  We investigate the effect of the formation of metal droplets on the growth
dynamics of InGaN by Plasma-Assisted Molecular Beam Epitaxy (PAMBE) at low
temperatures (T = 450{\deg}C). We find that the presence of droplets on the
growth surface strongly affects the adatom incorporation dynamics, making the
growth rate a decreasing function of the overall metal flux impinging on the
surface as soon as the metal dose exceeds the critical amount required for the
nucleation of droplets. We explain this phenomenon via a model that takes into
account droplet effects on the incorporation of metal adatoms into the crystal.
A relevant role is played by the vapor-liquid-solid growth mode that takes
place under the droplets due to nitrogen molecules directly impinging on the
droplets.
