Nomura Kenji, Ohta Hiromichi, Takagi Akihiro, Kamiya Toshio, Hirano Masahiro, Hosono Hideo
ERATO-SORST, JST, in Frontier Collaborative Research Center, Mail Box S2-13, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.
Nature. 2004 Nov 25;432(7016):488-92. doi: 10.1038/nature03090.
Transparent electronic devices formed on flexible substrates are expected to meet emerging technological demands where silicon-based electronics cannot provide a solution. Examples of active flexible applications include paper displays and wearable computers. So far, mainly flexible devices based on hydrogenated amorphous silicon (a-Si:H) and organic semiconductors have been investigated. However, the performance of these devices has been insufficient for use as transistors in practical computers and current-driven organic light-emitting diode displays. Fabricating high-performance devices is challenging, owing to a trade-off between processing temperature and device performance. Here, we propose to solve this problem by using a novel semiconducting material--namely, a transparent amorphous oxide semiconductor from the In-Ga-Zn-O system (a-IGZO)--for the active channel in transparent thin-film transistors (TTFTs). The a-IGZO is deposited on polyethylene terephthalate at room temperature and exhibits Hall effect mobilities exceeding 10 cm2 V(-1) s(-1), which is an order of magnitude larger than for hydrogenated amorphous silicon. TTFTs fabricated on polyethylene terephthalate sheets exhibit saturation mobilities of 6-9 cm2 V(-1) s(-1), and device characteristics are stable during repetitive bending of the TTFT sheet.
在柔性衬底上形成的透明电子器件有望满足硅基电子产品无法解决的新出现的技术需求。有源柔性应用的例子包括纸质显示器和可穿戴计算机。到目前为止，主要研究了基于氢化非晶硅（a-Si:H）和有机半导体的柔性器件。然而，这些器件的性能不足以用作实际计算机中的晶体管以及电流驱动的有机发光二极管显示器。由于加工温度和器件性能之间的权衡，制造高性能器件具有挑战性。在此，我们提议通过使用一种新型半导体材料——即来自In-Ga-Zn-O系统的透明非晶氧化物半导体（a-IGZO）——用于透明薄膜晶体管（TTFT）的有源沟道来解决这个问题。a-IGZO在室温下沉积在聚对苯二甲酸乙二酯上，表现出超过10 cm2 V(-1) s(-1)的霍尔效应迁移率，这比氢化非晶硅大一个数量级。在聚对苯二甲酸乙二酯片材上制造的TTFT表现出6 - 9 cm2 V(-1) s(-1)的饱和迁移率，并且在TTFT片材的重复弯曲过程中器件特性稳定。
