标题： 二维ASEP模型用于研究CVD生长中的密度分布 显示英文标题

标题： Two-dimensional ASEP model to study density profiles in CVD growth

摘要： 二维(2D)过渡金属二硫属化物通过化学气相沉积的生长已成为一个广泛研究的领域，主要是由于潜在器件应用的可扩展性要求。 这种生长的主要挑战之一是生长薄膜的大规模厚度变化。 为了计算研究不同生长参数的作用，我们使用一个具有开放边界的二维不对称简单排斥过程(ASEP)模型，作为粗粒度晶格上沉积动力学的近似。 在生长薄膜中，晶格位点的粒子浓度(生长剖面)被研究为参数如粒子从晶格的注入和排出速率、观察时间以及由载气施加的右偏置(向右和向左跳跃概率的差异)的函数。 此外，假设在给定的粗粒度位点的沉积速率取决于该位点的占据情况。 已经探讨了最大沉积速率的影响，即基底上完全未占据位点的沉积速率。 当演化时间或右偏置增加时，生长剖面会水平延伸。 增加的沉积速率会导致阶梯状的剖面，高密度区域靠近左侧边缘。 在三维情况下，随着前驱体相对于基底表面的高度增加，生长剖面变得更加均匀。 这些结果与实验观察定性一致。 显示英文摘要

摘要： The growth of two-dimensional (2D) transition metal dichalcogenides using chemical vapor deposition has been an area of intense study, primarily due to the scalability requirements for potential device applications. One of the major challenges of such growths is the large-scale thickness variation of the grown film. To investigate the role of different growth parameters computationally, we use a 2D asymmetric simple-exclusion process (ASEP) model with open boundaries as an approximation to the dynamics of deposition on the coarse-grained lattice. The variations in concentration of particles (growth profiles) at the lattice sites in the grown film are studied as functions of parameters like injection and ejection rate of particles from the lattice, time of observation, and the right bias (difference between the hopping probabilities towards right and towards left) imposed by the carrier gas. In addition, the deposition rates at a given coarse-grained site is assumed to depend on the occupancy of that site. The effect of the maximum deposition rate, i.e., the deposition rate at a completely unoccupied site on the substrate, has been explored. The growth profiles stretch horizontally when either the evolution time or the right bias is increased. An increased deposition rate leads to a step-like profile, with the higher density region close to the left edge. In 3D, the growth profiles become more uniform with the increase in the height of the precursor with respect to the substrate surface. These results qualitatively agree with the experimental observations.