MD simulations of Ag film growth using the Lennard-Jones potential

The nucleation and growth of Ag films on a Cu(100) substrate were studied by molecular dynamics simulation using Lennard-Jones (L-J) interactions. Different mechanisms were found for island formation on low- and high-temperature substrates. Improved agreement between the simulation and experimental LEED patterns was obtained when the L-J interaction was modified to take into the account the location of the atoms on the surface or in the bulk. The simulation predicted a unit mesh and low surface roughness, as was observed experimentally. The L-J interaction gives three-dimensional growth, but can be made to reproduce the observed layer by layer growth if the force constant for surface atoms is further modified.