CuO-doped SnO2 thin films as hydrogen sulfide gas sensor

CuO-loaded SnO2 element was earlier identified as a highly sensitive and selective H2S gas sensor. A number of techniques have been used by different authors for preparing thick and thin films of SnO2 doped with CuO, which among various metal oxides has outstanding promoter action for the sensitive detection of H2S by SnO2. Here we report the growth and characterization of CuO-doped SnO2 thin films by a thermal evaporation technique. These thin films show an extremely high sensitivity of similar to10(6) to few parts per million levels of H2S gas in air. The gas sensor is characterized at four operating temperatures and its long-term stability in response to H2S gas is tested over a period of 3 years. (C) 2003 American Institute of Physics.