Studies of Damage Accumulation in 4H Silicon Carbide by Ion-Channeling Techniques
Single crystal 4H-SiC was irradiated with 2 MeV Au ions at 165 K. Ion-induced defect configurations and damage accumulation were studied by ion-channeling techniques along the <0001>, > < 3 40 4 and > < 1 20 2 directions. A nonlinear dependence of damage accumulation is observed for both the Si and C sublattices along all three directions, and the relative disorder observed along the > < 3 40 4 and > < 1 20 2 directions is much higher than that along the <0001> direction. The damage accumulation can be described by a disorder accumulation model, which indicates that defect-stimulated amorphization is the primary amorphization mechanism in SiC, and the high disorder level for the large off-axis angles is attributed to particular defect configurations. Molecular dynamics (MD) simulations demonstrate that most single interstitial configurations are shielded by Si and C atoms on the lattice sites along the <0001> direction, which significantly reduces their contribution to the backscattering/reaction yield along the <0001> direction.
Z.Y. Zhong, H. Saka, T.H. Kim, E.A. Holm, Y.F. Han and X.S. Xie
Y. Zhang et al., "Studies of Damage Accumulation in 4H Silicon Carbide by Ion-Channeling Techniques", Materials Science Forum, Vols. 475-479, pp. 1341-1344, 2005