Thick and thin film p-type conducting perovskite hydrocarbon sensors - a comparative study

Hydrocarbon sensitivity of a series of p-type conducting strontium titanate-ferrate, Sr(Ti/sub 1-x/Fe/sub x/)O/sub 3-/spl delta// conductometric sensors was investigated It was shown that in the temperature range between 350/spl deg/C and 450/spl deg/C, the resistance of thick film and thin film devices changes considerably in the presence of propane. The sensor response is rapid and reversible. However, cross interference experiments show a different behaviour of thick and thin film sensors when exposed to hydrogen. A model for this behaviour based on differential gas diffusion into the sensor material is proposed.