1998 Fiscal Year Final Research Report Summary
Non-equilibrium phase formation by 3MV electron irradiation
| Project/Area Number |
09450237
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Physical properties of metals
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| Research Institution | Osaka University |
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Principal Investigator |
MORI Hirotaro Research Center for Ultra-High Voltage., 超高圧電子顕微鏡センター, 教授 (10024366)
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| Co-Investigator(Kenkyū-buntansha) |
YASUDA Hidehiro Electron Microscopy, Osaka University, Professor, 超高圧電子顕微鏡センター, 助手 (60210259)
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| Project Period (FY) |
1997 – 1998
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| Keywords | high energy electron beam / radiation effect / non-equilibrium phase / high-voltage electron microscope / semiconducting compaund |
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| Research Abstract |
Single crystals of Ill-V semiconductor compounds such as GaAs, GaSb and InAswere irradiated with 2 MeV electrons in a ultra-high voltage electron microscope. Electron irradiation first induces chemical disordering and with continued irradiation topological disordering sets in. The chemical disordering becomes more difficult to occur with increasing irradiation temperature and as a result of this the topological disordering is completely suppressed. The topologically- and chemically-disordered phases formed at low temperatures become unstable at 300 K, and as a result change into the chemically-disordered and ordered phases, respectively. In the zincblende structure, the charge distribution is unbalanced and the lattice is distorted with increasing the degree of chemical disorder. It is considered that the crystalline state transforms to the topologically-disordered states (i.e., an amorphous state) to relax the instability of chemical bonds.
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