Dilute hydrogen sulfide sensing properties of copper oxide-tin oxide thin film prepared by low-pressure evaporation

摘要

Thin films of SnO/sub 2/ and CuO-SnO/sub 2/ were prepared by evaporation from tin and copper metals under a low pressure (1 torr) of air atmosphere. As observed with AFM, these evaporated films had unique microstructure in which discrete clusters of SnO/sub 2/ grains contacted to each other three-dimensionally with large mesopores penetrating between. The film added with a small amount of CuO was very sensitive to H/sub 2/S in air, being able to detect dilute H/sub 2/S close to 0.02 ppm at 300/spl deg/C. The high sensitivity seems to result from the unique promoting effect of CuO coupled with the unique microstructure of the film.