CO2 sensing by work function readout of ZnO based screen printed films

Work function readout of screenprinted polycrystalline ZnO-based layers is investigated for CO₂ detection. Numerous sensing materials have been developed and applied to the GasFET for several target gases like NH₃, NO₂, CO and humidity [1]. Special emphasis has been placed on the development on sensing layers for CO₂ detection [2], but the CO₂ sensitive materials identified so far have drawbacks regarding delicate manufacturing, long term stability or need for heated operation. ZnO-based materials may overcome these drawbacks, as the first results shown here will demonstrate.