采用扩散和阶跃模型分析微型气敏元件时间特性  

Using Diffusion Reaction and Step Response Models to Analyze Characterstic Time of Micro Gas Sensor

作　　者：邢建平[1] 曾繁太[1] 李娟[1] 赵林[1] 石晓辉[1] 

机构地区：[1]山东大学信息科学与工程学院,济南250100

出　　处：《传感技术学报》2005年第2期318-320,324,共4页Chinese Journal of Sensors and Actuators

基　　金：山东省电子发展专项基金项目资助(2003118JNZX)

摘　　要：利用粉末反溅方法研制了酒敏灵敏度>20的性能良好的Si基SnO2/CeO2旁热式气敏元件,给出了重要参数之一的传感特征响应和恢复时间的实验结果,典型的稳态特征响应时间值在2.5s以上,恢复时间在7s以上;提出使用扩散反应模型对特征时间的物理意义及过程分析,在给定的边界条件下进行了解释;同时,建立了一种简单系统阶跃响应数学模型,并结合Matlab软件进行特征响应和恢复时间曲线处理的数学方法;最后,设计了有源串联相位超前微分网络以降低优化特征时间、提高元件响应速度。仿真和结果表明,特征时间显著减小,可提前约40%。We adopted anti-powder sputtering method to develop SnO_2/CeO_2 thin film gas sensor on substrate Si . The sensor has good performance of alcohol sensitivity more than 20. The gas sensor has side-heater. Experiment results show two important parameters, the curves of characteristic sensing response time and recovery time change. The typical characteristic response time of stable state is over 2.5 seconds. We make use of diffusion-reaction model to explain and analyze the physical meaning and process of characteristic response time under the given boundary condition. A mathematic model of step response of easy systems and a method combining with Matlab to deal with characteristic response time curve were proposed. An active series differential network of phase-lead was designed to reduce optimal characteristic response time of the gas sensor. The emulation and experiment results indicate that characteristic response time reduced around 40%.

关 键 词：薄膜材料 气敏元件 特征时间 

分 类 号：TN305.94[电子电信—物理电子学]