本篇論文利用Poly(3-octylthiophene-2,5-diyl)並搭配刮刀塗佈聚苯乙烯奈米球(Nano-sized polystyrene sphere)技術製作高孔洞密度垂直式二極體元件，藉由偵測通過氨氣氣體造成的電流變化得知氨氣的濃度，並且擁有製程成本低廉、即時偵測、高靈敏度、非侵入式等優勢。並且著手將整體感測系統微小化，通過各種實驗測試排除人體呼氣水氣，找出合適的氣體採集方式提供呼氣感測另外該方法必須能穩定度的量測，並且系統能夠偵測到100 ppb氨氣濃度，而在本篇論文中也提到利用許多不同量測方法來簡化量測系統減少系統成本，另外可搭配微處理器模組來運算感測元件電壓降變化，取代量測機組使感測系統成為可攜式即時量測設備。

We use Poly (3-octylthiophene-2,5-diyl) to serve as sensing material and producing a high porous density vertical diode by blade coating process to detect ammonia. The ammonia gas sensor in air background sensing system can detect the ammonia concentration from 100 part per billion (ppb) to 1 part per million (ppm) with good resolution. Besides, we try many ways to enhance the sensing system’s reliability. For example, utilizing the gastight syringe to avoid the electric signal noise during gas injection. And we also investigate how to collect human breath properly, thus sensing system can detect breath-ammonia without disturbing by the high humidity in breath or the variation of background flow. In addition, high-end measurement instrument is replaced by a microprocessor, which computes ammonia sensor’s voltage signal to identify the ammonia concentration to miniaturize sensing system. The miniaturized portable ammonia sensing system has many advantages such as non-invasive sensing, real-time sensing, low-cost and room temperature operation.

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