The quasistatic approximation is a useful but questionable simplification for analyzing step instabilities during the growth/evaporation of vicinal surfaces. Using this approximation, we characterized in Part I of this work the effect on stability of different mechanisms and their interplay: elastic step-step interactions, the Schwoebel barrier, and the chemical coupling of the diffusion fields on adjacent terraces. In this second part, we present a stability analysis of the general problem without recourse to the quasistatic approximation. This analysis reveals the existence of a supplementary mechanism, which we label the “dynamics effect” as it follows from accounting for all the convective and transient terms in the governing equations. This effect can be stabilizing or destabilizing depending on the ratio of step attachment/detachment kinetics to terrace diffusion kinetics. Further, we find that this dynamics effect remains significant in the slow deposition/evaporation regime, thereby invalidating the classical postulate underlying the quasistatic approximation. Finally, revisiting experiments of crystal growth on Si(111)-7 $\times$ 7 and GaAs(001), our analysis provides an alternative explanation of the observed step bunching, one that does not require the mechanisms previously invoked in the literature.

准静态近似是一种有用但有问题的简化方法，用于分析相邻表面生长/蒸发过程中的步骤不稳定性。使用这种近似，我们在本工作的第 I 部分描述了不同机制及其相互作用对稳定性的影响：弹性阶梯相互作用、施沃贝尔势垒以及相邻阶地扩散场的化学耦合。在第二部分中，我们对一般问题进行了稳定性分析，而无需求助于准静态近似。该分析揭示了一种补充机制的存在，我们将其称为“动力学效应”，因为它解释了控制方程中的所有对流和瞬态项。根据台阶附着/分离动力学与平台扩散动力学的比率，这种效应可能是稳定的或不稳定的。此外，我们发现这种动力学效应在缓慢沉积/蒸发状态下仍然显着，从而使准静态近似下的经典假设无效。最后，重温在 Si(111)-7 上的晶体生长实验 $\times$ 7 和 GaAs(001)，我们的分析提供了对观察到的阶跃聚束的另一种解释，这种解释不需要先前在文献中调用的机制。