近年來，有機顯示器成為市場上的前瞻技術，利用有機發光二極體和有機薄膜電晶體已經可以製作出低成本、可彎曲、全彩的平面顯示器。本論文以“bottom contact＂的結構， SiO2 為絕緣層，利用蒸鍍的方式成長有機薄膜，成功地製作出以Pentacene 為有機材料的有機薄膜電晶體。
在第三章當中，我們先研究元件通道尺寸大小對有機薄膜電晶體電特性的影響。我們製作不同尺寸的元件作比較，發現當元件通道長度愈長、通道寬度愈短，其載子移動率較高。我們再利用鉑、鈀、鎳來當作有機薄膜電晶體之源極和汲極的電極材料，發現用鉑當電極材料得到的特性較好，這是由於功函數較大的材料比較能夠和 Pentacene 形成較佳的歐姆接觸。
在第四章，我們把有機薄膜電晶體放在大氣環境下，觀察元件劣化的情況。我們發現元件臨界電壓會偏移 (Threshold Voltage shift) 、漏電流 (leakage current) 會增加、導通電流 (On Current) 會下降，這是由於大氣中的水氣會造成有機薄膜電晶體特性的衰減。

Recently active matrix organic light-emitting diodes (AMOLEDs) become the most advanced technique on the FPD market. Using organic light-emitting diodes (OLEDs) and organic thin film transistors (OTFTs) can produce low-cost, flexible, full color. Flat panel- display in the dissertation, we use the “bottom contact” as the gate structure and SiO2 as gate insulator layer. Using the above structure, we have successfully fabricated Organic thin-film-transistor with Pentacene as the active layer.
In chapter 3, we have first studied the effect of channel dimension on the device characteristics. For various channel dimensions. The longer the channel length and the narrower the channel width, the larger the mobility. Secondly, we have investigated the effect of different source/drain metal on device performance. The metals of S/D electrode are (Platinum, Pt), (Palladium, Pd), (Nickel, Ni). It is found that among these metals, the (Platinum, Pt) as S/D electrode can result in the best performance due to the highest work function and the best ohmic contact between S/D metal and Pentacene.
In chapter 4, we stress organic thin film transistor in the atmosphere to observe the change of the device characteristics. We find that the increasing threshold voltage, decreasing on current and increasing leakage current with the stress duration. This is because that the humidity of atmosphere causes the performance degradation of the organic thin film transistor as a result of H2O molecule diffusing into the grain boundary of Pentacene.

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