本研究利用加入CuPc緩衝感測層於有機薄膜電晶體元件，藉此提高元件對酒精氣體的響應度及穩定性。由於感測層的特性對氣體感測器而言，為最重要的影響因素，因此本研究藉由改變不同通道層鍍率和加入不同厚度的CuPc緩衝層於感測器中，一方面提升元件特性；另一方面藉由CuPc本身亦對酒精氣體具良好的反應能力來當作雙感測層的應用，藉此提高元件對酒精氣體之響應度。由實驗結果可知，在通道層Pentacene厚度50 nm且鍍率為1.5 Å/s和緩衝層CuPc厚度為5 nm時，其場效載子移動率可到達為2.283×10-1 cm2/Vs，同時在100 ppm的酒精氣體濃度下，其響應度能達到70%。此結果相較於未加入緩衝層CuPc時，其場效載子移動率為6.74×10-2 cm2/Vs，在100 ppm酒精濃度下其響應度35%等結果有明顯提升，元件對酒精氣體響應度和特性表現更佳。

The goal of this research is to enhance the sensitivity and stability of the OTFT ethanol gas sensor by adding a CuPc buffer-sensing layer. Because the sensing layer is the most important part of the gas sensor, this research modulated the thickness of CuPc layer and changed different evaporation rate of the Pantacene active layer of the ethanol gas sensor device to improve the performance. Moreover, the CuPc buffer layer, which possessed well sensitivity for ethanol, can effectively enhance the sensing response of the gas sensor. According to the experimental results, when the thickness of pentacene active layer was 50 nm with evaporation rate of 1.5 Å/s and CuPc buffer layer was 5 nm, the optimized characteristic can be obtained. The mobility and gas response of the OTFT gas sensor with 5-nm-thick CuPc buffer layer its mobility achieved 2.283×10-1 cm2/Vs and 70% under 100 ppm ethanol. The results were much better than the one without CuPc buffer layer which possessed the mobility and gas response of 6.74×10-2 cm2/Vs and 35% under 100 ppm ethanol, respectively.

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