抄録
The tensile strength and fracture of the polar and non-polar interfaces of the {122}Σ=9 tilt boundary in cubic SiC have been examined through the behavior of electrons and atoms using the ab initio tensile tests. The strength of these interfaces is very large because of reconstructed interfacial bonds. However, the interfacial C-C and Si-Si bonds have serious effects. For the non-polar interface with both C-C and Si-Si bonds, the fracture starts at the back Si-C bond of the C-C bond because of local stress concentration, and the fracture proceeds rather continuously. The P-type polar interface with Si-Si bonds has larger tensile strength with no remarkable local stress concentration because of highly symmetric configuration, and the fracture occurs rather catastrophically. There exists the general critical bond stretching for the Si-C bond breaking.
