Controlled Self-formation of GaN Nanotubes by Inductively Coupled Plasmas Etching

In this work, we fabricated GaN hollow nanorods by using inductively coupled plasma (ICP) etching. We found that tops of these nanotubes were hexagonal with the c-axis perpendicular to substrate surface. We also found that density of the GaN nanorods were not strongly dependent on etching parameters, which suggests that the formation of these GaN nanotubes was related to the dislocation density in the original GaN epitaxial layers. Furthermore, it was found that we could reduce the dimension and increase the density of the GaN nanotubes by decreasing the Ar concentrations during ICP etching