The a-plane AlN films were grown onto ZnO substrates using room-temperature epitaxial GaN buffer layers by pulsed laser deposition. The basal plane stacking fault density of these AlN(11•0) films, as estimated from X-ray rocking curve measurements, was as low as 1.1 x 105/cm, which was attributed to the use of ZnO substrates with a small lattice mismatch. Cathode luminescence spectra measured at 300K exhibited a clear near band-edge peak of AlN at around 5.9eV. The use of a pulsed laser deposition low-temperature growth technique and ZnO substrates would be quite attractive for the fabrication of ultraviolet light-emitting devices.

Structural and Optical Properties of Nonpolar AlN(1120) Films Grown on ZnO(1120) Substrates with a Room-Temperature GaN Buffer Layer. K.Ueno, A.Kobayashi, J.Ohta, H.Fujioka: Japanese Journal of Applied Physics, 2010, 49[6], 060213