Silicon has been used as semiconductor devices. It is well known that silicon shows a sharp brittle-ductile transition and that silicon is a brittle material at the operative temperature of a device. Hence, it is important to understand fracture behavior to improve the reliability of a device.
Because the surface energy, γs is considered to affect the fracture behavior of a brittle material, it is important to investigate the crystal orientation dependence of γs just after fracture in order to clarify the details of fracture mechanism. This study was carried out to clarify systematically the crystal orientation dependence of γs in silicon by molecular dynamics calculation. And it is also carried out to investigate the crystal orientation dependence of γs after 1098 K annealing and it was compared with γs just after fracture.
It is revealed that γs of (111) plane has the minimum value. This fact agrees with the experimental fact that cleavage plane of Si is {111}. It is also found that γs after 1098 K annealing is lower than that just after fracture. It is concluded that the decrease in γs was brought about by the reconstruction of the atoms.
