整合液相沈積二氧化錫薄膜與微機電結構之氣體感測器的設計、實現與量測

Abstract

本論文以微機電技術製造硫化氫氣體感測器，並利用液相沈積法成功的將二氧化錫薄膜沈積至微加熱平台上，使其具有微小化、低消耗功率、高靈敏度與可批次量產等優點。運用微機電製程技術製作懸橋式的微加熱平台結構，可以使得氣體感測器能在低電源供應下，迅速地達到最佳的工作溫度。在室溫環境下，微加熱平台的熱響應時間常數比未懸浮結構大約小於50倍以上。本研究設計蛇形與環形兩種微加熱器結構，以探討不同傳熱方式對感測薄膜特性的影響。有別於一般常見的薄膜沈積方式與機制，液相沈積法無需操作在真空環境下，且僅需使用簡單的設備便可沈積出高靈敏度的感測薄膜。本論文中對於微加熱平台結構與薄膜特性方面，分別進行熱響應與氣體響應特性量測，並探討其量測結果。

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.