本論文研究以Regioregular Poly(3-hexythiophene) (高度立體規則度聚(3-己烷基噻吩)，簡稱RR-P3HT)為有機場效電晶體的主動層，利用遮罩式奈米轉印技術製作週期性奈米結構的PI (聚亞醯胺薄膜polyimide, 簡稱PI)修飾層。使用噴墨列印的方式製作半導體層，讓有機半導體有較長的時間排列分子結構，並利用遮罩定義半導體面積，使載子不會在多餘的區域內流竄，以降低漏電流，而獲得較佳之電特性。
實驗結果顯示，RR-P3HT在經過奈米結構的作用下，元件電特性將有所提升，相較於無壓印處理的PI元件，載子遷移率增加為3倍，且載子遷移率在平行結構與垂直結構方向上的比值，高達33倍。藉由原子力顯微鏡與掃描式電子顯微鏡，觀察出在奈米結構修飾層中，RR-P3HT有較佳的結晶規則程度與匯集於溝槽底部的現象，幫助電晶體電特性和載子遷移率異向性比的提升。在材料分析中，利用拉曼振動光譜分析結果指出，經奈米壓印處理的元件，RR-P3HT有較佳的分子排列方式。

關鍵字：有機場效電晶體、聚(3-己烷基噻吩)、週期性奈米結構。

In this study, we have successfully fabricated regioregular poly(3-hexylthiophene) (RR-P3HT)-based organic thin-films transistors (OTFTs) using polyimide (PI) with nanoimprinted grooves as the dielectrics layers to investigate the electronic transport behaviors. The contact-transferred and mask-embedded lithography technology was employed to form the PI-nanogrooves. Good orientation of the RR-P3HT polymer chains along the trench of the PI-nanogrooves was achieved by inkjet-printing the RR-P3HT on the PI-nanogrooves to result in high field-effect mobility OTFTs in which the field-effect is as high as 2.58×10-2 cm2/Vs. Especially, high mobility anisotropies (μ// /μ⊥), which is defined as the ratio of the carrier mobility along the PI-nanogrooves to that across the PI-nanogrooves, was obtained in the PI-nanogrooves OTFTs. In order to realize the properties of RR-P3HT films within the trench of the PI-nanogroove, atomic force microscopy, scanning electron microscope, and polarized micro-Raman spectroscopy were used to study the orientation of the RR-P3HT polymer chains.

Keywords: Organic thin film transistors, P3HT, Polyimide, Nanoimprint lithography technology, Micro-Raman.

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