本研究，主要探討以自組裝單分子薄膜改質有機薄膜電晶體元件中不同的表面區域對於元件電性的影響。使用電晶體的結構為頂部閘極與底部接觸結構(Top-gate, Bottom contact)，其中ITO源極( Source )、汲極( Drain )與通道(Channel)上，皆以混合自組裝單分子薄膜調控表面特性。選擇兩種不同對位官能基之苯甲酸( Benzoic acid )作為混合自組裝單分子之材料，透過不同官能基之偶極矩改變ITO電極。於結果中發現，成長混合不同尾端官能基之苯甲酸溶液，修飾ITO電極，可將功函數調控至接近P型半導體的最高佔據分子軌道（HOMO），此方法可以使電晶體達到比較高的遷移率。此外，使用矽烷(Silane)的自組裝單分子薄膜，可同時修飾ITO電極與通道玻璃區域，探討通道上有無SAMs對於元件效能之影響，實驗結果發現通道改質對於元件效能影響較為顯著。

In this study, we utilized mixed self-assembled monolayers to modify the different regions of the device substrate and discuss the impact of these modifications on the electric characteristic of the organic thin-film transistors(OTFTs). A top-gate, bottom-contact device was used with the ITO source-drain electrodes and the channel region modified with mixed SAM. We show that passivating a mixed SAM which consists of two kinds of benzoic acid which contains different dipole moment constituent over ITO electrodes surface for changing the dipole moment and work function on ITO electrodes by a different functional group of SAMs. We found that when the work function of ITO electrodes is tuned to be close to the highest occupied molecular orbital (HOMO) level of p-type semiconductor by the mixed BA-SAMs method, a higher mobility than that on unmodified ITO electrodes can be reached. On the other hand, when mixed silane SAMs having the same function groups as the benzoic acid SAMs was used to modify the ITO electrodes and channel at the same time, the SAMs on the channel area has more impact on the electric property than the SAM on the electrode in a transistor.

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