SO2薄膜气敏传感器光学特性的分析

采用光度法以及椭圆偏振法测量技术对掺有贵金属或过渡金属元素的SnO2薄膜以及在不同Po2/PAr比条件下制备的VOx系列的薄膜进行了系统的光学气敏特性测试。比较了各种薄膜对SO2气体的光学气敏特性，发现在一定条件下制备的SnO2/Pd、VOx薄膜对SO2气体在可见光区有很好的灵敏性，SnO2/Zr薄膜对SO2气体在近红外区有很好的的灵敏性。定性地用光学能隙的变化和自由载流子浓度的变化说明了薄膜在吸附气体后的光学性质的变化。

Optical Characteristics Analyses of Thin Film SO2 Gas Sensor

The optical sensitive characteristic of SnO 2 and VO x thin films to the gas SO 2 is investigated with photometric and ellipsometric methods. It is found that thin films of the Pd doped SnO 2 and no dopant VO x have good optical sensitive characteristics to the gas SO 2 in the visible range, and the Zr doped SnO 2 film in the near infrared area. The results show that the change of the optical characteristic is directly related to the variation of optical gap and the concentration of free carrier in the thin films.