In this thesis, a 3D CMOS imager based on time-of-flight (TOF) has been developed and successfully tested. It uses an active pulsed class 1 laser operating at 910nm to illuminate a 3D scene. The scene depth is determined by measurement of the travel time of reflected pulses by employing a fast on-chip synchronous shutter. A so-called Multiple Double Short Time Integration (MDSI) enables suppression of the background illumination and correction for reflectivity variations in the scene objects. The sensor chip contains two pixel lines with each pixel containing twin photodiodes, thus the chip contains 4´64 sensors. The chip allows tow operating modes; the first is the binning mode, where the twin pixels are short-circuited (tow lines on the die) and the average signal is measured. The second mode is the high-resolution mode. In this mode the pixels operate separately (four lines on the die). The chip has been realized in 0.5mm n-well standard CMOS process. The pixel pitch is 130mm. To get a good fill factor, the readout circuitry is located at the sides of the chip.

The dissertation describes the effects of operating frequency reduction on the transmission behaviour of power cables. Strongly reduced current losses, lowered induced voltages in the sheaths and lower charging currents offer new solutions for the transmission of energy by cables. The following facts can be obtained by reduction of the operating frequency: an increase of the current carrying capacity, an enlargement of the transmission distance, lower thermal stress of the cable and better efficiency of the power transmission. The above mentioned advantages are typical for direct current transmission systems, but can now also be achieved for usual alternating current cables by reduction of the operating frequency. The positive effects of frequency reduction are represented for different types of power cables. The second part of the thesis describes the transmission behaviour for high frequencies. Travelling electromagnetic waves in power cables are strongly influenced by the frequency- dependent attenuation. For many applications in overvoltage protection the knowledge of the attenuation is very important. Especially in long cable systems the attenuation can be so high that lightning or switching voltages will be reduced to an innocuous level. Another area is the Power Line Communication (PLC) which uses the energy power grid for signal transmission in a frequency range up to 30 MHz. Here an in-depth analysis of the attenuation of the transmission line is very important. Particularly the admittance of the cable, composed of insulating and semiconducting materials, is very important for the attenuation of high frequencies. Simulation results agree well with measurements at a 20-kV-XLPE cable, if the semiconducting layers between conductor and screen are thoroughly modeled. For the calculations, the material parameters of the commonly used carbon-polyethylene-compound and conductive paper layers were measured. Measurements at a test setup show the attenuation for several plies of conducting paper layers on the inner conductor of a coaxial pipe system. The effect of different numbers of plies on the impulse rise time were investigated.

This work describes the fabrication and usability of organic polymeric layers as gate insulators of field effect transistors (reference field effect transistors, REFET) that are dedicated to the determination of pH-reference potentials in electrolytic solutions. Based on the site binding model hydrophobe CF-polymers were investigated. Various techniques are able to generate polymeric layers that are characterized by low selective hydrogen ion sensitivity. Additional results indicate the necessity of reexamination the site binding model´s usability for polymers with low amount of dissociating sites. This work suggests a model assuming ion adsorption onto polymeric surfaces. This model describes results from CV-measurements as well as measurements on REFETs in a qualitative and quantitative way

Molekularstrahlepitaxie, Technologie und Modellierung von InP-basierenden Heterostrukturfeldeffekttransistoren mit reduzierten Stoßionisationsraten und additiven Löcher- und Elektronenbarrieren zur Erzielung kleinster Leckströme und grössten Durchbruchsspannungen bei höchsten Schaltgeschwindigkeiten

In this work optical measurement techniques are developed and performed for the on-wafer and in-circuit characterisation of coplanar HF devices and circuits. Electro-optic sampling methods have been used most commonly deploying the Pockels-effect. It can shown, that also electroabsorptive mechanisms can be used for the measurement of HF signals. In addition, optical heterodyning is applied to transfer the microwave signal that is to detect to lower frequency ranges. - Gegenstand der vorliegenden Dissertation ist die Entwicklung einer optischen Messtechnik, die zur Untersuchung und Charakterisierung von koplanaren Hochfrequenz-Bauelementen und -Schaltungen eingesetzt werden kann. Hervorragende Ergebnisse konnten bislang mit der elektrooptischen Messtechnik erzielt werden, welche den Pockels-Effekt zwischen einem durch das Bauelement propagierenden Mikrowellensignal und einem optischen Abtaststrahl ausnutzt. Die vorliegende Arbeit zeigt, dass auch elektroabsorptive Effekte für optische Messverfahren eingesetzt werden können. Sie präsentiert zudem die Möglichkeit, durch die Heterodyn-Technik, also das geeignete Mischen zweier wellenlängenverstimmter cw-Laser, das Mikrowellensignal in niedrigere und damit einfacher zu messende Frequenzbereiche herunterzutransferieren.

This thesis describes the optimization and characterisation of an integrated fluxgate sensor. It is fabricated with a CMOS-compatible technology for planar coils with ferromagnetic cores. Limitations of sensor measurement range and linearity are analyzed by analytical and numerical calculations of stray fields and demagnetizing effects in the cores coupled with signal analysis of the calculated coil output voltage. The sensor resultion is limited by magnetic domain effects. Based on these results the sensor layout is optimized for the compass application. Electrical and magneto-optical methods for on wafer characterisation of the ferromagnetic layer, the electrical and magnetical coil parameters and the sensor itself are developed and meet production requirements.

A procedure for yield prediction and reliability estimation for microlectronic circuit manufacturing was developed in this thesis. Therefore the interaction between defects distributed randomly and chip layout structures was investigated mainly. At first a new method for the optical defect measurement has been introduced considering the real defect outline which is unavoidable to extract the correct defect size distribution. The simulation tool CALYPSO was created to detect the sensitivity of the layout on defects of various types and sizes. The code benefits from a novel combination of well known simulation principles to reach a very high speed of the numerical runs. Not only yield relevant defects can be considered but latent and build-in reliability defects leading to lifetime shortening too. For this two additional special modules have been implemented. So CALYPSO can not only predict the reachable yield of any microelectronic circuit manufacturing but can also be used for IC lifetime estimation.

The use of the quaternary semiconductor alloy Ga_xIn_1-xAs_yP_1-y for the development of new electronic, optoelectronic or high speed microwave devices is of great technological interest e.g. in telecommunication. Under certain manufacturing conditions unwanted variations in the chemical composition of these materials can occur, which can be attributed to the existence of a miscibility gap. These decomposition phenomena occur within the nanometer and subnanometer scale. Therefore it is necessary to use characterisation methods of high sensitivity and at the same time highest spatial resolution to investigate independently key parameters such as layer thickness, chemical composition or crystalline structure. The Scanning Transmission Electron Microscope (STEM) is suited for such material analyses since it combines illustrating and analytic characterisation methods together with high spatial resolution. The goal of this work was a comprehensive qualitative and quantitativ e investigation of decomposition in GaxIn1-xAsyP1-y using characterisation techniques like bright-field and Z-contrast imaging as well as electron energy loss spectroscopy (EELS) and convergent beam electron diffraction (CBED), performed in a STEM. For the first time the chemical decomposition process were quantified on the nanometer scale. The course of the decomposition and the predicted expansion of the miscibility gap could be acknowledged in the experiment. Additionally it was shown that by optimising growth parameters (e.g. pressure) of strain compensated superlattices the decomposition process could be inhibited or even stopped. At the same time for the improvement of the evaluation of high resolution Z-contrast images the maximum entropy method (MEM) was applied. Due to the use of the MEM the high resolution Z-contrast images permits the investigation of defect structures and for the first time using a STEM at 100 keV the dumb bells of GaSb was resolved in maximum entropy reconstruction

Restoration of electrical power systems after severe disturbances is characterised by high time pressure and low experience of the operating personnel. The thesis describes a flexible approach for training and/or guidance of operators in system restoration, for the first time realised as a generic solution applicable to any given disturbance situation in any power system. Under consideration of the actual states of network and power units the system step by step suggests operational measures to be per-formed. The implementation also comprises components for knowledge acquisition, consistency check and explanation of reasoning; optionally an acoustic user dialogue can be activated. Coupling of the entire system with an operator training simulator gave the opportunity for verification with a large variety of scenarios on different power systems replicated under operational realism.

Nearly 80% of the worldwide semiconductor market volume is covered by standard-CMOS-technology products. Due to the increasing demand on highly flexible, reliable and robust image sensors from many different industry parts, CMOS-technology has become more and more attractive, since it offers several features in contrast to the CCD-technology. The focus of this work lies on the development of high dynamic range CMOS image sensors suitable for industrial, automotive and consumer applications. The developed sensors should yield more powerful and cost-saving system solutions compared with CCD-sensor systems that are available from the market. The work concentrates on mainly linear CMOS-sensors offering a linear dependency between illumination and electronic signal representation. The developed sensors achieve a dynamic range of more than 90dB, which is much more than CCD´s have with 50-60dB. Two sensors are presented with the first one using a mixed logarithmic/linear characteristic and the second sensor working with a multi-illumination scheme using different exposure/integration times, resp. The work finishes with a discussion of the presented sensors and their underlying signal processing algorithms and a short outlook on future developments.