【作者】 余华梁；

【导师】 黄世震；

【作者基本信息】 福州大学 ， 微电子学与固体电子学， 2005， 硕士

【摘要】 材料的制备和元件的结构设计是研制半导体气敏传感器的关键环节。我们创新性地设计了一套实验装置,采用气相反应法,以纯钨丝为原料, 制备WO₃ 纳米气敏材料。采用XRD, SEM, TEM对材料进行结构分析和形貌观察, 发现WO₃ 材料的微观结构与气敏性能紧密相关, 材料的颗粒尺寸小, 表面粗糙不平, 有利于气体的吸附, 从而对气体更敏感。根据塞贝克效应的原理, 我们提出气敏传感器的一种新结构, 又以上述方法制得的WO₃ 纳米粉末为基材制作成元件, 这种新型元件能够输出数十毫伏的直流电压, 这对于信号的放大与处理十分方便。在实验中对NO₂ 气体进行检测,结果表明,当NO₂ 浓度为20×10^-6 加热功率8.5W 时,传感器的灵敏度可达13, 响应时间为5s, 恢复时间为16s, 并且灵敏度随NO₂ 浓度而变化。因此, 利用塞贝克效应来探测气体是一条可行的新思路。更多还原

【Abstract】 The preparation of material is critical to fabrication of gas sensor made from semiconductor. Nanometer WO₃ was synthesized in a new designed instrument by gas-state reaction with tungsten filament.By XRD、SEM and TEM, we investigated the structure and surface morphologies and researcher on the relationship between structure and sensing properties of gas sensing materials. The conclusion is sensing properties of the component completely decided by its microstructure. The component made from smaller particles with rough surface is more sensitive them the one made from bigger particles with smooth surface. I believe that rough surface is more active than smooth surface when reacting to gas.Furthermore, we designed a new type gas sensor based on Sybac effect.Then we made nanometer WO₃ into these type gas sensors. Each of them can afford a direct voltage ranging from 0-100mV. The gas sensing measurement results revealed that these sensors have a certain response to NO₂ with good response characteristic. To 20×10^-6 NO₂,with good response time of 5s and recovering timeof 16s, the sensitivity is 13 and changes with the density of NO₂. So the conclusion is that this gas sensor based on Sybac effect is aprospective gas sensor of new type.更多还原