本研究中，以具有強拉電子基團-氟之F4-TCNQ放置在汲/源極與有機半導體層之間做為插入層；並使用高介電常數溶液式鋯鈦酸鋇材料應用在有機薄膜電晶體之絕緣層；成功製作出低閘極操作偏壓(<-5 V)，並由實驗中發現F4-TCNQ插入層的最佳化厚度為1 nm，有效達到提升載子移動率(從9 cm2V-1s-1增加至11.27 cm2V-1s-1)，並改善臨界電壓(從-1.5 V 至-1.05 V)，對於接觸阻抗也有明顯的改善(從44 kΩ降低至29.58 kΩ)，使有機薄膜電晶體即使操作在低電場下也能擁有較低接觸阻抗。並由原子力顯微鏡量測得知在插入1 nm F4-TCNQ有最佳的平坦度。隨著插入層的厚度增加，臨界電壓有往正電壓偏移的趨勢。因此，設計MIS結構進行C-V量測來觀察不同厚度的插入層對電容量測的影響，進而推算有機主動層的載子濃度變化，並探討載子濃度與臨界電壓之間的關係。本研究已經成功利用有機材料做為插入層，且有效提升有機薄膜電晶體元件特性，並探討載子濃度與臨界電壓之關係，對於有機電子的研究有所助益。

In this study, F4-TCNQ containing a strong electron-withdrawing group as an inserted layer between the drain/source electrode and organic semiconductor and a highly dielectric barium zirconate titanate solution as insulator were applied to organic thin-film transistors (OTFTs). OTFTs operating at a low gate voltage (< -5 V) were fabricated successfully. The optimum thickness of the inserted F4-TCNQ layer was 1 nm. The performance of OTFTs was improved: carrier mobility increased from 9.00 cm2V-1s-1 to 11.27 cm2V-1s-1, threshold voltage shifted from -1.50 V to -1.05 V, and contact resistance decreased from 44.00 kΩ to 29.58 kΩ. The OTFTs exhibited low contact resistance even when operating at a low electric field. Meanwhile, atomic force microscopy revealed that a thickness of 1 nm was the optimum flatness for F4-TCNQ. However, the shift in threshold voltage depended on the increasing thickness of F4-TCNQ. To explain this phenomenon, an MIS structure was used for measuring the capacitance of the inserted F4-TCNQ layers of different thicknesses. In the C-V measurement, carrier concentration in the organic semiconductor layer with different thicknesses of inserted F4-TCNQ layers was calculated. The relationship between carrier concentration and threshold voltage was also examined.
In sum, this study used an organic material as an inserted layer to further enhance OTFT performance. The study also explored the relationship between carrier concentration and threshold voltage to advance organic electronics.

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