GaN nanostructures grown on Si(111) by PA-MBE via droplet epitaxy: SEM and HRTEM study

In this report, we demonstrate that the use of GaN seeding layer prepared by droplet epitaxy technique using plasma assisted molecular beam epitaxy (PA-MBE) can lead to the epitaxial stabilization of GaN nanostructures with different lattice orientations. From the high-resolution transmission electron microscopy (HRTEM) studies, it is shown that {111} faceted zinc-blende (ZB) GaN islands act as the fast nucleation sites for the growth of GaN nanowires (NWs) with hexagonal wurtzite (WZ) structure. Further GaN nanostructure morphology depends on lattice orientation of the seeding island. It will be shown that further intergrowth and coalescence of GaN NWs lead to changes in the mutual orientation. (paper)