Abstract
We report on the direct fabrication of single-crystalline wurtzite-type hexagonal
GaN
nanotubes via a newly designed, controllable, and reproducible chemical thermal-evaporation process. The nanotubes are single crystalline, have one end closed, an average outer diameter of
∼
300
nm
, an inner diameter of
∼
100
nm
, and a wall thickness of
∼
100
nm
. The structure and morphology of the tubes are characterized using a scanning electron microscope and a transmission electron microscope. The cathodoluminescence of individual nanotubes is also investigated. The growth mechanism, formation kinetics, and crystallography of
GaN
nanotubes are finally discussed.