Dynamically stable gallium-induced 3×3-SiC (0001) surface for two-dimensional GaN nucleation by molecular-beam epitaxy.

Two-dimensional (2D) GaN nucleation on a gallium (Ga) induced 3×3-SiC (0001) surface was achieved by molecular-beam epitaxy. The Ga adsorbate on SiC (0001) revealed well-ordered [square_root_of_3]×[square_root_of_3]-R30° and 3×3 surface reconstructions with respect to Ga adatom coverage. The 3×3 surface was found to be highly reactive toward 2D GaN nuclei. This enhances the surface mobility of impinging adatoms during GaN growth, which promotes a step-flow growth mode. On the [square_root_of_3]×[square_root_of_3]-R30° surface, polygonal Stranski–Krastanov islands formed during the initial stages, coalescing as thickness increased. The GaN growth kinetics was found to depend on the Ga atomistic process of the reconstructed SiC (0001) surfaces. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]