【摘要】 用粉末溅射方法制备了体掺杂型SnO2 :Pt薄膜和表面层掺杂SnO2 /SnO2 :Pt双层膜 ,测量了薄膜在不同CO体积分数下的灵敏度和电导 .研究了两种薄膜对CO响应的次方因子 ,测定了工作温度和薄膜厚度对次方因子的影响 .实验结果表明 ,由室温至 2 0 0℃ ,这两种薄膜对CO气体都显示了较高的灵敏度和选择性 ,两种薄膜电导对CO的响应服从次方定律关系 ,薄膜工作温度及厚度对次方因子均有影响 ,次方因子在 0 .5～ 0 .8之间 ,次方因子在膜厚 60～ 70nm附近存在极大值 .对两种薄膜测量结果的比较说明 ,这两种薄膜的气敏响应主要发生在薄膜表面更多还原

【Abstract】 The two types of bulk doped thin films, the SnO 2:Pt film and the doubl e-layer SnO 2/SnO 2:Pt film, were prepared by powder sputtering. The sensitiv ity a nd the conductance of the films were measured under different CO volume fraction s. The power exponents for the two kinds of the films during CO sensing response were investigated. The influence of the working temperature and the film thickn ess on the power exponent was studied. The experimental results indicated that both the films exhibited high sensitivity to CO from room temperature to 200?℃. The con ductance of the two kinds of the films obeys the power law. The power exponent i s influenced by working temperature and the film thickness. It is in the range o f 0.45～0.80. There exists a maximum of the power exponent when the film thickne ss is 60～70?nm. It is found that gas sensing response for both the films takes p lace mainly on the surface of the films by comparing the gas sensing characteris tics of the two films.更多还原