Controlled growth of nanostructured III-nitride films via a reactive magnetron sputtering method

Nanostructured films of AlN, GaN, and InN were grown via a reactive magnetron sputtering technique without templates or catalyst. The growth of nanorod arrays or two-dimensional compact films can be switched by fine tuning nitrogen content in sputtering gas. The nanorods grow along [0 0 1] direction with a diameter of ∼100–500 nm. AlN has a cone shape with an apical tip radius of ∼2 nm. A growth mechanism involving in the mobilities of metallic adatoms (such as Ga, Al, and In) and N adatoms on different crystallographic planes is presented for formation of nanorod arrays.