Atomistic simulation study of the diffusion and growth mechanisms of Ti thin films on Si(100) surfaces for betavoltaic cell

摘要: The nucleation and growth behavior of Ti thin films on Si(100) surfaces at 500 K were investigated via molecular dynamics and Monte Carlo methods. The focus of this study was on the nucleation characteristics,growth mode, crystal structure and surface structure of the Ti thin films for use in betavoltaic cell. The results demonstrate that at the initial stage of deposition, mixing of Ti films with Si substrates occurs at the interface. The surface roughness of Ti films is influenced by the deposition atomic rate, which is associated with the crystal structure transition in the films, and the stable HCP grains in the films are frequently accompanied by an FCC laminated dislocation structure. As the deposition rate increased, the growth mechanism of the Ti films transitioned from a random orientation to a selective orientation. Furthermore, we recalculated the adsorption energies of Ti at different adsorption sites on the Si(100)p(2×2) surface. This was done to identify the optimal diffusion path of Ti atoms on the Si(100) surface, which was then found via the transition state search method.