  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)-7x7 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.
