本研究目的在探討以溶液式的製程於軟性基板上製作有機薄膜電晶體之現象，初步以真空鍍膜的方式製作五環素有機薄膜電晶體並觀察其可靠度。為了要更進一步降低成本與大面積製造，我們使用噴墨印刷技術定義圖案並分析其可行性，然而，我們發現此製程非常容易受到表面粗糙度以及表面能的影響使得困難度增加，因而單純使用噴印式的絕緣層製作五環素有機薄膜電晶體，但是我們同時也萃取出噴印的最佳參數。經過以上的實驗結果評估，我們改用底部接觸的結構來實現全溶液-聚3-己基噻酚-薄膜電晶體，其絕緣層使用高分子，旋塗於不鏽鋼基板上，源極與汲極使用噴墨印刷定義，所有的製程均是常壓下製作，溫度均在150℃以下。最後，我們成功沿伸溶液式的製程在不同的基板上，也意味著全溶液式的有機薄膜電晶體是可行的。

In this work, the fabrication of solution-processed organic thin film transistors (OTFTs) on flexible substrates was investigated. In the preliminary study, vacuum deposition was used to the fabrication of pentacene-based OTFT to study the reliability. Furthermore, inkjet-printing technology to define patterns in order to reduce the production costs is conducted for feasibility analysis. However, the difficulty of inkjet-printing fabrication will be increased by worse adhesion between materials from rough surface roughness or mismatch of surface energy. Instead, an inkjet-printed insulator in pentacene-based OTFT was employed and the best parameters were extracted, respectively. After evaluating experimental results, bottom contact structure to realize all solution poly (3-hexythiophene) (P3HT) based organic thin film transistor was selected. The polymer insulator was spin-coated on the stainless steel substrate, and source/drain was defined by inkjet-printing. All the processes were operated in atmosphere ambient and below 150℃. Finally, extended solution-processed methods on various substrates were demonstrated. This means that the all solution-processed OTFTs are really feasible.

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