Highly integrated surface potential sensors

For chemical imaging, surface potential sensors with multiple active sites are desirable. In the first part of this study, it will be described how simply by changing the geometry of established surface potential sensors, like (i) microelectrode arrays, (ii) electrolyte insulator-semiconductor (EIS) diode arrays and (iii) field-effect transistor (FET) arrays, devices with an enhanced integration density of active sites, called (i) light-addressable microelectrode arrays, (ii) the light-addressable potentiometric sensor (LAPS) and (iii) the field-effect-addressable potentiometric sensor (FAPS), can be designed. In the second part of this study, it will be discussed, especially in the case of the LAPS, whether this gain in integration density of active sites has to be paid with a loss in potential sensitivity. (C) 2000 Elsevier Science S.A. All rights reserved.