Design, Implementation and Measurement of a MEMS Type Gas Sensor with SnO2 Sensing Film Prepared by Liquid Phase Deposition Method

• Main Authors: Huang, Yen-Chi, 黃彥期
• Other Authors: Chiou, Jin-Chern
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/10803727673561292010

碩士 === 國立交通大學 === 電控工程研究所 === 99 === In this thesis, a micro H2S gas sensor with liquid phase deposition (LPD) based sensing film on the micro hotplate, was successfully implemented by utilizing MEMS fabrication technology. Versatile advantages including miniaturized structure, low-power consumption, high-sensitivity and high-yield production were achieved by the proposed method. Additionally, cantilever bridge structure design allows shorter heating time with low power supply to reach required working temperature. The thermal response time constant of proposed structures shows more than 50 times faster than the un-suspended structures under room temperature. Moreover, 2-types of heater designs, including serpentine and annular structures, were tested for heat conduction performance comparison. By applying the proposed LPD method, complex equipments with vacuum chamber were no longer needed for high-performance sensing film fabrication. Finally, related heat and gas response characterization for micro-heater and thin-film structure were measured and discussed, respectively.