论文标题
通过平均原子模型了解多晶膜中的内在压缩
Understanding the intrinsic compression in polycrystalline films through a mean-field atomistic model
论文作者
论文摘要
穆林斯的理论预测了在凹槽边缘的表面扩散期间的沉积物的堆积，其中晶界出现到多晶膜的表面。然而，该理论的介观性阻止了这种现象所涉及的原子尺度物理机制的鉴定。在这里，我们通过平均场速率方程模型来解释原子术语中的ADATOM的积累，并证明了其动力学性质及其对这些系统内在应力的影响。此外，该模型提供了内在应力的表面曲线，其典型平均值的表面曲线以及应力对不同生长阶段的温度和沉积通量的依赖。这些估计与报告的实验结果相吻合，从多晶膜表面上的机械应力的纳米级映射中获得的实验结果一致。
Mullins' theory predicts the buildup of adatoms during surface diffusion at the edges of grooves where grain boundaries emerge to the surface of a polycrystalline film. However, the mesoscopic nature of this theory prevents the identification of the atomic scale physical mechanisms involved in this phenomenon. Here, we interpret the buildup of adatoms in atomistic terms through a mean-field rate-equation model and demonstrate both its kinetic nature and its impact on the intrinsic stress in these systems. Furthermore, the model provides estimates of the surface profile of intrinsic stress, of its typical mean values, and of the dependence of stress on temperature and deposition flux for different growth stages. These estimates agree well with reported experimental results obtained from recent advances in nanoscale mapping of mechanical stresses on the surface of polycrystalline films.
