RHEED and AES study of Si (111).RAD.3*.RAD.3-R30.DEG. structure induced by adsorption of impurity gases.

Abstract

A √3×√3 RHEED pattern was first observed for a Si(111) surface annealed at about 900 K after exposure of hydrogen gas with a very small amount of impurity gases. A profile of C-KLL Auger electron spectrum is similar to that of SiC state. Annealing the surface at about 1100 K, SiC pattern was observed in the RHEED pattern. Rocking curves of RHEED intensities from the √3×√3 surface was similar to that from clean Si(111) 1×1 with diffuse √3×√3 surface at high temperature. Since the amount of carbon atoms were very small, it is considered that the √3×√3 structure is similar to that at high temperature and pinned by carbon atoms.