本論文主要為有機薄膜電晶體中導入一高分子材料LPEI，探討其對雙極性電晶體的影響與應用方面之研究。藉由電性分析了解元件的載子傳輸變化，表面能、極化電場圖與導納分析界面的特性，由拉曼、原子力顯微鏡與X光繞射儀分析Pentacene的結構。最後發現LPEI可以有效降低Pentacene元件的N型操作電壓。
電特性分析，導入LPEI後，元件的載子遷移率皆下降，但是LPEI在PMMA與Pentacene間可以有效降低N型臨界電壓。極化電場與導納分析，LPEI可以降低Pentacene元件的缺陷態密度與減少載子鬆弛時間，不過因為PMMA與LPEI偶極相消，導致額外電場的消失，所以有LPEI的Pentacene元件其電特性皆下降。表面能分析，LPEI表面的極性項高，所以不利於Pentacene成長。拉曼光譜分析，LPEI上的Pentacene，其264 cm-1的半高寬變窄，所以電子傳輸較PMMA上的Pentacene佳。原子力顯微鏡與X光繞射分析，因為PMMA玻璃轉換溫度接近380 K，導致PMMA在380 K時分子會大規模的震動。使PMMA上的Pentacene在380 K其結晶變差，而LPEI上的Pentacene在380 K不僅結晶變差，其結晶均勻性也變差。
光感測器分析，PMMA上旋塗LPEI可以提高Pentacene元件光響應能力。光記憶體分析，PMMA上旋塗LPEI對532 nm雷射光有記憶效應。溫度感測器分析，PMMA上旋塗LPEI可以藉由載子遷移率的增加感測環境溫度，但是降溫後元件會衰退。

This thesis investigated the effect of gate dielectric buffer layers on the electrical characteristics of ambipolar organic field-effect transistors (OFETs) and their applications. The pentacene-based ambipolar OFETs with a linear polyethylenimine (LPEI) buffer layer on a polymethylmethacrylate (PMMA)/silicon dioxide main gate dielectric was examined. With the LPEI layer, the n-channel characteristics of the ambipolar OFETs were improved and the threshold voltage was reduced. The pentacene/LPEI interface had relatively low interfacial trap density and shorter mean interface trap time constant than the pentacene/PMMA interface. Therefore, the potential and general usage of the LPEI buffer layer for pentacene-based ambipolar OFETs can be expected to be used in electronics.

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