Specimens of monocrystalline 4H-SiC were irradiated to 3 successively increasing ion fluences ranging from 7.2 x 1014 to 6.0 x 1016/cm2 (corresponding to the peak displacement damage of 1, 4 and 13dpa) with Ne and Xe ions respectively with the energy of 2.3MeV/amu. The irradiated specimens were subsequently annealed at 1173 and 1273K. The defect structure was investigated using transmission electron microscopy and a cross-sectional specimen preparation technique. The typical microstructures of the annealed specimens irradiated with Ne or Xe ions to high fluences were characterized by small gas bubbles in high concentration in the peak damage region and black dots and dislocation loops (located in the basal plane) in a shallower and broader depth region. Larger dislocation loops were observed in the Xe-ion irradiated specimen than in the Ne-ion irradiated specimen at the same peak damage level. The enhanced formation of dislocation loops in the case of Xe-ion irradiation was understandable by assuming stronger inclination of heavier inert-gas atoms to occupy substitute site in the peak damage region.

Defect Production in Silicon Carbide Irradiated with Ne and Xe Ions with Energy of 2.3MeV/amu. C.H.Zhang, Y.M.Sun, Y.Song, T.Shibayama, Y.F.Jin, L.H.Zhou: Nuclear Instruments and Methods in Physics Research B, 2007, 256[1], 243-7