非對稱性苝二醯亞胺材料製成可於空氣中穩定操作之N型有機場效電晶體

為了開發出更具空氣穩定性的N-type材料運用於有機場效電晶體中，本篇論文便設計出一系列具不對稱結構的苝二醯亞胺衍生物(PBIs)，分別以含氟與未含氟之烷基修飾分子兩端的醯亞胺(Imides)，並針對化合物的電子親和力、固態堆疊以及熱穩定性…等進行探討。同時也將所合成的PBIs分子以不同條件裝置成場效電晶體元件中，並利用X光繞射實驗(XRD)及原子力顯微鏡(AFM)探測半導體層的結晶堆疊與薄膜型態，以探討分子結構與製程條件對元件效能的影響。實驗結果顯示，三組PBIs衍生物皆具有高於水氣的還原電位而符合具空氣中穩定性的條件。將三組化合物分別裝置於元件後，經由XRD與AFM的探測可發現沉積在125 ℃且經OTS與ODTS修飾的基板之半導體層普遍會有較好的薄膜型態與電性表現。整體來說是以C4H-PBI-C4F與C8H-PBI-C4F平均有較佳的元件效能，載子遷移率最高皆可達10-2 cm2V-1s-1，開關電流比則是以C4H-PBI-C4F較高可達104。三組元件的電性皆可直接在空氣中測得，而C4H-PBI-C4F與C4H-PBI-C8F元件存放於空氣中12個月後不但載子遷移率未衰退，且開關電流比更出現了提高的現象；類似的情況也可在C8H-PBI-C4F元件觀察到，證明了三組材料優異的電性與穩定性。

關鍵字

空氣穩定性； N-type材料；有機場效電晶體；苝二醯亞胺衍生物

並列摘要

In order to develop more air-stable N-type materials applied to Organic Field-effect Transistors(OFETs), we have designed a series of asymmetric Perylene Bisimides (PBIs) with molecule’s two imides modified by alkyl chains and perfluoro-alkyl chains separately, then investigated their electron affinities、stacks in solid state and thermo-stability, etc. Furthermore, we also fabricated three new PBIs on OFET devices under various conditions, used XRD and AFM to probe crystalline packing or film morphology of semiconductors. After experiments and measurements, we found that all three compounds have higher reduction potentials than H2O(-0.658 V vs SCE), that’s a desirable quality for air-stable N-type materials. As for devices, through XRD and AFM we have observed that better crystalline or morphology of semiconductors generally formed when materials deposited on OTS- or ODTS-pretreated substrates under 125 ℃. In rough, C4H-PBI-C4F and C8H-PBI-C4F have better device performance, both two have highest carrier mobility up to 10-2 cm2V-1s-1 and the best Ion/off 104 of C4H-PBI-C4F devices. Basically, most devices fabricated with three PBIs could exhibit good electric performance under air. Moreover, after 12 months stored in air, the carrier mobility of C4H-PBI-C4F or C4H-PBI-C8F devices have not declined, but both their Ion/off ascended. Similar phenomenon also appeared on C8H-PBI-C4F devices, which had proven excellent OFET performance and stability of three materials under air.