热处理温度对Pd掺杂SnO2薄膜的微结构和H2气敏特性的影响

he influence of annealing temperature on the microstructure and H2 sensing properties of Pd-doped SnO2 sputtered thin films were investigated. The as-deposited film was amorphous and would crystallize to tetragonal SnO2 structure when the annealing temperature was above 350 C. The films were composed of columnar grains. Both crystallite size and grain size increased with an increase in annealing temperature. H2 sensing measurements showed that gas sensors based on these films obtained the peak response to 1000 ppm H2 at an operating temperature of 100 C and showed a good reversibility. The Pd-doped SnO2 thin film annealed at 450 C showed the highest response to H2. The improved gas sensing properties were attributed to the porosity of columnar nanostructures and catalytic activities of Pd doping.