Dynamics of atoms around the interface of tip and substrate has close relationship to adhesive forces. This paper investigates the interactive behaviors by utilizing molecular dynamic (MD) simulation with the consideration of external applied electrostatic (ES) field between the atomic force microscopy (AFM) tip and substrate, which are both coated with gold. Morse potential was employed herein for modeling the energy between the atoms on the tip and substrate. The simulation model is composed of the gold-coated parts of the AFM tip and substrate, which are connected to the rest parts of the AFM tip and substrate, respectively, by the use of boundary conditions. The gold atoms were arranged in order according to face centric cubic (FCC) structure. The tip with the pyramidal shape was formed from 664 gold atoms while the substrate with cuboid shape was constructed from 2400 gold atoms. Simulation results show that both jump-to-contact interactions and the atom transfer increase as a result of enhancing the bias voltage between the tip and the substrate. The results agree well with experimental observation and also have the same trend as the experiment.

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