Evolution of atoms with special coordination number in β-SiC with temperature

The characteristics and mechanisms of evolution of Si and C atoms with different coordination number were studied using molecular dynamics and molecular static. Relaxation energy of these systems and the displacement of these special atoms from their original positions have been investigated. The results showed that some of these special Si atoms moved away from their lattice sites and may become Si interstitial atoms at 300 K. As temperature increased, more intrinsic defects were detected. In the case of the one-coordinated C atom, this atom did not move away from its lattice site until 600 K, turning into a C interstitial atom. Then it became a C_Si antisite after 1200 K. In general, the relaxation energies and the displacement decrease with increasing coordination number. The differences between special Si and the equivalent special C systems strongly depend on the temperature.