本論文運用多種金屬如：鋁、鉿、鉭、鈦、鋯與銦氧化鍚（ITO）等在玻璃基板上作為閘極電極，以五環素（pentacene）為主動層所架構而成的有機薄膜電晶體‧藉由濺鍍而形成的閘極電極為基板而後覆蓋一層介電層 PVP（poly(4-vinylphenol)）與有著同樣閘極電極與一層介電層而二者之間插入一層極薄的氟化鋰(LiF)來比較，並探討其帶來的影響‧由於五環素仍舊是現今有機薄膜電晶體 p-type半導體的首選，因此將其作為此次實驗的主動層，並且採用容易製程的PVP作為此實驗的介電層，能夠藉由旋轉塗佈的方式為其一大特色‧
經由實驗結果發現金屬閘極, 例如鉿、鋯、鉭、鋁、鈦和ITO，以超薄的LiF為緩衝層在五環素為主動層所架構而成的有機薄膜電晶體，可明顯地提高電流、移動率和開關比率。由結果顯示得知，插入一層LiF在介電層之間和閘極電極能夠使表面粗糙度減少進而增加五環素的顆粒大小。 這歸因於一部分改進表面的表現。 在此，我們將LiF成膜應用於閘極電極與介電層之間，當氟化鋰薄膜為10埃時發現電流開關比 (10３) 有相當明顯的改進。金屬閘極電極在玻璃基板上與LiF能成功地整合成一金屬閘極電極的五環素薄膜電晶體。 相較於所有使用的金屬中， 對有機薄膜電晶體而言，ITO閘極電極俱有最高的功函數，顯示了最佳的電晶體特性。

Various metal gate electrodes, including aluminum (Al), hafnium (Hf), tantalum (Ta), titanium (Ti), zirconium (Zr), and other materials such as Indium Tin Oxide (ITO) on glass substrates, were applied to the fabrication of pentacene-based organic thin film transistors. By sputtering deposition on substrates, the metal gate electrodes have poly (4-vinyl phenol) (PVP) as insulator layers over substrate. When compared with the metal gate electrodes with an ultra-thin lithium fluoride films as substrate, this group of electrodes also had an insulator layer that generated effects. Subsequently, the pentacene was primarily selected in p-type organic thin-film transistors. For this reason, the pentacene served as the active layer, while the PVP served as an insulator layer that was easily manufactured for use in spinning and coated in this experiment.
It has been found that gate metals such as Hf, Zr, Ta, Al, Ti, and ITO, with an ultra-thin LiF buffer layer for pentacene-based OTFTs, can enhance the drain current, mobility, and on/off ratio significantly. As the results showed, the inserted LiF layer between the dielectric and gate electrode could result in decrease of the surface roughness and increase of grain size of pentacene film. This is attributed in part to improve device performance. Here, we deposit an ultra-thin LiF film between gate electrode and dielectric layer in pentacene-based OTFTs. The on/off current ratio (up to 103) is obviously improved as thickness of the LiF film is approximately 5.0 nm. The metal gate electrodes on the glass substrate with LiF could be successfully integrated into a metal-gated pentacene TFT. Compared with the metals used in the study, the ITO gate electrode, which had the highest work function for OTFTs, showed the best transistor performance.

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