论文部分内容阅读
采用嵌入原子方法的原子间相互作用势,利用分子动力学方法计算了同质外延生长中不同层数的三维Cu(111)表面岛上表面原子扩散激活能,分析了三维表面岛的层数对表面原子交换扩散和跳跃扩散势垒的影响.研究结果表明,二维Enrilich_Schwoebel(ES)势垒小于三维ES势垒,且三维ES势垒不随表面岛层数的增加而显著变化.对于侧向表面为(100)的表面岛,表面原子沿〈01-1-〉方向上的扩散行为,随表面岛层数增加而逐渐变化;在表面岛层数达到3层时,扩散路径上的势垒变化趋于稳定,表面原子扩散以下坡扩散为主.对于侧面取向为(1-1-1)的表面岛,当表面岛层数大于3层后,开始呈现上坡扩散的可能.
By using the intermolecular interaction potential of the embedded atomic method, the atomic diffusion activation energy of three-dimensional Cu (111) surface islands in different layers in homoepitaxial growth was calculated by molecular dynamics method. The number of layer pairs The results show that the two-dimensional Enrilich_Schwoebel (ES) barrier is smaller than the three-dimensional ES barrier, and the three-dimensional ES barrier does not change significantly with the number of surface islands. For the lateral surface (100), the diffusion behavior of the surface atoms in the <01-1-> direction gradually changes with the increase of surface island number. When the number of surface island layers reaches 3, the barrier change in the diffusion path The surface atom diffusion is dominated by downhill diffusion.For the surface island whose orientation is (1-1-1), when the number of surface islands is more than 3, it is possible to start uphill diffusion.