Project/Area Number |
14550021
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
表面界面物性
|
Research Institution | University of Tsukuba |
Principal Investigator |
OSHIYAMA Atsushi University of Tsukuba, Institute of Physics, Professor, 物理学系, 教授 (80143361)
|
Co-Investigator(Kenkyū-buntansha) |
OTANI Minoru The University of Tokyo, Institute for Solid State Physics, Research Associate, 物性研究所, 助手 (50334040)
|
Project Period (FY) |
2002 – 2003
|
Project Status |
Completed (Fiscal Year 2003)
|
Budget Amount *help |
¥4,000,000 (Direct Cost: ¥4,000,000)
Fiscal Year 2003: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 2002: ¥2,300,000 (Direct Cost: ¥2,300,000)
|
Keywords | Nano-Science / Density Functional Theory / First-Principle Molecular Dynamics / Silicon / Nitride Semiconductor / Nanotube / Nanowire / Si / SiO_2 / コンダクタンス |
Research Abstract |
Our accomplishments are classified into 2 groups : (1)Clarification and prediction of phenomena in materials that are important in current technology, and (2)prediction of new properties and functions of nano-materials that may constitute basis of future technology. In the first group, the followings are clarified : 1.Diffusion mechanisms of Boron impurities in SiO2 : B takes the several charge states in SiO2, and it is clarified that diffusion pathways and corresponding activation energies are sensitive to the charge state. 2.Si nano-crystal is forged by femto-second laser irradiation of SiO2.Difference in diffusion coefficients of the 2 elements allows the formation of the Si crystal below the melting temperature 3.The energy gap of InN is found to be less than 1 eV, thus opening the possibility of nitride semiconductors with a wide range of wavelengths in optoelectronic devices. 4.ZrB2 is shown to be a good substrate for GaN good-quality films. In the second group, we have found the followings : 1.Hydrogen-covered Si becomes a nanoscale magnet by removing H atoms in a controlled way and hereby forming nanoscale dangling-bond networks 2.Carbon nanotubes with zigzag edges exhibit a variety of magnetic properties depending on their tube radii 3.Semiconducting carbon nanotubes become metallic when 2 different tubes become a double-wall nanotube, depending on the ratio of the radii of the two tubes. 4.In tubes and fullerenes, internal space plays a crucial role in determining electronic structures near Fermi level. 5.In Al atom wires, the conductance occasionally increases upon stretching the wire. This is characteristic to atom wires consisting of sp-orbital elements.
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