This paper describes the first thermoelectric devices based on the V-VI-compounds Bi/sub 2/Te/sub 3/ and (Bi,Sb)/sub 2/Te/sub 3/ which can be manufactured by means of regular thin film technology in combination with microsystem technology. Fabrication concept, material deposition for some 10-/spl mu/m-thick layers and the properties of the deposited thermoelectric materials will be reported. First device properties for Peltier-coolers and thermogenerators will be shown as well as investigations on long term and cycling stability. Data on metal/semiconductor contact resistance were extracted form device data. Device characteristics like response time for a Peltier-cooler and power output for a thermogenerator will be compared to commercial devices

No abstract

The effect of humidity on chromium titanium oxide (Cr/sub 2-x/Ti/sub x/O/sub 3+z/, CTO), on both baseline resistance and sensitivity, is small compared to SnO/sub 2/. This has been the key to development of thick-film sensors based on CTO, for detection of carbon monoxide and ammonia in synthetic air. Thin-film structures on silicon substrates offer the possibility to use fabricating, bonding and housing equipment and, hence, a low cost gas sensor production is possible. CTO thin-film sensors on silicon substrates use conventional photolithography, sputtering and evaporation techniques. A Ta/Pt resistance layer (25/200- nm thick) for heating the device to its operating temperature and interdigital electrodes are evaporated and structured on a silicon substrate which is covered by a 1- mu m SiO/sub 2/ insulating layer. The polycrystalline p-type CTO is deposited onto the electrodes by oxidizing reactive sputtering or evaporation of Cr/Ti-sandwich structures. The resulting sensors were characterized by means of energy dispersive X-ray analysis, secondary electron microscopy, and X-ray diffraction pattern. Also, gas responses toward NO/sub 2/, NH/sub 3/, CO and CH/sub 4/, and different humidity, were investigated

No abstract