以溶液方式成長親水性蒽衍生物半導體層用以製作選擇性有機薄膜電晶體

Selective Growth of Hydrophilic Anthracene Derivative as a Semiconductor Layer for Organic Thin Film Transistors via Solution-Process

王裕平(Yu-Ping Wang)

指導教授 ： 游萃蓉

國立清華大學/工學院/材料科學工程學系/碩士(2010年)

摘要

本研究合成一種具有羧酸基團 (carboxylic group) 的蒽 (anthracene) 衍生物 (anthracenetetracarboxylic acid，ATC) ，利用蒽衍生物材料主體的半導體性質，配合接上之羧酸基團的親水性，可使其在溶液環境中，選擇性成長在親水性表面改質後的二氧化矽 (SiO2) 閘極介電層上，且位於源極與汲極金屬之間，直接形成薄膜有機電晶體 (organic thin film transistor, OTFT) 。
　　為了達到未來應用於軟性電子低成本 (大面積塗佈印刷製作) 、低溫 (< 200 C) 之製程需求，及整合於未來積體電路產業之應用，本研究目標包括：第一，使有機半導體材料溶於毒性較低之溶劑中，大量使用此半導體材料與溶劑進行溶液製程時，不致破壞環境；第二，利用溶液製程，在一般大氣環境下使有機半導體薄膜選擇性成長在所需之位置，進一步節省成本。結果顯示，本研究成功的合成出含羧酸基團之蒽衍生物ATC，並利用其獨特之親水性，可於低毒性之親水性溶液環境中，選擇性成長有機半導體薄膜在親水性表面改質後的閘極介電層上，直接形成有機電晶體元件。此有機電晶體元件，可於一般大氣環境中量測其場效電晶體特性，其電子遷移率約為10-2 cm2V-1s-1，起始電壓約為-1.5 V，且開關電流比 (Ion/Ioff) 約為102，足以驗證此半導體材料ATC具備應用於未來軟性電子之可能性。

關鍵字

有機薄膜電晶體 ； 蒽衍生物 ； 選擇性成長 ； 溶液製程 ； 親水性

並列摘要

In this study, a novel anthracene derivative, anthracenetetracarboxylic acid (ATC) , was synthesized for organic thin film transistors (OTFTs) . This anthracene derivative, with the semiconductor properties of its core, was functionalized with carboxylic groups on 2, 3:6, 7 positions. With these hydrophilic carboxylic acid groups, ATC could be selective grown onto the gate dielectric layer (SiO2) modified with hydrophilic self-assembled monolayer (SAM), located between the source and drain metal, to form OTFTs via solution process directly.
In order to meet the requirements of low-cost (large-area printing production), low process temperature (<200 C) for future flexible electronics applications and the feasibility to be integrated with integrated circuits, this research is mainly focused on the following two major goals. Firstly, to avoid of the damages of the ecological environment, it is important to improve the solubility of organic semiconductors in environmentally friendly solvents. Secondly, via solution processes, selective growth of organic semiconductor film directly on the selected location is developed to reduce the process cost. Results showed that anthracene derivative ATC could be successfully synthesized. With its unique hydrophilic property and the use of environmentally friendly hydrophilic solvent, selective growth of ATC organic semiconductor film on gate dielectric modified with hydrophilic SAM was achieved to form OTFTs directly. Transistor characteristics of such OTFTs were measured in air, with a mobility of about 10-2 cm2V-1s-1, a threshold voltage of -1.5 V and an on/off current ratio about 102. Results above have demonstrated the feasibility of using solution-processed, hydrophilic organic semiconductor ATC for OTFTs fabrication and future flexible electronics application.

並列關鍵字

Organic Thin Film Transistor ； Anthracene Derivative ； Selective Growth ； Solution-process ； Hydrophilic

參考文獻

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