CHEMICAL MICRO-SENSORS

Chemical industries, environment and many other applications require t o know the concentration or the presence of chemical species. Numerous phenomena can be used to convert a chemical presence into an electric al signal : fabrication costs are deciding for the choice. Recent deve lopments in the domain of silicon microfabrication techniques permit t o realise with collective fabrication chemical integrated, sensors. No wadays, two approaches are developed: CHEMFET type sensors, Electroche mical type sensors. The principal failure of these sensors is the lack of reliability. A possible improvement seems to be the use of multise nsors systems, associated with neural network pattern recognition.