導電性高分子聚合物/有機材料及自我組裝單分子層在空間電荷限制電晶體中的應用

Abstract

軟性電子與顯示技術是新世代電子技術領域之重要方向，有機電晶體更是因為低製作成本、易於大面積製作等優點而被許多專家學者廣泛研究討論。傳統之有機場效電晶體具有在同一平面的源極與汲極，屬於水平結構，因其難以縮短通道長度及受限於高分子材料之低載子遷移率等原因，導致高操作電壓及低輸出電流等缺點。所以有人提出以膜厚控制通道長度，但是卻因為製程因素，大部分提高了輸出電流卻犧牲了開關比。有鑒於此，本論文將介紹一種具有製程簡單、低操作電壓、輸出電流大特性之垂直式有機電晶體。 本論文首先討論具有不同主動層有機材料的空間電荷限制電晶體，並探討其工作原理與元件特性。目前高分子空間電荷限制電晶體當操作電壓是1伏特的時候最大輸出電流密度是0.136mA/cm2，開關比為24310，電流增益約為104。在比較不同主動層的元件時發現到主動層的形態會造成漏電現象。接著將介紹一些自我組裝單分子層的化學結構還有操作原理。最後將討論自我組裝單分子層應用在製作元件中減少製作時間或是增加輸出電流的成果。

Polymer transistors have been studied extensively due to their applications on low-cost large area transistors arrays or on flexible electrons. Conventional polymer filed-effect transistor (FET) is a horizontal device with source and drain electrodes in the same plane. Low mobility conjugated polymers and long channel length limit the characteristics of polymer FET, and thus polymer FET usually exhibits high operation voltage and low operation frequency. In view of these limitations, this paper will introduce various vertical organic transistors; the channel length is determined by the total thickness of the organic semiconductor layer between source and drain. Even high turn-on current has been obtained low on/off ratio and sophisticated vertical fabrication procedures limit its following development. Specifically, on/off ratio of most vertical transistors are as low as a few hundreds. In this thesis we will discuss with different active layer materials of organic space-charge-limited transistors, then introduce operating mechanism and of characteristics the devices. So far, output current density of space-charge-limited transistor is about 0.136 mA/cm2 at operating voltage 1V, on/off ratio is 24310, and current gain is around 104. In comparing the device of different active layer was found that the morphology of active layer will cause leakage phenomenon. Then it will introduce self-assembled monolayer’s chemical structure and the principle of operation. Finally, discussion of self-assembled monolayer used to reduce the production time or increase output current for the devices.