Molecular Dynamics Simulations Of Temperature Effects On Pt/Au Heteroepitaxial Growth

Heteroepitaxial growth is an important research direction in thin film field. We should study the atomic level to recognize the physical nature of the heterogeneitaxial thin film growth,, whether it isthe improving improvement of the preparation process, and or to the enhancement of the quality of films have plays a very important role in guiding. In this paper, we use computer simulation method to simulate Au/Pt (001) and Pt/Au (001) heteroepitaxial growth, using by the EAM interaction potential between atoms and, respectively, for Au/Pt (001) and Pt/Au (001) heteroepitaxial growth has been simulated,analyzed the effect of the film surface roughness with the different substrate temperature on the film surface roughness, the film growth mode, film and substrate interdiffusion phenomena at the interface and the changing relationship of relative density of atomic layer film of the changes in the relationship and so on. We analyze the difference between Au/Pt thin film and Pt/Au thin film in the external conditions.In this paper, the main conclusions are:1,Pt/Au epitaxial thin film growth mode with different deposition temperature: Pt/Au system in the initial stage of growth shows two-dimensional layer growth mode between 300K and 700K.But with the extension of time, Pt films will be showing a three-dimensional island-like growth pattern at 300K. At 500K and 700K, the film growth mode gradually transforms to the layer growth. At 700K, Pt films exhibite a clear layer growth characteristics.2,The deposition temperature affects Pt/Au epitaxial film structure:Pt/Au film surface morphology gradually transforms to glossy from roughness and the internal atomic arrangement becomes increasingly dense.3,The deposition temperature influences Pt/Au epitaxial film interface interdiffusion:Pt/Au thin film interdiffusion phenomena at the interface with the deposition temperature. At 300K and 500K, the interface interdiffusion has only 2-3 atomic layers and the diffusion of atoms is also small, while and 700K, the interface interdiffusion is up to 7-9 atomic layers and there are a lot of inter-atomic diffusion. 4,The regular is similar when we analyze the influence of the epitaxial growth of Au/Pt system with the different temperature. However, Au/Pt system shows lower surface roughness than the Pt/Au system and no interface interdiffusion phenomena in the same conditions.