Structural analysis of 6H-SiC(0001) root 3 x root 3 reconstructed surface

Using coaxial impact-collision ion scattering spectroscopy (CAICISS), the s tructure of the 6H-SiC(0001)root3 x root3 reconstructed surface was investi gated. As a result of composition analysis, the topmost layer of this surfa ce was found to be covered with Si adatoms. Moreover, from the incidence an gle dependence of the scattering intensity due to C atoms, it was found tha t the root3 x root3 periodicity was formed by a one-third monolayer of Si a datoms occupying T-4 sites, and the height of the Si adatoms from the first substrate layer was determined to be 1.5 +/- 0.2 Angstrom.