Technical Paper
Development of Microfabricated Chemical Sensors Operated in the Differential Mode
1993-07-01
932204
Chemical and electrochemical sensors and sensor arrays can be produced using microfabrication and micromachining technologies. These technologies permit the formation of three-dimensional structures and also produce geometrically well-defined, highly reproducible sensor prototypes. Most present chemical and electrochemical sensors operate using a single device for absolute measurements. There are many circumstances in which interference by other species, the signal-to-noise ratio, and/or the selectivity and sensitivity are less than desirable when using a single sensor. It is feasible to employ a differential mode of sensor operation to overcome these weaknesses. In the differential mode of measurement, a pair of identical sensors is used, with one sensor as the active device, and the other serving as a reference. The active device may incorporate an electrocatalyst, while the reference sensor does not.