Molecular dynamics simulations of GaAs-crystal surface modifications during nanoindentation with AFM tip

The nanoindentation model of atomically flat surface of GaAs with the AFM tip was developed on the base of Molecular Dynamics. It was found that as a temperature rises above 100 K the nanoindention results in increase of number of atoms with higher number of neighbours, i.e. point defect appears in the topmost atomic layers of GaAs. The observed results can be explained with the kinetic concept of the mechanism of fracture of solid state where the generation of native point defects caused by the fluctuation of thermal energy and the external stress results in enhancement of the defect generation rate. (paper)