Grain boundary and interface migration were observed, during phase transformation in nm-grained polycrystals, by means of dynamic high-resolution transmission electron microscopy. The migration of a [2¯1•0] tilt grain boundary was found to proceed via the movement of ledges which corresponded to the structural units of the boundary. The phase transformed from a wurtzite to a zincblende structure, following migration of the interface. Interface migration also proceeded via the movement of ledges. The lattice misfit at the grain boundary and interface was lower following grain-boundary migration and phase transformation.

Atomic Processes of Grain-Boundary Migration and Phase Transformation in Zinc Oxide Nanocrystallites. T.Kizuka: Philosophical Magazine Letters, 1999, 79[7], 417-22