Chemical micro-sensors have the potential of a wide range ofapplications that include odor sensing in food industry, environmentalmonitoring, improvedprocess control, detection of hazardous chemicals, medicaldiagnosis, and control of automobile emissions.

In this thesis,a model is developed describing the electrical response of a thin-film, conducting polymer sensor to an air mixture containing different target gas species. Numerical methods for discretizing the initial-boundary value problem defining the film conductance model are presented. Nonlinear parameter identification methods are used to identify a subset of the model parameters.

Two models of sensor operation are studied. In the first case, the isothermal response of the sensor to time varying gas phase concentration is considered. The effectiveness of sensor cleaning is studied in the second case in which the sensor substrate temperature is periodically increased to drive out adsorbed gas species. Good agreement is found when model predictions are compared with published experimental results.