Local Structure of Ion-Bombarded α-SiC Analyzed by EXAFS
نویسندگان
چکیده
X-ray absorption spectroscopy on the Si k-edge was performed on a-Sic (6H) to monitor the evolution of the local structure around the Si atoms after ion bombardment. The samples were irradiated by 50 keV Na ions at fluences of 10" 10" ions/cma at a temperature of 80 K. EXAFS analysis clearly reveals that the hetero-atomic short range order of the crystalline matrix is almost completely conserved over the crystalline-to-amorphous transition as indicated by RBS-C. Further irradiation at higher fluences results in a change of the atomic coordination and formation of homonuclear Si-Si bonds.
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