利用官能化之表面改質提升多晶矽奈米線對氨氣靈敏度

Abstract

本論文研究是以探討利用多晶矽奈米線場效電晶體作為即時的氨氣感測器。然而，多晶矽奈米線場效電晶體在低氨氣濃度時，其感測能力有限。為了解決此類議題，利用具有官能基的寡聚物在多晶矽奈米線場效電晶體的表面，進行的表面改質，使表面具有官能基分子，增加對氨氣的吸附，使多晶矽奈米線場效電晶體對氨氣的感測能力明顯改善，進而提升靈敏度，且在氨氣低濃度變化的感測上，具有良好的鑑別度。經過官能基的寡聚物的表面改質後， 元件的電流比值可達到26，與未改質前的互相比較，感測元件的靈敏度可以提升六倍之多，且在低氨濃度變化時，具有明顯的鑑別能力。

In this thesis,we use the poly-silicon nanowire field effect transistor (poly-Si NW FET) as ammonia gas sensor. However, the poly-silicon nanowire field effect transistor is limited at low NH3 concentration. In order to solve this issues, modifying the surface of poly-silicon nanowire field effect transistor by oligomer functionalized that can increase amount of ammonia adsorption. The poly-silicon nanowire field effect transistor was improved significantly for ammonia sensing and the sensitivity was enhanced. The poly-silicon nanowire field effect transistor also has good distinguishability at low NH3 concentration. After modifying the surface by oligomer functionalized, the NH3/N2 current ratio can reach 26. And the sensing device can enhance more than six times and it has obvious distinguishability at low variation NH3 concentration.