PECVD法制备的SnO_x气敏膜的色变机理

The Mechanism of Color Change of the SnO_x Gas sensing Film Prepared by PECVD Method

采用ＰＥＣＶＤ法制备了非晶掺Ｓｎ有机膜，经过退火处理得到ＳｎＯｘ气敏膜，考察了退火过程和气敏响应过程的阻温特性和颜色变化的关系，研究了表面掺Ａｇ对ＳｎＯｘ元件电阻、气敏性能以及颜色的影响，发现测量时膜表观色泽发生显著变化，并且颜色变化的深度与灵敏度大小相一致，颜色变化的快慢与响应时间的长短相一致，据此可望开发出色变气敏传感器。

Amorphors ultrafine tin contaning organic thin films were prepared by PECVD method. After being annealed, the film turned into ultrafine SnO x thin film which possesed gas sensitivity. In the present work, the resistance temperature properties and the color changes of the film during the annealing process and the gas sensing process were investigated. And the effects of doping silver in the film on gas sensitivity, resistance temperature properties and color changes were also investigated. By doping Ag, the color of the film changed obviously in face of reductive gases. It was found that the higher the sensitivity was, the more noticeably the color changed, and the higher the temperature was, the faster the color changed. Based on these facts, this film could be developed into color change gas sensors.