藉由在通道材料內添加奈米碳管以修改有機薄膜電晶體之光電特性

Modifying the Electrical and Optical Properties of Organic Thin Film Transistors by Adding the Carbon Nanotubes Inside the Channel Material

蔡華倫(Hua-Lun Tsai)

指導教授 ： 魏拯華

健行科技大學/電資學院/電子工程所/碩士(2009年)

摘要

為了製造出可彎曲的太陽能電池，許多以有機為基礎的材料在文獻中被提議，並且P3HT和C60衍生物PCBM的組合是最普遍的有效材料。然而，因為這材料有較低的遷移率，且由於採低成本的製程技術，所製造出的有機元件是屬於長通道，在於OTFTs 的電特性和光學反應之研究中仍然是欠缺的。在這報告中，我們添加一些奈米碳管在主動層內，並且有效的調配P3HT、PCBM和CNTs的比例，以減少 OTFTs 的有效通道長度。
在我們的研究中，將元件製作於PET塑膠基板之上，且製程溫度小於100oC。為了考量安全問題，我們選擇以甲苯當調配P3HT、PCBM和CNTs 的溶劑，並且調配出P3HT、PCBM和CNTs 之間的最佳比例為1 : 0 : 1。為了收集元件電流的資訊，我們設計一個堆疊型結構，元件上的源極/汲極電極是雙重的。在一個OTFT元件中，我們可以記錄上端或下端接觸結構的I-V特性曲線。對於光學反應，元件的垂直與橫向結構之電流變化也被紀錄，在徹底的研究這些數據資料後，我們可以找到奈米碳管在以有機為基礎上的影響。

關鍵字

奈米碳管 ； P3HT ； PCBM ； 堆疊型結構 ； 包覆式電極結構

並列摘要

To fabricate the flexible solar cells, the many organic-base materials are proposed in the literature and the combination of P3HT and C60 derivate PCBM is the most popular active material. However, because this material has a lower mobility and the channel length of organic devices which fabricated by the low-cost print technology is long, the electrical properties and optical responses of OTFTs are still poor. In this report, we add some CNT ropes inside the active layer and it will reduce the effective channel length of the OTFTs by optimizing the ratio between P3HT, PCBM and CNTs.
In our study, the device is fabricated on the PET substrate and the process temperature is less than 100oC. Considering the safety issue, we chose the toluene as the solvent of the P3HT, PCBM and CNTs and the optimal ratio between P3HT, PCBM and CNTs is the 4:2:1. To collect the information of the device’s current flow, we design a stack-type, double source/drain electrodes in the device. In one OTFT, we can record the I-V curves of OTFTs with the top-contact or bottom-contact configuration. For the optical response, the current changes of the devices with vertical and lateral structures are also recorded. After studying these data thoroughly, we can find the effect of the CNT ropes in the organic-base devices.

並列關鍵字

Carbon nanotube ； P3HT ； PCBM ； Stack-type electrode structure ； Embedded electrode structure

參考文獻

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Vol.363, pp. 603-605, 1993

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[4]. E. W. Wong, P. E. Sheehan, and C. M. Lieber, “Nanobeam mechanics: elasticity, strength and toughness of nanorods and nanotubes”, Science, Vol. 227, pp. 1971-1975, 1997.