【作者】 杨梅；

【导师】 唐祯安；

【作者基本信息】 大连理工大学 ， 测试计量技术及仪器， 2005， 硕士

【摘要】 本论文课题属于气体传感器应用领域,课题源于国家863项目“环境检测微系统”,本课题是与中国电子科技集团第49研究所共同合作完成的。 本文阐述了两种SnO₂气体传感器的制备过程,即厚膜旁热式和新型Al₂O₃基底的微结构阵列式气体传感器,同时对CO气体以及干扰气体进行了测试和分析。 目前已有的集成式CO气体传感器多半是采用半导体工艺制造的多晶硅电阻做加热器,实践中发现多晶硅长期工作在260℃-350℃下,性能不稳定,无法满足长期使用的要求,因此本文对采用低温度系数的NiCr合金材料以及Au两种材料制作加热器进行了研究,并利用微机械加工技术研制出一种集成化阵列式气体传感器来实现双气体同时测试,并且采用不同幅度、宽度和频率的脉冲序列对传感器实现合理的温度调制,具有低功耗、高灵敏度、多功能、高性能、防振动、耐腐蚀等优点。这种特殊的悬桥式陶瓷基无内引线封装结构己申报了国家发明专利。 本文继承了传统SnO₂敏感材料的性能优点,并在进一步提高选择性方面做了新的尝试。在材料制备中,首先通过化学均匀沉淀法制备所需要的敏感材料SnO₂粉末,然后采用不同的重金属或氧化物做添加剂分别制备成了五种不同掺杂的气敏材料,并采用旁热式结构对其气敏性能进行了测试评估。结果表明,这些SnO₂气体传感器具有足够的灵敏度、响应速度和较低的制造成本。在此基础上,本文通过对这些气敏元件对CO及几种干扰气体的测试分析,筛选出了灵敏度、稳定性以及响应时间等性能均较好的掺杂敏感材料。 在新型传感器研制方面,将本文所研制的敏感材料与Al₂O₃基板相结合,对这种可采用微机械加工技术（加工基板）和常规微电子技术（加工电路加热器等）相结合的新型气体传感器进行了从设计到研制样品的全过程研究,初步制造出了A1₂O₃基片上的微结构阵列式气体传感器。指出了这种传感器研制中的难点和关键技术,为今后深入开展这种新型气体传感器的研究打下了基础。更多还原

【Abstract】 The project of this thesis involves gas sensor and its applications, which is from S863 program. All research of this thesis was cooperatively carrying out with the 49th Institute of China Electronic group Co.This thesis describes fabrication processes of two kinds of SnO2 gas sensors. They are deep-film side heating gas sensor and microstructure gas sensor array based on micromachined Al2O3 substrate plate. Sensitivity of the sensors to CO and some other disturbing gases is also experimentally and theoretical analyzed in this thesis.In general, integrated gas sensors utilize poly silicon as microheater. It is practically found that poly silicon heater is in general not stable after it operates at temperature of 260℃-350℃ for a long time. Therefore, NiCr alloy of low temperature coefficient and Au were experimentally investigated for a new heater. Then an integrated array was fabricated with combining the heater and micromachined Al2O3 substrate, by which test two sorts of gases can be detected simultaneously. A series of pulse with different amplitude and width were used to modulating the operation temperature of the sensors. The results showed that the sensors have advantages of low power consumption, higher sensitivity, multiple functions, and better shock resistance. This kind of special structure has reported the national invention patent.This thesis makes new attempt to further enhance the selective of SnO2 gas sensors by s inheriting the traditional merit of SnO2 sensitive material. In material preparation, SnO2 powder was firstly deposited by chemistry method, then some different heavy metals or oxide compound were used as additives to prepare five kinds of gas sensing materials. These sensing materials were evaluated by side heating structure. The result indicated that these SnO2 gas sensors have better enough sensitivity and speed of response, and low production cost. The optimum sensing material then was chosen by checking all the materials’ response to CO and some interference gases.In new sensor development aspect, this thesis combines prepared SnO2 sensitive material with a new sort of Al2O3 substrate that can be processed with micromachining. The whole fabrication process of the new type gas sensor joint of micromachining for substrate and routine process of microelectronic for electrodes was studied and a batch of preliminary samples sensor array was manufactured successfully.更多还原