隨著電晶體元件的日漸發展，除卻傳統金屬氧化物與高分子介電層，更多其他類型的優異介電層材料的開發亦十分重要，為此一具特殊凝膠態的固態電解質材料被開發作為電晶體之介電層，固態電解質介電層製作的元件電容值遠高於傳統氧化物介電層，可使電晶體元件在低電壓操作即可輸出高電流，於開發高效能電晶體元件勢必有極大的應用潛力，本研究將以離子液體與高分子材料製作擁有機械性質的固態電解質介電層，並應用於不同高分子主動層系統的電晶體元件中，研究分析固態電解質於高分子材料系統中的電特性以及與高分子主動層間的交互作用機制。
本研究以高分子Poly(vinylidene fluoride)(PVDF)作為載體，於其中添加離子液體1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][TFSI])製作固態電解質介電層PVDF-[EMIM][TFSI]，首先以半導體分析儀量測PVDF-[EMIM][FTSI]的Metal/Insulator/Metal (MIM)電容值，其電容值隨施加偏壓的變化方向趨勢與鐵電材料電容曲線相似，而拉曼光譜及X-ray diffractometer (XRD)分析結果亦顯示PVDF-[EMIM][TFSI]薄膜摻入離子液體後，會促進PVDF形成鐵電β相，降低非鐵電α相的形成，而使其MIM電容值的量測結果與鐵電材料相近。接下來將PVDF-[EMIM][TFSI]薄膜貼附於不同結晶品質之高分子半導體薄膜上作為固態電解質電晶體上閘極修飾層，並製作有機電晶體元件。
藉由將Poly(3-hexylthiophene-2,5-diyl)(P3HT)及Poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene](PBTTT)以不同溶劑成長薄膜而得出多種結晶品質的高分子主動層，由電特性量測結果發現，不同結晶度之半導體層薄膜對固態電解質電晶體電特性影響甚大，若貼附具有鐵電相之PVDF-[EMIM][TFSI]做為上閘極修飾層，較高結晶品質的半導體薄膜作為主動層的電晶體具有較良好電性，尤其以氯仿做為溶劑之PBTTT薄膜固態電解質電晶體具有最佳的電特性。
最後，研究不同閘極材料對PBTTT有機固態電解質電晶體電特性的影響，分別使用銅膠帶與導電高分子poly(2,3-dihydrothieno-1,4-dioxin) (PEDOT) 為閘極材料，當使用銅膠帶為閘極時，元件會呈常開的非理想狀態，然而，使用PEDOT為閘極時，元件可表現出較佳的電特性。閘極電極材料會使得元件電性極為不同，歸因於過大的閘極電壓會使得半導體層PBTTT之結構產生變化，導致以銅膠帶做為閘極之元件會發生元件常開的狀態，最後成功利用具有較佳電性之PEDOT做為閘極電極之固態電解質電晶體模擬出低電壓操作人類神經突觸行為。

This study investigated the influence of polymeric semiconductor and gate electrode materials on the electrical characteristics of solid electrolyte-gated organic thin-film transistors (SEGTs). Two kinds of polymeric semiconductors, namely, poly(3-hexylthiophene-2,5-diyl) (P3HT) and poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene] (PBTTT) were prepared by solution process using organic solvents with different boiling points and used as an active layer with various morphologies. Poly(vinylidene fluoride) (PVDF)/ionic liquid (ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [EMIM][TFSI]) solid-gel electrolyte films were prepared to serve as the top gate dielectric. Electrical characteristics of the as-prepared SEGTs with different gate electrodes such as copper (Cu) and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) ] were also compared. The microstructural and dielectric properties of PVDF/[EMIM][TSFI] films were investigated using X-ray diffraction, Raman spectroscopy, and impedance spectroscopy techniques. Results showed that PVDF in the gel electrolyte films tended to form ferroelectric crystalline phases and thus exhibited excellent ferroelectric dielectric properties. The enhanced electrical characteristic of SEGTs were obtained when using high-crystalline quality polymeric active layers, especially for PBTTT. The electrical properties of the Cu gate electrode were specifically compared with those of the PEDOT:PSS gate electrode for PBTTT-based SEGTs. The devices with PEDOT:PSS as the gate electrode showed better characteristics. We then successfully used PBTTT-based SEGTs to simulate the electrical properties of low-power consumption nerve synapses in humans.

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