Accumulation and recovery of disorder on silicon and carbon sublattices inion-irradiated 6H-SiC

Irradiation experiments have been performed at 100, 170 and 300 K for 6H-Si C single crystals using Au2+ and He+ ions over a range of fluences. The evo lution of disorder on both the Si and C sublattices has been simultaneously investigated using 0.94 MeV D+ Rutherford backscattering spectrometry (RBS ) in combination with C-12(d,p) nuclear reaction analysis (NRA) in a (0 0 0 1) axial channeling geometry. At low doses, a higher rate of C disordering is observed, which is consistent with molecular dynamics simulations that suggest a smaller threshold displacement energy on the C sublattice. At hig her doses for He+ irradiation, the C disordering appears to increase less r apidly than the Si disordering. Three distinct recovery stages are observed on both the Si and C sublattices in the Au2+-irradiated 6H-SiC. However, c omplete recovery of irradiation-induced disorder does not occur during isoc hronal annealing at temperatures up to 970 K. (C) 2001 Elsevier Science B.V . All rights reserved.