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用Monte Carlo方法以Cu为例对薄膜生长过程进行了计算机模拟。不仅对原子的吸附、迁移及脱附三种过程采用了更为合理的模型,还考虑了这些过程发生时对近邻原子的连带效应。在合理选择原子间互作用势计算方法的基础上,改进了原子迁移激活能的计算方法。计算了表征薄膜生长表面形貌的表面粗糙度和表征薄膜内部晶格完整性的相对密度。结果表明,在一定的原子入射率下,表面粗糙度和相对密度的变化存在一个生长最佳温度。随着衬底温度的升高,表面粗糙度减小,膜的相对密度增大。当达到生长最佳温度时,粗糙度最小,而相对密度趋于饱和。粗糙度随衬底温度的进一步升高开始增大。生长最佳温度随原子入射率的增大而增大,不同温度下原子入射率对粗糙度的影响不同,在较低温度时粗糙度随入射率的增加而增加,在较高温度时粗糙度随入射率增大而减小。同时发现,随入射率的增大或薄膜厚度的增加,相对密度逐渐减小。
The Monte Carlo method with Cu as an example of the film growth process of computer simulation. Not only the adsorption, migration and desorption of atoms using three more reasonable process model, but also consider these processes occur when the incidental effects of neighboring atoms. On the basis of reasonable calculation of the interaction potential between atoms, the calculation method of atomic migration activation energy is improved. The surface roughness characterizing the morphology of the growth surface of the film and the relative density characterizing the lattice integrity of the film were calculated. The results show that at a certain atomic incident rate, the change of surface roughness and relative density has the best growth temperature. As the substrate temperature increases, the surface roughness decreases and the relative density of the film increases. When the optimum growth temperature is reached, the roughness is smallest and the relative density tends to be saturated. Roughness increases with increasing substrate temperature. The optimum growth temperature increases with the atomic incident rate. At different temperatures, the influence of atomic incident rate on roughness is different. At lower temperature, the roughness increases with the increase of incident rate. At the higher temperature, the roughness Decreases with increasing incident rate. It is also found that the relative density decreases with the increase of the incident rate or the increase of the film thickness.