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A micromachined thermal emitter for fast transient temperature operation with a novel hot-plate concept is presented. This concept is based on a nonaxis-symmetric design with excellent mechanical properties during temperature modulation combined with high thermal decoupling. Especially, the mechanical stress induced by the thermal expansion of the hot-plate and their suspension was improved. This results in a reduced sensitivity for buckling of the hot-plate. The thermal emitter is fabricated using silicon on insulator (SOI) technology and KOH-etching. Different suspension structures were realized and mechanical and thermal characterizations were performed. Besides the realization of the new hot-plate suspension design, a high thermal emission at wavelengths 5 m has been achieved using ceramic coatings for emissivity enhancement. This kind of emission tuning owns-in contrast to the typical surface and bulk structuring methods-the possibility to act simultaneously as a heater passivation.

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Stand-off and extractive explosive detection methods for short distances are investigated using mid-infrared laser spectroscopy. A quantum cascade laser (QCL) system for TATP-detection by open path absorption spectroscopy in the gas phase was developed. In laboratory measurements a detection limit of 5 ppm*m was achieved. For explosives with lower vapor pressure an extractive hollow fiber based measurement system was investigated. By thermal desorption gaseous TATP or TNT is introduced into a heated fiber. The small sample volume and a fast gas exchange rate enable fast detection. TNT and TATP detection levels below 100 ng are feasible even in samples with a realistic contaminant background

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