P1K-6 Synthesis and Characterization of Nanostructured Titania Film for SAW Oxygen Sensor

Both theoretical and experimental studies for a gas surface acoustic wave (SAW) sensor have shown that the sensing layer conductivity of semiconductor materials will change when it is exposed to special gases. The change in SAW velocity corresponds to the change in sheet conductivity. In order to improve the sensitivity of the sensing film, in this research, a nanostructured TiO₂ thin film was prepared using the self-assembled monolayer and sol-gel techniques. The TiO₂ thin film was used as sensing layer and was coated on the surface of SAW resonators (261MHz) for the purpose of oxygen sensing. The results of SAXRD, TEM and FE-SEM about TiO₂ film indicated that the film exhibited higher ordered mesostructure after calcinations at 400degC. The sensor was used to test oxygen concentration from 100 ppm to 10000 ppm (200degC), and the results showed that the nanosized TiO₂ thin film leaded to the improvement of the sensor performance