利用含氰類官能基修飾以提升多晶矽奈米線場效電晶體表面對氨氣感測之靈敏度

Abstract

本研究為探討多晶矽奈米線場效電晶體對低濃度氨氣之感測能力。因多晶矽奈米線場效電晶體欲進行低濃度之氨氣感測時，其感測能力有限，故為了提升其對低濃度氨氣之感測能力，本實驗將含有氰類官能基寡聚物的有機材料修飾於多晶矽奈米線表面上，以加強多晶矽奈米線表面對氨氣分子的吸附能力，進而提升多晶矽奈米線場效電晶體對低濃度氨氣的感測能力。另外，為了瞭解環境因素對低濃度氨氣下感測能力之影響，本實驗進一步將多晶矽奈米線場效電晶體分別置於不同相對濕度之下進行量測，確認氨氣分子與水分子之間的競爭關係。最後，其實驗結果亦證實表面經修飾含有特定官能基之多晶矽奈米線場效電晶體，較表面未修飾之元件，對低濃度氨氣的感測能力提昇120%，因此極適合利用於醫學中對於患有肝病患者的氨氣檢測。

In this thesis, the ammonia gas senser of poly-Si nanowires field effect transistors (poly-Si NW FETs) was discussed. The ammonia sensing ability of poly-Si NW FETs is limited at low-concentration. Therefore, the NW surface was further modified by cyanide group containing materials to enhance the low-concentration ammonia sensing ability. The cyanide-based compound has chemical adsorption which can help ammonia gas molecular to absorb on the NW surface and that can improve the low-concentration ammonia sensing ability. Besides, in order to understand the effect of environment factor, we also tested the sensing ability under different relative humidity. Finally, the experiment results showed that the 120% sensing property enhancement of modified poly-Si NW FETs are able to be applied for biomedical detection in the liver disease.