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Superconducting titanium thin films are good candidates for transition edge sensors. In this paper, we deposit titanium thin films on cooled silicon-on-insulator substrates by using electron-beam evaporation. The deposition rate dependence of the film stress, resistivity, and superconducting transition temperature are presented and analyzed. The relationship between film electrical properties and thickness is discussed. For investigating the heating influence on thin Ti films, a depth profile of oxygen diffusion in the films is also analyzed by X-ray photoelectron spectroscopy. [ABSTRACT FROM AUTHOR]

Until recently, our work on superconducting thin film phonon sensors for cryogenic detector applications was limited to silicon substrates only. We have now successfully extended low T/sub c/ (/spl les/100 mK) tungsten sensor technology and sensor fabrication capability to include high purity germanium substrates as well. Here, we describe a technique for fabricating low T/sub c/ superconducting tungsten films on germanium, and we present first results from cryogenic characterization experiments with these films. We also summarize our work on the development of a process to independently etch aluminum and tungsten films deposited on the same germanium substrate. The capability to selectively etch aluminum and tungsten films is critical for the fabrication of our silicon and soon also germanium detectors which utilize overlapping thin films of superconducting tungsten and aluminum for the phonon sensors. Due to the nature of their operation, we refer to these sensors as W/Al Quasiparticle trap assisted-Electrothermal feedback-Transition edge (QET) Sensors. [ABSTRACT FROM PUBLISHER]