镀膜玻璃衬底表面结构的分子动力学模拟

为考察硅酸盐玻璃衬底的表面结构以及温度对玻璃衬底表面结构的影响，模拟研究了500～1 000 K温度范围内及Al质量分数为0.5%～1.5%的玻璃衬底结构.采用Born-Mayer势函数,使用分子动力学方法，模拟了玻璃体相结构向表面结构转化的结构驰豫过程.结果表明，结构驰豫使系统能量下降，原子向表面一侧扩散.在500～1 000 K温度范围内，玻璃成份中Na原子的驰豫最为明显，Ca原子次之，Si、O原子最小，玻璃衬底表面的Na原子的质量分数高于体相.随着玻璃成份中Al质量分数的减小，玻璃衬底表面层的能量增加，活性增强，有利于沉积原子的吸附.

Molecular dynamic simulation on substrate surface of coating glass

To investigate the surface structure and the temperature dependence on the surface structure, the surface of silicate glass substrate was simulated under 500-1000K and 0.5%-1.5% mass percent of Al. The Born-Mayer potential function was employed, and the molecular dynamics method was used to model the structure relaxation process of bulk structure to surface structure. The results show that the structural relaxation of the surface reduces the system energy of the substrate. The relaxation of Na atoms is the most intensive, then the Ca atoms, while the Si and O atoms are the least at 500-1000K. The mass percent of Na in glass substrate surface area is higher than that in the bulk area. The surface energy increases with decreasing Al mass percent, low Al mass percent enhances the surface activity, and is helpful for the absorption of deposition atoms.