Kobayashi S, Nishikawa T, Takenobu T, Mori S, Shimoda T, Mitani T, Shimotani H, Yoshimoto N, Ogawa S, Iwasa Y
Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
Nat Mater. 2004 May;3(5):317-22. doi: 10.1038/nmat1105. Epub 2004 Apr 4.
Organic thin-film transistors are attracting a great deal of attention due to the relatively high field-effect mobility in several organic materials. In these organic semiconductors, however, researchers have not established a reliable method of doping at a very low density level, although this has been crucial for the technological development of inorganic semiconductors. In the field-effect device structures, the conduction channel exists at the interface between organic thin films and SiO(2) gate insulators. Here, we discuss a new technique that enables us to control the charge density in the channel by using organosilane self-assembled monolayers (SAMs) on SiO(2) gate insulators. SAMs with fluorine and amino groups have been shown to accumulate holes and electrons, respectively, in the transistor channel: these properties are understood in terms of the effects of electric dipoles of the SAMs molecules, and weak charge transfer between organic films and SAMs.
由于几种有机材料中相对较高的场效应迁移率，有机薄膜晶体管正吸引着大量关注。然而，在这些有机半导体中，尽管掺杂对于无机半导体的技术发展至关重要，但研究人员尚未建立一种在非常低的密度水平下进行可靠掺杂的方法。在场效应器件结构中，导电沟道存在于有机薄膜与SiO₂栅极绝缘体之间的界面处。在此，我们讨论一种新技术，该技术使我们能够通过在SiO₂栅极绝缘体上使用有机硅烷自组装单分子层（SAMs）来控制沟道中的电荷密度。已表明带有氟和氨基的SAMs分别在晶体管沟道中积累空穴和电子：这些特性可根据SAMs分子的电偶极子效应以及有机薄膜与SAMs之间的弱电荷转移来理解。
