Surface features on flux-grown refractory oxide crystals

The mechanism by which crystals grow from the flux is normally by layers spreading from screw-dislocation sources, forming growth hillocks. Alternative mechanisms are not uncommon and twin domains have been found to provide the dominant growth centres in some rare-earth aluminate crystals, in which the angle between twins is only of the order of 1°. Other factors such as edge nucleation and the mutual influence of adjacent crystal faces are also discussed. © 1973.