Thin polystyrene films ͑prepared in a sandwich geometry between two aluminum electrodes͒ develop a characteristic pattern in ambient air when kept above the glass-transition temperature, whereas they remain unchanged in vacuum or in a pure nitrogen atmosphere. Measurements by broadband dielectric spectroscopy, capacitive dilatometry, and AC calorimetry reveal that the pattern formation is initiated in ambient air by an increase in the average relaxation rate of the dynamic glass transition, which results in a corresponding reduction of the glass-transition temperature. Infrared measurements evidence that this is caused by a shift of the molecular weight distribution to lower values as a consequence of oxygen-induced chain scissions.

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Within the ENIAC project "IMPROVE", new algorithms for virtual metrology and predictive maintenance are being developed to substantially enhance efficiency in European semiconductor manufacturing. The consortium comprises important IC manufacturers in Europe, solution providers, and research institutions. A major objective of the project is to make these new APC methods applicable in the existing fab systems of the IC manufacturers which widely differ in the automation infrastructure. A novel framework architecture for integration of the new control paradigms was researched and a software for implementation of the framework was developed. This paper describes the technical details and results of the framework development, implementation, and test

ZnO has a huge potential and is already a crucial material in a range of key technologies from photovoltaics to opto and printed electronics. ZnO is being characterized by versatile metrologies to reveal electrical, optical, structural and other parameters with the aim of process optimization for best device performance. The aim of the present work is to reveal the capabilities of vacuum ultra-violet (VUV) reflectometry for the characterization of ZnO films of nominally 50 nm, doped by Ga and In. Optical metrologies have already shown to be able to sensitively measure the gap energy, the exciton strength, the density, the surface nanoroughness and a range of technologically important structural and material parameters. It has also been shown that these optical properties closely correlate with the most important electrical properties like the carrier density and hence the specific resistance of the film. We show that VUV reflectometry is a highly sensitive optical method that is capable of the characterization of crucial film properties. Our results have been cross-checked by reference methods such as ellipsometry and X-ray fluorescence.