高效能下接觸式傳電子型有機薄膜電晶體

Abstract

本論文主要以有機合成的方法，藉由改良有機小分子的化學結構，進一步開發出適合於下接觸式電極元件結構的傳電子型有機半導體，所合成出的有機材料為 naphthalenetetracarboxylic diimide（NTCDI）為主的衍生物。而本論文所使用的有機薄膜電晶體，結構組成主要為：玻璃為元件的基板，ITO作為閘極，元件的介電層為二氧化矽。而電晶體的源極跟汲極，依本實驗的設計，分別採用了ITO、Mo、MoW三種不同功函數的金屬電極。將本實驗室合成出的有機材料，應用於下接觸式元件結構的有機薄膜電晶體，所得到的電子傳輸速率為0.01~0.03 cm2 V-1 s-1，並且此元件是可穩定於一般大器條件下操作。 為了更深入研究有機化合物的化學結構與元件穩定的相關特性，本實驗室將有機分子以緩慢成長的方式，將化合物成長出單晶的形式，藉由X光單晶繞射儀的分析得到分子確實排列的狀態，研究得到化學結構中含有氟化的取代基會造成分子與分子間更緊密的排列，也是此類化合物能在空氣下穩定的緣故。

In our studies, we try to modify chemical structures which can be useful applied in bottom-contact OTFTs. Naphthalenetetracarboxylic diimide-bsaed n-type organic semiconductors have been synthesized and a high mobility of ca. 0.01-0.03 cm2 V-1 s-1 was measured through bottom-contact devices in air. In the fabrication of our device, glass was used as the substrate, tin indium oxide (ITO) was the gate electrode, and silicon dioxide was the dielectric layer. In addition, we would like to realize that relations between the organic semiconductor and metal contact. Three different metals, ITO, molybdenum (Mo), and molybdenum-tungsten (MoW) were used as source/drain electrodes. Moreover, we also interested in single structures of our synthetic organic materials. Single crystals were grown, by a solvent-evaporation method, from a N,N-Dimethylacetamine. Molecules that are constructed via the electron-withdrawing groups would effectively help n-type organic materials to resist oxygen and moisture.