Abstract The epitaxial growth of GaN on AlN substrate is investigated by using the molecular dynamics simulation. The effects of substrate rotating speed, the effusion source inclined angle, the substrate temperature and the flux ratio of Ga and N atoms are simulated and studied. The variation of the surface morphology and atomic scale structure are discussed in detail. It is observed that the roughness decreases rapidly as the rotating speed increases from 0 to 2 revolutions per monolayer. The crystalline quality is improved as the rotating speed increases from 0 to 5 revolutions per monolayer. The surface roughness keeps a small change as the incident angle increases from 15° to 45° and then increases significantly with further increase of incident angle. However, the wurtzite composition of the structure components presents a positive correlation with the incident angle. The surface morphology is much better at the N: Ga flux ratio of 0.8 than at the ratio of 1.2 and the crystalline quality at the N: Ga flux ratio of 1 is better than that at the ratio of 1.2 and 0.8 in overall trend. However, the crystalline quality at the N: Ga flux ratio of 0.8 is improved significantly and surpasses the crystalline quality at the ratio of 1 under a relatively high temperature.

中文翻译：

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GaN分子束外延生长的分子动力学模拟研究

摘要 利用分子动力学模拟研究了氮化镓在氮化铝衬底上的外延生长。模拟研究了衬底转速、射流源倾斜角、衬底温度和Ga、N原子通量比的影响。详细讨论了表面形貌和原子尺度结构的变化。观察到随着旋转速度从每单层 0 转增加到 2 转，粗糙度迅速降低。随着旋转速度从每单层 0 转增加到 5 转，结晶质量得到改善。随着入射角从15°增加到45°，表面粗糙度保持很小的变化，然后随着入射角的进一步增加而显着增加。然而，结构成分的纤锌矿成分与入射角呈正相关。表面形貌在 N:Ga 通量比为 0.8 时比在 1.2 时好得多，在 N:Ga 通量比为 1 时的晶体质量总体趋势上比在 1.2 和 0.8 时好。然而，N：Ga通量比为0.8时的结晶质量显着提高，并且在相对较高的温度下超过了1的结晶质量。