Abstract
In order to clarify friction phenomena generated in the surface observation processes by atomic force microscope (AFM), several molecular dynamics simulations have been performed. In the simulations, a 3-dimensional simulation model is proposed where the specimen and the probe are assumed to consist of mono-crystalline copper and rigid diamond, respectively, and the effect of cantilever stiffness of AFM is also taken into consideration by connecting the springs with the probe in 3-axis directions. The friction process without wear on a well-defined copper {100} surface by a diamond probe is simulated. From the simulation results, atomic-scale stick-slip phenomenon just like observed in the AFM surface observation is realized. Generation of the 2-dimensional friction process even in one-dimensional sliding simulation is confirmed. Influences of the point defect in the specimen surface and the probe tip shape on observed surface image are also evaluated. These results indicate that the molecular dynamics simulation has an advantage in estimating the various phenomena in AFM surface observation.
