SURFACE-ANALYSIS OF 6H-SIC

The composition of {0001} surfaces of 6H-SiC samples was studied by us ing low-energy electron diffraction, Auger electron (AES), and X-ray p hotoelectron spectroscopy (XPS/SXPS). The samples were cleaned in ultr ahigh vacuum by heating them either in the presence of a Si flux at di fferent temperatures or by annealing at 1170 K for 10 min. Depending o n the preparation method and temperature used four reconstructions wer e observed: (1x1), (3x3), (root 3x root 3)R30 degrees, and (6 root 3x6 root 3)R30 degrees. The compositions of the reconstructions and the c hemical bonding of the surface atoms were characterized using AES and XPS/SXPS. Models for the reconstructions are proposed.