,N-dimethylaminoethyl methacrylate (DMAEMA), we demonstrate the straightforward formation of polymer brush gradients and single polymer lines of sub-100 nm lateral dimensions, with high contrast to the PF-SAM background. The lithography parameters acceleration voltage, irradiation dose, beam current and dwell time were systematically varied to identify the optimal conditions for the maximum conversion of the SAM into a carbonaceous deposit. The results of this approach were compared to patterns prepared by carbon templating (CT) under analogous conditions, revealing a dwell time dependency, which differs from earlier reports. This new technique expands the range of CT by giving the opportunity to not only vary the chemistry of the created polymer patterns with monomer choice but also vary the chemistry of the surrounding substrate.

Für die effiziente Blechtafelbearbeitung mit hoher Prozesssicherheit und Teilequalität ist die positions- und winkelgenaue Ausrichtung der Rohblechtafeln vor dem Bearbeitungsprozess erforderlich. Dieser Beitrag untersucht vibrationsbasierte Ausrichtkonzepte mittels Mehrkörpersystem-Simulation. Die entwickelten Simulationsmodelle ermöglichen die Charakterisierung und den Vergleich der Konzepte hinsichtlich der Bewegungs- und Ausrichteigenschaften sowie der erforderlichen Antriebskraft. / Efficient, reliable, and qualitative sheet metal processing requires both positional and angular alignment of the raw metal sheets prior to the manufacturing process. This paper investigates different vibration-based alignment concepts using a multi-body system simulation. The simulation model is then used to characterize and compare, with respect to the motion and alignment properties as well as the required driving force, the diverse vibration-based alignment concepts.

Diese Broschüre stellt alle Maßnahmen zur Förderung der Feuerwehren im Freistaat Sachsen vor. Redaktionsschluss: 31.05.2021