Nanosized sensing films of titanium - tungsten oxides achieved by r.f. reactive sputtering

摘要

Nanosized thin film of Titanium and Tungsten mixed oxides were prepared by r.f. reactive sputtering assisted by annealing in dry air. Both micro-structural and electrical investigations on film characteristics were aimed at increasing the sensing performance of the layers. Differently from previously-investigated Ti: WO_3 layers prepared in a similar way, an high Ti content in the sputtering target results in a nanosized layer of TiO-WO_3 mixed oxides. The sensing properties of these novel film were tested to NO_2 and CO. The enhanced sensitivity and selectivity to NO_2 wit respect to the Ti: WO_3 films envisage employment of the layers as chemical sensors.