Nanostructured Thin Sn-O-Te Films as Humidity and Ethanol Sensors.

Thermal co-deposition of Sn and TeO2 in vacuum is used for preparing thin Sn-O-Te films, build-up of an oxide matrix and a finely dispersed phase of Te, Sn and/or SnTe. The method allows further doping with desired elements both in the microcrystallites and at their interfaces with the aim to obtain films with improved gas sensing properties. The as-deposited films are amorphous and show very good characteristics as humidity sensors, operating at room temperature. Upon thermal treatment the structure and composition change and depending on the doping elements and the working temperature the observed nanocrystalline films show sensitivity to some reduction gases (ethanol, etc.). No cross-sensitivity of the crystalline films to water vapor is observed. [ABSTRACT FROM AUTHOR]