Raman spectroscopy has been used to identify defective bonding in neon and
silicon ion irradiated single crystals of 6H-SiC. Observable differences exist
in the C-C bonding region corresponding to different defect structures for neon
and silicon ion implantations. Raman spectra of ion irradiated SiC show less
tensile strain than neutron irradiations, explained by a residual compressive
stress caused by the swelling constrained by the undamaged substrate. Evidence
of oxidation during high temperature ion implantation is observed as C-O and
Si-O Raman signals. Annealing irradiated SiC while acquiring Raman spectra
shows rapid recovery of Si-C bonding, but not a complete recovery of the
unirradiated structure. Annealing irradiated SiC causes surface oxidation where
unirradiated SiC does not oxidise. Comparisons are made to the apparent
radiation resistance of diamond and silicon which have similar crystal
structures, but are monatomic, leading to the suggestion that chemical defects
are responsible for increased radiation damage in SiC.Comment: 24 pages, 8 figure