Micromachined sensors based on ZnO structures and their thermo- and photo-activated response to reducing gases

ZnO rods were grown via aerosol-assisted chemical vapor deposition on Si-based micromachined platforms. The photo- and thermo-activated sensor characteristics were evaluated towards carbon monoxide, ethanol and toluene. Results proved photo-activated response at room temperature with improved response and selectivity compared to the thermo-activated response at 250 °C. This property becomes significantly advantageous as it allows for the sensor to operate without heating.