取代基對苯并二噻吩之有機場效電晶體效能的影響

Influences of Substituents on the Performance of Benzodithiophene-Based Organic Field Effect Transistors

劉怡姍(Yi-Shan Liu)

指導教授 ： 郭明裕

國立暨南國際大學/科技學院/應用化學系/碩士(2012年)

摘要

有機場效電晶體近年來應用日漸廣泛，雖然目前為止大多有不錯的電性，但是大多數的元件在空氣中不穩定，存放於自然環境下也會造成電性衰退，因此開發並研究可於空氣中穩定存放並操作之有機場效電晶體為本實驗目的。
本篇主要發展一系列苯并二噻吩分子，針對官能基為噻吩以及苯環分子為主要研究目標，並探討不同官能基成長出的薄膜對電性的影響，首先將官能基為噻吩的DT-BDT分子和官能基為苯環的D4-BDT分子，分別利用真空蒸鍍方式沉積於基板上，並用原子力顯微鏡、電性量測系統探討薄膜表面形貌及電性分析；接著再用電性較好，官能基為苯環的分子，接上不同長碳鏈探討。以側鏈為四個碳的D4-BDT、八個碳的D8-BDT、十二個碳的D12-BDT分子，分別將分子沉積於基板上，接著用原子力顯微鏡、X光繞射光譜儀、電性量測系統去探討薄膜形貌、分子排列情況以及電性效能分析，並比較不同基板溫度對電性的影響。最後實驗結果顯示，D8-BDT在基板溫度40 ℃時有最佳的載子傳輸率0.3 cm2V-1s-1，而經過ODTS修飾過的基板也同樣在基板溫度40 ℃時有最好的電性0.21 cm2V-1s-1；此外，經過ODTS修飾的基板之元件，在一般環境下置放一年後，其電性仍然沒有改變，穩定性勝過未經修飾的SiO2基板之元件。

關鍵字

有機場效電晶體 ； 苯并二噻吩分子 ； 基板溫度

並列摘要

Organic field effect transistors have been applied widely in recent years. Although most of the devices had good mobility, they still had unstable properties when devices stored in air, It is necessary to research and develop OFETs, which have good mobility and stable qualities.
In this study, we used phenyl- and thiophene- functional groups for this research, and then discussed the morphology and performances between the different functional groups. First, we deposited DT-BDT and D4-BDT on different devices, and probed into surface and mobility by atomic force microscope and I-V Parameter.
Based on the phenyl- functional group which has better mobility, we investigate the D4-BDT, D8-BDT, and D12-BDT comprised a pair of butyl, octyl, dodecyl chains, respectively. All these compounds are deposited on substrates, then analyze morphology, molecular order, electrical property by AFM, X-ray diffraction, and I-V Parameter. Finally, we compared the influences of substrate temperature and mobility. The experiment reveals that the D8-BDT electron mobility up to 0.3 cm2V-1s-1 at 40 ℃, and the devices which substrate was modified by ODTS exhibit 0.21 cm2V-1s-1 . Furthermore, the modified substrate stored in air has the same mobility after one year, the stability is greater than SiO2 substrate.

並列關鍵字

Organic Field-Thin Transistor ； Benzodithiophene ； Substrate Temperature

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