基于γ-Al_2O_3膜微加工煤油传感器研究

Study on micromachining kerosene sensor based on γ-Al_2O_3 membrane

基于半导体式气体传感原理,提出了利用MEMS技术将电化学生长的Al2O3膜加工成微热板结构载体,采用平面薄膜工艺制做Pt薄膜加热电阻和信号电极。在微热板的2个电极上,涂敷γ-Fe2O3-SnO2-Pt-Pd形成煤油蒸气敏感单元,实现在微结构体上气体检测的二单元集成。传感器采用脉冲工作方式,工作周期为30 s,在加热峰值形成高温400℃的煤油检测条件。测试结果表明:煤油(标志物:癸烷)检测可实现体积分数(0～7000)×10-6范围,90%的吸附响应时间小于8s,脱附响应时间小于12s,传感器信号输出与煤油体积分数有对应的全对数线性关系。

Based on the theory of semiconductor gas sensor, a micro thermal plate structural carrier, which is processed utilizing MEMS technology by electrochemical grown A12 03 membrane is presented, planar thin film process is used to manufacture Pt thin film heating resistor and signal electrode. On the two electrodes of micro thermal plate, painting ＂y-Fe2 03 -SnO2-Pt-Pd to form kerosene streaming sensing unit, to realize the integration of two units for gas test on the micro structure. The sensor works on pulse mode,working period is 30s, when heated, the temperature can achieve 400 °C, and it forms the test condition of kerosene. The test result shows that kerosene （marker objeet-quinane）test can realize volume fraction from 0 to 7000 x 10-6,90 % absorbing response time is shorter than 8s,separating response time is shorted than 12s, the relation of the signal output of sensor and the volume fraction of kerosene is complete logarithmic linear.