Gas dependent response in temperature transient of SnO/sub 2/ gas sensor

The authors describe the gas dependent response observed in transient conductance patterns of a SnO/sub 2/ gas sensor caused by surface temperature changes, and its relationships to sensor variations. SnO/sub 2/ gas sensors were investigated for gas identification. The underlying objective was to determine how to extract the gas-specific information to the fullest extent from a single gas sensor. A temperature transient method was used. A stepwise change in heater voltage for the sensor caused a conductance change of the sensor, which showed a gas dependent transient response. The transient responses were examined after dividing them by the conductance response measured in clean air, and distinctive peaks of the response were observed. The peak times depend on each particular gas species. Therefore this method is useful for identifying gas species. The characteristics of several types of gas sensors were also studied. >