CHARACTERIZATION OF A NANOSIZED TIO2 GAS SENSOR

Thin films were obtained by r.f. reactive sputtering from a Ti.1W.9 ta rget onto a Si substrate followed by annealing in air at 800 degrees C . The thermal treatment results in a nanosized TiO2 thin film with hig h surface-to-volume ratio. The nanosized structure, its stability , to gether with the ease of preparation, make this material suitable as a gas sensor. The sensing layer proved capable to detect 20 ppm of NO2 a t a temperature suitable for monitoring of exhaust gases of engines. I ts high sensitivity suggests use of this sensor for environmental purp oses.