Sandwich structure of Pd doped nanostructure TiO₂ film as O ₂ sensor

In this paper, we investigated the sensing properties of sandwich structure of TiO₂/Pd/TiO₂ thin films at various operating temperatures and oxygen partial pressures. The nanostructure TiO₂ thin films were prepared by the sol-gel method. Various thickness of Pd buried layer was deposited by magnetron sputtering of a pure Pd target. The films were characterized using X-ray diffraction analysis and SEM. It was found that TiO₂/Pd/TiO₂ thin films have the p-type behavior while the pure TiO₂ thin film is n-type semiconductor materials. We found that the structure of TiO₂/Pd/TiO₂ thin films with 10 s sputtering Pd layer has a better stability at 240 °C.