Novel Printed Carbon Nanotubes Based Resistive Humidity Sensors

A resistive flexible humidity sensor based on carbon nanotubes (CNT) was designed and fabricated. Screen and gravure printing processes were used for the fabrication of the humidity sensor containing interdigitated electrodes (IDE), a sensing layer and a meandering conductive heater. The capability of the printed sensor was investigated by subjecting it to relative humidity (RH) ranging from 30% to 60%. This response demonstrated an overall resistance change of
_~
29% when the sensor was subjected to 60% RH, when compared to 30% RH. A maximum hysteresis of
_~
5.8%, at 40% RH, was calculated for the resistive response of the sensor. The fabrication method and sensor response are analysed and presented in this paper.