本研究使用[Poly(3-hexylthiophene-2,5-diyl)(P3HT)]高分子作為電晶體之主動層，並於通道上貼附離子凝膠作為介電層，可使原本操作於大電壓的電晶體能轉變成低電壓操作。
首先使用柱狀、孔洞及不同結晶品質之P3HT薄膜結構作為電晶體之主動層，並利用不同金屬材料作為電晶體的源極與汲極，探討將離子凝膠貼附於不同主動層結構之通道上時，元件電特性上的差異，並透過拉曼光譜儀，分析元件經電化學摻雜後，電晶體主動層的微結構變化。
本研究利用離子凝膠所產生的大電容效應，成功的製作出能在低電壓下操作的電晶體，且經實驗中發現，當有較高結晶品質的P3HT之薄膜時，可減少離子摻雜入P3HT中，降低主動層微結構的破壞，而當主動層結構為柱狀與孔洞結構時，能利用PMMA擁有吸引離子的特性，可改變離子摻雜進入主動層的區域，展現出不同元件的電特性，增加元件可應用性。而發現當使用銀作為元件的源汲極時，會有較低的電流穩定度，主因推測銀容易與離子凝膠中的硫元素產生反應，因此當改用金作為元件電極時，能大幅改善元件穩定度。

In this study, poly(3-hexylthiophene) (P3HT) was used as an active layer of organic thin-film transistors (OTFTs). An ion-gel film, which acts as a dielectric layer, was pasted onto P3HT to fabricate low-voltage-driven OTFTs. P3HT active layers with different microstructures were prepared. Different metals were adopted as the source and drain electrodes of OTFTs. The electrochemical doping effect of the ion-gel dielectric layer on the microstructure of various P3HT thin films and the electrical characteristics of the corresponding devices were investigated. We observed that the high crystalline quality of P3HT thin films could reduce the doping of ions and their damage to the microstructures of P3HT active layers. The addition of poly(methyl methacrylate) (PMMA) into P3HT active layers could adsorb ions. Different structures of PMMA that formed in P3HT active layers resulted in different doping sites of ions, leading to the different electrical properties of OTFTs. The devices with silver electrodes had a lower stability of output current compared with those with gold electrodes during continuous operation, which may be due to the reaction between the silver and sulfur of the ion gel.

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