Improvement of the surface morphology of a-plane InN using low-temperature InN buffer layers

We report on the improvement of the surface morphology of a -plane InN films grown by RF molecular beam epitaxy. By using low-temperature (LT) InN buffer layers, we could successfully obtain InN films with a smooth surface. The full width at half maximum values of the x-ray diffraction (11-20) rocking curve along the [0001] InN direction were 2870 arcsec and 3410 arcsec for a -plane InN samples grown at 500°C with and without LT-InN buffer layers, respectively. Thus, we could improve also the crystalline quality of a -plane InN films by using LT-InN buffer layers. We observed strong polarization anisotropy in the photoluminescence spectra of a -plane InN, which is typical of nonpolar wurtzite III-nitride films. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)