Project/Area Number |
13440110
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
固体物性Ⅱ(磁性・金属・低温)
|
Research Institution | Tohoku University |
Principal Investigator |
IWASA Yoshihiro Tohoku University, Institute for Materials Research, Professor, 金属材料研究所, 教授 (20184864)
|
Co-Investigator(Kenkyū-buntansha) |
KOBAYASHI Shinichiro Tohoku University, Institute for Materials Research, Research Associate, 金属材料研究所, 助手 (20361173)
TAHENOBU Taishi Tohoku University, Institute for Materials Research, Research Associate, 金属材料研究所, 助手 (70343035)
TAGUCHI Yasujiro Tohoku University, Institute for Materials Research, Associate Professor, 金属材料研究所, 助教授 (70301132)
IZUMI Akira Kyushu Institute of Technology, Faculty of Engineering, Associate Professor, 工学部, 助教授 (30223043)
|
Project Period (FY) |
2001 – 2003
|
Project Status |
Completed (Fiscal Year 2003)
|
Budget Amount *help |
¥17,000,000 (Direct Cost: ¥17,000,000)
Fiscal Year 2003: ¥4,100,000 (Direct Cost: ¥4,100,000)
Fiscal Year 2002: ¥4,100,000 (Direct Cost: ¥4,100,000)
Fiscal Year 2001: ¥8,800,000 (Direct Cost: ¥8,800,000)
|
Keywords | Fullerene / Field Effect Transistor / Self-Assembled Monolayer / Interface Modification / Carrier Injection / Carrier Control / Fullerene Polymer / Rare Earth Doped Fullerenes / カーボンナノチューブ / ドーピング / インターカレーション / ネットワーク構造 / 強磁性 / 金属内包フラーレン / 分子回転 / 誘電異常 / MBE |
Research Abstract |
Organic thin film transistors (TFTs) 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 in a very low density level, although this has been crucial for technology development of inorganic semiconductors. Here we discuss a new technique that enables us to control the charge density at the channel by employing 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. In-situ high pressure x-ray diffraction experiments and the first-principle local density functional calculations revealed that a transformation from the two-dimensional (2D) tetragonal C60 polymer to a three-dimensional (3D) polymer takes place via. a highly anisotropic compression of C60 molecules along the c-axis, as an irreversible first-order order transformation above 20 GPa. In the 3D polymer phase, the 2+2 bonds remains in the 2D plane, while neighboring layers are connected by the 3+3 bonds. The bulk modulus of the 3D polymer was 407 GPa, being slightly smaller than that of diamond.
|