Atomistic simulation on indented defects in silicon

Silicon is known as one of the widely used materials in electronic fields for its excellent semiconductive characteristics. However, these characteristics are vulnerable to internal defects, which randomly exist in any materials. In the present study, defects in single crystalline silicon thin film were investigated by atomistic simulation of nano-indentation at zero temperature. The Tersoff potential and the spherical indenter were applied to the model of silicon. The symmetric axis parameter method is novelly proposed to identify defects in the diamond cubic structure. Under the nanoindentation condition, the ring slip appears close to the indentation region on the free surface and propagates along with [110]/(111). The dislocation is initiated closely to the ring slip and emitted on the (111) plane by the dissociation into two partial dislocations. It was found that the symmetric axis parameter method successfully separated the perfect dislocations, the partial dislocations and the stacking fault from perfect structure, i.e., diamond cubic structure, even though it was not able to distinguish between glide set and shuffle set dislocations.