INTERFACIAL ISSUES IN THE DESIGN AND MAKING OF SOLID-STATE CHEMICAL SENSORS

The durability of a device is determined by the stability of its inter faces. The aim of this paper is to compare and to discuss problems con nected with interphase stability, as they reflect on chemical-sensor d esign and operation. Case studies will be considered, concerning issue s such as the degradation of the interface between the electrolyte and the auxiliary layer and interface-related degradation in semiconducto r sensors. In the former the active mechanism of response degradation is the formation of an interface at the electrolyte-auxiliary layer in terface, while in the latter the slow migration of defects throughout the grain dominates. All discussion will be carried out with reference to the relationship between preparation procedures and device structu re and chemistry.