The (3×3)R30° reconstruction on hexagonal 6H–SiC(0 0 0 1) surface with and without a Si flux

The (3×3)R30° reconstruction on hexagonal 6H–SiC(0 0 0 1) surface and its properties were studied by using reflection high-energy electron diffraction (RHEED) and RHEED multislice dynamical calculations. A Si coverage of 1/3 monolayer occupying the threefold-symmetric T4 or H3 sites develops upon a lower Si flux and/or at a higher annealing temperature and/or upon a longer time annealing. However, Si trimers centered on the T4 positions with 1 monolayer coverage may be another appropriate candidate for the (3×3)R30° reconstruction obtained under a very Si-rich condition and/or at a lower annealing temperature and/or upon a shorter time annealing.