EFFECT OF ELECTRODE ALTERATIONS ON THE AC BEHAVIOR OF LI2O-ZNO HUMIDITY SENSORS

The dielectric behaviour of humidity sensors based on Li-doped ZnO has been investigated at frequencies from 1 Hz to 1 MHz, at room temperat ure. Sputtered gold electrodes and Teflon(R) film electrodes were used to obtain the dielectric response of the system electrodes/sensor to humidity changes. It is suggested that the main dielectric relaxation observed when Teflon electrodes are used corresponds to one of the thr ee different dielectric relaxations observed for the system with gold electrodes. Current theories are used to discuss the origin of the obs erved relaxations.