Defect accumulation in silicon carbide has been simulated by molecular dynamics using a Brenner-type potential connected smoothly to the Ziegler-Biersack-Littmark potential. Displacement damage in 3C-SiC, which is known to consist of point defects, vacancy and interstitial clusters and anti-site defects, was modelled by introducing random displacements in the Si or C sublattice. SiC was amorphized by Si displacements at a damage level corresponding to 0.15 displacements per atom (dpa) and by C displacements at 0.25 dpa. In both cases, the damage consists of Si and C Frenkel pairs as well as anti-site defects. The results provide evidence that SiC can be amorphized by displacing C atoms exclusively and suggest that short-range disorder provides the driving force for amorphization of SiC.
Revised: July 13, 2011 |
Published: April 5, 2004
Citation
Devanathan R., F. Gao, and W.J. Weber. 2004.Molecular Dynamics Simulation of Point Defect Accumulation in 3C-SiC. In Radiation Effects and Ion Beam Processing of Materials, Materials Research Society Symposium Proceedings held December 1-5, 2003, Boston, Massachusetts, edited by LM Wang, R Fromknecht, LL Snead, DF Downey and H Takahashi, 792, 479-484, Paper No. R4.1. Warrendale, Pennsylvania:Materials Research Society.PNNL-SA-40161.