本研究藉由印刷電極結合軟性基板的製程，成功開發低成本、低功耗的電阻式氣體感測器。在指叉電極上塗佈一層高分子與導電材(碳黑)複合薄膜，藉由量測其吸脫附氣體的電阻變化值，來得知其量測氣體的能力。透過七個感測器陣列，可在數個感測區塗佈不同的高分子，每種高分子會對氣體有不同的響應，分析其電阻變化值，即可達到辨識或分類氣體的目標。因應環境中對人體的有害的揮發性氣體及易燃性的爆炸性氣體，氣體感測器可即時監控並避免危害，因此其對於物聯網的整合或智慧穿戴式裝置的應用，乃不可或缺的一環。
感測器電極圖形共設計出八種不同線寬線距組合，並與工研院合作，將電極印刷在玻璃及軟性基板PET上，運用已開發的感測材料PNVP塗佈在試片上，進行對乙醇與甲烷的測試，找出反應及靈敏度最大的線寬/線距組合為20μm/20μm，其對乙醇感測極限約為40ppm，對甲烷的感測極限則為32ppm，且乙醇與甲烷的反應變化相反。此外也比較了PNVP、P4VP、PS等三種不同感測材料對乙醇及甲烷的反應大小，以及彎曲感測器對量測的影響，並做穩定性、重覆性、對濕度影響等感測器能力分析，達成建立穿戴式感測平台及其應用的目標。

　　In this research, we combine the printed electrodes and flexible substrate to develop a low-cost resistive gas sensor with low energy-consumption. After coating a thin layer of polymer and carbon black mixture, the ability of measuring gas can be derived by analyzing the resistance change due to the adsorption of the gas molecules by the polymer. The sensor array containing seven sensors can be coated with different polymer so that every polymer will response to gas differently. The goal of identifying or classifying gases can be reached by analyzing the resistance change.The integrated gas sensor not only can monitor those harmful volatile organic compounds and explosive gases real-time and also being part of the Internet of Things acting as the application of smart wearable devices.

Eight different combination of electrode’s width and gap are designed. ITRI helps to do the printing fabrication on the glass and PET substrates. One of the developed sensing materials PNVP is coated on the chips and tested by ethanol and methane. The most sensitive design of electrode’s width/gap is 20μm/20μm.The LOD towards ethanol is 40ppm and 32ppm for methane. The resistance change of the two gases is opposite. Besides PNVP, sensors coated with other polymers such as P4VP and PS are measure by different concentration of gases and derive the sensitivity of each. Since the substrate is flexible, bending influence to sensor is also considered.The stability test, reproducibility test are performed as well. Through these experiments, the gas sensor has great potential to achieve the purpose of establishing a wearable sensing platform.

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