SnO2气敏元件烧结工艺与电性能关系的复阻抗分析

采用平面丝网印刷工艺制备ＳｎＯ２厚膜气敏试样，分别在不同烧结温度和保温时间下于空气中烧成，测量试样的灵敏度和稳定性，并通过复阻抗分析方法，研究了ＳｎＯ２气敏元件烧结工艺和电性能的关系，探讨烧结工艺对敏感材料微结构的影响，结果表明，适当调整结工艺参数可以使元件既有较高的气体灵敏度又有良好的长期稳定性，复阻抗分析表明，随保温时间延长，试样的电阻－电工线半圆弧的弥散角逐渐减小至零，说明适当延长保温时间使

Complex Impedance Analysis for the Relationship of Calcining Process and Sensing Properties of SnO2 Gas Sensors

The SnO2 thick film gas sensors were prepared by using a standard screen printing technology and calcined at different temperature and time. By measuring the sensitivity and long-term stability and using complex impedance analysis, the effects of calcining temperature and time on sensing properties and microstructure of the thick films were researched. Gas sensors with high sensitivity and long-term stability can be prepared by choicing suitable calcining process parameters. Complex impedance analysis indicates that the depressed angles of semicircular arc will reduce to zero with the extension of calcining time. The reducing of depressed angles means the distribution of relaxation time at the grain boundary becomes more uniform. This result shows that the distribution of defects and pores, and the grain connected shapes at the grain boundary tend to be more uniform and stable with the extension of calcining time.