本論文研究以五環素(Pentacene)為主動層並利用奈米轉印技術(Nanoimprinting)製作週期性溝槽結構的介電層，五環素在磊晶時因週期性溝槽的影響，磊晶成長出五環素塊材結構較大的半導體層。實驗中透過四個不同週期(800 nm、1200 nm、1600 nm、2400 nm)的週期性溝槽結構介電層，去探討五環素磊晶為主動層之有機場效電晶體的差異，由原子力電子顯微鏡(Atomic Force Microscope)觀察出在奈米溝槽結構週期為1600 nm時五環素有較佳結晶結構。電性量測發現，載子移動率(Mobility)在電場平行週期性溝槽結構與垂直週期性溝槽介電層結構的異向性比在週期為1600 nm時達到最高，且較其他不同配向方法之研究效果更佳，可達200倍；而不同週期溝槽元件的電性量測，也得到在週期性溝槽結構為1600 nm時，載子移動率亦達到最高為2.64 cm2/Vs。在材料分析上，偏極化微拉曼激發光譜分析結果指出，在奈米結構修飾層週期為1600 nm時，其主動層的五環素分子排列的次序最為一致，此結果證明了為何在週期為1600 nm的修飾層上會有最佳的載子移動率。

Pentacene is a very popular material to be the semiconductor layer on organic-thin-film-transistors (OTFT) because of its high operating performance in recently decades. In this experiment, we constructed a periodic nanogroove dielectric layer by hot embossing nanoimprint lithography in organic thin film transistors to achieve high field-effect mobility and ultrahigh anisotropic ratio of the mobility (> 200) defined as the mobility ratio of parallel nanogroove to perpendicular nanogroove. There were four periods, including 800, 1200, 1600, and 2400 nm, of nanogrooves dielectric to be constructed. In the discussion, the OTFT with 1600 nm nanogroove dielectric layer had the highest field-effect mobility of 2.64 cm2/Vs analyzed from the transfer curve in which the direction of electric field between source and drain is parallel to that of the nanogrooves. It also had the highest anisotropic ratio of mobility 203. Micro-Raman analyses indicated that the OTFT with 1600 nm nanogroove dielectric had the best molecular ordering for pentacene film to result in the best operating performance. Atomic Force Microscopes (AFM) also convinced this result of the most uniform and biggest grains on 1600 nm nanogroove dielectric.

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