| Co-Investigator(Kenkyū-buntansha) |
KASUYA Atsuo Center for Interdisciplinary, Research, Tohoku University, professor, 学際科学国際高等研究センター, 教授 (10005986)
SUTO Shozo Tohoku University, Graduate school of Science, Tohoku University, Professor, 大学院理学研究科, 教授 (40171277)
山村 力 東北大学, 大学院・工学研究科, 教授 (80005363)
|
|---|
| Budget Amount *help |
¥3,400,000 (Direct Cost: ¥3,400,000)
Fiscal Year 2006: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2005: ¥2,900,000 (Direct Cost: ¥2,900,000)
|
|---|
| Research Abstract |
Recently, it has been reported that properties of non-stoichiometric titanium nitride compounds (TiN_y), such as electrical conductivity, diffusion barrier, wear resistance, etc. depend not only on chemical composition, but also on orientation relationships between TiN_y films and substrates. Therefore, much interest has been focused on atomistic growth processes of TiN_y films.In order to clarify the atomistic growth processes due to ion implantation and to control the orientation, in-situ observations by using transmission electron microscope and electron energy loss spectroscope have been carried out, along with composition analysis and with the characterization of electronic structure. TiN_y has epitaxially grown in N-implanted Ti films by nitriding both hcp-Ti and TiH_x., or only hcp-Ti with epitaxial orientations in as-deposited Ti films on NaC1 (001) substrates at room temperature or 250 ℃. The characterizations of electronic structure of Ti films before and after implantation indicate that octahedral sites of hcp-Ti with larger space have higher electron density, which leads to the invasion of implanted ions into the octahedral sites, and that the hcp-fcc transformation accompanied with the partial inheritance of atomic arrangement of hcp-Ti is induced by the shear in <01・0> direction on (00・1) plane promoted by the forming of strong covalent bonds mainly consisted of hybridized orbitals due to combination of Ti3d and N2p, and by the weakening of Ti-Ti bonds. In conclusion, atomistic epitaxial growth processes of Ti compound films by ion implantation have been clarified by the approach of the detailed analysis of experimental results, combined with the characterization of electronic structure, which gives rise to a possibility to develop new functionalized Ti compound films with controlled orientations, for example, TiN_y diffusion barriers in Au/α-Sn systems, band-gap-controlled functionalized SiTi_xN_y systems.
|
