微型热导检测器的结构设计研究

Design and research of micro thermal conductivity detector structure

基于MEMS技术设计了一种新型结构的微型热导检测器。选择了高电阻率、高温度系数的热敏元件,以四臂直通式作为结构模型,并对结构器件材料的热耗散性能进行仿真分析,采用热损耗最小的聚酰亚胺作为绝热层,以微加工工艺为基础完成了微型热导检测器的制作。实验结果表明,该新型热导检测器测量体积分数85%的标准气体时最大误差为0.068%,相比传统的热导检测器灵敏度提高约25%。

Based on MEMS technology, a novel structural micro thermal conductivity detector was designed. High resistivity, high temperature coefficient thermistors were chosen as elements, the four beam straight form was used as the structural model, the heat dissipation properties of the detector’s structural materials were simulated and analyzed, the micro thermal conductivity detector was fabricated using polyimide as the adiabatic player which had the minimum heat loss. The test results indicate that the max detection error of the volume fraction of 85% of standard gas is 0.068% by using this detector, whose sensitivity is about 25% higher than that of traditional thermal conductivity detector.