本篇論文著重於利用五環素來製作有機薄膜電晶體。本篇論文與一般人不同之處就是採用光激發化學氣相沉積法來成長二氧化矽，而這層二氧化矽在我們元件裡是作為介電層之用。這可能是第一次將光激發化學氣相沉積製作的二氧化係用於有機薄膜電晶體的元件裡。理論上，用化學氣象沉積的二氧化矽品質應該是不錯，但是事實卻不是如此。我們所製作出來的元件特性普遍不好，我們推論有可能是二氧化系的均勻度不好所致。
首先，我們使用X光繞射量測我們所成長的五環素薄膜品質。我們由X光繞射所得的資料顯示:五環素薄膜有形成十分整齊的結構；此外我們利用公式可推得晶格常數約為15.3 Å，這樣的結果與其他人的實驗結果及文獻是十分相近。
再者，我們製作出不同通道長度的元件。我們從電流與電壓的特性發現：具有較長通道的元件，其電流明顯比通道較短的元件小。在這個實驗中，我們也利用傳統的金氧半場效電晶體的電流公式萃取出等效的載子移動率。其中，我們得到最好的載子移動率為3.16×10-5 cm-2*V-1*s-1 。
最後，我們探討閘極偏壓與有效載子移動率的關係。在這個實驗之中我們發現一個有趣的現象。當閘極偏壓在0伏特到-15伏特之間，有效的載子移動率會隨電壓下降而變小；另外在閘極偏壓小於-15伏特之後，有效的載子移動率則呈現趨於定值的現象。關於這個有趣的現象，我們採用了不同電流路徑及缺陷在大電場作用下被載子填滿的效應來解釋這個現象。

In this thesis, we focused on the pentacene-based organic thin-film transistors. SiO2 was adopted, which was deposited by PhotoCVD to be the insulator layer. This might be the first time to use Photo-CVD fabricated SiO2 in the OTFT devices. In theory, the quality of SiO2 would be better that was made from CVD system. But the results of our experiments were poorer than other’s results due to the nonuniformity of silicon dioxide.
First, the quality of the Pentacene thin film was determined with the X-ray diffraction measurements. From the data of XRD, it was discovered that our organic thin films had very order structures. Using the equation, the plane spacing of Pentacene thin films was about 15.3 Å. This result was consisting with other’s experiments and literatures.
Second, the devices with different channel length were fabricated. From the current-voltage characteristics, it could be found that the devices with largerchannel length had the smaller the effective mobility. The best effective mobility we obtained in this experiment was 3.16×10-5 cm-2*V-1*s-1.
Finally, the relation between the gate bias and effective mobility was discussed. In this experiment, a very interesting phenomenon was found. The effective mobility would reduce under the gate bias which was from 0 V to –15V. Then, the effective would tend to be constant when the gate bias was more negative than –15V. The different current path and trap filling were used to explain this phenomenon.

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