Growth of atomically smooth cubic AlN by molecular beam epitaxy

Abstract

In this work we present the growth of atomically flat c-AlN layers (surface roughness 0.3 nm RMS) by plasma assisted molecular beam epitaxy (PAMBE) on 3C-SiC. We develop a model for Al surface kinetics that correlates with RHEED intensity vs. time measurements. We show RHEED patterns and atomic force microscopy (AFM) scans emphasizing the quality of the layers. Ellipsometry yields the dielectric function of c-AlN around the adsorption edge. The direct gap is obtained with 5.93 eV at room temperature, while the indirect one is below 5.3 eV (onset of adsorption). © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.