Early stages of silicon nitride film growth studied by molecular dynamics simulations

The molecular dynamics method is used to simulate silicon nitride film growth through atomic deposition on an amorphous silicon surface, which is modeled by the stochastic classical trajectory-ghost theory. For the first time, realistic semi-empirical interatomic potential including both two-body and three-body interactions is employed to calculate the forces among deposited atoms. By the simulation we studied growth kinetics and the effects of substrate temperature and kinetic energy of vaporized atoms on the film growth. It is found that the film growth follows power law mechanism but with two different growth exponents in different growth stages, and changes of the substrate temperature and atomic kinetic energy lead to various film morphologies. This provides a possibility to precisely control the film properties, especially cluster size and compactness, by choosing suitable deposition parameters.